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   368727篇
  免费   50877篇
  国内免费   643篇
耳鼻咽喉   5331篇
儿科学   13315篇
妇产科学   7165篇
基础医学   56156篇
口腔科学   11922篇
临床医学   34116篇
内科学   87928篇
皮肤病学   15025篇
神经病学   38378篇
特种医学   10533篇
外国民族医学   129篇
外科学   50132篇
综合类   1369篇
一般理论   96篇
预防医学   31158篇
眼科学   6789篇
药学   25711篇
中国医学   1914篇
肿瘤学   23080篇
  2023年   1602篇
  2022年   2053篇
  2021年   6663篇
  2020年   7846篇
  2019年   15867篇
  2018年   17917篇
  2017年   16072篇
  2016年   16790篇
  2015年   17335篇
  2014年   18423篇
  2013年   23108篇
  2012年   23364篇
  2011年   23446篇
  2010年   18413篇
  2009年   13220篇
  2008年   18600篇
  2007年   18648篇
  2006年   17490篇
  2005年   17291篇
  2004年   16108篇
  2003年   14965篇
  2002年   14318篇
  2001年   8945篇
  2000年   8986篇
  1999年   7548篇
  1998年   1717篇
  1997年   1364篇
  1996年   1246篇
  1995年   1126篇
  1992年   3986篇
  1991年   3636篇
  1990年   3428篇
  1989年   3057篇
  1988年   2859篇
  1987年   2711篇
  1986年   2573篇
  1985年   2352篇
  1984年   1741篇
  1983年   1466篇
  1979年   1501篇
  1978年   1056篇
  1977年   964篇
  1975年   1035篇
  1974年   1234篇
  1973年   1236篇
  1972年   1165篇
  1971年   1153篇
  1970年   1099篇
  1969年   1126篇
  1968年   988篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
21.
22.

Background

We have recently shown that human epididymis protein 4 (HE4) levels correlate with the severity of cystic fibrosis (CF) lung disease. However, there are no data on how HE4 levels alter in patients receiving CFTR modulating therapy.

Methods

In this retrospective clinical study, 3 independent CF patient cohorts (US-American: 29, Australian: 12 and Irish: 19 cases) were enrolled carrying at least one Class III CFTR CF-causing mutation (p.Gly551Asp) and being treated with CFTR potentiator ivacaftor. Plasma HE4 was measured by immunoassay before treatment (baseline) and 1–6?months after commencement of ivacaftor, and were correlated with FEV1 (% predicted), sweat chloride, C-reactive protein (CRP) and body mass index (BMI).

Results

After 1?month of therapy, HE4 levels were significantly lower than at baseline and remained decreased up to 6?months. A significant inverse correlation between absolute and delta values of HE4 and FEV1 (r?=??0.5376; P?<?.001 and r?=??0.3285; P?<?.001), was retrospectively observed in pooled groups, including an independent association of HE4 with FEV1 by multiple regression analysis (β?=??0.57, P?=?.019). Substantial area under the receiver operating characteristic curve (ROC-AUC) value was determined for HE4 when 7% mean change of FEV1 (0.722 [95% CI 0.581–0.863]; P?=?.029) were used as classifier, especially in the first 2?months of treatment (0.806 [95% CI 0.665–0.947]; P?<?.001).

Conclusions

This study shows that plasma HE4 levels inversely correlate with lung function improvement in CF patients receiving ivacaftor. Overall, this potential biomarker may be of value for routine clinical and laboratory follow-up of CFTR modulating therapy.  相似文献   
23.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges.  相似文献   
24.
We report the case of a littoral‐cell angioma of the spleen, a recently described benign vascular tumour, whose imaging and pathological characteristics have been discussed only by a few authors. The diagnosis was made after elective splenectomy. The CT images, scintigraphy and histological specimens are presented, and differential diagnoses discussed.  相似文献   
25.
Multi-day signals, generally with duration of 2-10 days, are a prominent temporal variation type of radon (Rn) in geogas in the unsaturated zone. Rare multi-day Rn signals have been found which are characterized by: (a) a declining limb lasting up to 10 days which conforms to the radioactive decay of Rn, (b) recurs at the same location and (c) is recorded in diverse situations-volcanic and seismogenic. It suggested that a Rn blob is injected at a lower level on a steady upward flow of geogas whereby the rise and final fall of the signal are attributed to the edges of the blob while the central Rn-decay segment records the passing of the decaying blob itself. Rn-decay signals are a small subset of multi-day Rn signals which are considered as highly irregular and unusable for the understanding of geophysical processes. In difference, it is concluded that multi-day Rn signals are probably proxies of subtle geodynamic processes at upper crustal levels and are therefore significant for studying such processes.  相似文献   
26.
27.
Allergoid immunotherapy is a new form of allergen immunotherapy allowing safe administration of high allergen doses. There is limited information on the effects of allergoid immunotherapy in children with allergic rhinitis. To investigate the immunological and clinical effects of allergoid immunotherapy in children with allergic rhinitis due to grass pollen allergy. Children with allergic rhinitis were assigned to allergoid immunotherapy (n = 27) or control (n = 26, no immunotherapy) groups. Children in the immunotherapy group received seven injections of grass pollen allergoid immunotherapy before grass pollen season and continued to receive maintenance immunotherapy for 27 months. All patients were offered a pharmacotherapy regimen to be used on demand during the pollen seasons. Clinical and laboratory parameters were compared between the immunotherapy and control groups. The rhinoconjunctivitis symptom-medication score and asthma symptom score were lower in the immunotherapy group after 1 yr of maintenance immunotherapy (p < 0.01 for both). Skin test reactivity and nasal reactivity as determined by nasal provocation testing for grass pollen were significantly decreased after 1 yr of immunotherapy (p < 0.001 for both). The seasonal increase in bronchial reactivity and nasal lavage eosinophil cationic protein levels were prevented after the first year of immunotherapy (p < 0.05 for both). The seasonal increase in immunoglobulin (Ig)E decreased (p < 0.05) and grass-specific IgG, IgG(1) and IgG(4) increased significantly already at the end of the seven-injection build-up therapy (p < 0.001, for all). Interleukin (IL)-4 levels in the culture supernatants showed a steady decline from baseline at first and second year of immunotherapy (p < 0.001) but remained unchanged in the control group. Allergoid immunotherapy is an effective method in the treatment of grass pollen-induced allergic rhinitis in children and prevents the seasonal increase in bronchial hyper-reactivity. Changes in specific IgE and IgG levels and decreased IL-4 production in peripheral blood mononuclear cell culture supernatants may account for the observed clinical effects.  相似文献   
28.
29.
30.
Purpose:  To evaluate all consecutive patients treated with infliximab for hidradenitis suppurativa (HS).
Patients and methods:  Within 1 year, all consecutive patients seen in our department for HS (1) resistant to usual medical therapies (2) which could not be easily cured by surgery (3) not treated with new medication within 2 months before inclusion were treated intravenously with infliximab (5 mg/kg) without corticosteroids premedication. Four infusions were planned (week 0, week 2, week 6 and week 10) before the interruption of therapy and follow-up. Clinical activity of HS and quality of life of the patients were assessed immediately before the first, the third and the fourth infusions of infliximab.
Results:  Seven patients were included. Five completed the four infusions. Two patients received only three infusions because of severe side effects. The Sartorius score moderately improved with infliximab (mean score at week 0: 94 ± 39, at week 6: 71 ± 38 and at week 10: 83 ± 48). At week 6, patients judged the efficacy of therapy as marked ( n  = 1), moderate ( n  = 4) or null ( n  = 2). At week 10, five patients were evaluated and judged this efficacy as marked ( n  = 2), moderate ( n  = 2) or null ( n  = 1). The mean Skindex-29 score varied from 22 ± 11 (E: 25 ± 9, S: 13 ± 5, F: 28 ± 12) at week 0 to 18 ± 10 (E: 22 ± 8, S: 12 ± 8, F: 22 ± 12) at week 10.
Conclusion:  The efficacy of infliximab in severe HS is partial. More experience is needed before finding a place for infliximab in the therapeutic armamentarium for HS.  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