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   1524篇
  免费   110篇
  国内免费   9篇
耳鼻咽喉   11篇
儿科学   22篇
妇产科学   34篇
基础医学   161篇
口腔科学   29篇
临床医学   168篇
内科学   223篇
皮肤病学   43篇
神经病学   64篇
特种医学   55篇
外科学   322篇
综合类   15篇
一般理论   1篇
预防医学   88篇
眼科学   40篇
药学   77篇
中国医学   2篇
肿瘤学   288篇
  2023年   13篇
  2022年   7篇
  2021年   12篇
  2020年   20篇
  2019年   25篇
  2018年   31篇
  2017年   30篇
  2016年   29篇
  2015年   32篇
  2014年   33篇
  2013年   45篇
  2012年   80篇
  2011年   79篇
  2010年   39篇
  2009年   47篇
  2008年   69篇
  2007年   89篇
  2006年   65篇
  2005年   81篇
  2004年   46篇
  2003年   64篇
  2002年   62篇
  2001年   46篇
  2000年   62篇
  1999年   62篇
  1998年   17篇
  1997年   20篇
  1996年   18篇
  1995年   10篇
  1994年   8篇
  1993年   13篇
  1992年   40篇
  1991年   34篇
  1990年   44篇
  1989年   27篇
  1988年   16篇
  1987年   32篇
  1986年   20篇
  1985年   20篇
  1984年   13篇
  1983年   12篇
  1982年   8篇
  1981年   7篇
  1979年   10篇
  1975年   5篇
  1974年   10篇
  1973年   7篇
  1972年   7篇
  1970年   5篇
  1966年   10篇
排序方式: 共有1643条查询结果,搜索用时 15 毫秒
71.
Peritoneal fluid (PF) from 10 infertile patients with endometriosis, obtained during the follicular phase of the cycle during laparoscopy, did not promote two-cell mouse embryo growth to the extent observed by fluid obtained from seven normal controls. Five molecular weight (MW) fractions were obtained by ultrafiltration, and each was used as media supplement in the assay and compared with PF fractions from normal controls. All fractions of PF from patients with endometriosis inhibited mouse embryo growth to a greater extent than did normal controls. However, the MW fractions greater than 100,000 daltons showed greater inhibition of embryo development than did fractions less than 100,000 daltons. This study of cell-free PF suggests the presence of a humoral factor greater than 100,000 daltons that is inhibitory on mouse embryo growth.  相似文献   
72.
In patients with clinical stage I non-seminomatous testicular cancer only limited information is available about the administrative problems with the surveillance programme, in particular if this policy is to be implemented in a geographically extended country with limited computerised tomography (CT) resources. One hundred and two patients with non-seminomatous testicular cancer clinical stage I and low-risk histology (MRC criteria, UK) were followed by the surveillance policy for at least 1 year after orchiectomy (median 47 months, range 21-81 months). Twenty-two patients (22%) relapsed after a median time of 5 months (range 2-18 months), 14 of them in the retroperitoneal space. Serum alpha-fetoprotein and/or human chorionic gonadotrophin were elevated in eight of the 22 relapsing patients. The progression-free and cancer-corrected survival rates were 78% and 99% respectively. Patient non-compliance did not represent a major problem, whereas the regular and adequate performance of necessary CT examinations yielded some administrative difficulties. One and 3 years after orchiectomy about 50% of the relapse-free patients had no psychological problems and were satisfied with the surveillance programme, whereas 46% reported minor and 4% major psychological distress. Despite non-negligible administrative difficulties in geographically extended countries, surveillance is feasible and safe in compliant patients with low-risk non-seminomatous testicular cancer stage I. The responsible cancer centre and the local hospitals should establish a high degree of cooperation and enable adequate follow-up examinations in these patients.  相似文献   
73.
Blood samples were obtained during early follicular, periovulatory, and luteal phases in four women with out-of-phase endometrial biopsy specimens and four normal controls. In the study cycle, follicular development was evaluated and a late luteal phase endometrial biopsy was performed in each subject. Area under the luteal phase progesterone curve positively correlated with degree of maturity of the endometrial biopsy. Peak serum estradiol, maximum follicular diameter, and both immunoactivity and bioactivity of the preovulatory luteinizing hormone and follicle-stimulating hormone surges were similar in the luteal phase defect cycles as compared with normal cycles. Likewise luteinizing hormone bioactivity in the luteal phase of the luteal phase defect cycles was similar to that of normals. These data show that the immunoactivity and bioactivity of periovulatory and luteal phase gonadotropins may be normal in luteal phase defect cycles.  相似文献   
74.
OBJECTIVE: To determine the possible role of the immune system in the pathogenesis of endometriosis. DESIGN: The lymphocyte proliferative response in the presence of autologous endometrial cells was assayed by tritiated thymidine incorporation. SETTING: Patients were recruited from a university outpatient clinic. MAIN OUTCOME MEASURE: To determine the lymphocyte proliferative response to endometrium in controls and patients with endometriosis. PARTICIPANTS: Twenty patients with endometriosis and 26 control women were studied. RESULTS: The lymphocyte proliferative response in the presence of autologous endometrium was significantly lower in women with endometriosis when compared with controls. CONCLUSION: This study indicates that an altered lymphocyte/endometrial cell relationship is operational in women with endometriosis and may contribute to the pathogenesis of the disease.  相似文献   
75.
Background: We concluded a program in which we administeredradiotherapy only to clinical stages I and II Hodgkin's diseasepatients at standard risk, with the addition of 4 cycles ofcombination chemotherapy before radiotherapy for high-risk patients. Patients and methods: From 1980 to 1991, 313 patients with clinicalstages I or II Hodgkin's disease underwent treatment in ourhospital. Fifty percent of the patients in groups previouslyidentified as being at high risk for relapse received 4 cyclesof combination chemotherapy before radiotherapy. The remaininghalf of the patients received radiotherapy only. Results: Low- and high-risk patients aged 15–59 yearshad, respectively, complete remission (CR) rates of 97% and94%, 5-year survivals of 95% and 91%, and 5-year freedom fromrelapse (FFR) rates of 78% and 89%. Older low- and high-riskgroups had CR rates of 97% and 93%, 5-year survivals of 60%and 56% and 5-year FFR of 77% and 93%, respectively. Conclusion: Here we present our favorable results after treatingstandard-risk patients with clinical stages I and II Hodgkin'sdisease with radiotherapy only. With the addition of chemotherapy,the rate of relapse in the high-risk patients was reduced belowthat of the standard-risk patients. Overall survival was thesame for the high- and standard-risk patients. adjuvant chemotherapy, Hodgkin's disease, radiotherapy, stages I and II  相似文献   
76.
Jacobsen KD  Fosså SD  Bjøro TP  Aass N  Heilo A  Stenwig AE 《European urology》2002,42(3):229-38; discussion 237-8
OBJECTIVE: To evaluate gonadal function and fertility in patients with bilateral testicular cancer (TC). METHODS: In 1999, 63 patients with bilateral invasive TC or carcinoma in situ (CIS) in the contralateral testis completed a mailed questionnaire evaluating their fatherhood (Cases). Their gonadal function had also been assessed after the first orchiectomy for TC before further treatment.The results were compared with those from 174 patients with unilateral TC (Controls). RESULTS: In Cases the post-orchiectomy serum levels of FSH and LH were above those of the Controls (p<0.001). Serum testosterone was similar, whereas sperm concentrations were lower in Cases (p<0.001). In Cases with metachronous invasive TC the level of serum FSH was associated with the interval between the two diagnoses. After the first orchiectomy, 10 of 25 Cases (40%) initiated a pregnancy, in 4 Cases by assisted fertilization. In the Control group 74% of the patients who attempted fatherhood succeeded (p=0.002). CONCLUSIONS: After unilateral orchiectomy for TC elevated serum FSH and/or oligospermia represent a high-risk factor of metachronous bilateral TC or synchronous CIS. At least one-third of these patients attempting fatherhood are successful after the first orchiectomy. Assisted fertilization is often necessary and the overall paternity rate is below that of patients with unilateral TC.  相似文献   
77.
BACKGROUND: The majority of hemochromatosis patients are homozygous for the HFE-C282Y mutation. However, less than half of C282Y homozygous subjects identified by population screening studies actually develop the disease. The cytokine TNF-alpha is implicated in the regulation of iron metabolism at different levels. Our aim was to study the role of TNF-alpha and its promoter polymorphisms in the phenotypic expression of hemochromatosis in individuals with and without the C282Y mutation. METHODS: We studied 4 groups of 10 subjects each: (1) C282Y homozygotes without clinical hemochromatosis; (2) C282Y homozygotes with hemochromatosis; (3) secondary hemochromatosis (without C282Y mutation); and (4) controls. Groups were age-matched and sex-matched. Peripheral blood mononuclear cells (PBMC) were stimulated with lipopolysaccharide (LPS) and the release of TNF-alpha was measured. Additionally, the G/A polymorphisms at position -238 and -308 of the TNF-alpha, gene were determined by PCR and RFLP analysis in 178 hemochromatosis patients and 41 controls. RESULTS: TNF-alpha production from PBMC at 8 and 24 h after increasing concentrations of LPS stimulation were similar in the four groups. The prevalence of TNF-alpha polymorphisms was similar in patients and controls. The prevalences of cirrhosis, siderosis, median s-ferritin and median ALT values were similar in patients with and without the TNF-alpha polymorphisms. CONCLUSIONS: Neither TNF-alpha, released from PBMC nor the presence of TNF-alpha polymorphisms seem to be associated with disease manifestation in hemochromatosis.  相似文献   
78.
A 2-day-old girl was admitted to surgery for repair of a left-sided diaphragmatic hernia (CDH). Preoperatively, an umbilical vein catheter (UVC) was inserted with the tip in the left hypochondrium. The UVC tip position was unchanged radiographically peroperatively. At the fifth postopertive day abdominal distension and signs of gastric outlet obstruction appeared. Explorative laparotomy found liver necrosis at the site of the catheter tip and parenteral nutrition ascites. J Pediatr Surg 37:E21.  相似文献   
79.
Predictors of 'patient satisfaction' with hospitalization at a specialized cancer hospital in Norway are examined in this study. Two weeks after their last hospitalization, 2021 consecutive cancer patients were invited to rate their satisfaction with hospitalization, quality of life, anxiety and depression. Compliance rate was 72% (n = 1453). Cut-off levels separating dissatisfied from satisfied patients were defined. It was found that 92% of the patients were satisfied with their stay in hospital, independent of cancer type and number of previous admissions. Performance of nurses and physicians, level of information perceived, outcome of health status, reception at the hospital and anxiety independently predicted 'patient satisfaction'. The model explained 35% of the variance with an area under the curve of 0.76 of the Receiver Operator Curve. Cancer patients' satisfaction with their hospital stay was high, and predicted by four independently predictive variables related to the performance of caregivers. These suggest areas for further improvement in the healthcare service.  相似文献   
80.
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