首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   295篇
  免费   3篇
妇产科学   210篇
基础医学   50篇
临床医学   2篇
内科学   22篇
外科学   8篇
综合类   3篇
眼科学   1篇
肿瘤学   2篇
  2021年   15篇
  2019年   5篇
  2018年   6篇
  2017年   6篇
  2016年   3篇
  2015年   2篇
  2014年   8篇
  2013年   1篇
  2012年   6篇
  2011年   5篇
  2010年   7篇
  2009年   5篇
  2008年   5篇
  2007年   4篇
  2006年   7篇
  2005年   10篇
  2004年   16篇
  2003年   17篇
  2002年   7篇
  2001年   18篇
  2000年   11篇
  1999年   18篇
  1998年   9篇
  1997年   5篇
  1996年   5篇
  1995年   6篇
  1994年   4篇
  1993年   3篇
  1992年   10篇
  1991年   8篇
  1990年   2篇
  1989年   11篇
  1988年   21篇
  1987年   6篇
  1986年   8篇
  1985年   6篇
  1984年   5篇
  1982年   1篇
  1979年   5篇
  1977年   1篇
排序方式: 共有298条查询结果,搜索用时 31 毫秒
31.
Hormonal manipulation of endometrial maturation   总被引:6,自引:0,他引:6  
Three experimental protocols were devised to induce endometrial maturation in 12 women with ovarian failure. Each was planned to serve a dual purpose: to resolve a particular clinical situation related to synchronization between ovum donor and recipient and to answer a specific question about endometrial physiology. A fourth protocol of sequential estrace (2-6 mg/day) and progesterone (P4; 25-50 mg/day, im) simulating the 28-day natural cycle, served as a control protocol (18 cycles). A short follicular phase protocol consisted of only 6 days of estrogen (E) administration before addition of P4 (13 cycles). In the long follicular phase protocol (5 cycles), estrace was given for 3-5 weeks, and P4 administration was accordingly postponed. In 6 accelerated secretory transformation cycles, 150 mg/day P4 were administered, im, from day 15 onward. The adequacy of the induced endometrial cycles was evaluated by hormonal, morphological, and histochemical criteria relevant to endometrial normalcy and receptivity. Serum estradiol levels and the areas under the estradiol curves for the long and short follicular phase protocols differed significantly from those during the control cycles (P less than 0.005). Areas under the estradiol curves in the accelerated secretory transformation protocol yielded significantly higher P4 values than those in all other protocols (P less than 0.05). All biopsies in the 3 experimental protocols compared favorably with those of the control protocol. Glycocalyx intensity (periodic acid-Schiff) and the amount of galactose residues in the glycocalyx (Ricinus communis-I agglutinin) were greatest during the periimplantation interval. We conclude that a very short exposure of the human endometrium to E or, conversely, prolonged E stimulation will allow normal endometrial maturation with the addition of P4. Supraphysiological doses of P4 in the accelerated secretory transformation protocol significantly enhanced endometrial maturational processes.  相似文献   
32.
We profiled microRNAs (miRNAs) in cell-free serum and plasma samples from human volunteers using deep sequencing of barcoded small RNA cDNA libraries. By introducing calibrator synthetic oligonucleotides during library preparation, we were able to calculate the total as well as specific concentrations of circulating miRNA. Studying trios of samples from newborn babies and their parents we detected placental-specific miRNA in both maternal and newborn circulations and quantitated the relative contribution of placental miRNAs to the circulating pool of miRNAs. Furthermore, sequence variation in the placental miRNA profiles could be traced to the specific placenta of origin. These deep sequencing profiles, which may serve as a model for tumor or disease detection, allow us to define the repertoire of miRNA abundance in the circulation and potential uses as biomarkers.  相似文献   
33.
Twenty-one patients with septate uteri and 2 patients with a T-shaped uterine anomaly and recurrent abortions underwent wedge metroplasty during the period from September 1978 to August 1983. Thirteen patients had a characteristic history of one or more abortions associated with the septate uterus and absence of other metabolic and endocrine abnormalities. Ten other patients, including the two with a T-shaped uterine anomaly, either had one or more abortions of an uncharacteristic nature with absence of other abnormalities or had one or more characteristic abortions in addition to the presence of other metabolic, endocrine, or surgically correctable disease. The application of wedge metroplasty for the surgical reconstruction of the uterus yielded equally gratifying results in both groups with approximately two thirds of the patients having a term delivery or carrying a pregnancy in the third trimester.  相似文献   
34.
The purpose of this study was to investigate any influence of maternal and/or paternal age on gamete characteristics and pregnancy outcomes in intracytoplasmic sperm injection (ICSI) cycles. In all, 821 consecutive ICSI cases were analysed retrospectively. While a significant linear decline in semen volume was detected, no significant differences in the concentration, motility or morphology of the spermatozoa were found with paternal ageing. A significant decline in the number of oocytes retrieved and the number of mature oocytes obtained was found with advancing maternal age. An increase in the occurrence of digyny was noted with parental ageing, while no difference in single or bipronuclear fertilization was found. Older women had a decreased incidence of single pronucleus formation and an increase in digyny, but no significant difference in the percentage of oocytes that underwent two-pronuclear fertilization was detected with regard to maternal ageing. Pregnancy outcomes were not influenced by the age of the male partner, while a strong negative correlation was found with maternal ageing. To better analyse male partner ageing as a factor affecting pregnancy outcome, we analysed a subgroup of patients with a female partner aged <35 years who underwent ICSI. No paternal influence on ICSI pregnancy outcome was found in this subgroup of patients. We conclude that the influence on pregnancy outcome after ICSI is related mostly to maternal and not paternal age.   相似文献   
35.
To determine the fertility potential of patients with apparent ovarian failure, a retrospective analysis of 86 ovarian failure patients in the Norfolk oocyte donation program was performed. None of the 23 patients with primary ovarian failure ovulated. Seven of 63 (11.1%) with secondary ovarian failure did ovulate, and three of 63 (4.8%) conceived and delivered normal, healthy infants. Of patients whose etiology for ovarian failure was partial ovarian resection or chemotherapy, the ovulation rate and pregnancy rate were 30.8 and 15.4%, respectively, compared with 5.0 and 1.7%, respectively, for the other patients with secondary ovarian failure. Serum estradiol and FSH obtained during hormone replacement were not predictive of the resumption of normal reproductive functions. Therefore, it is recommended that patients with secondary ovarian failure, especially in the better-prognosis group, be treated with a trial of estradiol replacement and have close monitoring for ovulation before oocyte donation.  相似文献   
36.
Purpose The prevalence of Ureaplasma urealyticumand Mycoplasma hominisin the endocervix at the time of oocyte collection in women undergoing in vitrofertilization (IVF) was examined using the polymerase chain reaction (PCR).Methods All women were treated with tetracycline following sample collection.Results U. urealyticumwas identified in 56 (17.2%) of 326 women while M. hominiswas present in only 5 (2.1%) of 235 women. U. urealyticumwas detected at a higher frequency (P =0.01) in those women whose IVF cycle failed prior to embryo transfer. This organism was present in 8 of 19 (42.1%) women with either no fertilization or no embryo transfer, 19 of 148 (12.8%) who had no evidence of pregnancy following embryo transfer, 6 of 30 (20,0%) who had only a transient (biochemical) pregnancy, 5 of 14 (35.7%) with a spontaneous abortion, and 18 of 115 (15.6%) with a term birth. Of the eight women with U. urealyticumwho had no embryos transferred, male factor was the cause of infertility in five cases, two women had tubal occlusions while in one woman the diagnosis was idiopathic. Therefore, poor sperm quality, and not a U. urealyticuminfection, might explain the failure of most of these cases to proceed to the stage of embryo transfer. Analysis of all patients revealed no association between male factor infertility and U. urealyticumin the cervix.Conclusions U. urealyticum,but not M. hominis,is present in the cervices of many culture-negative women. Its presence, however, does not influence IVF outcome subsequent to embryo transfer in women treated with tetracycline after oocyte retrieval.Presented at the IXth World Congress on In Vitro Fertilization and Alternate Assisted Reproduction, April 3–7, 1995, Vienna, Austria.  相似文献   
37.
38.
The role of in vitro fertilization in infertile patients with endometriosis   总被引:2,自引:1,他引:1  
Thirty-nine cycles were studied in patients with a history of endometriosis who went through in vitro fertilization. In 15 cycles, there was no evidence of endometriosis; in 10 cycles, the patients had mild or moderate disease; in 14 cycles, severe or extensive endometriosis was found. The pregnancy rates per cycle were 33%, 60%, and 7%, respectively (groups I and II, no significant difference; groups II and III, P less than 0.01). The difference was due to the different number of oocytes aspirated at laparoscopy because of technical problems in the cases with severe and extensive disease. There was also a significant difference in the number of pregnancies per transferred cycles. There was no difference in the luteal phase in the three groups. The reproductive potential, which seemed to be similar in groups I and II, was severely impaired in the group with severe endometriosis.  相似文献   
39.
The purpose of this study was to evaluate the ovarian response and in vitro fertilization/embryo transfer (IVF-ET) results in patients with tubal infertility and two ovaries, according to (1) the degree and extent of pelvic disease (isolated tubal or tubo-ovarian) and (2) previous adnexal surgical procedures. A total of 549 patients who underwent 1031 IVF-ET cycles were evaluated. Significant findings were as follows: (1) No differences were found in the number of preovulatory oocytes, fertilization rates, or serum estradiol levels in the follicular phase between any classes of tubo-ovarian disease. (2) Patients with a "frozen pelvis" had significantly fewer follicles aspirated than those in any other category, although they had equivalent numbers of preovulatory oocytes retrieved and pregnancy rates. (3) Patients with previous bilateral tubal ligation had higher pregnancy rates than patients with severe tubo-ovarian disease. (4) The type of prior pelvic surgical procedure had no effect on IVF-ET outcome. Although patients with no cause of infertility other than tubal ligation had better results, these patients had previously proven fertility. We conclude that neither the stage of tubo-ovarian disease nor any history of pelvic adhesions or tubal surgery has a significant impact on the efficiency of IVF-ET.  相似文献   
40.
OBJECTIVE: To analyze IVF outcomes in patients with a history of one or more elevations in basal FSH who have a normal basal FSH at the start of their IVF cycle, compared with the general IVF population. DESIGN: Retrospective clinical study. SETTING: University hospital. PATIENT(S): General IVF patient population. INTERVENTION(S): Patients received standard IVF gonadotropin protocols, oocyte retrieval, and embryo transfer. MAIN OUTCOME MEASURE(S): Oocyte yield, fertilization, implantation, clinical pregnancy, and cancellation rate. RESULT(S): Oocyte yields were lower in patients with a history of elevated basal FSH, for all age groups, and showed an age-dependent decline in all patients. Over the age of 40 years, both implantation and clinical pregnancy rates were lower in these patients, with no significant difference observed in patients under the age of 40 years. No pregnancies were observed in patients with a history of three or more elevated FSH levels, regardless of age. CONCLUSION(S): A history of elevated basal FSH levels in patients under the age of 40 years predicts a lower oocyte yield in IVF cycles with normal basal FSH levels but does not translate to either lower pregnancy or implantation rates. Patients aged >40 years with prior elevations in basal FSH levels have both compromised ovarian response and compromised embryo quality relative to those with normal FSH levels, as illustrated by lower oocyte yield, higher cancellation rates, and lower implantation and pregnancy rates.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号