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   5976篇
  免费   277篇
  国内免费   9篇
耳鼻咽喉   24篇
儿科学   134篇
妇产科学   195篇
基础医学   736篇
口腔科学   70篇
临床医学   452篇
内科学   1506篇
皮肤病学   72篇
神经病学   541篇
特种医学   355篇
外科学   990篇
综合类   20篇
一般理论   8篇
预防医学   413篇
眼科学   87篇
药学   284篇
中国医学   4篇
肿瘤学   371篇
  2023年   26篇
  2022年   42篇
  2021年   89篇
  2020年   78篇
  2019年   109篇
  2018年   95篇
  2017年   93篇
  2016年   116篇
  2015年   125篇
  2014年   190篇
  2013年   282篇
  2012年   437篇
  2011年   515篇
  2010年   292篇
  2009年   275篇
  2008年   398篇
  2007年   455篇
  2006年   365篇
  2005年   416篇
  2004年   366篇
  2003年   322篇
  2002年   291篇
  2001年   71篇
  2000年   36篇
  1999年   50篇
  1998年   68篇
  1997年   73篇
  1996年   64篇
  1995年   43篇
  1994年   51篇
  1993年   45篇
  1992年   31篇
  1991年   34篇
  1990年   30篇
  1989年   16篇
  1988年   28篇
  1987年   28篇
  1986年   28篇
  1985年   24篇
  1984年   17篇
  1983年   17篇
  1982年   19篇
  1981年   14篇
  1980年   14篇
  1979年   11篇
  1978年   17篇
  1977年   12篇
  1975年   7篇
  1974年   11篇
  1973年   4篇
排序方式: 共有6262条查询结果,搜索用时 0 毫秒
1.
We prospectively enrolled 160 consecutive patients with inversion trauma of the ankle in a diagnostic protocol that included physical examination within 2 days and at 5 days after trauma, arthrography, stress radiography, and ultrasonography. 135 patients had pathological lateral ligament laxity on the later physical examination or lateral ligament rupture diagnosed on arthrography and they were operated on. 122 of these patients had ligament ruptures.

At clinical follow-up after a minimum of half a year, all of the patients who were not operated on had stable joints without signs of previous ligament ruptures.

Delayed physical examination at 5 days after the injury led to the highest overall sensitivity (96%) and specificity (84%) for the detection of a ligament rupture. Additional diagnostic procedures, at a considerable cost, yielded little additional information.  相似文献   
2.
3.
In the past few years several studies have supported an interplay between cytomegalovirus infections and a prothrombotic state. We describe a case of primary cytomegalovirus infection in an immunocompetent adult that was complicated with mesenteric vein thrombosis. Transient protein C deficiency, lupus anticoagulant and activated protein C resistance were found, in combination with a heterozygous prothrombin G20210A mutation. We discuss the possible mechanisms of cytomegalovirus-related venous thrombosis.  相似文献   
4.
Summary A patient is described with a testicular Non-Hodgkin's Lymphoma (NHL) presenting with panhypopituitarism caused by a hypophyseal localization. A67Gallium scintigraphy showed avid uptake in the hypophyseal region. Obviously67Gallium could reach the tumor, by the intravenous route, which was the reason to treat the patient with intravenous chemotherapy. A complete remission was induced, which seems to be lasting (+ 25 months). As far as we know this is the first report of panhypopituitarism caused by a hypophyseal NHL in the hypophysis and successfully treated by intravenous chemotherapy.  相似文献   
5.
Case report of a very large ectasia of the urethra in a 9 years old boy without any organic conflict and without any neuro-urologic trouble. It could be a particular syndrome.  相似文献   
6.
Background: It is often difficult to detect a local recurrence of soft-tissue sarcomas due to disturbance of the normal anatomy by previous surgery and radiotherapy. The aim of this study was to assess the value of positron emission tomography (PET) with [18F]fluoro-2-deoxy-d-glucose (FDG) for detecting local recurrences. Methods: In the period 1992–1995, 17 patients with proven or suspected local recurrence of soft-tissue sarcoma were examined using FDG-PET. Fifteen of these patients were ultimately proven to have a recurrence. Results: Recurrence was visualized in 14 patients (93%). Small tumors (maximum diameter 0.5 cm) were as easily visible as large lesions (maximum diameter 20 cm). In one patient the PET scan was positive, but the recurrence could not be proven histologically. Recurrence was proven 1 year later. A recurrent low-grade liposarcoma was not visualized. The two patients with benign lesions had a negative PET scan. The mean glucose metabolic rate was calculated to be 13.2 μmol/100 g/min (range 1.9–28.4). A correlation was found between the histological malignancy grade and the metabolic rate (p<0.05; Kruskal-Wallis). Conclusion: PET with FDG is a useful addition to the diagnostic armamentarium for detecting local recurrence of soft-tissue sarcomas and provides an indication of the malignancy grade of the recurrent lesion. Presented at the 47th Annual Meeting of The Society for Surgical Oncology, Houston, Texas, March 17–20, 1994.  相似文献   
7.
Bis[di-n-butyl (4-aminosalicylato)tin] oxide [NSC: 628561] (compound 1), bis [diphenyl(4-aminosalicylato)tin] oxide [NSC: 628562] (compound 2), and six other analogous compounds of the type [n-Bu2 (XYZ-C6H2COO)Sn]2O (compounds 3 to 8), were tested in vitro at the National Cancer Institute, Bethesda, Maryland, USA, for cytotoxic activity against a series of human cell lines. Compounds 1, 6 and 8 score globally satisfactorily since four of the five relevant sensitivity or selectivity parameters, DGI50, DTGI or DLC50, DH and MGDH, are statistically significant. Compounds 3 and 7 are less satisfactory because only three such parameters are statistically significant. For compound 2, only two of the parameters are significant.  相似文献   
8.
SYNOPSIS
Relationships between precipitating factors in the pathogenesis of migraine were studied in a sample of 217 migraineurs. The most frequently cited triggers were the menstrual cycle (51.5% of the women), alcoholic beverages (51.6%) and emotional or psychic stress (48.8%). Analysis of 4 subgroups of patients, i.e. those with only one of these 3 triggers or with none of these (controls), showed that alcohol-susceptible patients reported significantly (p<0.001) more alimentary triggers than the controls. A similar phenomenon was found in patients with menstrual-cycle related migraine, but in this group the difference with the controls fell short of reaching statistical significance. A further analysis showed that menstrual migraine attacks are more frequently preceded by depressive symptoms than other migraine attacks.
It is suggested that the gut of certain migraineurs may be unduly permeable, either intrinsically or extrinsically (e.g. under the influence of alcohol). In addition, in some patients with menstrual migraine, a depressive episode, associated with the menstrual period, may facilitate the development of a migraine attack.  相似文献   
9.
CHIP (325 mg/M2), a second generation cisplatin derivative, was administered intravenously every 3 weeks to 85 pediatric patients with recurrent sarcomas (19), osteosarcomas (20), neuroblastoma (23), germ cell tumors (10), and other malignant tumors (7). Thirty-eight of them had been previously exposed to cisplatin. Partial remissions were only observed in 3 of 23 (13% SE=7%) patients having neuroblastoma. Severe thrombocytopenia (65%) and neutropenia (35%) were the dose limiting factors.  相似文献   
10.
We investigated four acrylic cement preparation techniques for their effects on cement porosity: hand mixing, pressurization in a pneumatic pistol, centrifugation, and vacuum mixing. All the techniques were tested on three types of cement with different viscosity characteristics. The best results were obtained with vacuum mixing using a newly designed experimental system, yielding porosity reductions of 60-80 percent relative to hand mixing. Vacuum mixing with a commercial system was also effective, but to a somewhat lesser extent.

Pressurization and centrifugation had no substantial effect on the overall porosity. Centrifugation led to considerable nonuniformity in the distribution of pores and additives.  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