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   831篇
  免费   28篇
  国内免费   3篇
耳鼻咽喉   2篇
儿科学   56篇
妇产科学   18篇
基础医学   91篇
口腔科学   23篇
临床医学   109篇
内科学   156篇
皮肤病学   9篇
神经病学   19篇
特种医学   167篇
外科学   40篇
综合类   5篇
一般理论   1篇
预防医学   30篇
眼科学   6篇
药学   94篇
肿瘤学   36篇
  2022年   6篇
  2021年   12篇
  2020年   4篇
  2018年   13篇
  2017年   5篇
  2016年   9篇
  2015年   12篇
  2014年   17篇
  2013年   31篇
  2012年   15篇
  2011年   31篇
  2010年   36篇
  2009年   27篇
  2008年   23篇
  2007年   21篇
  2006年   16篇
  2005年   22篇
  2004年   24篇
  2003年   17篇
  2002年   20篇
  2001年   17篇
  2000年   16篇
  1999年   12篇
  1998年   35篇
  1997年   29篇
  1996年   28篇
  1995年   26篇
  1994年   30篇
  1993年   20篇
  1992年   8篇
  1991年   12篇
  1990年   19篇
  1989年   21篇
  1988年   24篇
  1987年   18篇
  1986年   14篇
  1985年   21篇
  1984年   13篇
  1983年   12篇
  1982年   23篇
  1981年   15篇
  1980年   12篇
  1979年   8篇
  1978年   4篇
  1977年   9篇
  1976年   16篇
  1975年   9篇
  1968年   4篇
  1967年   3篇
  1965年   3篇
排序方式: 共有862条查询结果,搜索用时 0 毫秒
51.
Fifteen infants with life-threatening gastrointestinal anomalies received total parenteral feeding for periods ranging from 10 to 54 days; their ages ranged from one day to 5 months. The solutions were administered through peripheral veins. All patients gained weight during the period of observation and no cases of septicaemia were encountered.  相似文献   
52.
Inpatient management: a new role for interventional radiologists   总被引:2,自引:0,他引:2  
Ring  EJ; Kerlan  RK  Jr 《Radiology》1985,154(2):543
  相似文献   
53.
商陆多糖Ⅰ(PAP-I),0.3~3μg·ml-1和小鼠脾细胞培养3~5d可显著增强其杀伤P815肿瘤细胞活性及IL-2(250~500IU·ml-1)诱导的LAK细胞活性,最适浓度为1μg·ml-1。PAP-I及IL-2和脾细胞培养的上清液对P815肿瘤细胞无细胞毒作用,但能增强脾细胞及LAK细胞杀瘤活性。PAP-I,5,10及50mg·kg-1,ip可增强脾细胞杀伤P815和L929细胞的活性及IL-2诱导的LAK细胞活性。  相似文献   
54.
55.
INTRODUCTION: Benign prostatic hyperplasia (BPH) is associated with bothersome lower urinary tract symptoms (LUTS) and reduced patient quality of life (QoL). Phosphodiesterase (type) 5 (PDE5) inhibitors such as vardenafil are commonly used for the treatment of erectile dysfunction (ED), but have also been shown to improve the symptoms of BPH. This randomised, double-blind, placebo-controlled study investigated the effects of vardenafil on LUTS and QoL in men with BPH/LUTS, with or without concomitant ED. METHODS: Men aged 45-64 yr with BPH/LUTS and an International Prostate Symptom Score (IPSS) > or =12 were randomised to receive either 10mg vardenafil or placebo twice daily. LUTS were assessed with the use of two primary efficacy parameters, IPSS score and maximum urinary flow rate (Qmax), as well as postvoid residual (PVR) urine volume; ED was measured with the use of the erectile function (EF) domain score of the International Index of Erectile Function (IIEF-EF); and QoL was assessed with the Urolifetrade mark QoL-9 questionnaire. RESULTS: After 8 wk of treatment, there was a significant improvement in the IPSS total score in the vardenafil group compared with placebo (-5.9 and -3.6, respectively; p=0.0013). Nominally significant improvements in irritative and obstructive IPSS subscores (p=0.0017 and p=0.0081, respectively), EF (p=0.0001), and Urolife QoL-9 (p<0.0001) were also associated with vardenafil treatment. Qmax and PVR urine volume did not change significantly with treatment, although baseline values were already considered close to normal. Vardenafil was generally well tolerated, with most adverse events considered mild or moderate in severity. CONCLUSIONS: Vardenafil treatment significantly improved LUTS, EF, and QoL in men with BPH/LUTS. Vardenafil may be considered a promising treatment option for men with symptoms secondary to BPH.  相似文献   
56.
The goal of this phase II multicenter clinical trial was to evaluate a new intensive chemotherapy program for adults with untreated acute lymphoblastic leukemia (ALL) and to examine prospectively the impact of clinical and biologic characteristics on the outcome. One hundred ninety-seven eligible and evaluable patients (16 to 80 years of age; median, 32 years of age) received cyclophosphamide, daunorubicin, vincristine, prednisone, and L-asparaginase; 167 patients (85%) achieved a complete remission (CR), 13 (7%) had refractory disease, and 17 (9%) died during induction. A higher CR rate was observed in younger patients (94% for those < 30 years old, 85% for those 30 to 59 years old, and 39% for those > or = 60 years old, P < .001) and in those who had a mediastinal mass (100%) or blasts with a T-cell immunophenotype. Eighty percent of B-lineage and 97% of T-cell ALL patients achieved a CR (P = .01). The coexpression of myeloid antigens did not affect the response rate or duration. Seventy percent of those with cytogenetic or molecular evidence of the Philadelphia (Ph) chromosome and 84% of those without such evidence achieved a CR (P = .11). Patients in remission received multiagent consolidation treatment, central nervous system prophylaxis, late intensification, and maintenance chemotherapy for a total of 24 months. After a median follow-up time of 43 months, the median survival for all 197 patients is 36 months; the median remission duration for the 167 CR patients is 29 months. Favorable pretreatment characteristics relative to remission duration or survival are younger age, the presence of a mediastinal mass or lymphadenopathy, a white blood cell count (WBC) less than 30,000/microL, L1 morphology, T or TMy immunophenotype, and the absence of the Ph chromosome. The estimates of the proportion surviving at 3 years are 69% for patients less than 30 years old, 39% for those 30 to 59 years old, 89% for those who had a mediastinal mass, 59% with WBC less than 30,000/microL, 63% with L1 morphology, 69% for T or TMy antigen expression, and 62% for those who lack the Ph chromosome. Fifteen patients (8%) had no unfavorable prognostic factors and have an estimated probability of survival at 5 years of 100% (95% confidence interval, 77% to 100%). This intensive chemotherapy regimen produces a high remission rate and a high proportion of durable remissions in adults with ALL.  相似文献   
57.
A novel system to study the effects of co-cross-linking CD23/FceRII and sIg on murine B lymphocytes utilizes a highly multivalent form of anti- Ig prepared by covalently linking anti-Ig antibodies to a DNP-dextran backbone. CD23-sIg co-cross-linking is accomplished by the addition of DNP-specific monoclonal IgE. Previous studies demonstrated that co- cross-linking CD23 and sIg significantly inhibited mouse B cell proliferation, especially at high doses of the multivalent anti-Ig. Interestingly, examination of early activation signals reveals no difference in B cells subjected to co-cross-linking conditions as compared to B cells activated with anti-Ig alone. Total cellular protein tyrosine phosphorylation levels are unchanged by co-cross- linking. Analysis of B cell mRNA reveals that co-cross-linking the receptors does not alter the expression levels of ornithine decarboxylase 8 h after stimulation as compared to the controls. In contrast, levels of the proto-oncogene c-myc were significantly elevated 1 h after inducing B cell activation under co-cross-linking conditions. However, it remains unclear whether this aberrant c-myc regulation plays any role in inducing apoptosis. In addition, on day 3 after stimulation, the co-cross-linking of CD23 and sIg resulted in the formation of apoptotic B cells, determined by both photomicroscopy of the B cell cultures and FACS analysis of B cell nuclei. B cells obtained from bcl-2 transgenic mice proliferated as well as controls, and failed to undergo apoptosis when CD23 and sIg were co-cross-linked on their surface. These studies indicate that co-cross-linking of CD23 with B cell sIg inhibits B cell proliferation by a mechanism that is distinct from that seen by co-cross-linking of the Fc gamma RII and sIg. In addition, these results suggest a means by which antigen- specific IgE can down-regulate additional B cell activation and IgE synthesis.   相似文献   
58.
59.
60.
Results of clinical, contrast enema (CE), and computed tomographic (CT) examinations in 39 patients with perforated colorectal neoplasms were retrospectively reviewed. Twenty patients were toxemic at initial presentation, but in only four patients was the diagnosis of perforated colorectal neoplasm initially suspected clinically. CE study was performed in 22 patients and enabled the diagnosis of perforated neoplasm in 11 cases, neoplasm alone in eight, and neither neoplasm nor perforation in three. CT was performed in 38 patients and enabled the diagnosis of perforated neoplasm in 36; pericolic phlegmon but no mass lesion was evident in two. In 16 patients, CT also demonstrated metastatic disease. Because of its reliability in establishing the diagnosis and staging the extent of the inflammatory and neoplastic disease, CT is indicated in cases of suspected or proved perforated colorectal neoplasm and in cases in which CE study findings are indeterminate or suggestive of perforated neoplasm.  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