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   16569篇
  免费   1202篇
  国内免费   58篇
耳鼻咽喉   282篇
儿科学   436篇
妇产科学   412篇
基础医学   2580篇
口腔科学   467篇
临床医学   1701篇
内科学   3169篇
皮肤病学   315篇
神经病学   1482篇
特种医学   661篇
外国民族医学   1篇
外科学   2247篇
综合类   197篇
一般理论   51篇
预防医学   1372篇
眼科学   414篇
药学   1140篇
中国医学   17篇
肿瘤学   885篇
  2022年   76篇
  2021年   259篇
  2020年   138篇
  2019年   255篇
  2018年   305篇
  2017年   240篇
  2016年   269篇
  2015年   314篇
  2014年   412篇
  2013年   753篇
  2012年   901篇
  2011年   1074篇
  2010年   586篇
  2009年   512篇
  2008年   916篇
  2007年   969篇
  2006年   898篇
  2005年   897篇
  2004年   960篇
  2003年   865篇
  2002年   923篇
  2001年   173篇
  2000年   143篇
  1999年   184篇
  1998年   234篇
  1997年   200篇
  1996年   176篇
  1995年   159篇
  1994年   157篇
  1993年   135篇
  1992年   105篇
  1991年   93篇
  1990年   84篇
  1989年   96篇
  1988年   95篇
  1987年   99篇
  1986年   84篇
  1985年   108篇
  1984年   124篇
  1983年   93篇
  1982年   162篇
  1981年   129篇
  1980年   130篇
  1979年   73篇
  1978年   85篇
  1977年   79篇
  1976年   70篇
  1974年   75篇
  1973年   59篇
  1963年   55篇
排序方式: 共有10000条查询结果,搜索用时 203 毫秒
51.
52.
Osteomyelitis was induced in the radius in 77 rabbits and confirmed by histological examination and culture. At 4 weeks, the wounds were debrided and the animals were treated with (a) fatty acid dimersebacic acid beads (a bioerodable composite) impregnated with 20% or (b) 10% gentamicin sulfate, (c) placebo beads and intramuscular gentamicin sulfate. (d) placebo beads alone, or (e) debridement only. After 4 weeks, eradication of infection was determined by histological examination and culture. Osteomyelitis was eradicated in 93% of the animals treated with the beads and 20% gentamicin, in 67% of those treated with the beads arid 10% gentamicin, in 25% of those treated with placebo beads and intramuscular gentamicin, in 7% of those treated with placebo beads alone, and in 12.5% of those treated with debridement only (p values from <0.001 to 0.02). Fatty acid dimer-sehacie acid beads with gentamicin were then implanted in noninfected rabbits, and gentamicin sulfate concentrations in bone, serum, urine, and wound exudate were measured. Gentamicin sulfate was detectable in bone for as long as 8 weeks after implantation. Levels as high as 4,746 g/ml were present in the wound exudate for the first 7 days. Levels in the serum peaked at 1.03 μg/ml. Urine levels peaked at 135 μg/ml.  相似文献   
53.
54.
Pregnant mice were exposed to one of five regimens at 9.5 days of gestation: no treatment (group 1), intraperitoneal injection of normal saline (group 2), intraperitoneal injection of gadopentetate dimeglumine (group 3), intraperitoneal injection of gadopentetate dimeglumine and magnetic resonance (MR) exposure (group 4), and MR exposure alone (group 5). At 18 days of gestation, the mice were sacrifice and fetuses were removed and examined for the following end points: litter size, number alive or dead, fetal weight, extremity morphology, eye and ear development, and appearance of the head. A total of 739 fetuses were analyzed: group 1 (n = 161), group 2 (n = 149), group 3 (n = 142), group 4 (n = 136), and group 5 (n = 151). The only statistically significant difference was a lower mean fetal weight in the saline-injection group compared with the control group. The results show that MR exposure with and without gadopentetate dimeglumine had no adverse effect on the end points analyzed.  相似文献   
55.
Role of substance P in several models of bladder inflammation   总被引:1,自引:0,他引:1  
Substance P (SP) is a peptide found in the sensory nervous system which has multiple biologic effects including stimulation of muscle contraction, pain nociception, immune cell functions, plasma extravasation and a constellation of inflammatory effects. Here we investigate the role of SP in several animals models of bladder inflammation. Using the female Lewis rat, inflammation was induced using either xylene, lipopolysaccharide (LPS) or polyinosinic-polycytidylic acid (polyIC). Inflammation occurred rapidly (4 h) and was maintained in each model for at least 7 days. Each of these protocols decreased the bladder content of immunoreactive SP by approximately 50%, suggesting enhanced release. There was no change in the urinary frequency of these animals over 3 weeks, suggesting that urinary frequency changes are not mediated by acute inflammation. We also found that the SP receptor (NK1) antagonist, (?)CP96345, was unable to block the inflammation produced by polyIC, suggesting that SP is not an obligatory mediator of immune cell stimulation in this model.  相似文献   
56.
57.
This study presents an analysis on longitudinal tumour marker series in twenty-two patients with non-seminomatous germ cell cancers treated with cisplatinum (DDP) based combination chemotherapy. Series of alphafoetoprotein (AFP), human chorionic gonadotropin (HCG) and lactate dehydrogenase (LDH) were analyzed applying a dynamic mathematical marker model. The model analysis provided quantitated values for growth rate and treatment response in the marker producing cells. The analysis showed that LDH had to be above 2 000 U/l to be a trustworthy tumour marker. HCG producing cells tended to grow faster than AFP producing cells, and were 3-5-fold more sensitive to the chemotherapy given than AFP producing cells. Treatment response versus DDP dose appeared to be bi-phasic, but with no significant change in treatment efficiency within the given range of DDP doses.  相似文献   
58.
59.
Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia.  相似文献   
60.
Background. Although it has been established that basal cell carcinoma is an uncommon diagnosis in black patients, the morpheaform subtype is very rare among these individuals.
Objective. The objective is to present two cases of morpheaform basal cell carcinoma in African-American patients.
Methods. This is a case series and a literature review using the Ovid Medline Database. Key words used in the search include "basal cell carcinoma,""African American,""black,""African,""negros,""morpheaform,""sclerosing,""fibrosing," and "scar-like basal cell carcinoma." The Ovid Medline Database was searched from 1966 to present and was restricted to the English language.
Results. A review of the Emory Dermatology clinic charts from 1989 to 2004 revealed two black patients with morpheaform basal cell carcinomas.
Conclusions. Although extremely rare, morpheaform pattern basal cell carcinoma must be considered in the differential diagnosis for black patients presenting with nonhealing lesions.  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