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   1434篇
  免费   68篇
  国内免费   4篇
耳鼻咽喉   17篇
儿科学   105篇
妇产科学   27篇
基础医学   206篇
口腔科学   28篇
临床医学   152篇
内科学   231篇
皮肤病学   25篇
神经病学   75篇
特种医学   45篇
外国民族医学   1篇
外科学   120篇
综合类   37篇
一般理论   1篇
预防医学   106篇
眼科学   69篇
药学   127篇
中国医学   7篇
肿瘤学   127篇
  2023年   13篇
  2022年   39篇
  2021年   68篇
  2020年   33篇
  2019年   50篇
  2018年   46篇
  2017年   36篇
  2016年   47篇
  2015年   53篇
  2014年   73篇
  2013年   96篇
  2012年   139篇
  2011年   122篇
  2010年   64篇
  2009年   42篇
  2008年   90篇
  2007年   93篇
  2006年   79篇
  2005年   56篇
  2004年   77篇
  2003年   51篇
  2002年   62篇
  2001年   9篇
  2000年   5篇
  1999年   7篇
  1998年   10篇
  1997年   5篇
  1996年   3篇
  1995年   1篇
  1994年   4篇
  1993年   6篇
  1992年   2篇
  1991年   1篇
  1990年   1篇
  1989年   5篇
  1988年   2篇
  1987年   4篇
  1984年   1篇
  1983年   2篇
  1981年   2篇
  1980年   2篇
  1977年   1篇
  1948年   1篇
  1930年   1篇
  1929年   1篇
  1922年   1篇
排序方式: 共有1506条查询结果,搜索用时 15 毫秒
81.
82.
83.
OBJECTIVE: This analysis assessed the incidence, severity, onset, and duration of nausea among patients with major depressive disorder (MDD) treated with the new antidepressant duloxetine. METHODS: Data were pooled from 8 double-blind, randomized, placebo- and active comparator-controlled trials employing patients with MDD that were submitted to the US Food and Drug Administration to support duloxetine's new drug application for treatment of MDD. RESULTS: The numbers of patients receiving each regimen were as follows: placebo, n = 777; duloxetine 40 mg/d, n = 177; duloxetine 60 mg/d, n = 251; duloxetine 80 mg/d, n = 363; duloxetine 120 mg/d, n = 348; paroxetine 20 mg/d, n = 359; and fluoxetine 20 mg/d, n = 70. In acute placebo-controlled trials of duloxetine 40 to 120 mg/d, treatment-emergent nausea was reported by more duloxetine-treated patients than those receiving placebo (19.9% [227/1139] vs 6.9% [154/777], respectively; P <0.001). Among duloxetine-treated patients, the median time to onset of nausea was 1 day, and the median duration of nausea was 7 days. The incidence of nausea was similar to placebo rates after 1 week. In paroxetine-controlled studies, the incidence of treatment-emergent nausea in patients receiving duloxetine did not differ significantly from paroxetine (14.4% vs 12.0%, respectively). In head-to-head studies, the incidence of treatment-emergent nausea with duloxetine did not differ significantly from that with fluoxetine (17.1% vs 15.7%, respectively). Most duloxetine-treated patients reported nausea to be mild (52.9%) or moderate (41.4%). Treatment discontinuation secondary to nausea occurred in more duloxetine-treated patients than those receiving placebo (1.4% [16/1139] vs 0.1% [1/777], respectively; P = 0.002). Following abrupt discontinuation after acute treatment, 5.9% of duloxetine-treated patients exhibited nausea compared with 0.3% of patients receiving placebo (P < 0.001). The incidence of treatment-emergent nausea during 6-month continuation of duloxetine treatment (80 mg/d, 2.1%; 120 mg/d, 1.3%) was similar to placebo (1.6%). Following abrupt discontinuation after 8 months of treatment, nausea was reported by 1.6% of patients receiving duloxetine 120 mg/d compared with 0% for those receiving duloxetine 80 mg/d and 0% for placebo. CONCLUSIONS: Duloxetine induced mild to moderate nausea in a subset of patients with MDD during treatment initiation. Nausea resolved rapidly with continued treatment. The incidence of duloxetine-induced nausea resembled that produced by paroxetine and fluoxetine.  相似文献   
84.
BACKGROUND: The 1985 FAO/WHO/UNU requirement for methionine in healthy adults consuming a cystine-free diet is 13 mg.kg(-1).d(-1). It is unclear whether this daily requirement is influenced by dietary cystine. OBJECTIVE: We assessed the effect of 2 intakes of cystine (5 and 12 mg.kg(-1).d(-1)) on methionine requirements in well-nourished Indian men by using 7 test methionine intakes (3, 6, 9, 13, 18, 21 and 24 mg.kg(-1).d(-1)) and the 24-h indicator amino acid oxidation (24-h IAAO) and balance (24-h IAAB) methods. We combined these data with those from an experiment with zero cystine intake and in which the exact same method was used. DESIGN: Two studies were performed in which a diet containing either 5 or 12 mg cystine.kg(-1).d(-1) was fed to 21 well-nourished Indian men over three 7-d periods. The 24-h IAAO and 24-h IAAB values were measured on day 7 with the use of a 24-h intravenous [13C]leucine tracer infusion. The breakpoints in the relation between these values and methionine intake in each study were assessed by two-phase linear regression. RESULTS: Breakpoints in the response curve were obtained at methionine intakes of 20 (95% Fiellers CI: 17, 26) and 10 (95% Fiellers CI: 8, 16) mg.kg(-1).d(-1) with cystine intakes of 5 and 12 mg.kg(-1).d(-1) intakes, respectively, which suggested a sparing effect of cystine. Although the 5- and 12-mg cystine breakpoints differed from one another, they did not differ significantly from that estimated previously with 0 mg cystine. CONCLUSION: Cystine may spare the methionine requirement in healthy men, although the amount of sparing is difficult to quantify.  相似文献   
85.
Orbital apex syndrome secondary to mucormycosis in immuno-compromised patients is well described; however, few reports exist of a paranasal sinus mycetoma resulting in this presentation in the immuno-competent patient. The case is reported of a 92-year-old man who developed orbital apex syndrome secondary to a sphenoidal sinus mycetoma of Pseudallescheria boydii.  相似文献   
86.
A prevailing view in neuroscience is that the mature CNS has relatively little capacity to respond adaptively to injury. Recent data indicating a high degree of structural plasticity in the adult brain provides an impetus to reexamine how central neurons react to trauma. An analysis of both in vivo and in vitro experimental studies demonstrates that certain brain neurons may have an intrinsic ability to respond to structural injury by an attempt at regenerative sprouting. Indeed, aberrant sprouting following neuronal injury may be the cause of epilepsy following brain trauma and may underlie the neuronal changes stimulated by plaque formation in Alzheimer's disease. An understanding of the stereotypical reaction to injury of different CNS neurons, as well as the role of nonneuronal cells, may provide new avenues for therapeutic intervention for a range of neurodegenerative diseases and "acquired" forms of CNS injury.  相似文献   
87.
88.
OBJECTIVE: To evaluate protien using enteropathy by Tc-99m dextran scintigraphy. METHODS: Methods for detecting protein loss from the intestine revolve around fecal nitrogen excretion, the clearance of alpha-1 antitrypsin in stools and by endoscopic biopsy. RESULT: The diagnosis of protein-losing enteropathy (PLE) can also be established by a scintigraphic method that is noninvasive, simple and requires no patient preparation or motivation. This diagnostic modality can also delineate the site of protein loss, thereby offering a targeted approach, and if need be, surgery. Radiolabelling of a non-protein, noncolloidal, nonparticulate and biofriendly molecule like dextran with Technetium-99m for imaging enteric protein loss was utilized in imaging eight children with PLE. CONCLUSION: The results were encouraging. The authors advocate the use of this diagnostic tool in identifying patients with PLE, particularly in the pediatric age group.  相似文献   
89.
90.
OBJECTIVE: To evaluate the efficacy of long acting GnRH analogue in improving the auxological outcome of patients with central isosexual precocious puberty (CIPP) and to determine the factors influencing the response. METHODS: Thirty-five patients (30 girls, 5 boys) with CIPP were treated with a long acting GnRH analogue, triptorelin. Final height outcomes and factors affecting treatment were analyzed. RESULTS: Treatment was started at the chronological age (CA) of 6.5 1.8 years in girls and 4.4 1.5 years in boys and continued for a period of 3.7 1.8 years in girls and 6 1.8 years in boys. Follow-up period after discontinuation of treatment was 2.2 0.5 years in girls and 2.6 0.3 years in boys. Treatment led to regression of precocious puberty and reversal of secondary sexual characteristics. There was decline in growth rate reflected by a fall in heightSD of 0.8 0.8 in girls and 2.3 0.9 in boys (p = 0.014), an even greater retardation in bone age (BA) advancement with a decrease in BA-CA of 1.7 1 years in girls and 2.7 1 years in boys and a fall in heightSDBA of 1.5 1.1 in girls and 2.1 1.6 in boys. Final height (149.8 6.9 cm in girls and 161.9 3.9 cm in boys) exceeded projected height at the onset of treatment (143.4 8.3 cm in girls and 154.3 2.7 cm in boys) by 6.4 2.4 cm in girls and 7.6 1.5 cm in boys ( p < 0.001 in both the groups). Factors influencing height gain included age at start of therapy (r = 0.715), BA-CA at the time of initiation of treatment (r = 0.734), heightSDBA at the onset of treatment ( r = 0.566) and the duration of treatment (r = 0.711). Girls treated at an age of less than 6 years (n = 9) had a greater height gain (8.7 1.6 cm versus 5.3 1.9 cm, p < 0.001) and achieved similar final height (148.7 8 cm versus 150.2 6.6 cm) in those treated after this age (n = 21). No side effects of GnRH therapy were observed in the study. CONCLUSION: Long acting GnRH therapy is effective in improving the auxological outcome of patients with CIPP. Maximum benefit is observed in girls with greater bone age advancement treated at a younger age and for a longer duration of treatment. These girls had lower bone age advance at discontinuation of treatment.  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