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   789篇
  免费   32篇
  国内免费   3篇
耳鼻咽喉   3篇
儿科学   36篇
妇产科学   11篇
基础医学   54篇
口腔科学   15篇
临床医学   103篇
内科学   180篇
皮肤病学   10篇
神经病学   20篇
特种医学   248篇
外科学   32篇
综合类   16篇
预防医学   29篇
眼科学   4篇
药学   32篇
  1篇
中国医学   8篇
肿瘤学   22篇
  2021年   3篇
  2020年   2篇
  2018年   4篇
  2017年   5篇
  2016年   7篇
  2015年   12篇
  2014年   7篇
  2013年   13篇
  2012年   9篇
  2011年   23篇
  2010年   28篇
  2009年   26篇
  2008年   16篇
  2007年   20篇
  2006年   19篇
  2005年   17篇
  2004年   7篇
  2003年   10篇
  2002年   13篇
  2001年   7篇
  2000年   6篇
  1999年   8篇
  1998年   38篇
  1997年   35篇
  1996年   35篇
  1995年   46篇
  1994年   37篇
  1993年   37篇
  1992年   7篇
  1991年   3篇
  1990年   11篇
  1989年   37篇
  1988年   23篇
  1987年   29篇
  1986年   37篇
  1985年   21篇
  1984年   17篇
  1983年   14篇
  1982年   15篇
  1981年   19篇
  1980年   18篇
  1979年   9篇
  1978年   15篇
  1977年   15篇
  1976年   13篇
  1975年   12篇
  1959年   2篇
  1958年   4篇
  1957年   6篇
  1954年   2篇
排序方式: 共有824条查询结果,搜索用时 15 毫秒
1.
Neuropsychological outcomes in children of mothers with epilepsy.   总被引:1,自引:0,他引:1  
The study investigated the nature of the effects of maternal epilepsy on cognitive performance of the offspring. One hundred fifty-four children of mothers with epilepsy aged 5 to 11 years (study group), along with 130 control children, comparable with respect to IQ, socio-economic status, age, and gender underwent a neuropsychological assessment using subtests from the NEPSY: A Developmental Neuropsychological Assessment, tapping attentional, auditory-verbal, visuomotor, fine motor, and memory abilities. The study group scored significantly lower than the controls on measures of attention, memory, and fine-motor function. Deficits were more marked in but not limited to the subset of the study group exposed to maternal medication in utero. Group differences on auditory attention were found only in younger children. Valproate-exposed children obtained lower scores on sentence repetition, as well as on the more demanding part of a test of auditory attention, than other children in the study group, suggesting weaknesses in working memory in the former subgroup. Confounding by maternal epilepsy type and polytherapy complicate interpretation of this finding. Differences between subsets of children not exposed to anti-epileptic drugs in utero and controls suggest that both drug exposure and genetic factors may contribute to cognitive deficits associated with maternal epilepsy.  相似文献   
2.
The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
3.
Rigor and resistance to stretch in vertebrate smooth muscle   总被引:2,自引:0,他引:2  
  相似文献   
4.
Davis  GD; Fulton  RE; Ritter  DG; Mair  DD; McGoon  DC 《Radiology》1978,128(1):133-144
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries.  相似文献   
5.
KA Daly  RE Selvius  B Lindgren 《Pediatrics》1997,100(6):931-936
OBJECTIVES: To investigate maternal knowledge and attitudes about otitis media (OM) risk, to estimate the prevalence of risk factors in the first year of life, and to identify barriers to the reduction of risk factors (eg, formula feeding, day care attendance, and exposure to passive smoke). METHODS: Questionnaires mailed to a systematic sample of 504 Minnesota women >/=18 years old identified through 1994 birth certificates. RESULTS: Eighty percent returned a completed survey. According to maternal report, 29% of infants (age 8 to 13 months) had recurrent OM (>/=3 episodes) and 2% had tympanostomy tubes. Forty-six percent attended day care, 29% had >/=1 smoking parent, and 49% breastfed for 相似文献   
6.
We previously reported that papillomas can arise from the follicular epithelium of v-Ha-ras transgenic TGxAC mice. Since the viable-yellow mutation (A(vy)) of the mouse agouti gene which regulates coat color pigmentation by acting within the micro-environment of the hair follicle has been shown to function as a tumor promoter in the liver, we hypothesized that it may also play a role in TGxAC skin tumorigenesis. Endogenous agouti protein product was detected in the outer root sheath of anagen hair follicles following plucking of the hair shaft, but not in the interfollicular epithelium, in TGxAC mice on an FVB/N genetic background. It was also detected in papillomas from these mice produced by 12-O-tetradecanoylphorbol-13-acetate (TPA) treatment or plucking. Expression of the A(vy) allele in the v-Ha-ras transgenic TGxAC mouse line results in an approximately 2-fold increase in papilloma development compared with controls which did not carry the A(vy) allele following twice-weekly treatment with 1.25, 2.5 or 5.0 microg TPA. In addition, TPA-treated, papilloma-bearing F1 mice which carried the A(vy) allele, but not F1 mice which did not carry the A(vy) allele, exhibited a syndrome of humoral hypercalcemia mediated by parathyroid hormone-related protein (PTHrP) that led to weight loss, hypercalcemia and hypophosphatemia. Thus, we conclude that the A(vy) allele can influence the development of skin tumors and PTHrP-mediated humoral hypercalcemia in v-Ha-ras transgenic TGxAC mice.   相似文献   
7.
8.
Two children are reported in whom intestinal pseudo-obstruction was the initial manifestation of systemic sclerosis. Gastrointestinal symptoms and skin changes resolved or improved in both children following treatment with prednisone and penicillamine (case 1) or methotrexate (case 2), although radiological changes of the gastrointestinal tract persisted at 3 and 2 yr of follow-up, respectively.   相似文献   
9.

Background:

Monoamine reuptake inhibitors exhibit unique clinical profiles that reflect distinct engagement of the central nervous system (CNS) transporters.

Methods:

We used a translational strategy, including rodent pharmacokinetic/pharmacodynamic modeling and positron emission tomography (PET) imaging in humans, to establish the transporter profile of TD-9855, a novel norepinephrine and serotonin reuptake inhibitor.

Results:

TD-9855 was a potent inhibitor of norepinephrine (NE) and serotonin 5-HT uptake in vitro with an inhibitory selectivity of 4- to 10-fold for NE at human and rat transporters. TD-9855 engaged norepinephrine transporters (NET) and serotonin transporters (SERT) in rat spinal cord, with a plasma EC50 of 11.7ng/mL and 50.8ng/mL, respectively, consistent with modest selectivity for NET in vivo.Accounting for species differences in protein binding, the projected human NET and SERT plasma EC50 values were 5.5ng/mL and 23.9ng/mL, respectively. A single-dose, open-label PET study (4–20mg TD-9855, oral) was conducted in eight healthy males using the radiotracers [11C]-3-amino-4- [2-[(di(methyl)amino)methyl]phenyl]sulfanylbenzonitrile for SERT and [11C]-(S,S)-methylreboxetine for NET. The long pharmacokinetic half-life (30–40h) of TD-9855 allowed for sequential assessment of SERT and NET occupancy in the same subject. The plasma EC50 for NET was estimated to be 1.21ng/mL, and at doses of greater than 4mg the projected steady-state NET occupancy is high (>75%). After a single oral dose of 20mg, SERT occupancy was 25 (±8)% at a plasma level of 6.35ng/mL.

Conclusions:

These data establish the CNS penetration and transporter profile of TD-9855 and inform the selection of potential doses for future clinical evaluation.  相似文献   
10.
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