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   837篇
  免费   64篇
  国内免费   13篇
耳鼻咽喉   7篇
儿科学   36篇
妇产科学   65篇
基础医学   163篇
口腔科学   15篇
临床医学   66篇
内科学   118篇
皮肤病学   17篇
神经病学   49篇
特种医学   147篇
外科学   41篇
综合类   61篇
预防医学   51篇
眼科学   4篇
药学   42篇
中国医学   3篇
肿瘤学   29篇
  2022年   4篇
  2021年   8篇
  2020年   7篇
  2019年   6篇
  2018年   17篇
  2017年   3篇
  2016年   10篇
  2015年   12篇
  2014年   12篇
  2013年   36篇
  2012年   17篇
  2011年   25篇
  2010年   16篇
  2009年   35篇
  2008年   31篇
  2007年   29篇
  2006年   24篇
  2005年   25篇
  2004年   24篇
  2003年   30篇
  2002年   25篇
  2001年   20篇
  2000年   19篇
  1999年   22篇
  1998年   47篇
  1997年   42篇
  1996年   26篇
  1995年   18篇
  1994年   26篇
  1993年   22篇
  1992年   23篇
  1991年   24篇
  1990年   19篇
  1989年   21篇
  1988年   16篇
  1987年   18篇
  1986年   17篇
  1985年   24篇
  1984年   13篇
  1983年   8篇
  1982年   15篇
  1981年   10篇
  1980年   9篇
  1979年   4篇
  1978年   11篇
  1977年   8篇
  1976年   9篇
  1975年   4篇
  1970年   3篇
  1967年   4篇
排序方式: 共有914条查询结果,搜索用时 15 毫秒
1.
A cohort study was undertaken to compare the effect at the timeof oocyte retrieval of the i.v. administration of either 1000ml of lactated Ringer' solution or 1000 ml of a 5% solutionof human albumin on in-vitro fertilization patients at riskfor severe ovarian hyperstimulation syndrome (OHSS). A totalof 207 patients with an oestradiol concentration > 10 000pmol/l and/or > 15 follicles (>10 mm diameter) on theday of human chorionic gonadotrophin (HCG) injection were reviewed.Of these, 158 women received 500 ml of lactated Ringer’ssolution both before and after egg retrieval, and 49 women receivedtwo infusions of 500 ml of 5% human albumin in normal salineat the time of egg retrieval. Severe OHSS developed in two patientswho received human albumin and in 10 women who did not receivethe albumin. This difference was not statistically significant.There were no differences between the two groups in terms ofage, number of follicles punctured at transvaginal oocyte retrievalor oestradiol concentration at the time of HCG injection. Theadministration of a 5% human albumin solution does not preventthe development of severe OHSS in at risk patients. It doesappear to blunt the severity of the condition.  相似文献   
2.
3.
The treatment of antibody-mediated spermagglutination by corticosteroidtherapy has a high incidence of side-effects and sperm washingis often followed by re-agglutination. The possibility of enzymaticdisagglutination was therefore investigated. In the first partof the study the effects of four proteases on sperm motility,vitality and longevity were evaluated. Subtilisin had prohibitivelydetrimental effects even at 10 U/ml. However, chymotrypsin (500U/ml), trypsin (500 U/ml) and papain (50 U/ml) had no adverseeffects. In the second series of experiments one or more ofthese latter three enzymes was found to disagglutinate spermatozoawhich had previously been incubated with sperm-agglutinatingantibody-positive sera in 87% of cases. Although further investigationis required, enzymatic disagglutination may be beneficial forthe treatment of immunologically mediated spermagglutination.  相似文献   
4.
Hyperreactio luteinalis associated with chronic renal failure   总被引:1,自引:0,他引:1  
Hyperreactio luteinalis is a rare benign condition characterized by bilateral ovarian enlargement associated with pregnancies where high concentrations of maternal serum human chorionic gonadotrophins are present. This condition may mimic the ovarian hyperstimulation syndrome. We report a case of a 34 year old woman with a history of chronic renal failure on haemodialysis who presented at 10 weeks' gestational age with hyperreactio luteinalis which was treated conservatively. Because of chronic renal failure, the presentation and course of the disease was different from that which has been previously reported.  相似文献   
5.
BACKGROUND: Boys and young men with hemophilia treated with factor infusions before 1985 had a substantial risk of acquiring the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome. This study was designed to assess the effects of HIV and hemophilia per se on neurological function in a large cohort of subjects with hemophilia, and to investigate the relationships between neurological disease and death during follow-up. METHODS: Three hundred thirty-three boys and young men (207 HIV seropositive and 126 HIV seronegative) were evaluated longitudinally in a multicenter, multidisciplinary study. Neurological history and examination were conducted at baseline and annually for 4 years. The relationship between neurological variables, HIV serostatus, CD4+ cell counts, and vital status at the conclusion of the study was examined using logistic regression models. RESULTS: The risks of nonhemophilia-associated muscle atrophy, behavior change, and gait disturbance increased with time in immune compromised HIV-seropositive subjects compared with HIV seronegative or immunologically stable HIV-seropositive subjects. The risk of behavior change in immune compromised HIV-seropositive hemophiliacs, for example, rose to 60% by year 4 versus 10% to 17% for the other study groups. Forty-five subjects (13.5%), all of whom were HIV seropositive, died by year 4. Subjects who died had had increased risks of hyperreflexia, nonhemophilia-associated muscle atrophy, and behavior change. CONCLUSIONS: These results indicate that immune compromised, HIV-seropositive hemophiliacs have high rates of neurological abnormalities over time and that neurological abnormalities were common among subjects who later died. By contrast, immunologically stable HIV-seropositive subjects did not differ from the HIV-seronegative participants. Hemophilia per se was associated with progressive abnormalities of gait, coordination, and motor function.  相似文献   
6.
We have investigated the ploidy profile of morphologically normal mucosa adjacent to high grade CIN (   n = 16  ) and also from normal cervix ( n = 18). DNA ploidy was assessed using flow cytometry and image analysis. All cases were diploid by both modalities. Our results show that morphologically normal squamous mucosa has a stable ploidy profile even when it lies adjacent to high grade CIN. This finding supports the view that high grade CIN is a neoplastic expansion of transformed cells rather than the result of a field change effect.  相似文献   
7.
8.
Trichloroethylene (TCE) is a prevalent occupational and environmental contaminant that has been reported to cause a variety of toxic effects. Here, we have undertaken studies to test the hypothesis that TCE exposure adversely affects sperm function and fertilization. Sperm retrieved from mice exposed to TCE (1000 ppm) by inhalation for 1 to 6 weeks were incubated in vitro with eggs isolated from superovulated female mice. The number of sperm bound per egg was significantly decreased when mice were exposed to TCE for 2 and 6 weeks but not at exposures of 1 and 4 weeks. In vivo fertilization was also determined in superovulated female mice mated with males exposed to TCE for 2 to 6 weeks. The percentages of eggs fertilized, as assessed by the presence of two pronuclei, were significantly decreased after 2 and 6 weeks of TCE exposure. A slight but insignificant decrease was observed after 4 weeks of TCE exposure. The direct effects of TCE and its metabolites, chloral hydrate (CH) and trichloroethanol (TCOH), on in vitro sperm-egg binding were also investigated. Sperm-egg binding was significantly decreased when sperm were pretreated with CH (0.1-10 microg/mL). Significantly lower levels of sperm-egg binding were also detected with TCOH (0.1-10 microg/mL), although the decreases were not as pronounced as those for CH. These results showed that TCE exposure leads to impairment of sperm fertilizing ability, which may be attributed to TCE metabolites, CH, and TCOH.  相似文献   
9.
10.
OBJECTIVE: Despite the many procedures introduced to prevent surgical site infection during cardiothoracic surgery, serious infections still occur. We attempted to reduce surgical site infection by spraying antibiotic solution in the operative field--a procedure since introduced at 4 other Japanese institutions. METHODS: In the latter half of 1990, we began spraying an antibiotic solution of cefazolin (1g) and gentamicin (40 mg)/40 ml of saline placed in a 50 ml syringe and dispensed through an 18 G needle bent at 60 to 80 degrees to clean the wound during surgery. RESULT: No deep surgical site infections or deaths due to infection have occurred among the 502 patients undergoing cardiothoracic surgery under cardiopulmonary bypass at our hospital. This method was used in over 2,100 cases of similar procedures at 4 other institutions. There were 3 deaths due to severe surgical site infection (0.11%). At one institution treating over 1,000 cases a year, the incidence of death due to surgical site infection decreased significantly after this method was introduced. CONCLUSION: These preliminary experiences show that spraying antibiotic solution in the operative field reduces the risk of surgical site infection in cardiothoracic surgery.  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