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71.
恒力法测量运动对动物肌腱,韧带横截面积的影响 总被引:2,自引:0,他引:2
刘波 《生物医学工程学杂志》1993,10(4):349-352
本文介绍一种方便,适用的肌腱,韧带横截面积的测量工具-软组织横截面积测微计。通过对兔屈趾肌腱反复测量,其重复性精密度在0.044mm以内,变异系数在1.4%以下,用该测微计对大强度训练一段时间后的兔屈趾肌腱,跟腱和膝内侧副韧带的测量发现,训练训练后FDP,AC的横截面积减小,MCL有增大的趋势,据此,作用认为肌腱的变化与长期大强度训练后试件的“疲劳蠕变”有关,MCL的变化则与在体内的负荷形式有关。 相似文献
72.
五种免疫相关性心血管疾病的免疫学研究 总被引:4,自引:0,他引:4
对扩张型心肌病、风湿性心脏病,原发性高血压,冠心病及肥厚型心肌病进行外周血清可溶性白细胞介素2受体,T淋巴细胞亚群及自然杀伤细胞活性的检测,并与健康对照组比较,结果显示:DCM组,RHD组及EHT组的sIL-2R明显高于NC组,而DCM、RHD风湿活动组的NK活性低于NC组,EHT组NK活性高于NC组。 相似文献
73.
有关HIV感染引起CD4’T淋巴细胞耗竭最终导致艾滋病的确切机制尚不清楚。目前研究最多的仍是细胞凋亡理论,本文就细胞凋亡在艾滋病发病中的作用,凋亡的可能机制两方面进行概述。 相似文献
74.
目的 应用多普勒组织显像评价高血压病心房内传导间期变化与房性心律失常的关系 ;方法 利用超声多普勒组织显像法测量了 2 0例高血压病心房内传导间期与正常人对比分析 ;结果 高血压病心房内传导间期存在异常 ,心房内传导间期与左房内径大小无相关 (r =0 1,P >0 2 5 ) ,与左室舒张功能指标E A比值中度相关 (r=0 5 7,0 0 1
0 2 5 ) ;结论 高血压病房性心律失常与心房内传导异常及左室舒张功能有关 ,多普勒组织显像法是一种较好的测量高血压病心房内传导间期的方法 相似文献
75.
76.
Evaluation of collateral sprouting after end-to-side nerve coaptation using a fluorescent double-labeling technique. 总被引:8,自引:0,他引:8
The mechanism of end-to-side neurorrhaphy is believed to be by collateral sprouting, although evidence for this is lacking. This study validates whether axonal sprouting originates from the donor intact nerve by collateral sprouting with the use of a fluorescent double-labeling technique. End-to-side neurorrhaphy was performed on adult female Sprague-Dawley rats. Eight and 12 months postoperatively, animals were injected with true blue and diamidino yellow into the tibialis anterior and/or gastrocnemius muscles and were transcardially perfused with fixative after 7 days of retrograde transport. The lumbar enlargement and the dorsal root ganglia from L3 to L6 were harvested and serial sectioning and fluorescent microscopy were performed. No double-labeling neurons were observed in control animals, but a group of neurons that were greenish or yellowish in color were seen with single labeling. Double-labeling neurons, however, were seen in animals treated with end-to-side neurorrhaphy whether or not perineurotomy was performed. These results demonstrate that one parent nerve fiber can emanate another axon by collateral sprouting following end-to-side neurorrhaphy. We hypothesize that the causes of collateral sprouting might result from "switching signals" and/or "switching factors." Copyright 1999 Wiley-Liss, Inc. 相似文献
77.
Jan Lycke Bo Svennerholm Elisabeth Hjelmquist Lars Frisén Gaby Badr Mats Andersson Anders Vahlne Oluf Andersen 《Journal of neurology》1996,243(3):214-224
Acyclovir treatment was used in a randomized, double-blind, placebo-controlled clinical trial with parallel groups to test the hypothesis that herpes virus infections are involved in the pathogenesis of multiple sclerosis (MS). Sixty patients with the relapsing-remitting form of MS were randomized to either oral treatment with 800 mg acyclovir or placebo tablets three times daily for 2 years. The clinical effect was investigated by an extensive test battery consisting of neurological examinations, neuro-ophthalmological and neuropsychological tests, and evoked potentials. Results were based on intent-to-treat data and the primary outcome measure was the exacerbation rate. In the acyclovir group (n = 30), 62 exacerbations were recorded during the treatment period, yielding an annual exacerbation rate of 1.03. The placebo group (n = 30) had 94 exacerbations and an annual exacerbation rate of 1.57. Thus, 34% fewer exacerbations were encountered during acyclovir treatment. This difference in exacerbation rate between the treatment groups was not significant (P = 0.083). However, this trend to a lower disease activity in acyclovir-treated patients was supported in subsequent data analysis. If the patients were grouped according to exacerbation frequencies, i.e. into low (0–2), medium (3–5) and high (6–8) rate groups, the difference between acyclovir and placebo treatment was significant (P = 0.017). Moreover, in a subgroup of the population with a duration of the disease of at least 2 years providing an exacerbation rate base-line before entry, individual differences in exacerbation rates were compared between the 2-year pre-study period and the study period in acyclovir-treated (n = 19) and placebo (n = 20) patients and acyclovir-treated patients showed a significant reduction of exacerbations (P = 0.024). Otherwise, neurological parameters were essentially unaffected by acyclovir treatment and there were no convincing signs of reduced neurological deterioration in the acyclovir group. This study indicates that acyclovir treatment might inhibit the triggering of MS exacerbations and thus suggests that acyclovir-susceptible viruses might be involved in the pathogenesis of MS. This possibility warrants further investigation. 相似文献
78.
79.
The objective of the present study was to assess the relationship between the amount of lactate accumulated during complete ischaemia and the ensuing changes in extra- and intracellular pH (pHe and pHi, respectively). The preischaemic plasma glucose concentration of anaesthetized rats was varied by administration of glucose or insulin, pHe was determined in neocortex with ion-sensitive microelectrodes, and tissue lactate and CO2 contents were measured, tissue CO2 tension being known from separate experiments. The experiments were carried out in both normocapnic [arterial CO2 tension (PaCO2) approximately 40 mm Hg] and hypercapnic (PaCO2 approximately 80 mm Hg) animals. Irrespective of the preischaemic CO2 tension, DeltapHe was linearly related to tissue lactate content. Depending on the preischaemic glucose concentration, DeltapHe varied from <0.4 to >1.4 units. The results thus fail to confirm previous results that the changes in pHe describe two plateau functions (DeltapHe approximately 0.5 and 1.1, respectively), with a transition zone at tissue lactate contents of 17 - 20 mmol kg-1. Changes in pHi given in this study are based on the assumption of a uniform intracellular space. The pHi changed from a normal value of approximately 7.0 to 6.5, 6.1 and 5.8 at tissue lactate contents of 10, 20 and 30 mmol kg-1. The intrinsic (non-bicarbonate) buffer capacity, derived from these figures, was 23 mmol kg-1 pH-1. Some differences in pH and in HCO3- concentration between extra- and intracellular fluids persisted in the ischaemic tissue. These differences were probably caused by a persisting membrane potential in the ischaemic cells. 相似文献
80.
V V Bo?ko D E Nemirovski? V V Turygin 《Sovetskoe zdravookhranenie / Ministerstvo zdravookhranenii?a SSSR》1991,(7):43-47
Using special survey questionnaires industrial problems were identified which directly or indirectly determine healthy lifestyle of workers at the Leningrad spinning factory "Red Thread". Difficulties, efforts and potential opportunities to solve these problems were determined with the assistance of administration and public, and also the reasons for ++shrinking of different authorities from the solution of some problems. The apparent divergences in the assessment of problems by different authorities and the necessary attribution of responsibility for their solution require special instructions for the practice of healthy lifestyle formation. 相似文献