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find Keyword "structure" 160 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
  • AESTRACTS THE STUDY OF COMBINED DXM AND HAPARIN ON ULTRAMICROSTRUCTURE OF MDSCLE AND MICROCIRCULATION DURING DELATED REPLANTATION OF LIMB

    rough the ultramicroscopic observation on muscle and microcirculation, Group A,where a largeamount of DXM combined with heporin was given svstematically and locally into the femoral artery of the severed limb before replantation, and in Group B only heporin was given, and Group C and D ascontrol.The results showed that if the hormone and heparin were administred in large dosage, it wasadvantageous to reduce the tissues from reperfusion injury during delayed replantation.

    Release date:2016-09-01 11:18 Export PDF Favorites Scan
  • Present view in understanding of polypoidal choroidal vasculopathy

    Polypoidal choroidal vasculopathy (PCV) is originally defined as a separate disease, but with the development of imaging techniques, it has now been included in the spectrum of neovascularization. In the Asian population, the prevalence of PCV is high, and with the deepening of clinical studies, the pathological characteristics, pathogenesis and clinical manifestations of PCV have been more deeply understood. Through dynamic observation and histopathological study of PCV lesions during operation, it can be confirmed that the lesions are mainly located between the retinal pigment epithelium and the Bruch membrane, rather than originating from the choroidal circulation, which is of great significance for understanding the origin and natural course of PCV. It is worth noting that although a theoretical bridge has been established between age-related macular degeneration (AMD)/PCV, there is a lack of intuitive clinical data on the ultrastructural and molecular manifestations of the cells/stroma in the local lesions of the eye, especially the progression of AMD/PCV from early/middle stage to exudative stage. It is precisely because of this that highly attractive research topics and exploration space are proposed for the future.

    Release date:2024-03-06 03:23 Export PDF Favorites Scan
  • Construction of provincial health emergency team in Sichuan province

    Sichuan provincial health emergency team has completed a number of domestic emergencies, as well as the emergency medical rescue of the Nepal earthquake, since constructured. It established a great industry image, moreover, the people’s health and safety of life were ensured. This paper summarized the experience of Sichuan provincial health emergency team construction, to provide scientific evidence of optimizing health emergency team construction in China.

    Release date:2022-04-28 09:46 Export PDF Favorites Scan
  • Research on exudate segmentation method for retinal fundus images based on deep learning

    Objective To automatically segment diabetic retinal exudation features from deep learning color fundus images. Methods An applied study. The method of this study is based on the U-shaped network model of the Indian Diabetic Retinopathy Image Dataset (IDRID) dataset, introduces deep residual convolution into the encoding and decoding stages, which can effectively extract seepage depth features, solve overfitting and feature interference problems, and improve the model's feature expression ability and lightweight performance. In addition, by introducing an improved context extraction module, the model can capture a wider range of feature information, enhance the perception ability of retinal lesions, and perform excellently in capturing small details and blurred edges. Finally, the introduction of convolutional triple attention mechanism allows the model to automatically learn feature weights, focus on important features, and extract useful information from multiple scales. Accuracy, recall, Dice coefficient, accuracy and sensitivity were used to evaluate the ability of the model to detect and segment the automatic retinal exudation features of diabetic patients in color fundus images. Results After applying this method, the accuracy, recall, dice coefficient, accuracy and sensitivity of the improved model on the IDRID dataset reached 81.56%, 99.54%, 69.32%, 65.36% and 78.33%, respectively. Compared with the original model, the accuracy and Dice index of the improved model are increased by 2.35% , 3.35% respectively. Conclusion The segmentation method based on U-shaped network can automatically detect and segment the retinal exudation features of fundus images of diabetic patients, which is of great significance for assisting doctors to diagnose diseases more accurately.

    Release date:2024-07-16 02:36 Export PDF Favorites Scan
  • Whole Constructive Conception and Basic Organization Structure in Multi-Disciplinary Team for Colorectal Cancer

    Objective To explore the whole constructive conception and organization structure strategy of multi-disciplinary team (MDT) for colorectal cancer (CRC). Methods Combined the characteristics of large public hospital, with recognized treatment pathway in MDT for CRC and the way of medical project construction, MDT for CRC project team summarized a system of MDT for CRC of West China Hospital (MDT-CRC-WCH) by own characteristics and subject feature. Results MDT for CRC summarized the 5 basic characteristics about profession, classification, interaction, optimization and fast. The project has the core competencies: system new operation types for colorectal cancer and volunteer culture. By the matrix organization structure, MDT set the main departments: database team, follow-up team, nursing team and public team. Conclusion With effective MDT whole construction and suitable organization structure, MDT will develop in long time.

    Release date:2016-09-08 11:49 Export PDF Favorites Scan
  • Histological properties of autogenous hamstring grafts after anterior cruciate ligament reconstruction

    ObjectiveTo investigate the histological characteristics of autogenous hamstring grafts after anterior cruciate ligament (ACL) reconstruction.MethodsThe patients who underwent arthroscopic single-bundle ACL reconstruction with autogenous hamstring tendons and were followed up at least 4 years and also underwent second-look arthroscopy between March 2017 and December 2017 and met the selection criteria were considered for enrollment. Graft quality under arthroscopy was evaluated as good remodeling group (GRG, the total scores were 4-6) and poor remodeling group (PRG, the total scores were 1-3) according to synovial and vascular coverage, the apparent tension of the grafts, the thickness and retear of the grafts. During the second-look arthroscopic procedures, ACL graft biopsies were performed. Normal ACL tissues harvested from the patients under 60 years old who underwent total knee arthroplasty were designated as normal controls. Graft vascularity, cellular morphology, cellular metabolism, and collagen fibril distribution were analyzed.ResultsThe 18 specimens (11 cases of GRG group and 7 cases of PRG group) and 9 native ACL biopsied tissue sample were enrolled into the study. Arthroscopy scores were 2-6 (mean, 4.7). The biology under light microscopy of GRG group was similar to that of native ACL in control group. There was no significant difference in the scores of graft vascularity and cellular morphology between GRG group and control group (P>0.05), while PRG group was significantly lower than the other two groups (P<0.05). Transmission electron microscope evaluation showed that GRG group and control group had better collagen fibril distribution and lower levels of cellular metabolism than PRG group (P<0.05). There was no significant difference in cellular metabolism between GRG and control groups (P>0.05), while collagen fibril distribution score of GRG group was significantly lower than that of control group (P<0.05).ConclusionWhile good remodeling grafts under arthroscopy in histological maturation period was proved to be more similar to normal ACL on ultrastructure properties under light and electron microscope, ultra structural differences regarding collagen fibril distribution still persist.

    Release date:2018-07-12 06:19 Export PDF Favorites Scan
  • Observation on retinal ultrastructures of the human fetus at the gestational age of 9 months

    Objective To observe the retinal ultrastructure of the human fetal at the age of 9 months, and to investigate the clinical significance of the observation on retinal neuron development during the prenatal period.Methods Four human fetal eyes of 2 fetus at the gestational age of 9 months, including 1 at 35 and the other at 36 weeks, were obtained after termination of pregnancy due to trauma. The gestational ages of the fetus were estimated according to both last menstrual period (LMP) of the pregnant women and the weight/crownheel length of fetus at the delivery. From each eyeball, 4 pieces of retina at the posterior pole were obtained and observed after specimens handling according to the procedure of routine electron microscopy. Eight pieces of retina which were randomly selected from total of 16 pieces of retina in each group were processed and observed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Permissions from pregnant women and family members were guaranteed.Results At the gestational age of 9 months, the outer nuclear layer of fetal retina contained 5 to 6 layers of photoreceptor cells (PRC), and sphericallike membrane structures were found outside of the outer limiting membrane (OLM). Among many tightaligned inner segments of PRCs there was zonula adherens of OLM, mitochondrias at inner side of OLM, and cilium at outer side of OLM. Outer segment of PRCs were short and contained a few irregularly arranged disc membrane. Some PRC had a multishaped nucleus in which equal amount of euchromatin and heterochromatin. There were only few and thin axon branches from photoreceptor cells, and very few axons contacted with inner nuclear layer (INL) and no typical synapse was found. The INL contained 4 to 5 layers of cell bodies, in which many cellular nuclear had uneven density of euchromatin and heterochromatin; some were lobulated nucleus with clear karyotheca. In inner plexiform layer (IPL), the nerve cells had small branches, and only little connection among the synapses and few synapse structures were found. Although not many retinal ganglion cells (RGC) existed,RGC had both intact cell membrane and some rough endoplasmic reticulum (RER).The karyotheca of RGC had double-layers structures, and the nucleus was mainly consisted of euchromatin. Internal limiting membrane (ILM) had doublelayer membrane structures, and the wellarranged nerve fiber layer was located at the outer side of ILM, with some micropores on the surface. Conclusions At the gestational age of 9 months, all layers of the human retinal has been formed, but some cell structure and cell connections are not yet mature, suggesting that at this time of period, human retina is still at an important stage of developing and remodeling.

    Release date:2016-09-02 05:43 Export PDF Favorites Scan
  • EFFECTS OF HEPATIC ARTERY ISCHEMIA ON ULTRASTRUCTURE OF LIVER AND BILIARY DUCT IN CANINE AUTO-TRANSPLANATION

    A simple model of canine auto-trasplantation of liver was set up by ourselves, and the effects of hepatic artery ischemia (HAI) on ultrastructure of liver and biliary duct transplanted were observed. The results showed that the liver and biliary cells swelled slightly, mitochondrial matrix was loose and ridges were vague just often perfusion. Afte HAI for 3 hours the edema of hepatic and biliary cells aggravated cytoplasm was loose, mitochondria enlarged and partly vacuolar degenerated, ridges broke or disappeared, flocculent focal densites was seen in the matrix, endoplasmic retculum distended obviously, and the ribosome depolymerizated. So we consider that HAI causes obvious damage to hepatic and biliary cells. These indicate that HAI is one of the important factors of complication after liver transplantation, especially some biliary complications.

    Release date:2016-08-29 03:44 Export PDF Favorites Scan
  • Ultrastructural changes and expression of basicfibroblast growth factor of diabetic retinopathy

    ObjectiveTo investigate relationship between ultrastructural changes and expression of basic fibroblast growth factor of diabetic retinopathy in rats.MethodsDiabetes was induced in rats with a single injection of streptozotocin (STZ) and divided into normal control group and 1- , 3- and 5- month diabetes group. The paraffin slide was observed by in-situ hybridization and immunohistochemistry, and retinal ultrastructure was examined by transmission electron microscopy.ResultsNo change of retinal ultrastructure was found in the control group. Different degrees of ultrastructure lesion were found in 1-month diabetic rats with fragmental increase of thickness of basement membrane, swelling of endothelial cells and obvions fingerlike processes in the capillary cavity, disconcentration of heterochromatin both in endothelium and pericyte, and swelling and degeneration of mitochondrion. The edema of endothelial cells of 3-month diabetic rats was more serious than that of 1month ones, and the capillary cavity was nearly occluded. In 5-month diabetic rats, the basement membrane was unevenly thickened, or obviously split. The positive rate of in-situ hybridization in 3-month diabetic rats was 77.8% while the positive rate of immunohistochemical stain was 55.6%, which increased to 88.9% in 5-month diabetic rats.ConclusionsThe occurrence of the ultrastructural changes in STZ rats with diabetic retinopathy is earlier than that of the expression of bFGF.(Chin J Ocul Fundus Dis, 2003,19:348-351)

    Release date:2016-09-02 06:00 Export PDF Favorites Scan
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