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101.
R. Rybar P. Markova Z. Veznik L. Faldikova M. Kunetkova A. Zajicova V. Kopecka & J. Rubes 《Andrologia》2009,41(3):141-149
Damage to the genetic component of spermatozoa seems to play the main role in a majority of cases where current approaches fail to reveal the specific cause of male infertility. In this study, we compared semen quality in men assigned to two defined groups: men from couples with unexplained infertility – idiopathic infertility (A) and young men with no experiences of infertility (B). All samples were examined by standard ejaculate analysis and sperm chromatin structure assay (SCSA). Sperm chromatin damage was significantly higher in men from group A than in those from group B. Similar results were obtained by comparison of men from group A (all men were normozoospermic) with normozoospermic men from group B. According to these results, we can suppose that chromatin disorders may be the causal factor of subfertility or infertility in some of these men. No evidence for a strong association between chromatin disorders and standard parameters of ejaculates was found. We failed to confirm a relationship between smoking and sperm quality in men from any of the investigated groups. SCSA is a method that facilitates the identification of infertile men who otherwise show normal semen variables. 相似文献
102.
103.
目的 观察脂肪抽吸对中心型肥胖患者代谢指标的影响。方法 筛选中心型肥胖患者30例,采用肿胀麻醉法,脂肪抽吸量在2000~2500ml;分别检测脂肪抽吸前2d和脂肪抽吸后1周、1个月、2个月、3个月的血脂、血清胰岛素、瘦素、脂联素、抵抗素,并换算出胰岛素抵抗指数(HO-MA-IR)、胰岛素敏感指数(ISI)和血糖及胰岛素下面积。结果脂肪抽吸后1个月、2个月血糖下面积及HOMA-IR均有不同程度的降低,ISI则有所升高(术后1周:P〈0.05;术后1月:P〈0.01);脂肪抽吸后血清瘦素较脂肪抽吸前显著降低(P〈0.01),抵抗素和脂联素较脂肪抽吸前亦有所变化,特别是在术后1个月时变化较为明显(P〈0.05),除血清瘦素、血糖下面积外,其余指标脂肪抽吸后3个月基本恢复原有水平。结论 脂肪抽吸对代谢指标在3个月内有一定的影响,特别是对糖代谢改善显著,但3个月后这种变化基本恢复到原有水平。 相似文献
104.
幕上星形细胞肿瘤Ki-67抗原表达及其预后作用 总被引:3,自引:2,他引:1
目的 探讨Ki-67抗原在幕上星形细胞肿瘤中的表达及其预后作用。方法 使用S-P免疫组化方法检测82例原发性幕上星形细胞肿瘤标本中Ki-67抗原的表达。单因素使用Kaplan-Meier法,多因素分析使用COX比例风险模型进行预后分析。结果Ki-67 指数在组织学分级GradeⅡ、Ⅲ、Ⅳ中分别为2.86%±1.57%,6.72%±3.95%,8.16%±3.92%(P<0.01)。单因素及多因素分析均提示Ki-67指数是独立的预后因素。在GradeⅡ中,Ki-67指数>2.5%与Grade Ⅲ中Ki-67指数≤2.5%的患者生存期差异无显著性(P>0.05);在GradeⅣ中,Ki-67指数≤2.5%与>2.5%的患者生存期有显著性差异(P<0.01)。结论 Ki-67指数随着各病理级别增高而增高;Ki-67指数>2.5%提示预后较差。在同一病理级别中,Ki-67指数不同,其预后有显著性差异。而部分不同病理级别的患者,随着Ki-67指数的不同,其生存期却无显著差异。联合组织病理检查及Ki-67指数检测有助于更精确地判断预后。 相似文献
105.
Rebecca Voltan Arianna Castaldello Egidio Brocca-Cofano Rita De Michele Chiara Triulzi Giuseppe Altavilla Luisa Tondelli Michele Laus Katia Sparnacci Eva Reali Riccardo Gavioli Barbara Ensoli Antonella Caputo 《Vaccine》2009
Cationic block copolymers spontaneously assemble via electrostatic interactions with DNA molecules in aqueous solution giving rise to micellar structures that protect the DNA from enzymatic degradation both in vitro and in vivo. In addition, we have previously shown that they are safe, not immunogenic and greatly increased antigen-specific CTL responses following six intramuscular inoculations of a very low dose (1 μg) of the vaccine DNA as compared to naked DNA. Nevertheless, they failed to elicit detectable humoral responses against the antigen. To gain further insight in the potential application of this technology, here we show that a shorter immunization protocol based on two DNA intramuscular inoculations of 1 μg of DNA delivered by these copolymers and a protein boost elicits in mice broad (both humoral and cellular) and long-lasting responses and increases the antigen-specific Th1-type T cell responses and CTLs as compared to priming with naked DNA. These results indicate that cationic block copolymers represent a promising adjuvant and delivery technology for DNA vaccination strategies aimed at combating intracellular pathogens. 相似文献
106.
PCR-RSSO基础上HLA-Ⅰ、Ⅱ基因分型的研究 总被引:4,自引:0,他引:4
目的通过对PCR-DNA技术的分析,探讨人类白细胞抗原(HLA)基因分型方法。方法采用PCR反向序列特异性寡核苷酸(polymerase chain reaction-reverse sequence specific oligonucleotide,PCR-RSSO)杂交技术,建立改良半量扩增体系全自动HLA-I、Ⅱ等位基因分型方法,进行了635份血液标本HLA-A、B、C、DR、DQ等位基因分型,其中166份DNA同时采用序列特异性引物技术(PCR-SSP)和手工全量扩增体系PCR-RSSO技术。对全自动半量PCR-RSSO、PCR-SSP、手工PCR-RSSO 3种方法做两两比较。结果全自动半量PCR-RSSO的分型成功率为98.4%(3 124/3 175),PCR-SSP为98.8%(656/664),手工PCR-RSSO为88.3%(733/830)。经χ2检验,全自动半量PCR-RSSO与PCR-SSP的分型成功率无统计学差异,与手工PCR-RSSO有显著差异(P<0.05)。结论PCR-RSSO可识别HLA-Ⅰ,Ⅱ共706个等位基因,覆盖WHO命名委员会2000年公布的936个等位基因的75.43%;对706个HLA等位基因的分型均为中~高分辨率,有分辨纯合子等位基因的能力;易长期保存书面的实验原始资料,即杂交条;具有成本低、劳动强度低、省时和DNA消耗量少等优点。PCR-RSSO适合于造血干细胞移植和建立造血干细胞及脐带血干细胞库的组织配型。 相似文献
107.
R. J. Bosma A. J. Kwakernaak J. J. Homan van der Heide P. E. de Jong G. J. Navis 《American journal of transplantation》2007,7(3):645-652
Obesity is a risk factor for renal graft loss. Higher body mass index (BMI) in native kidneys is associated with glomerular hyperfiltration. Whether higher BMI in renal transplants is associated with hyperfiltration is unknown. We investigated the impact of BMI on renal hemodynamics 1 year post-transplant. We analyzed glomerular filtration rate (GFR, (125)I-iothalamate) and effective renal plasma flow (ERPF, (131)I-hippurate) in 838 kidney transplants. Data were analyzed for all patients and for the subpopulation without diabetes. Long-term impact of BMI and renal hemodynamics were explored by Cox-regression. With higher BMI GFR and filtration fraction (FF) increased significantly. Multivariate analysis supported impact of BMI on GFR (adjusted r(2) of the model 0.275) and FF (adjusted r(2) of the model 0.158). This association was not explained by diabetes mellitus. On Cox-regression analysis, lower GFR and higher FF were independent determinants of overall graft loss and graft loss by patient mortality. Lower GFR and higher BMI were determinants of death-censored graft loss, with borderline contribution of higher FF. In renal transplants higher BMI is independently associated with higher GFR and FF one year posttransplant, suggesting glomerular hyperfiltration with altered afferent-efferent balance. Mechanisms underlying the long-term prognostic impact of hyperfiltration deserve further exploration. 相似文献
108.
Eun Young Jung Hyung Joo Suh Wan Soo Hong Dong Geon Kim Yang Hee Hong In Sun Hong Un Jae Chang 《Nutrition Research》2009,29(7):457-461
Cooking processes that gelatinize granules or disrupt structure might increase the glucose and insulin responses because a disruption of the structure of starch by gelatinization increases its availability for digestion and absorption in the small intestine. We hypothesized that the uncooked form of rice, which has a relatively low degree of gelatinization even though in powder form, would result in lower metabolic glucose and insulin responses compared with cooked rice (CR). To assess the effects of the gelatinization of rice on metabolic response of glucose and insulin, we investigated the glucose and insulin responses to 3 rice meals of different gelatinization degree in female college students (n = 12): CR (76.9% gelatinized), uncooked rice powder (UP; 3.5% gelatinized), and uncooked freeze-dried rice powder (UFP; 5.4% gelatinized). Uncooked rice powders (UP and UFP) induced lower glucose and insulin responses compared with CR. The relatively low gelatinization degree of UPs resulted in low metabolic responses in terms of the glycemic index (CR: 72.4% vs UP: 49.7%, UFP: 59.8%) and insulin index (CR: 94.8% vs UP: 74.4%, UFP: 68.0%). In summary, UPs that were less gelatinized than CR induced low postprandial glucose and insulin responses. 相似文献
109.
Studies have demonstrated that lipid rafts ultimately regulate the endocytosis of anthrax toxin via clathrin dependent pathway. Interestingly, GPI-anchored protein rich rafts have also been shown to be transported down to the endocytic pathway to reducing late endosomes. Taking advantage of this parallelism, we tried translating the anthrax toxin natural intoxication mechanism by administering a DNA chimera that encoded protective antigen attached to a mammalian GPI-anchor sequence at its C-terminus (pGPI-PA63). We also designed a chimera that had an additional N-terminal TPA leader sequence (pTPA.GPI-PA63) with an aim to target GPI-PA63 to ER where new CD1 molecules are synthesized. Analysis of antibody titers demonstrated successful priming and potential IgG titers after the first boost. In vitro cell proliferation studies in the presence of GPI-attached PA63 peptides revealed that there was a clonal expansion of CD4+ NK1.1+ helper T cell population which rapidly produced IL-4 in response to T cell receptor ligation. These cells provided direct B cell help that aided IgG formation. Effector responses generated by NKT cells were found to be MHC II-independent and CD1d-restricted. In addition, the group pTPA.GPI-PA63 also displayed low magnitude MHC-II restricted (CD1d-independent) NKT cell and CD4+ T cell helper responses in response to non-GPI attached PA63 peptides which overall resulted in the heightened responses seen for this group. Importantly, DNA vaccination mediated the generation of high avidity neutralizing antibodies that mediated protection against lethal toxin challenge. 相似文献
110.
当归对衰老小鼠脑组织细胞凋亡及胸腺指数的影响 总被引:2,自引:0,他引:2
目的:研究当归的抗衰老作用及作用机制。方法:用D—半乳糖诱导小鼠制成衰老模型,同时给予不同剂量的当归水煎剂,观察当归对脑组织细胞凋亡及胸腺指数的影响。结果:当归能明显抑制小鼠脑组织细胞凋亡,提高胸腺指数。结论:当归具有抗衰老作用。 相似文献