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21.
The Recuperative Effects of REM Sleep and Stage 4 Sleep on Human Performance After Complete Sleep Loss: Experiment 1 总被引:4,自引:0,他引:4
Twelve young (17–21 yrs) male Navy recruits volunteered for a sleep loss study. After 4 baseline days, the Ss were completely deprived of sleep for 2 days and nights. Next followed an experimental phase of 2 days and nights after which all Ss received 2 nights of uninterrupted sleep. During the experimental phase, the 4 Ss in the REM-deprived group were aroused whenever they showed signs of REM sleep. The 4 Ss of the stage 4-deprived group were aroused whenever they showed signs of entering stage 4 sleep, and the 4 Ss of the Control group had uninterrupted sleep. All tests (speed and accuracy of addition, speed and accuracy of self-paced vigilance, errors of omission in experimenter paced vigilance, immediate recall of word lists, and mood) showed significant impairment after the first night of complete sleep loss. But during the experimental (sleep-stage-deprivation) and recovery phases, all three groups showed equal rates of recovery. Depriving the S of stage REM or stage 4 during recovery sleep does not affect the recuperation rate. Frequent arousals (50–100 per night) also do not impair recovery. The amount of sleep is probably more important than the kind of sleep. 相似文献
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Epithelial cells (EC) from various tissues can produce important cytokines and chemokines when stimulated by proinflammatory cytokines. These EC also receive signals from cell surface integrins, like the alpha3beta1 integrin, which is important in cell migration and wound healing of epithelial monolayers. However, little is known of the effect of integrin signals on cytokine responses by EC. Colonic Caco-2 cells treated with an anti-alpha3 integrin antibody prior to stimulation with the proinflammatory cytokine interleukin (IL)-1 yielded suppressed levels of mRNA and secreted IL-6, IL-8 and monocyte chemoattractant protein-1 as compared to cells treated with normal mouse immunoglobulin G. Lung A549 cells also showed a similar suppression of cytokine secretion. Likewise, treatment of the Caco-2 cells with the same antibody suppressed tumour necrosis factor-alpha-stimulated IL-6 secretion. Fab fragments of the anti-alpha3 integrin antibody did not induce the suppressive effect but did block the suppressive effect of the whole antibody suggesting that the effect of the antibody required cross-linking of the integrins. Finally, culture of the Caco-2 cells on laminin type 5 (the major ligand for this integrin) yielded depressed levels of IL-1-induced IL-6 secretion as compared to cells on laminin type 1. These data are the first indication that the alpha3beta1 integrin may cause a suppression of cytokine responses by EC which may be important in regulating the capacity of EC to respond during inflammation or wound healing. 相似文献
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Mutational analysis of the SOX9 gene in campomelic dysplasia and autosomal sex reversal: lack of genotype/phenotype correlations 总被引:9,自引:1,他引:9
Meyer J; Sudbeck P; Held M; Wagner T; Schmitz ML; Bricarelli FD; Eggermont E; Friedrich U; Haas OA; Kobelt A; Leroy JG; Van Maldergem L; Michel E; Mitulla B; Pfeiffer RA; Schinzel A; Schmidt H; Scherer G 《Human molecular genetics》1997,6(1):91-98
It has previously been shown that, in the heterozygous state, mutations in
the SOX9 gene cause campomelic dysplasia (CD) and the often associated
autosomal XY sex reversal. In 12 CD patients, 10 novel mutations and one
recurrent mutation were characterized in one SOX9 allele each, and in one
case, no mutation was found. Four missense mutations are all located within
the high mobility group (HMG) domain. They either reduce or abolish the
DNA-binding ability of the mutant SOX9 proteins. Among the five nonsense
and three frameshift mutations identified, two leave the C-terminal
transactivation (TA) domain encompassing residues 402-509 of SOX9 partly or
almost completely intact. When tested in cell transfection experiments, the
recurrent nonsense mutation Y440X, found in two patients who survived for
four and more than 9 years, respectively, exhibits some residual
transactivation ability. In contrast, a frameshift mutation extending the
protein by 70 residues at codon 507, found in a patient who died shortly
after birth, showed no transactivation. This is apparently due to
instability of the mutant SOX9 protein as demonstrated by Western blotting.
Amino acid substitutions and nonsense mutations are found in patients with
and without XY sex reversal, indicating that sex reversal in CD is subject
to variable penetrance. Finally, none of 18 female patients with XY gonadal
dysgenesis (Swyer syndrome) showed an altered SOX9 banding pattern in SSCP
assays, providing evidence that SOX9 mutations do not usually result in XY
sex reversal without skeletal malformations.
相似文献
27.
Bellcross CA Bedrosian SR Daniels E Duquette D Hampel H Jasperson K Joseph DA Kaye C Lubin I Meyer LJ Reyes M Scheuner MT Schully SD Senter L Stewart SL St Pierre J Westman J Wise P Yang VW Khoury MJ 《Genetics in medicine》2012,14(1):152-162
Lynch syndrome is the most common cause of inherited colorectal cancer, accounting for approximately 3% of all colorectal cancer cases in the United States. In 2009, an evidence-based review process conducted by the independent Evaluation of Genomic Applications in Practice and Prevention Working Group resulted in a recommendation to offer genetic testing for Lynch syndrome to all individuals with newly diagnosed colorectal cancer, with the intent of reducing morbidity and mortality in family members. To explore issues surrounding implementation of this recommendation, the Centers for Disease Control and Prevention convened a multidisciplinary working group meeting in September 2010. This article reviews background information regarding screening for Lynch syndrome and summarizes existing clinical paradigms, potential implementation strategies, and conclusions which emerged from the meeting. It was recognized that widespread implementation will present substantial challenges, and additional data from pilot studies will be needed. However, evidence of feasibility and population health benefits and the advantages of considering a public health approach were acknowledged. Lynch syndrome can potentially serve as a model to facilitate the development and implementation of population-level programs for evidence-based genomic medicine applications involving follow-up testing of at-risk relatives. Such endeavors will require multilevel and multidisciplinary approaches building on collaborative public health and clinical partnerships. 相似文献
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29.
Overstreet DH Moy SS Lubin DA Gause LR Lieberman JA Johns JM 《Physiology & behavior》2000,70(1-2):149-156
The present studies sought to determine whether prenatal cocaine administration (15 mg/kg b.i.d. between gestational ages 1-20) had enduring effects on emotional behavior of rats. Rats prenatally treated with cocaine interacted less with other rats in the social interaction test of anxiety at both 30 and 120 days of age. However, there were no differences in the elevated plus maze test of anxiety. Rats prenatally treated with cocaine were significantly more immobile in the forced-swim test at 60 and 120 days of age. In addition, animals exposed to prenatal cocaine were more sensitive to the enhancing effect of phencyclidine (2.0 mg/kg) on startle responses to an acoustic stimulus. The cocaine-treated animals tested at 50 to 60 days of age showed higher levels of prepulse inhibition, in comparison to the saline group, after vehicle pretreatment, but not after phencyclidine. Although there were gender differences in the expression of some of these behavioral tasks, there were no gender differences in the effects of cocaine. These findings indicate that when emotional behavior is altered by prenatal cocaine administration, the effects are enduring. 相似文献
30.
目的 了解DNA指数 (DI)与人肝细胞系生物功能之间的关系。探讨DI值可否作为人工肝生物材料的初步筛选指标。方法 收集国内 9株人工肝细胞系 ,分别编号为细胞系 1- 9(CL1-9)。分别培养后获取细胞。取正常人全血分离淋巴细胞 ,作为正常二倍体对照。以流式细胞仪(FCM)测定 9株人肝细胞系DI值作为分化指标 ,判断人肝细胞系的分化情况。人肝细胞系分别接种1.2× 10 6个细胞 ,收集其培养生长旺盛、生物功能良好的第 5天时的培养上清液 ,测定上清液中的尿素、人白蛋白和安定含量 ,计算细胞系尿素合成、人白蛋白合成和安定转化量。进行DI值和肝功能指标间的相关性分析。CX7自动生化分析仪测定尿素浓度 ;用人白蛋白放免试剂盒经改良后采用放射免疫抗原竞争法测定人白蛋白浓度 (人白蛋白与牛血清白蛋白无交叉反应 ) ;培养上清中另加入 4 μg/ml安定作肝细胞药物代谢功能指标 ,提取后以 75 2型紫外分光光度计测定安定含量。采用双变量相关与回归分析方法进行统计学分析。结果 人肝细胞系DI值与人肝细胞系尿素合成量、人白蛋白合成量及安定转化量均呈线性相关 ,相关系数分别为 - 0 .94 37、- 0 .8795、- 0 .9386。结论 CL1分化程度最高 ,生物功能最好 ;DI值可以作为人工肝生物材料的初步筛选指标 相似文献