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   618篇
  免费   35篇
  国内免费   1篇
耳鼻咽喉   1篇
儿科学   23篇
妇产科学   21篇
基础医学   92篇
口腔科学   18篇
临床医学   40篇
内科学   156篇
皮肤病学   15篇
神经病学   19篇
特种医学   14篇
外科学   112篇
综合类   8篇
预防医学   39篇
眼科学   22篇
药学   34篇
中国医学   1篇
肿瘤学   39篇
  2023年   5篇
  2022年   6篇
  2021年   17篇
  2020年   10篇
  2019年   7篇
  2018年   18篇
  2017年   8篇
  2016年   7篇
  2015年   17篇
  2014年   35篇
  2013年   26篇
  2012年   49篇
  2011年   79篇
  2010年   32篇
  2009年   23篇
  2008年   46篇
  2007年   61篇
  2006年   41篇
  2005年   31篇
  2004年   21篇
  2003年   25篇
  2002年   27篇
  2001年   1篇
  2000年   5篇
  1999年   2篇
  1998年   4篇
  1997年   3篇
  1996年   2篇
  1995年   2篇
  1994年   4篇
  1993年   6篇
  1992年   6篇
  1991年   1篇
  1990年   1篇
  1989年   1篇
  1988年   2篇
  1987年   3篇
  1986年   4篇
  1985年   3篇
  1984年   1篇
  1983年   2篇
  1982年   2篇
  1981年   3篇
  1978年   2篇
  1977年   1篇
  1976年   2篇
排序方式: 共有654条查询结果,搜索用时 46 毫秒
41.
42.
The objective of this review was to summarize the current literature of community-based colorectal cancer screening randomized controlled trials with multi-ethnic groups. The CDC reports 40% of adults do not receive time-appropriate colorectal cancer screening. Although overall screening rates have improved since 2000, disparities remain. Studies examining community characteristics may offer insight into improving screening rates and eliminating disparities. We identified community-based colorectal cancer screening studies using PubMed and Ovid Medline database searches. Inclusion criteria were: community-based, randomized controlled trials; English language; published from 1/2001 to 8/2009; all colorectal cancer screening test interventions recommended in the 2008 “Joint Consensus” report; and study participants from at least two racial/ethnic groups, with not more than 90% representation from one group. There were 29 relevant articles published during 2001–2009; with 15 meeting inclusion criteria. We categorized the final studies (n = 15) into the four categories of Patient mailings (n = 3), Telephone outreach (n = 3), Electronic/multimedia (n = 4), and Counseling/community education (n = 5). Of 15 studies, 11 (73%) demonstrated increased screening rates for the intervention group compared to controls, including all studies (100%) from the Patient mailings and Telephone outreach groups, 4 of 5 (80%) Counseling/community education studies, and 1 of 4 (25%) Electronic/multimedia interventions. Patient choice and tailoring of information were common features of trials that increased screening rates across study categories. Including community-level factors and social context may be useful in future design and evaluation of colorectal cancer interventions to reduce or prevent new cases of colorectal cancer.  相似文献   
43.
44.
The secretory prohormone chromogranin A (CHGA) is overexpressed in essential hypertension, a complex trait with genetic predisposition, while its catecholamine release-inhibitory fragment catestatin is diminished, and low catestatin predicts augmented adrenergic pressor responses. These findings from studies on humans suggest a mechanism whereby diminished catestatin might increase the risk for hypertension. We generated Chga and humanized mice through transgenic insertion of a human CHGA haplotype in order to probe CHGA and catestatin in vivo. Chga mice displayed extreme phenotypic changes, including: (a) decreased chromaffin granule size and number; (b) elevated BP; (c) loss of diurnal BP variation; (d) increased left ventricular mass and cavity dimensions; (e) decreased adrenal catecholamine, neuropeptide Y (Npy), and ATP contents; (f) increased catecholamine/ATP ratio in the chromaffin granule; and (g) increased plasma catecholamine and Npy levels. Rescue of elevated BP to normalcy was achieved by either exogenous catestatin replacement or humanization of Chga mice. Loss of the physiological "brake" catestatin in Chga mice coupled with dysregulation of transmitter storage and release may act in concert to alter autonomic control of the circulation in vivo, eventuating in hypertension.  相似文献   
45.
In studies primarily confined to the amino-terminal region of the fibrillar group A streptococcal M protein, only limited immunological crossreactions have been observed among M serotypes. In this investigation, two monoclonal antibodies generated against nearly the entire M6 molecule (LysM6) were used to determine the extent of crossreactions among M serotyping strains and to localize their epitopes on the M molecule. Colony blot and immunoblot analyses revealed that an epitope responsible for crossreactions among 5 of the 56 strains of different M serotypes tested is located in the amino-terminal half of the molecule, distal to the cell surface. In contrast, a more common crossreactive epitope, reacting with 20 of the 56 strains, is located near the middle of the M molecule. These studies also reveal that the more conserved determinant, located more proximally to the cell surface, is accessible to the immune system, even on the whole organism, and, thus, may be useful in devising means to protect against infections by multiple group A streptococcal M serotypes.  相似文献   
46.
Macrophage activation syndrome (MAS) is a clinical syndrome caused by an excessive proliferation of T lymphocytes and well-differentiated macrophages; an entity distinct from malignant histiocytosis. Although rheumatologic conditions are the common cause of MAS, a wide range of infections are also seen to cause MAS. We report an adolescent with severe Plasmodium falciparum malaria and MAS. He fulfilled six out of eight criteria required to diagnose hemophagocytic lymphohistiocytosis.  相似文献   
47.
48.
This study was carried out to obtain information on the efficacy and safety of the controlled release formulation of the doxazosin Gastrointestinal Therapeutic System (GITS) in Taiwanese subjects with benign prostatic hyperplasia (BPH). Studies of doxazosin in Asian populations for this indication have lacked data particularly from Taiwan. This was an 8-week, post-marketing, open-label, non-comparative study. Eighty male subjects (mean age=64 years) with BPH received doxazosin GITS 4 mg once daily. At week 4, subjects who achieved an increase in maximum urinary flow rate (Qmax) of ≥3mL/s and a ≥30% reduction in the total International Prostate Symptom Score (IPSS) continued on doxazosin GITS 4 mg for the remaining 4 weeks; all other subjects were up-titrated to 8 mg once daily. Change from baseline at weeks 4 and 8 (primary endpoint) in IPSS and Qmax was evaluated using two-sided paired t tests for the intent-to-treat population. Safety was assessed throughout the study. A total of 53 (66.3%) subjects completed the study. Baseline Qmax and IPSS were 10.7+3.4 mL/s and 20.6+5.4, respectively. At week 8, a significant increase from baseline in Qmax of 3.3+4.6 mL/s (95% confidence interval = 2.2-4.4, p< 0.001) and a significant decrease in total IPSS of -8.9 + 7.0 (95% confidence interval=-10.5 to -7.3, p< 0.001) was observed. The most common treatment-related adverse event was dizziness. Doxazosin GITS 4 mg per day (with an 8-mg titration step) effectively improved symptoms of BPH. The results from this study provide further information for clinicians on the use of doxazosin GITS for the treatment of BPH, particularly in Taiwanese patients.  相似文献   
49.
A large program was conducted by the Government of India to study the prevalence and profile of chronic hepatitis B virus (HBV) infection and its risk factors in pregnant women attending a tertiary care hospital in India. From September 2004 to December 2008 consecutive pregnant women attending the antenatal clinic were screened and those found positive for HBsAg were enrolled. Healthy non‐pregnant women of child‐bearing age, who presented for blood donation during the same period, served as controls. Women with symptoms of liver disease or those aware of their HBsAg status were excluded. Of the 20,104 pregnant women screened, 224 (1.1%) and of the 658 controls, 8 (1.2%) were HBsAg positive (P = ns). Previous blood transfusions and surgery were significant risk factors for infection with HBV. Of the women who were HBsAg positive, the ALT levels were normal in 54% of the women and HBV DNA levels were above 2,000 IU/ml in 71% of women. The median HBV DNA levels were higher in women who were HBeAg positive compared to the HBeAg negative group. The most common HBV genotype was D (84%) followed by A + D and A (8% each). In conclusion, the prevalence of HBsAg positivity among asymptomatic pregnant women in North India is 1.1% with 71% having high HBV DNA levels. These women may have a high risk of transmitting infection to their newborns. J. Med. Virol. 83:962–967, 2011. © 2011 Wiley‐Liss, Inc.  相似文献   
50.
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