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61.
Malignancy may adversely influence the quality and behaviour of oocytes   总被引:1,自引:1,他引:1  
A case series of eight cycles of in-vitro fertilization (IVF) in five women diagnosed with malignant disorders is presented. These patients chose to defer definitive treatment for a chance for preservation of potential fertility. The response of these patients to ovarian stimulation, and the outcome, was compared with 17 IVF cycles in 12 age- matched patients with isolated tubal infertility. An apparent adverse influence of malignant disease on the quality and behaviour of oocytes was observed. Despite a comparable total number of oocytes per cycle in the two groups, a significantly reduced percentage of mature oocytes was retrieved per cycle from patients with malignant diseases. The oocytes from patients with malignant disorders were of a poorer quality and exhibited a significantly impaired fertilization rate compared to the controls. We propose that neoplastic processes, irrespective of the site or cell of origin, may have a detrimental impact on the biology of oocytes, an effect akin to that seen on spermatozoa in men with certain malignancies.   相似文献   
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63.
Erythropoietin (Epo), the hormone that is the principal regulator of red blood cell production, interacts with high-affinity receptors on the surface of erythroid progenitor cells and maintains their survival. Epo has been shown to promote cell viability by repressing apoptosis; however, the molecular mechanism involved is unclear. In the present studies we have examined whether Epo acts as a survival factor through the regulation of the bcl-2 family of apoptosis-regulatory genes. We addressed this issue in HCD-57, a murine erythroid progenitor cell line that requires Epo for proliferation and survival. When HCD-57 cells were cultured in the absence of Epo, Bcl-2 and Bcl-XL but not Bax were downregulated, and the cells underwent apoptotic cell death. HCD-57 cells infected with a retroviral vector encoding human Bcl-XL or Bcl-2 rapidly stopped proliferating but remained viable in the absence of Epo. Furthermore, endogenous levels of bcl-2 and bcl-XL were downregulated after Epo withdrawal in HCD-57 cells that remained viable through ectopic expression of human Bcl-XL, further indicating that Epo specifically maintains the expression of bcl-2 and bcl-XL. We also show that HCD-57 rescued from apoptosis by ectopic expression of Bcl-XL can undergo erythroid differentiation in the absence of Epo, demonstrating that a survival signal but not Epo itself is necessary for erythroid differentiation of HCD-57 progenitor cells. Thus, we propose a model whereby Epo functions as a survival factor by repressing apoptosis through Bcl-XL and Bcl-2 during proliferation and differentiation of erythroid progenitors.  相似文献   
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65.
AMP-18,一种新发现的胃黏膜保护因子   总被引:3,自引:0,他引:3  
AMP-18是一种新发现的由胃腺体上皮细胞合成的小分子蛋白质,独特表达于胃黏膜,机体其他部位少见,胃癌组织中表达缺失.AMP-18 由185个氨基酸组成,除去N端信号肽(20个氨基酸)后大小约18 ku,第54-150个氨基酸组成高度保守的结构域(BRICHOS区域)承担主要的生理功能.AMP-18由胃腺体上皮细胞以胞吐的方式分泌到胃黏液中,他的合成和分泌与个体生长发育有关,并受福斯高林、吲哚美辛、地塞米松等药物的影响.目前发现 AMP-18的生理功能主要有促进胃黏膜上皮细胞的有丝分裂,促进细胞的迁徙,促胃肠黏膜损伤的修复,保持胃肠黏膜的完整等.  相似文献   
66.
CD40, a member of the tumor necrosis factor-alpha receptor family, is constitutively expressed by cells of hematopoietic and non- hematopoietic origin, including fibroblasts. Signaling through this receptor molecule regulates inflammatory cytokine secretion by many cell types. Based on the recently described cytokine secretory heterogeneity of fibroblast cell subsets, we hypothesized that secretion of inflammatory cytokines by gingival fibroblast cultures may be dictated by the existence of differential proportions of cytokine- secreting subpopulations which express high levels of CD40. After examining a large number of gingival fibroblast (GF) cultures we find that the frequency of IL-6- and IL-8-secreting cells mirrors the frequency of cells expressing high levels of CD40 in these cultures. In addition, we demonstrate a direct functional relationship between CD40 expression and IL-6 or IL-8 secretion by showing that ligation of this molecule on GF, and CD40+ fibroblast subsets in particular, up- regulates secretion of these cytokines in vitro.   相似文献   
67.
68.
Objective  To evaluate the repair techniques of continuous and interrupted methods for episiotomy or perineal tears.
Design  A randomised controlled trial.
Setting  The Hospital Universitario Principe de Asturias, a state hospital belonging to the community of Madrid.
Sample  Four hundred forty-five women who had undergone vaginal deliveries with episiotomies or second-grade tearing of the perineum between September 2005 and July 2007.
Methods  One group was repaired with continuous, nonlocking sutures involving the vagina, perineum, and subcutaneous tissues. The other group had continuous, locking sutures of the vagina, interrupted sutures in the perineal muscles, and interrupted transcutaneous sutures. The threads used for stitching were identical in both groups.
Main outcome measures  The participants were questioned regarding the sensation of pain and the use of painkillers on the second and the tenth days, and 3 months postpartum.
Results  When comparing the group with continuous suture to the group with interrupted sutures, the differences included less repair time (1 minute; P = 0.017) and less suture material used (relative risk [RR], 3.2, 95% CI: 2.6–4.0). The comparison of pain on the second and tenth days, and 3 months postpartum were not statistically different between the two techniques (RR, 1.08, 95% CI: 0.74–1.57; RR, 0.96, 95% CI: 0.59–1.55; and RR, 0.68, 95% CI: 0.19–2.46, respectively).
Conclusions  Although we did not demonstrate that one technique was better than the other in the incidence of pain in the short or long term, we showed that episiotomy and perineal tear repairs with continuous suturing were quicker and used less suture material without an increase in complication than interrupted suturing.  相似文献   
69.
[目的]评估北京市社区妇女人乳头瘤病毒(HPV)的感染率;调查社区人群对HPV的认知情况以及对HPV疫苗接种的态度。[方法]采用横断面调查方法,对北京市展览路社区15 ̄54岁女性进行HPV认知和流行病学问卷调查,并留取了宫颈脱落细胞或会阴部标本进行HPV DNA检测。[结果]1013名女性接受了问卷调查,832例HPV DNA检测结果纳入了统计学分析。HPV总检出率为15.38%,高、低危型HPV感染率分别为13.34%和3.25%,同时感染高、低危型HPV的检出率为1.20%。1013名调查对象中有30.7%听说过HPV,其中51.78%知道HPV感染与宫颈癌有关;HPV的知晓率与年龄和教育程度有关(P〈0.05);经过简单宣教后,75.91%愿意接种HPV疫苗。[结论]北京市社区妇女HPV现患率较高,对HPV的知晓率也较高。开展公众健康教育,提高人群的认识水平是疫苗计划获得成功的关键因素。  相似文献   
70.
A prospective randomized study was performed to evaluate the use of a urinary luteinizing hormone (LH) detection kit with 1 insemination as compared with 2 alternate day inseminations with timing based on previous cycle length and basal body temperature changes. The study involved 60 patients who underwent a total of 264 therapeutic donor insemination cycles using cryopreserved semen specimens. Patients alternated LH-kit timed cycles with cycles timed by non-LH methods for a total of 6 cycles or until pregnancy was achieved. Fecundability rates were 12.3% for LH-kit cycles and 5.3% for non-LH method cycles. The difference in outcome was not statistically significant. However, when the LH kit plus 1 insemination was compared with 2 inseminations timed by conventional methods, there appeared to be a distinct monetary and time expenditure advantage. These findings suggest that sufficient advantage may be derived from use of an LH kit to recommend its use on a routine basis for the timing of therapeutic donor insemination.  相似文献   
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