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31.
中国蒙,汉族酒依赖与醇脱氢酶和醛脱氢酶基因多态性的相关研究 总被引:7,自引:1,他引:6
为探讨醇脱氢酶(ADH)基因和醛脱氢酶(ALDH)基因多态性与酒依赖患病的相互关系,用耳血干血痕聚合酶链反应、等位基因特异性寡核苷酸探针方法,检测乙醇代谢酶ADH和ALDH基因型在我国蒙、汉民族酒依赖与非酒依赖者中分布频率。结果显示在酒依赖组(汉族52例,蒙族31例)与正常对照组(汉族48例,蒙族35例)之间:汉族的ALDH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01),而蒙族则表示为ADH2基因型频率与等位基因频率的分布差异有非常显著性(P<0.01)。这提示汉族酒依赖的发病与ALDH2基因有关,蒙族则与ADH2基因有关。 相似文献
32.
重庆地区驾驶员血液中乙醇浓度与驾驶能力的关系 总被引:5,自引:0,他引:5
目的 探讨重庆地区驾驶员血液中乙醇浓度 (BAC)和驾驶能力的关系 ,为交通安全立法提供科学依据。 方法 随机选择重庆地区 59名驾驶员志愿者 ,建立饮酒后驾车模型、科学的BAC测定以及驾驶能力评价体系 ,对不同BAC下驾驶能力进行测评。 结果 受试者出现驾驶能力损害时的BAC均数为 685.9mg/L ,最小值 190 .0mg/L ,最大值 152 0 .0mg/L ,总体均数 95%可信区间为 60 2 .4~ 70 9.5mg/L。汉族和土家族间、汉族男性和女性间、2 3~ 3 5岁和 3 6~ 56岁年龄组间差异无显著性意义 (P >0 .0 5) ,而既往饮酒量不同的三个组别间差异有显著性意义 (P <0 .0 5)。随着BAC增高 ,驾驶能力受损人数增加。在 2 0 0 .0mg/L有 3 % (2 / 59)的受试者驾驶能力降低 ,80 0 .0mg/L则达到 68% (40 / 59)。 结论 随着BAC增高 ,重庆地区驾驶员驾驶能力受损人数比例增加 ,出现驾驶能力明显损害时BAC为 60 2 .4~ 70 9.5mg/L ,既往酒量较大人群中该值较高 相似文献
33.
Charles J. Meliska Andrzej Bartke Jimmy L. Vandergriff Robert A. Jensen 《Pharmacology, biochemistry, and behavior》1995,50(4):563-570
Transgenic mice overexpressing the phosphoenolpyruvate carboxykinase/bovine growth hormone (PEPCK/ bGH) hybrid gene and normal (nontransgenic) littermate controls (10 males + 10 females/group) were given access to tapwater and an ascending series of concentrations of ethanol (1.0–22.0%), then a similar ascending series of concentrations of nicotine (1.0–40.0 μg/ml), in a two-bottle choice test. Male transgenic mice consumed more and exhibited greater preferences for ethanol and nicotine than control males; transgenic females consumed less and showed lower preferences for ethanol, but not nicotine, than control females. These results suggest that chronic exposure to high levels of bGH may modulate the rewarding effects of ethanol and nicotine in mice in a gender-specific fashion. 相似文献
34.
Beat M. Jucker Maria L. Barnard Robert G. Shulman 《Alcoholism, clinical and experimental research》1994,18(6):1377-1385
Weight gain efficiency differences previously reported between alcohol-fed rats and their controls were investigated. Additionally, the futile cycling of ethanol proposed to explain such differences was studied by NMR spectroscopy. Male Sprague-Dawley rats were fed a nutritionally adequate diet containing 36% of the calories as alcohol, and their paired controls were fed an isocaloric diet for 1 f weeks to establish conditions of chronic alcohol feeding. Normalized metabolic efficiencies varied significantly during the initial 2-week period (6.86 ± 0.51 vs. 2.83 ± 0.18 g/kcal × 10−2 ) for control and alcohol-fed groups, respectively, and to a lesser extent over the entire feeding period (6.41 ± 0.78 vs. 4.60 ± 0.27 g/kcal × 10−2 ) for control and alcohol-fed groups, respectively. Alcohol-induced weight gain inefficiency in metabolism has previously been studied and explained by a variety of different biochemical and physiological mechanisms. One possible pathway of energy wastage may occur due to ethanol futile cycling from ethanol to acetaldehyde through the microsomal ethanol oxidation system pathway, and simultaneously from acetaldehyde to ethanol via the ADH pathway. This futile cycle represents a net loss of 6 ATP/cycle, corresponding to the loss of two reducing equivalents (NADH and NADPH). 1H NMR spectroscopy was used to test for this cycling in blood extracts after administration of 1,1-2 H2 ethanol. No futile cycling was detected either during the initial 2 weeks of feeding or after the entire feeding period. 相似文献
35.
Christina A. Burbeck 《Vision research》1992,32(12):2295-2302
Previous research has shown that separation discrimination thresholds are independent of the internal spatial scale (local spatial frequency) of the targets whose separation is being judged. The experiments reported here tested the generality of this conclusion for separation discrimination of targets that were embedded in an array of identical objects, where crowding could enhance the importance of the scale at which the individual target locations are encoded. No effect of the local spatial scale of the targets was found under these conditions. 相似文献
36.
37.
Introduction The authors report a case of interhemispheric ependymal cyst accompanied with agenesis of the corpus callosum in a fetus.
Discussion Routine ultrasound and subsequent magnetic resonance imaging of a 20-year-old woman at 33 weeks and 1 day of gestation detected
a large interhemispheric cystic lesion in the fetal cranial cavity. Caesarian section was carried out at 36 weeks because
of the progressive enlargement of the fetal head. The cyst was multiloculated and a cyst peritoneal shunt placement resulted
in collapse of the drained cyst components followed by enlargement of others. After wrack-a-mole-like shunt revisions, open
surgery was performed at the age of 2 years. Cyst walls were fenestrated and the cavities were communicated with each other
and eventually with the lateral ventricle. Pathological diagnosis of the cyst wall was ependymal cyst. The boy is now 3 years
old, and growing without apparent developmental delay or recurrence. Current concept and management policy of the interhemispheric
cyst accompanied with agenesis of the corpus callosum is reviewed. 相似文献
38.
Objective:To evaluate the feasibility and safety of prenatal diagnosis by traneabdominal chorionic villus sam-pling(TA-CVS)via the guidance of B-mode ultrasound in the first trimester of gestation.To explore the technique of long time culture and chromosome preparation of villi in early pregnancy.To evaluate the feasibility of the above techniques in the application of the prenatal cytogenetic diagnosis.Methods:One hundred and thirty-five singleton pregnancies at risk were referred from January 2001 to Decem-ber 2007.Results:The average maternal age was 35.2 years.TA-CVS was performed in the 10~13th weeks of gestation and the average gestational age was 10.89 weeks.All attempts at sampling were successful.The rate of operation-associated fetal loss was 0.74%.The failure rate of prenatal diagnosis because of inadequate amount of specimen was 0.The average culture time was 5-7 days.The success rate of the cell culture was 98.5%.No maternal con-temination and bacterial contamination happened.Fifteen cases of abnormal karyotype and one case of confined pla-cantel mosaiciem were diagnosed.Conclusion:TA-CVS appears to be safe and feasible and might to be offered in the prenatal diagnosis in the first trimester of gestation.The technique of long time culture and chromosome preparation of villi is stable and reliable.It is feasible to apply these techniques in the clinical practice of prenatal cytogenetic diagnose in the early pregnancy. 相似文献
39.
Howard B Moss Thomas L Hardie John P Dahl Wade Berrettini Ke Xu 《Neuropsychopharmacology》2007,61(8):974-978
BACKGROUND: Some studies have associated alcohol dependence (AD) with the human serotonin (5-HT)(1B) receptor (HTR1B). This investigation explored the functional responsivity of HTR1B in abstinent AD men using a sumatriptan challenge, while measuring genetic heterogeneity in the HTR1B promoter. METHODS: Abstinent AD men (n = 27) and abstinent men without any alcohol use disorder (n = 19) were administered 6 mg of sumatriptan succinate, subcutaneously. Plasma samples collected over the following 2 hours were assayed for growth hormone (GH) concentrations. His DNA was genotyped for the A-161T and T-261G polymorphisms of the HTR1B promoter and diplotypes determined. RESULTS: Integrated GH responses were predicted by interactions of AD and promoter diplotypes, as well as subject ethnicity. The final model accounted for nearly 35% of the variance in GH responses. Post hoc evaluation revealed that AD was associated with a blunting of GH secretion only among individuals with the most common HTR1B diplotype (TT/TT). CONCLUSIONS: A blunting of GH responses in abstinent AD men was observed only among those with the most common HTR1B promoter diplotype. Less common promoter diplotypes appeared protective. Controlling for genetic background is a useful augmentation of case-control pharmacological challenge strategies designed to elucidate the psychobiology of AD and other complex disorders. 相似文献
40.
Amos Zeichner Peter R. Giancola Joseph D. Allen 《Alcoholism, clinical and experimental research》1995,19(4):977-983
The purpose of this study was to compare the stress-response-dampening (SRD) effect of alcohol in hostile and nonhostile men based on a combined score of four subscales of the Cook-Medley Hostility Scale . Subjects were 72 male social drinkers. Subjects' cardiac interbeat-interval, and systolic and diastolic blood pressure reactivity to a situational stressor were measured following the consumption of either alcohol, no alcohol, or an active placebo beverage. Results demonstrated that hostile men evinced lower heart rate and systolic blood pressure (SBP) reactivity to the stressor when given alcohol, compared with intoxicated nonhostile subjects, and lower reactivity relative to all other groups, with the exception of SBP in the nonhostile controls. These results allow for speculation that hostile men may be more likely than controls to experience possible SRD effects of alcohol and thus, perhaps, be predisposed to increased alcohol consumption when under stress. 相似文献