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排序方式: 共有1048条查询结果,搜索用时 500 毫秒
1.
肩、肘关节外科新进展 总被引:1,自引:0,他引:1
肩关节(Shoulder)
旋转袖(Rotator Cuff)
基础研究(Basic Science)
Zuckerman讨论了软骨诱导形态发生蛋白-2(cartilagederived morphogenetic protein-2,CDMP-2)的早期工作。在鼠肌腱修复中,4周时CDMP-2治疗组的修复强度高于未治疗组。Dines讨论了关于血小板衍生生长因子(platelet—derived growth factor,PDGF)和胰岛素样生长因子-1(insulin-like growth factor-1,IGF-1)最初的研究观察。 相似文献
2.
7-甲氧基-4′-羟基-3′-二乙胺甲基异黄酮(MHDF)对大鼠血流动力学和主动脉的作用 总被引:2,自引:0,他引:2
本实验观察了MHDF对整体大鼠血流动力学和离体大鼠胸主动脉的作用。结果表明iv MHDF(3~12.8 mg/kg)能降低大鼠左心室±dp/dtmax,Vmax,Vpm和LVSP,延长T-dp/dtmax,减慢心率。MHDF还能舒张大鼠胸主动脉,ED50为6.5×10-6mol/L;非竞争拮抗NA和CaCl2致主脉收缩,pD2′为3.11±0.21和3.73±0.07;抑制高K+致主动脉收缩,IC50为1.76×10-5mol/L。提示MHDF对血管的作用与α受体阻断剂不同,而可能与钙拮抗有关。 相似文献
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STUDY OBJECTIVE: To test the hypothesis that induced human graafian follicles consist of different steroidogenic cell types on the basis of their light scatter characteristics as determined by flow cytometry. DESIGN: Cross-sectional, observational study. SETTING: Flow cytometry laboratory. PATIENTS: Thirty-six follicular aspirates from nine consecutive patients undergoing in vitro fertilization for tubal factor infertility were evaluated. RESULTS: Two distinct luteal cell populations were recovered. Both populations were positive by Oil Red O staining, suggesting the presence of intracellular lipid. Neither population stained positively for the presence of HLe-1/CD45, an antigen present on all human leukocytes. CONCLUSIONS: Cellular heterogeneity exists within the granulosa cell compartment. 相似文献
5.
Abstract: Adequate venous access is an essential component of therapeutic plasma exchange (TPEX). The simplest kind of venous access is venipuncture of antecubital veins, but this technique may be limited by venous size or scarring following the procedure, requiring the placement of a specialized vascular access device (VAD). VADs provide reliable central venous access and may remain in place for several weeks or months, depending on the VAD and the venous site chosen. Their use, however, is potentially limited by the risk of complications. We discuss indications for insertion, choice of catheter and access site, and complications of VAD placement for TPEX. 相似文献
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Margalith M Chatlynne LG Fuchs E Owen C Lee CR Yermiyahu T Whitman JE Ablashi DV 《Journal of acquired immune deficiency syndromes (1999)》2003,34(5):500-505
OBJECTIVE: To compare the prevalence of antibodies to human herpesvirus 8 (HHV-8) or Kaposi sarcoma-associated herpesvirus among Israeli and Ethiopian subjects. METHODS: Serum samples were obtained from 98 Israeli Jewish students aged 18-30 years, 100 HIV-1-seronegative Ethiopian immigrants to Israel of the same age, and 100 HIV-1-seronegative Ethiopian children 1-12 years old upon their arrival in southern Israel. Plasma samples were obtained from 3 hospitalized patients with multicentric Castleman disease (MCD) as positive controls. All serum samples were tested for antibodies to both latent and lytic antigens. Antibodies to the lytic antigens and the latency-associated nuclear antigen (LANA) of HHV-8 were detected by enzyme linked immunosorbent assay and by immunofluorescence assay. HHV-8 DNA from serum or plasma samples was detected by polymerase chain reaction analysis. RESULTS: Antibodies to HHV-8 LANA were detected in 2.9% of the Israeli subjects aged 18-30 years and in 26% of the Ethiopian subjects from both age groups tested. Antibodies to the lytic antigens were detected in all 3 MCD patients, in 4% of the Ethiopian children, and in 2% of the 18- to 30-year-old Ethiopians. No antibodies to the lytic antigens were detected in the Israeli students. HHV-8 DNA was detected in all 3 MCD patients and in 2 of 4 of the Ethiopian children positive for the lytic antigens. CONCLUSIONS: HHV-8 is highly prevalent in Ethiopian immigrants to Israel as compared with Israeli students. Antibodies to HHV-8 in Ethiopia are acquired before puberty. The results of this study indicate the association of HHV-8 with MCD, as has been documented by many other researchers. 相似文献
8.
Exogenous interferon-gamma enhances atherosclerosis in apolipoprotein E-/- mice 总被引:11,自引:0,他引:11 下载免费PDF全文
A role for interferon-gamma (IFN-gamma) has been implied in the atherogenic process. To determine whether exogenously administered IFN-gamma exerts an effect on the development of atherosclerosis, we intraperitoneally administered either recombinant IFN-gamma (100 U/g body weight) or phosphate buffered saline daily for 30 days to atherosclerosis-susceptible apolipoprotein E-/- mice (16-week-old male mice, n = 11 per group) fed a normal diet. Atherosclerotic lesion size was quantified in the ascending aorta. The number of T lymphocytes and major histocompatibility complex (MHC) class II-positive cells within lesions were also quantified in this region. IFN-gamma administration reduced serum cholesterol concentrations by 15% (P = 0.02). For both groups, the majority of cholesterol was present in very low density lipoproteins, which were modestly reduced in mice receiving IFN-gamma. Despite the decrease in serum cholesterol concentrations, IFN-gamma injections significantly increased lesion size twofold compared to controls (119,980 +/- 18, 536 vs. 59,396 +/- 20,017 micrometer(2); P = 0.038). IFN-gamma also significantly increased the mean number of T lymphocytes (19 +/- 4 vs. 7 +/- 1 cells; P = 0.03) and MHC class II-positive cells (10 +/- 3 vs. 3 +/- 1 cells; P = 0.04) within lesions. These data lend further support to a pro-atherogenic role of IFN-gamma. 相似文献
9.
Whitman MC Strohmaier J O'Boyle K Tingem JM Wilkinson Y Goldstein J Chen T Brorson K Brunswick M Kozlowski S 《Molecular immunology》2000,37(3-4):141-149
The MHC class I molecule plays a crucial role in cytotoxic lymphocyte function. The heavy chain of the MHC class I molecule can form many non-covalent interactions with other molecules on multiple domains and surfaces. We have generated an isolated alpha3 domain of a murine MHC class I molecule and evaluated the contribution of this domain to binding with the MHC class I light chain, beta2m, and CD8. The alpha3 domain binds beta2m at a thousand-fold higher concentration than the whole MHC, and binds CD8alphaalpha with a dependence on the alpha3 CD loop. Our results are relevant for models of MHC folding and CD8-MHC function. The study of individual domains of complex molecules is an important strategy for understanding their dynamic structure and function. 相似文献
10.
Whitman SA Wacker MJ Richmond SR Godard MP 《Pflügers Archiv : European journal of physiology》2005,450(6):437-446
The primary mechanism that contributes to decreasing skeletal muscle strength and size with healthy aging is not presently known. This study examined the contribution of the ubiquitin–proteasome pathway and apoptosis to skeletal muscle wasting in older adults (n = 21; mean age = 72.76 ± 8.31 years) and young controls (n = 21; mean age = 21.48 ± 2.93 years). Subjects underwent a percutaneous muscle biopsy of the vastus lateralis to determine: (1) ubiquitin ligase gene expression (MAFbx and MuRF1); (2) frequency of apoptosis; and (3) individual fiber type and cross-sectional area. In addition, a whole muscle strength test was also performed. A one-way ANOVA revealed significant increases in the number of positive TUNEL cells in older adults (87%; p < 0.05), although no significant increase in caspase-3/7 activity was detected. Additionally, ubiquitin ligase gene expression, individual muscle fiber type and CSA were not different between old and young subjects. Muscle strength was also significantly lower in old compared to young subjects (p < 0.05). In conclusion, this study indicates a preferential role for apoptosis contributing to decreases in muscle function with age. 相似文献