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991.
目的:为桡侧腕短伸肌腱部分移位修复第一腕掌关节脱位提供解剖学依据。方法:30侧成人上肢标本,将桡侧腕短伸肌腱分为上、中、下3部分,进行形态学测量。结果:桡侧腕短伸肌腱长度为(15.3±1.9)cm(10~22.5cm),其宽度:上段为(15.4±5.2)mm(5.3~23.8mm),中段(10.0±3.0)mm(4.2~18.5mm),下段(5.5±0.6)mm(3.7~9.6mm);厚度:上段为(0.6±0.3)mm(0.1~1.4mm),中段为(1.8±0.7)mm(0.7~3.0mm),下段为(2.1±1.2)mm(0.8~3.1mm)。结论:桡侧腕短伸肌腱部分转位有足够的长度以修复第一腕掌关节脱位。  相似文献   
992.
The present study was to investigate and evaluate the dynamic changes of calcium homeostasis of soleus muscle spindle for the exploration of the potential mechanisms of muscle spindle degeneration induced by hindlimb unloading. We systematically observed the changes in immunoreactivity of calbindin D28K (CaBP-D28K), intracellular resting calcium in intrafusal fibers of soleus muscle spindle, and the responsiveness of muscle spindles to ramp-and-hold stretches after short- and long-term (3, 7, 14 d) hindlimb unloading. The immunoreactivity of CaBP-D28K started to decrease after 7-d hindlimb unloading, while its decrease was obviously different compared with the control group 14 d following the hindlimb unloading. The resting calcium concentration was increased significantly at 3 d, and reached the peak level 14 d after the hindlimb unloading. The responsiveness of muscle spindles, assessed by investigating Index3-L2, Index3-L3, and Index5, to ramp-and-hold stretches started to decrease during the period of 7-d hindlimb unloading. All Indexs, in particular Index3-L3 and Index5, were significantly decreased at 14 d after the hindlimb unloading. The data suggest the disturbance of calcium homeostasis in intrafusal fibers during the exposure to hindlimb unloading might gradually influence the structure and function of muscle spindles.  相似文献   
993.
994.
A 69-year-old man presented with cough, shortness of breath, and fatigue. He was initially treated for allergies and then for pulmonary embolism. Radiologically, a tumor mass was found to occlude the right pulmonary artery and involve the pulmonary trunk. A right pneumonectomy was performed. Histologically, a cellular malignant spindle and epithelioid tumor with areas of necrosis and brisk mitotic activity was seen. In some areas, the tumor appeared to form vascular channels. Focal osteosarcomatous differentiation was present. Immunohistochemical studies were performed including vimentin, smooth muscle actin, desmin, CD31, CD34, S100, and pan-cytokeratin. The tumor cells were positive for CD31 and vimentin and negative for pan-cytokeratin, CD34, and S100. Two months after surgery, the patient was alive and well.  相似文献   
995.

Background  

The purinergic receptor P2x7 is expressed on myeloid cells as well as on CNS glial cells, and P2x7 activation has been shown to increase both glial and T-cell activation. These properties suggest a role in the development of autoimmune disease including multiple sclerosis.  相似文献   
996.
The aim of this study is to determine in indigenous Chinese ethnic groups the frequencies of the chemokine (SDF1 3'A) and chemokine receptors (CCR5 delta32, CCR5 m303, and CCR2b 64I) HIV-1/AIDS restriction alleles. The study includes two cohorts; the first comprised 3165 indigenous healthy subjects representing eight ethnic groups: Han (n = 1406), Uygur (n = 316), Mongolia (n = 134), Hui (n = 386), Tibetan (n = 330), Zhuang (n = 378), Dai (n = 101), and Jingbo (n =114). The second cohort consisted of 330 HIV-1-infected (86 subjects infected by sexual transmission and 198 subjects infected by HIV-1-contaminated blood or by sharing injection equipment; the remaining 46 subjects said nothing about HIV-1 transmission) and 474 HIV-1-uninfected Han Chinese belonging to one of two HIV-1 high-risk groups: intravenous drug users (n = 215) and individuals with sexually transmitted diseases (n = 259). Genotypes for the four genes were obtained using PCR (CCR5 delta32) or PCR-restriction fragment length polymorphism. Randomly selected amplified PCR products were further confirmed by direct DNA sequencing. The variant allele frequencies were determined to be 0% to 3.48% for CCR5 delta32, 0% for CCR5 m303, 16.23% to 28.79% for CCR2b 64I, and 17.70% to 27.76% for SDF1 3'A in Chinese healthy individuals from eight ethnic groups. These findings show that allele frequencies differ among the eight Chinese ethnic groups for CCR5 delta32, CCR2b 64I, and SDF1 3'A and that the CCR5 m303 and CCR5 delta32 mutant alleles were absent or infrequent in Chinese, which may be helpful for studies of specific anti-HIV-1 vaccine trials and coreceptor inhibitor drug targets in Chinese populations. Furthermore, we observed no significant differences in allele or genotypic frequencies between HIV-1-infected and HIV-1-uninfected groups from the Han ethnic group. Our finding is the first reporting that there is likely no effect of the examined polymorphisms in our study on HIV-1 transmission in the Chinese Han population, However, the genetic effects of these and other AIDS-modifying polymorphisms on the pathogenesis and clinical outcome of HIV-1/AIDS diseases is under investigation in Chinese populations.  相似文献   
997.
Chang CH  Liu HC  Lin CC  Chou CH  Lin FH 《Biomaterials》2003,24(26):4853-4858
The mechanism by which the cell synthesizes and secretes extracellular matrix (ECM) and is, in turn, regulated by the ECM is termed dynamic reciprocity. The aim of the present work was to produce a gelatin/chondoitin-6-sulfate/hyaluronan tri-copolymer to mimic natural cartilage matrix for use as a scaffold for cartilage tissue engineering. The scaffold produced had a uniform pore size of about 180 microm and adequate porosity of 75%. Porcine chondrocytes were seeded onto the tri-copolymer scaffold and cultured in Petri dishes or spinner flasks for 2, 3, 4, or 5 weeks. Chondrocytes were uniformly distributed in the scaffold in the spinner flask cultures, but less so in the Petri dish cultures. Secretion of ECM was found under histology examination. In spinner flask cultures, chondrocytes retained their phenotype for at least 5 weeks, as shown immunohistochemically, and synthesized type II collagen. These results show that gelatin/chondroitin sulfate/hyaluronan tri-copolymer has potential for use as a cartilage tissue engineering scaffold.  相似文献   
998.
The ospC genes of 20 southern Borrelia strains were sequenced. The strains consisted of B. burgdorferi sensu stricto, B. andersonii, B. bissettii, one undescribed genospecies, MI-8, and one probably new Borrelia species, TXW-1. A high degree of similarity exists between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Lateral transfers of the ospC gene probably occurred between B. burgdorferi sensu stricto and B. bissettii and between B. bissettii and B. andersonii. Internal gene recombination appears to occur among them. The highest degree of genetic diversity among them was observed in the two variable domains (V1 and V2), semivariable domain (SV), and the species-specific epitopes (between amino acids 28 and 31). Differences in ospC sequences among southern strains reflect diversity at the strain and genospecies levels. MI-8, which was recognized as an undescribed genospecies in our previous reports, remains distinguishable in our current analysis of ospC genes and is distinct from B. burgdorferi sensu stricto. Interestingly, another undescribed southern isolate, TXW-1, was not amplified under various PCR conditions. Compared to European B. burgdorferi sensu stricto strains, American B. burgdorferi sensu stricto strains show greater genetic heterogeneity. Southern B. burgdorferi sensu stricto, B. andersonii, and B. bissettii isolates were intermixed with each other in the phylogenetic trees. In the derived trees in our work, at least one southeastern strain of B. burgdorferi, MI-2, most closely aligns with a so-called invasive cluster that possesses many proven human-invasive strains. Transmission experiments show that MI-2 and the strains in this group of southern spirochetes are able to infect mice and hamsters and that the typical vector of Lyme disease, Ixodes scapularis, can acquire the spirochetes from infected mammals. Currently, strain MI-2 appears to be the only southern isolate among the 20 we analyzed that clusters with an OspC invasive group and thus might be invasive for humans.  相似文献   
999.
Heroin dependence is resulted from the interaction between multiple genetic and environmental factors. Subjective craving is considered to be a central phenomenon, which contributes to the continuation of drug use in active abuser and the occurrence of relapse in detoxified abusers. Dopamine pathway has been implicated in the cue-elicited craving for a variety of addictive substances. The objective of this study was to test the hypothesis that heroin addicts carrying specific variants in dopamine-related genes would have higher levels of craving following exposure to a heroin-related cue. Craving induced by a series of exposure to heroin-related cue was assessed in a cohort of Chinese heroin abuser (n = 420) recruited from natural abstinence center at Shanghai. Significantly stronger cue-elicited heroin craving was found in individuals carrying D2 dopamine receptor gene (DRD2) TaqI RFLP A1 allele than the non-carriers (P < 0.001). Furthermore, we did not observed significant association of cue-elicited craving with the nine-repeat allelic variants in dopamine transporter gene (DAT) SLC6A3 and with the dinucleotide repeat polymorphism (DRP) 148bp allele in D5 dopamine receptor gene (DRD5). The results of our study suggest that human dopamine pathway be involved in cue-induced heroin craving, and indicate a potential genetic risk factor for persistent heroin behavior and relapse.  相似文献   
1000.
BACKGROUND: Systemic anaphylaxis after the ingestion of mite-contaminated food has rarely been reported. OBJECTIVE: To describe an 8-year-old boy in whom systemic anaphylaxis developed shortly after the ingestion of pancakes prepared with commercial pancake flour. METHODS: The patient underwent skin prick testing for house dust mites and with uncontaminated and mite-contaminated pancake flour. Specific IgE for mites and the main ingredients of the pancake flour were also evaluated, with titers for Der p 1, Der f 1, and Blo t 5 quantitated using immunochemical methods. A sample of pancake flour was examined microscopically for mites. RESULTS: The patient had positive skin prick test results to contaminated pancake flour extract (1 g/5 mL), Dermatophagoides pteronyssinus, and Dermatophagoides farinae but a negative skin test response to uncontaminated pancake flour. The patient's serum specific IgE analysis was positive for antibodies to dust and storage mite allergens. There was no response, however, to the main ingredients of the pancake mix. Microscopic examination of the pancake flour revealed the storage mite Blomia freemani. Using an immunochemical assay, we found that the contaminated flour contained 5.4 microg/g of the allergen Blo t 5 but no Der p 1 or Der f 1. CONCLUSIONS: This patient's anaphylactic episode was the result of ingestion of the storage mite B. freemani. To our knowledge, this is the first reported systemic hypersensitivity reaction caused by this mite anywhere in the world.  相似文献   
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