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51.
老年2型糖尿病患者胰岛素抵抗相关指标的检测和意义 总被引:1,自引:1,他引:0
目的:探讨老年2型糖尿病胰岛素抵抗(IR)及其相关性,为老年2型糖尿病的合理防治提供临床依据。方法:选择120例老年2型糖尿病患者,按胰岛素敏感指数(HOMA)胰岛素抵抗(HOMA-IR)50百分位点将患者分为两组:胰岛素相对敏感组(HOMA-IR<3.56)和胰岛素相对抵抗组(HOMA-IR≥3.56),比较体重指数(BMI)、腰/臀比(WHR)、血压、血生化学检查等指标。用年龄>40岁,<60岁的2型糖尿病患者做对照组。结果:两组老年患者在年龄、性别、舒张压、空腹血糖、胆固醇、高密度脂蛋白、糖化血红蛋白、HOMA胰岛β细胞功能方面无差异;但BMI、WHR、收缩压、甘油三脂、空腹胰岛素、HOMA-IR差异具有显著性。多线性回归分析后,只有腰/臀比、收缩压、甘油三脂、HOMA-IR存在统计学差异。老年患者与对照组相比,IR发生率明显增加,且两者腰/臀比、收缩压、甘油三脂方面也差异显著。结论:IR与老年2型糖尿病密切相关,是临床防治糖尿病的重要靶点。 相似文献
52.
膀胱癌组织P-gp,GST-π和TOPO-Ⅱ表达评估灌注化疗 总被引:1,自引:0,他引:1
目的:探讨膀胱癌的多药耐药性(MDR),指导灌注化疗用药。方法:采用免疫组化法检测44例膀胱癌病理标本中P-糖蛋白(P-gp)、谷胱肽S转移酶(GST-π)和拓扑异构酶(TOPO—Ⅱ)的表达,评估肿瘤耐药谱。结果:①P-gp检测显示,54.5%的病例对阿毒索、丝裂毒索、长春新碱等抗生索类和生物碱类抗癌药高耐药。②GST-π检测显示仅34.1%的病例对顺铂、环磷酰胺等高耐药,而反有56.8%的病例对该类药无耐药或低度耐药。③TOPO-Ⅱ检测显示对阿霉索、柔红毒索、VP16等TOPO-Ⅱ抑制剂类抗癌药,仅13.6%的病例高度耐药,29.5%中度耐药。56.8%低度耐药。结论:检测膀胱癌MDR,了解多药耐药谱,可指导灌注化疗用药。 相似文献
53.
生物衍生骨复合骨髓基质干细胞修复山羊胫骨缺损的血管化研究 总被引:10,自引:5,他引:5
目的研究生物衍生骨与骨髓基质干细胞(marrow stromal stem cells, MSCs)复合修复山羊胫骨缺损的血管化过程,了解其修复长段管状负重骨缺损的血管化情况. 方法制备生物衍生骨作为支架材料,培养、诱导MSCs作为种子细胞,二者在体外复合构建组织工程骨.20只山羊双侧胫骨中段制备成20 mm长的骨-骨膜缺损模型,采取自身左右侧对照,实验侧(右侧)缺损处植入组织工程骨,对照侧(左侧)植入单纯支架材料,采用钢板内固定.术后2、4、6及8周用墨汁灌注透明标本及血管面积图像分析方法观察血管化过程,组织学观察血管形成及成骨情况. 结果术后2、4周,实验侧血管形成较对照侧少(P<0.05);术后8周,两侧均完全血管化,差异无统计学意义(P>0.05).实验侧于术后6、8周新骨形成逐渐增加,材料降解吸收较对照组快;对照侧术后8周材料孔隙内仍无明显新骨形成. 结论生物衍生骨作为骨组织工程的支架材料,能够较快发生血管化;组织工程骨成骨能力较单纯支架材料强. 相似文献
54.
Osteoclastogenesis in the nonadherent cell population of human bone marrow is inhibited by rhBMP-2 alone or together with rhVEGF. 总被引:1,自引:0,他引:1
During bone development and repair, angiogenesis, osteogenesis, and bone remodeling are closely associated processes that share some common mediators. In the present study nonadherent human bone marrow mononuclear cells under the induction of sRANKL and M-CSF, differentiated into osteoclasts with TRAP-positive staining, VNR expression, and Ca-P resorptive activity. The effects of various combinations of rhBMP-2 (0, 3, 30, and 300 ng/mL) and rhVEGF (0 and 25 ng/mL) on osteoclastogenesis potentials were examined in this experimental system. The percentages of TRAP-positive multiple nucleated cells represent osteoclast differentiation potential, and the percentages of resorptive areas in the Ca-P coated plates resemble osteoclast resorption capability. The presence of rhBMP-2 at 30 and 300 ng/mL showed inhibitory effects on osteoclast differentiation and their resorptive capability in the human osteoclast culture system. rhVEGF (25 ng/mL) enhanced the resorptive function of osteoclast whenever it was used alone or combined with 3 ng/mL rhBMP-2. However, rhVEGF-induced resorptive function was inhibited by 30 ng/mL and 300 ng/mL rhBMP-2 in a dose-dependent manner. Statistical analysis demonstrated that an interactive effect exists between rhBMP-2 and rhVEGF on human osteoclastogenesis. These findings suggested that an interactive regulation may exist between BMPs and VEGF signaling pathways during osteoclastogenesis; exact mechanisms are yet to be elucidated. 相似文献
55.
56.
大中学生预防艾滋病生活技能需求 总被引:4,自引:3,他引:1
目的了解我国学生对学校预防艾滋病教育中生活技能的需求情况,为今后开展以生活技能为基础的预防艾滋病教育提供依据。方法对北京市5所初中3、所高中和2所大学的1207名学生进行问卷调查。结果无论初中、高中还是大学生,多数学生都认为这些生活技能要素在开展预防艾滋病教育中能够起到重要的作用。不同学段学生对9类技能的认知重要程度不同,初中生认为认识和解决问题能力最重要,高中生认为创造性思维能力最重要,大学生认为批判性思维能力最重要。结论根据学生年龄有所侧重地开展以生活技能为基础的学校预防艾滋病教育十分重要。 相似文献
57.
A case of beta-thalassemia with an unusual focus of extramedullary hematopoiesis is reported. The presacral area was involved producing a significant mass effect on the rectum. 相似文献
58.
Biomechanics of the golf swing in players with pathologic conditions of the forearm, wrist, and hand
Golf is an activity generally stressful to the hands and wrists and particularly can produce increasing symptoms in players with underlying problems such as hand and wrist arthritis or tendinitis. The purpose of this study was to quantitate wrist motion and club head/ball impact force in subjects with pathologic conditions of the hand, wrist, or forearm, within a laboratory environment. A regular straight-handled golf club was compared to a new BioCurve handle design that has a 19 degrees ulnar bend. We measured and compared the effect of the two grips on wrist motion, club head velocity, ball impact force, ball impact location, and isometric torsional strength in 20 subjects who had a variety of upper extremity disorders. This data was then compared to data collected in an identical fashion from golfers without such conditions. The results of our study show that there were no differences related to club handle design on impact force or impact location, club head velocity, or club head path and face angle. Wrist kinematic differences were minimal between handle designs. The differences that were significant (P less than 0.05) centered around the decreased ulnar deviation of the left hand that resulted when subjects used the BioCurve handle design, which also allowed greater resistance to torque than the straight grip club. In addition to collecting objective data, we asked subjects for their opinions of the two grips. As a whole, the normal group and the group with pathologic conditions noted more comfort, improved grip, and less shock transmission with the BioCurve handle. 相似文献
59.
Forty of the 87 patients with microinvasive carcinoma (MIC) of the uterine cervix who underwent surgery were diagnosed colposcopically and the results were compared with the cytological and histological diagnoses. The cytology showed preinvasive carcinoma in 20 (50.0%) patients and invasive carcinoma in 19 (47.5%) patients. A correct colposcopic diagnosis was made in nine (22.5%) patients as having microinvasive carcinoma, 21 (52.5%) patients preinvasive carcinoma and eight (20%) patients invasive carcinoma, to sum up accuracy rate as 32.1%. The abnormalities most commonly observed in colposcopy were mosaic, punctuation and white epithelium. In microinvasive carcinoma, the triad co-existed in 43% of the patients. Atypical vessels, characteristic of invasion, were found in only one third of the patients. Microinvasion, therefore, may not be evident on colposcopy alone. It is therefore necessary to apply cone biopsy, prior to definite therapy, to make an accurate assessment of the maximum depth and extent of the invasion prior to definitive therapy. 相似文献
60.
J L Li J L Chen M H Ouyang S Chao Y B Peng L X Lin W S Chang Y J Li 《Journal of immunological methods》1991,142(1):15-20
Anti-idiotypic antibodies are powerful reagents for the study of immunoregulation, and have potential interest as vaccines against tumors and infectious diseases. Three immunization strategies for the production of rat monoclonal anti-idiotope antibodies have been compared in this paper. Male Wistar rats were immunized i.p. and at multiple subcutaneous sites with 750 micrograms of purified monoclonal antibody against Plasmodium falciparum for three times and subsequently boosted by (1) intraperitoneal injection with 750 micrograms of the immunogen, (2) intravenous inoculation with 400 micrograms of the IgG, and (3) intrasplenic immunization with 200 micrograms of the idiotype. With the intraperitoneal boost method, the frequency of hybrids with anti-idiotope activity was 0.3-0.9% with 62.8-85.2% of the seeded wells containing hybrids. In the intravenous boost group, the percentage of hybrids demonstrating anti-idiotope activity increased to 11.0-13.3% with 80.2-97.9% of the hybrid efficiency. When immunized by the intrasplenic boost route, the frequency of anti-idiotope hybrids generated rose to 12.9-16.4% with 82.3-96.6% of the hybrid efficiency. There was no obvious effect of the boost immunizing methods on the generation of rat monoclonal anti-mouse IgG antibodies. These results indicated that the multiple-site immunization followed by intravenous or intrasplenic boost injection was an appropriate immunizing method for the production of monoclonal anti-idiotope antibodies. 相似文献