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find Keyword "形态学" 32 results
  • MORPHOMETRIC STUDY OF COLLAGEN FIBERS DURING HEALING FOLLOWING PARTIAL AND COMPLETE SECTION OF EXTENSOR TENDONS IN RATS

    In order to study the influence of severity of tendon injury on the morphology of collagen fibers during healing process of extensor tendons, 40 female Wistal rats were used for investigation. The rats were divided into 2 groups. Transection of the tendon of extensor digitorum longus was performed in one group, while partial section of the same tendon was performed in the other group. Morphometric analysis was undertaken on the 15th, 30th, 60th and 90th day after operation. The result was that there was no significant difference between the two groups both in distribution and diameter of collagen fibers on the 15th and 30th days (P gt; 0.05). However, there was significent difference between those on the 60th and 90th days (P lt; 0.05). It was concluded that the severity of the tendon injury could influence the morphology of collagen fibers during the late stage of tendon healing.

    Release date:2016-09-01 11:08 Export PDF Favorites Scan
  • MORPHOLOGICAL OBSERVATION ON REPAIRING ARTICULAR CARTILAGE DEFECTS WITH COLLAGENCOMPLEX GRADIENT TCP

    Objective To repair the defects in articular cartilage with collagen complex gradient TCP in vivo andto study the regenerated cartilage histomorphologically. Methods The models of defects in articular cartilage were madeartificially in both condylus lateral is femoris of mature rabbits, male or female, with the weight of 2.0-2.5 kg. The right defects were implanted with the material of Col/TCP as the experimental group and the left defects were untreated as the control group. The rabbits were killed at 4, 6, 8, 12 and 24 weeks after operation, respectively, with 6 ones at each time, and the macroscopic, histological, ultrastructural examinations and semi-quantity cartilage scoring employing Wakitanifa repaired cartilage value system were performed. Results Four weeks after operation, the defects in the experimental group were partly filled with hyal ine cartilage. Twelve weeks after operation, the defects in the experimental group were completely filled with mature hyal ine cartilage. Twenty-four weeks after operation, regenerated cartilage had no ataplasia. However, fibrous tissues were seen in the control group all the time. At 4, 6, 8, 12 and 24 weeks ostoperatively, the Wakitanifa cartilage scores were 7.60 ± 0.98, 5.69 ± 0.58, 4.46 ± 0.85, 4.35 ± 0.12 and 4.41 ± 0.58, respectively, in the experimental group and 10.25 ± 1.05, 9.04 ± 0.96, 8.96 ± 0.88, 8.88 ± 0.68 and 8.66 ± 0.54, respectively, in the control group. At 4, 6, 8, 12 and 24 weeks postoperatively, the collagen II contents were 0.28% ± 0.01%, 0.59% ± 0.03%, 0.68% ± 0.02%, 0.89% ± 0.02% and 0.90% ± 0.01%, respectively, in the experimental group, while 0.08% ± 0.02%, 0.09% ± 0.04%, 0.11% ± 0.03%, 0.25% ± 0.03% and 0.29% ± 0.01%, respectively, in the control group. Differences between the control group and the experimental group were significant (P lt; 0.05). By then, typical chondrocyte was observed by transmission electron microscope in the experimental group and much fiber with less fibrocyte was observed in the control group. Conclusion Three-dimensional scaffold collagen complex gradient TCP may induce cartilage regeneration to repair the defects of articular cartilage in vivo.

    Release date:2016-09-01 09:16 Export PDF Favorites Scan
  • Pretreatment of tear film video in corneal topography

    In the evaluation of tear film stability based on corneal topography, a pretreatment algorithm for tear film video was proposed for eye movement, eyelash reflection and background interference. First, Sobel operator was used to detect the blur image. Next, the target image with highlighted ring pattern was obtained by the morphological open operation performed on the grayscale image. Then the ring pattern frequency of the target image was extracted through the Hough circle detection and fast Fourier transform, and a band-pass filter was applied to the target image according to the ring pattern frequency. Finally, binarization and morphological closed operation were used for the localization of the ring pattern. Ten tear film videos were randomly selected from the database and processed frame by frame through the above algorithm. The experimental results showed that the proposed algorithm was effective in removing the invalid images in the video sequence and positioning the ring pattern, which laid a foundation for the subsequent evaluation of tear film stability.

    Release date:2020-02-18 09:21 Export PDF Favorites Scan
  • Effects of SMILE with different residual stromal thicknesses on corneal biomechanical properties of rabbits in vivo

    Femtosecond laser small incision lenticule extraction (SMILE) with different residual stromal thicknesses (RST) is set to investigate its effect on corneal biomechanical properties of rabbits in vivo. In this study, 24 healthy adult Japanese rabbits were randomly divided into group A and B. The RST of group A was set 30% of the corneal central thickness (CCT), and the RST of group B was 50% of the CCT. The thickness of the corneal cap in both groups was set one third of CCT. Corneal visualization Scheimpflug technology (Corvis ST) and Pentacam three-dimensional anterior segment analyzer were used to determine corneal biomechanical and morphological parameters before surgery, and 1 week, 1 month and 3 months after surgery. Pearson correlation analysis was used to analyze factors affecting corneal biomechanical parameters after SMILE. The results showed that the corneal stiffness of group A was significantly higher than that of group B at 1 week and 1 month after surgery, and most biomechanical parameters returned to preoperative levels at 3 months postoperatively. The results of correlation analysis showed that postoperative CCT and RST were the main factors affecting corneal biomechanical parameters after SMILE. There was no significant difference in corneal posterior surface height (PE) between 3 months after surgery and before surgery in both two groups. It indicates that although the ability to resist deformation of cornea decreases in SMILE with thicker corneal cap and less RST, there is no tendency to keratoconus, which may be related to the preservation of more anterior stromal layer.

    Release date:2022-10-25 01:09 Export PDF Favorites Scan
  • Prediction of Hyperfibrinogenemia Combined with Multi-Slice Spiral Computed Tomography Image for Identification of Metastatic Lymph Node in Colorectal Cancer

    Objective To establish the optimal morphological criteria combined with fibrinogen level for evaluation of lymph node metastasis in colorectal cancer. Methods A consecutive series of 690 patients who underwent curative surgery for colorectal cancer, were examined by abdominopelvic enhanced multi-slice spiral computed tomography (MSCT) scan. If regional lymph nodes appeared, the maximal long-axis diameter (MLAD), maximal short-axis diameter (MSAD), and axial ratio (MSAD/MLAD) were recorded. At each lymph node size cut-off value, the following were calculated: accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Moreover, preoperative plasma level of fibrinogen was retrospectively examined to identify metastatic or inflammatory lymph node combined with MSCT image. Both modalities, MSCT plus fibrinogen and MSCT alone, were compared based on the pathologic findings. Results The study population consisted of 100 patients with regional lymph nodes show. No significant difference was found between metastatic and inflammatory lymph nodes in imaging characteristics (Pgt;0.05). The best cut-off value of MSAD was 6 mm for lymph node metastasis with the sensitivity of 46.8%, specificity of 68.4%, accuracy of 55.0%, PPV of 70.7% and NPV of 44.1%. The best cut-off value of MLAD was 8 mm with the sensitivity of 43.5%, specificity of 63.2%, accuracy of 51.0%, PPV of 65.9% and NPV of 40.7%. Using hyperfibrinogenemia (FIB ≥3.5 g/L) to identify small metastatic lymph node, of which MSAD lt;6 mm or MLAD lt;8 mm, showed statistical diagnostic value (Kappa=0.256, P=0.047). Compared with MSAD (6 mm) alone, MSAD (6 mm) combined with hyperfibrinogenemia had a higher sensitivity (79.0% vs. 46.8%, Plt;0.001), but a similar accuracy (66.0% vs. 55.0%, Pgt;0.05) and a lower specificity (44.7% vs. 68.4%, P=0.037). MLAD (8 mm) combined with hyperfibrinogenemia led to a greater diagnostic value in sensitivity (80.6% vs. 43.5%, Plt;0.001) and accuracy (66.0% vs. 51.0%, P=0.031) than MLAD (8 mm) alone, with a no-significantly decreasing specificity (42.1% vs. 63.2%, Pgt;0.05). Conclusions This present study recommend MSAD ≥6 mm or MLAD ≥8 mm as the optimal criteria for preoperative N staging in colorectal cancer. Moreover, the sensitivity and even accuracy could be improved by combining hyperfibrinogenemia for lymph node metastasis identification.

    Release date:2016-09-08 11:05 Export PDF Favorites Scan
  • Morphological analysis of coronal femoral intertrochanteric fracture and its effect on reduction and internal fixation

    ObjectiveTo investigate the morphology of coronal femoral intertrochanteric fracture and its effect on reduction and internal fixation.MethodsThe clinical and imaging data of 46 patients with femoral intertrochanteric fracture who met the selection criteria between August 2017 and October 2018 were reviewed. There were 15 males and 31 females; the age ranged from 62 to 91 years, with an average of 72.8 years. The causes of injury included walking falls in 35 cases, falling out of bed in 4 cases, and traffic accidents in 7 cases. The AO/Orthopaedic Trauma Association classification was type 31-A1 in 11 cases and type 31-A2 in 35 cases. All patients underwent closed reduction and internal fixation with intramedullary nails. During the operation, fracture reduction and fixation were performed according to the preoperative evaluation results. According to the patients’ preoperative X-ray film and CT three-dimensional reconstruction images, the direction of the coronal fracture line of the femoral intertrochanter and the morphological characteristics of the fracture block were observed; and the coronal fracture discrimination analysis was carried out for the fractures of different AO/OTA types. The percentages of coronal femoral intertrochanteric fractures diagnosed by preoperative X-ray film and CT three-dimensional reconstruction were calculated and statistically analyzed. The fracture reduction, the position of internal fixation [measurement of tip-apex distance (TAD)]. and the reliability of internal fixation were observed after operation.ResultsX-ray film was not easy to identify coronary fracture, and the coronal fracture line and the shape of the fracture piece weree clearly visible in CT three-dimensional reconstruction images. The morphological characteristics of the coronary fracture block: in AO/OTA 31-A1 type, the fracture line extended obliquely backward from the anterior tip of the large rotor, above the small rotor with or without small rotor fracture; in AO/OTA 31-A2 type, fracture line extended obliquely backward from the anterior tip of the large rotor to below the small rotor. Thirteen cases (28.3%) of coronal fractures were found on preoperative X-ray films, and 35 cases (76.1%) were found by CT three-dimensional reconstruction, showing significant difference (χ2=21.083, P=0.000). In AO/OTA 31-A1 type patients, the proportion of coronal fractures found by X-ray film and CT three-dimensional reconstruction was 18.2% (2/11) and 54.5% (6/11), respectively, and that in AO/OTA 31-A2 type patients was 31.4% (11/35) and 82.9% (29/35), respectively, showing significant differences (χ2=3.143, P=0.000; χ2=20.902, P=0.000). Among the 35 patients with coronal fractures, 6 cases (17.1%) of AO/OTA 31-A1 type, 29 cases (82.9%) of AO/OTA 31-A2 type. The operation time of the patient was 80-112 minutes, with an average of 95 minutes; the intraoperative blood loss was 180-450 mL, with an average of 360 mL. There was no complication such as infection, falling pneumonia, and deep vein thrombosis of the lower extremities. At 3 days after operation, the internal fixators were all in the proper position. The TAD was 0.9-1.8 cm, with an average of 1.4 cm. All patients were followed up 14-18 months, with an average of 16 months. All the fractures healed osseously, and there was no complication such as nonunion and loosening of internal fixation.ConclusionCT three-dimensional reconstruction can better identify coronal femoral intertrochanteric fractures than X-ray films, and accurately recognize and analyze the incidence and morphological characteristics of coronal fractures, which can help formulate more effective surgical strategies to promote patient recovery.

    Release date:2021-09-28 03:00 Export PDF Favorites Scan
  • Effectiveness of Different Embryo Screening Methods before Transplantation: A Systematic Review

    ObjectiveTo systematically review the effectiveness of traditional morphological embryo screening method and other screening methods. MethodsWe electronically searched PubMed, EMbase, Web of Knowledge, CBM, WanFang Data and CNKI, for studies about the effectiveness of traditional morphological embryo screening method and other screening methods from inception to July 1st, 2013. Two reviewers independently screened studies according to the inclusion and exclusion criteria, extracted data and evaluated the methodological quality of the included studies. Then meta-analysis was performed using the software RevMan 5.1. ResultsA total of 4 studies involving 951 patients were included. The results of meta-analysis showed that, for the traditional morphological embryo screening method, when compared with the NIR method and CCS method, there were no significant differences in clinical pregnancy rate (OR=0.94, 95%CI 0.57 to 1.53, P=0.80) and live birth rate (OR=0.90, 95%CI 0.60 to 1.37, P=0.63). However, significant difference was found for the embryos fragment rate (OR=0.40, 95%CI 0.27 to 0.59, P < 0.000 01). ConclusionThe current evidence shows that, compared with other methods, the traditional morphological embryo screening method could significantly reduce the embryos fragments rate. The results are needed to be further validate by more high-quality and large-scale studies.

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  • Detection of inferior myocardial infarction based on morphological characteristics

    Early accurate detection of inferior myocardial infarction is an important way to reduce the mortality from inferior myocardial infarction. Regrading the existing problems in the detection of inferior myocardial infarction, complex model structures and redundant features, this paper proposed a novel inferior myocardial infarction detection algorithm. Firstly, based on the clinic pathological information, the peak and area features of QRS and ST-T wavebands as well as the slope feature of ST waveband were extracted from electrocardiogram (ECG) signals leads Ⅱ, Ⅲ and aVF. In addition, according to individual features and the dispersion between them, we applied genetic algorithm to make judgement and then input the feature with larger degree into support vector machine (SVM) to realize the accurate detection of inferior myocardial infarction. The proposed method in this paper was verified by Physikalisch-Technische Bundesanstalt (PTB) diagnostic electrocardio signal database and the accuracy rate was up to 98.33%. Conforming to the clinical diagnosis and the characteristics of specific changes in inferior myocardial infarction ECG signal, the proposed method can effectively make precise detection of inferior myocardial infarction by morphological features, and therefore is suitable to be applied in portable devices development for clinical promotion.

    Release date:2021-04-21 04:23 Export PDF Favorites Scan
  • Anatomical calcaneal external fixator self-designed according to the morphology of heel

    ObjectiveThe anatomical calcaneal external fixator was designed by measuring and calculating the morphological data of the heel.MethodsA total of 100 normal people were randomly selected to obtain 200 hind foot data, including 45 males and 55 females, with an average age of 43.9 years (range, 19-67 years). According to the principles of human engineering and local anatomy, the morphological data of the heel in the weight-bearing standing position and supine position were measured with the direct measurement mode. The heel length, heel width, heel height, medial ankle height, lateral ankle height, and calcaneal pitch angle (CPA) were measured by vernier calipers and ulnar markers in weight-bearing standing position, and the gender groups and left and right foot groups were compared; the shape of the hind foot in the supine position was measured by three-dimensional (3D) dot matrix inverse model method. According to the stereoscopic data of the comprehensive anatomical morphology of the heel, the anatomical calcaneal external fixator was designed with AutoCAD 2019 and other 3D industrial design softwares.ResultsThe measurements of shoe size, heel length, heel width, heel height, medial ankle height, lateral ankle height, and CPA in male were significantly higher than those in female (P<0.05). There was no significant difference between the left and right feet in the other indexes except that the height of the medial malleolus of the left foot was significantly lower than that of the right foot (t=−2.827, P=0.005). The measurement of 3D dot matrix inverse model in supine position showed that the heel part was non-circular arc edge, and many groups of arc edges fluctuate in a limited range. Based on the above data, an anatomical calcaneal external fixator was designed, which could fit the anatomic radian in theory, so as to be flexible in configuration. On this basis, the ordinary configuration, compression configuration, and orthodontic configuration were designed to meet the treatment needs of calcaneal fractures in different degrees. The ordinary configuration was suitable for patients with Sanders Ⅰ, ⅡA, and ⅡB calcaneal fractures with no or slight displacement of intra-articular fractures; the ordinary configuration was mainly used for simple fixing. The compression configuration was suitable for patients with Sanders ⅡC, ⅢA, and ⅢB, tongue fractures, and avulsion fractures with severe displacement of intra-articular fractures; the compression configuration used obliquely drawn console wires to fix the displaced bones. The orthodontic configuration was suitable for patients with Sanders ⅢC and Ⅳ calcaneal fractures with severe displacement of intra-articular fractures or severe calcaneal bone defects; the orthodontic configuration was a multi-module design, which took into account the stable fixation of the fracture and the arbitrary adjustment of the joint fixation angle.ConclusionThe hind foot is special for morphology, so the external fixator designed based on the vernier caliper measurement method and 3D dot matrix measuring plate measurement method is an anatomical type and its configuration can theoretically meet stable and flexible clinical needs.

    Release date:2020-04-29 03:03 Export PDF Favorites Scan
  • HISTOMORPHOLOGICAL AND BIOMECHANICAL CHARACTERISTICS OF DECELLULARIZED BOVINE TENDONS

    Objective To investigate the effect of repeated freezing and thawing combining nuclease treatment on the decellularization of bovine tendons, and the morphology, structure, biochemical compositions, and mechanical properties of the decellularized tendons. Methods A total of 48 fresh 1-day-old bovine Achilles tendons were randomly divided into 3 groups (n=16): fresh normal tendons (group A), repeated freezing and thawing for 5 times (liquid nitrogen refrigeration/37℃ thawing, group B), and repeated freezing and thawing combining nuclease processing for 24 hours (group C). In each group, 2 tendons were used for scanning electron microscope (SEM), 3 tendons for histological and immunohistochemical observations, 3 tendons for DNA content detection, and 8 tendons for biomechanical testing. Results SEM observation indicated the intact, aligned, and densely packed collagen fibers with no disruption in groups A and B, and the slightly loose collagen fibers with little disruption in group C. The alcian blue staining, sirius red staining, and immunohistochemical staining showed that the most of glycosaminoglycan, collagen type I, collagen type III, and fibronectin in group C were retained after decellularization treatment. HE and DAPI staining showed that the cell nuclei between the collagen fibers were clearly visible in groups A and B; however, the cell nuclei between collagen fibers almost were invisible with a few residual nuclei on the endotendineum in group C. DNA quantitative detection confirmed that DNA content in group C [(0.05 ± 0.02) μg/mg] was significantly lower than those in group A [(0.24 ± 0.12) μg/mg] and group B [(0.16 ± 0.07) μg/mg] (P lt; 0.05). Biomechanical testing showed that the values of tensile strength, failure strain, stiffness, and elastic modulus were different among 3 groups, but no significant difference was found (P gt; 0.05). Conclusion Repeated freezing and thawing combining nuclease processing can effectively remove the component of cells, and simultaneously retain the original collagen fibrous structure, morphology, most of the extracellular matrix compositions, and mechanical properties of the bovine tendons.

    Release date:2016-08-31 04:07 Export PDF Favorites Scan
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