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   57902篇
  免费   3979篇
  国内免费   228篇
耳鼻咽喉   685篇
儿科学   1472篇
妇产科学   1081篇
基础医学   7248篇
口腔科学   955篇
临床医学   5595篇
内科学   11847篇
皮肤病学   711篇
神经病学   5550篇
特种医学   1945篇
外国民族医学   4篇
外科学   9821篇
综合类   817篇
现状与发展   1篇
一般理论   69篇
预防医学   5131篇
眼科学   1201篇
药学   3557篇
中国医学   62篇
肿瘤学   4357篇
  2023年   221篇
  2022年   423篇
  2021年   995篇
  2020年   558篇
  2019年   948篇
  2018年   1155篇
  2017年   798篇
  2016年   890篇
  2015年   996篇
  2014年   1651篇
  2013年   2440篇
  2012年   3579篇
  2011年   3894篇
  2010年   2191篇
  2009年   2020篇
  2008年   3508篇
  2007年   3688篇
  2006年   3658篇
  2005年   3753篇
  2004年   3681篇
  2003年   3366篇
  2002年   3294篇
  2001年   479篇
  2000年   367篇
  1999年   577篇
  1998年   749篇
  1997年   635篇
  1996年   572篇
  1995年   540篇
  1994年   482篇
  1993年   439篇
  1992年   363篇
  1991年   369篇
  1990年   305篇
  1989年   309篇
  1988年   287篇
  1987年   278篇
  1986年   258篇
  1985年   303篇
  1984年   471篇
  1983年   399篇
  1982年   523篇
  1981年   509篇
  1980年   495篇
  1979年   254篇
  1978年   292篇
  1977年   285篇
  1976年   222篇
  1975年   221篇
  1974年   236篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
Management of pure mucocele‐like lesion (MLL) diagnosed on percutaneous breast biopsy (PBB) is controversial. To assess surgical upgrade rate and clinical outcome of pure MLL obtained as sole diagnosis on PBB. Patients diagnosed with a MLL as the most advanced lesion on PBB from April 1997 to December 2010 were reviewed for radiologic presentation, biopsy technique, and pathologic and clinical outcomes. Of the 21,340 image‐guided PBB performed during the study period, 50 women with 51 MLL (0.24%) were identified. Mean age was 53.1 ± 7.7 years. Radiologic findings were mostly microcalcifications (n = 47, 92.2%). Stereotactic PBB was performed for 49 lesions (96.1%). Surgery was performed shortly after biopsy in 35 women, with benign final pathology in 33, and upgrade to ductal carcinoma in situ (DCIS) in two patients (2/35, 5.7%). Mean follow‐up was 4.2 ± 2.5 years (3.7 ± 2.1 years for surgical patients; 5.9 ± 2.9 years for follow‐up only patients); three women were lost to follow‐up (3/50). Three invasive cancers (3/47, 6.4%) were diagnosed 1.2, 1.2, and 2.8 years after biopsy: two in surgical patients, and one in a follow‐up only patient. No cancer occurred at the same site as the original MLL. Pure MLL lesion of the breast is a rare entity and is mostly associated with a benign outcome. We observed an upgrade to DCIS slightly superior to 5%, but no invasive cancer. It is therefore unclear if these lesions should be excised or clinically and radiologically followed up when such lesions are found at PBB.  相似文献   
995.
996.

Background

Type 1 diabetes patients, although typically lean, experience an increased prevalence of obesity, and bariatric surgery is considered in severe cases. Bariatric surgery in such patients leads to significant weight loss and decreased insulin requirements; however, effects on glycemic control remain discussed. We assessed, in obese patients with type 1 diabetes, the effects of bariatric surgery upon body weight, body composition, and glycemic control, including the occurrence of hypoglycemic events.

Methods

Thirteen obese patients with type 1 diabetes who underwent bariatric surgery (Roux-en-Y gastric bypass n?=?6, sleeve gastrectomy n?=?7) were matched with obese patients without diabetes and with type 2 diabetes patients during 12 months of follow-up. Outcomes included body weight, DXA-assessed body composition, HbA1c, and incidence of hypoglycemia.

Results

At 12 months, median surgery-induced weight loss was 27.9 % (21.1–33.3), 26.1 % (24.8–29.7), and 27.5 % (21.8–32.1) in patients with type 1 diabetes, type 2 diabetes, and without diabetes, respectively, with no significant differences across the groups. Similar findings were observed for body fat changes. At 12 months, median HbA1c decreased from 8.3 to 7.6 % in type 1 diabetes patients versus 8.0 to 5.9 % in type 2 diabetes patients (P?=?0.04 between the groups). In type 1 diabetes patients, the number of reported minor hypoglycemia increased transiently only at 6 months. Two patients reported severe hypoglycemia (one episode each).

Conclusions

Type 1 diabetes patients benefit from bariatric surgery in terms of weight loss and glycemic control. Close monitoring of insulin therapy appears warranted to prevent minor hypoglycemia in the first months post-surgery.
  相似文献   
997.

Background

This study aims to quantify changes in fibroblast growth factor 19 (FGF19) and bile acids (BAs) in patients with uncontrolled type 2 diabetes randomized to Roux-en-Y gastric bypass (RYGB) vs intensive medical management (IMM) and matched for similar reduction in HbA1c after 1 year of treatment.

Methods

Blood samples were drawn from patients who underwent a test meal challenge before and 1 year after IMM (n?=?15) or RYGB (n?=?15).

Results

Mean HbA1c decreased from 9.7 to 6.4 % after RYGB and from 9.1 to 6.1 % in the IMM group. At 12 months, the number of diabetes medications used per subject in the RYGB group (2.5?±?0.5) was less than in the IMM group (4.6?±?0.3). After RYGB, FGF19 increased in the fasted (93?±?15 to 152?±?19 pg/ml; P?=?0.008) and postprandial states (area under the curve (AUC), 10.8?±?1.9 to 23.4?±?4.1 pg?×?h/ml?×?103; P?=?0.006) but remained unchanged following IMM. BAs increased after RYGB (AUC ×103, 6.63?±?1.3 to 15.16?±?2.56 μM?×?h; P?=?0.003) and decreased after IMM (AUC ×103, 8.22?±?1.24 to 5.70?±?0.70; P?=?0.01). No changes were observed in the ratio of 12α-hydroxylated/non-12α-hyroxylated BAs. Following RYGB, FGF19 AUC correlated with BAs (r?=?0.54, P?=?0.04) and trended negatively with HbA1c (r?=??0.44; P?=?0.09); these associations were not observed after IMM.

Conclusions

BA and FGF19 levels increased after RYGB but not after IMM in subjects who achieved similar improvement in glycemic control. Further studies are necessary to determine whether these hormonal changes facilitate improved glucose homeostasis.
  相似文献   
998.
999.

Introduction

Venom immunotherapy (VIT) is the only efficient prevention for sting-induced anaphylaxis, but its application is not without risks and needs precautions and standardization. European guidelines were proposed in 2005, but recent practice surveys and more recent knowledge raise the need for an update. The aim of this study was to analyze VIT practices in France, based on previous surveys in Europe but also extended to outcome event management.

Material and methods

A paper questionnaire was sent widely to persons involved in venom treatment.

Results

Eighty-six responses could be included from physicians actively involved in VIT induction evenly distributed in France. The survey shows that VIT was engaged from grade III down to grade I reactions, starting preferentially with the ultra-rush protocol. Premedication was used by 42% only and risks induced by co-treatment with β-blockers were well known but not with angiotensin-converting enzyme inhibitors. However, side effects were very variably managed from arrest to enhancement in doses, time-delay or duration. Similarly, we observed a large discrepancy in treatment evaluation (skin tests, biology, timing and interpretation), decision making for treatment termination (when and how long to be prolonged) and post-treatment follow-up (adrenaline kit, event record) as well as procedures in case of late relapse (new induction, different doses).

Conclusions

Our study shows that most recommendations were fully or partially followed and may need reminding, but many points need to be completed or updated with new tools and knowledge acquired during the last 10 years.  相似文献   
1000.
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