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21.
J. F. Knight 《Pediatric nephrology (Berlin, Germany)》1990,4(5):533-541
Laboratory studies of the pathophysiology of Henoch-Schönlein purpura (HSP) have become more numerous in recent years with the recognition of the disease's links with the mucosal immune system in general and IgA nephropathy in particular. There are weak genetic associations with C4 null phenotypes and with HLA B35 and DR4. Studies of plasma proteins in HSP patients show an increased IgA concentration, activation of the alternative pathway of complement and consumption of factor XIII. High molecular weight (polymeric) IgA has been detected in affected individuals, which some investigators have called immune complexes. Many patients synthesise an IgA rheumatoid factor in the acute phase, but other autoantibodies are largely absent. In vitro studies of lymphocytes from HSP patients have demonstrated an increased number of IgA-bearing and secreting B-cells, with altered T-cell regulation of antibody synthesis. While these observations point to immune dysregulation — primarily of IgA production — as a consistent feature of acute HSP, there is as yet insufficient information available to allow a consistent theory of pathogenesis to be formulated. 相似文献
22.
23.
Charcot—Marie—Tooth病的遗传,临床和电生理观察(附20例临床分析) 总被引:6,自引:0,他引:6
本文报道 20例 Charcot-Marie-Tooth病的遗传、临床和电生理资料。其中男 16例,女 4例,平均发病年龄为26.75岁。发现4例显性遗传,3例隐性遗传,10例散发,3例遗传情况不详。主要症状有高弓足、垂足、鹤腿和腱反射消失;上肢前臂有肌萎缩者占1/4。所有病人电生理检查均有失神经现象,特别是MCV有明显减慢。且发现MCV的减慢和临床严重程度无相关联系。 相似文献
24.
25.
The inheritance of focal dystonias was investigated in 43 families containing 43 index cases with torticollis (n = 21), blepharospasm (n = 18) and writer's cramp (n = 4). They generated a potential population of 235 first-degree relatives, and 168 out of 179 living first-degree relatives were examined. Ten relatives with dystonia were identified in ten families. Another two parents from two of the same group of ten families were affected according to the family history. The majority of the secondary cases (six patients, five siblings, and one child) were not aware of any dystonia. The tendency for affected relatives to have the same type of dystonia as index patients was observed only for torticollis. Overall, 23% of index patients had relatives with dystonia. Segregation analysis suggested the presence of an autosomal dominant gene or genes with reduced penetrante underlying focal dystonia. 相似文献
26.
谷子种子经高空气球搭载后的遗传变异研究 总被引:11,自引:2,他引:9
目的 选育出高产、蛋白质和用脂肪含量高的谷子品(系)种。方法 利用高空气球搭载谷子的干种子,在高空飘游8h后回收种植,对其植物学特性及进行分析研究。结果 种子发芽率比对照低5.2%,发芽热比对照高21.1%。SP1代植株高度比对照低6.8cm,旗叶面积比对照高25%,穗重比对照高15.9%;SP3代大穗型株系性状相对稳定,其中SP3-2的种子蛋白质和脂肪含量均高于对照经高空气球搭载后的SPE-35 相似文献
27.
Most affected (MA) and least affected (LA) rats, bred for extremes in motor impairment following an alcohol challenge, differed in their performance on two active avoidance tasks. In two-way shuttle avoidance, the MA line performed significantly better than the LA group, both in terms of response latencies and percent avoidances. The inferior performance of the LA line persisted across the 15 days of testing, and appeared to reflect an difference in asymptotic performance levels. In one-way avoidance, the MA line showed significantly better acquisition than the LA group; however, this difference dissipated across the 3 days of training. When tested following alcohol administration in either the one-or two-way avoidance paradigm, the MA rats showed a greater performance deficit than LA animals. These data were interpreted as indicating the generality of alcoholrelated line differences to a situation motivated by aversive consequences. Moreover, the line difference in avoidance acquisition represents one of the few non-drug-related phenotypic differences that have been found in these lines. In previous generations, disparate base rates of wheel running have been reported, and the data presented here confirm and extend this finding. 相似文献
28.
Two lines of rats, least affected (LA) and most affected (MA), had been selectively bred for their differential sensitivity to ethanol. Both males and females of the LA strain were observed to be less sensitive than their MA counterparts to the acute hypnotic and motor-impairing effects of ethanol. However, a lower ethanol metabolic rate of the MA males suggests that both CNS and metabolic factors contribute to their enhanced sensitivity to ethanol. By contrast, no differences were observed between the LA and MA males with respect to the hypnotic and subhypnotic effects of pentobarbital or to the clearance of this drug. MA females were more sensitive only to the hypnotic effects of pentobarbital, probably because of a smaller apparent volume of distribution. No strain difference was observed in the hypnotic effect or clearance of barbital. These observations suggest that, in spite of a differential sensitivity to ethanol, the LA and MA lines do not differ in their response to the barbiturates tested. 相似文献
29.
Central nervous system hemangioblastomas, endolymphatic sac tumors, and von Hippel-Lindau disease 总被引:4,自引:0,他引:4
Von Hippel-Lindau disease (VHL) is a hereditary cancer syndrome caused by germline mutations of the VHL tumor suppressor gene.
Major progress has been made in the last decade in both clinical and fundamental aspects of VHL. The VHL gene product, pVHL,
has major and multiple functions: pVHL regulates not only first angiogenesis but also extracellular matrix formation and the
cell cycle. A molecular diagnosis of VHL is now available, leading to a transformation in clinical management of patients
and their families. Diagnosis of VHL has to be suspected in patients with a VHL-related tumor without familial history and
especially in case of hemangioblastoma or endolymphatic sac tumors. Such patients should be systematically investigated for
clinical and molecular evidence of VHL disease. Treatment of symptomatic hemangioblastomas remains mainly neurosurgical, often
in emergency, but stereotactic radiosurgery is emerging as an alternative therapeutic procedure. In the future, antiangiogenic
drugs could represent a potential medical treatment of CNS hemangioblastomas in view of their highly vascular structure. Lastly,
visceral manifestations of VHL disease are also of critical importance and require early detection for effective treatment.
Received: 22 January 2000 / Accepted: 21 February 2000 相似文献
30.
Gene mapping of SEZ group genes and determination of pentylenetetrazol susceptible quantitative trait loci in the mouse chromosome 总被引:1,自引:0,他引:1
Wakana S Sugaya E Naramoto F Yokote N Maruyama C Jin W Ohguchi H Tsuda T Sugaya A Kajiwara K 《Brain research》2000,857(1-2):286-290
Gene mapping of the newly discovered SEZ genes (seizure-related genes) in the mouse was performed by linkage analysis. SEZ6 was on chromosome 11, SEZ12 on chromosome 16, SEZ15 on chromosome 3 and SEZ17 (PTZ17) on chromosome 18. The mouse chromosomal locus related to high susceptibility to pentylenetetrazol (PTZ) was also determined by linkage analysis using the recombinant inbred mouse, BXD (C57BLxDBA). A significant level of PTZ susceptibility was found on chromosome 2. Chromosomal loci of the newly discovered SEZ genes were not coincident with the significant chromosomal loci to PTZ susceptibility. Since epilepsy is assumed to be a disease syndrome which is probably manifested by abnormal expression of multifocal genes, determination of the role of each chromosomal locus in the provocation of seizure activity is important. 相似文献