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1.
通过对中医古籍中有关升降散论述的文献梳理,全面探讨其内涵。本方是在大黄、僵蚕为雏形的基础上增加蝉蜕、姜黄而成方,几经易名,终在杨璿《伤寒瘟疫条辨》中为后人所熟知。本方广泛用于治疗瘟疫,以丸剂、散剂为主,方便携带,便于服用;重用大黄旨在祛邪、逐秽;应用时视人之体质强弱和量其毒之轻重而判断用药多寡,并辅以米酒、生蜜等以顾护正气。杨璿将其由治疗“热疫”的专方扩展为治疗“表里三焦大热”的通用方剂,扩大了本方治疗疾病范围。  相似文献   
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为了提高立体定向扣带束毁损术的疗效,本文对30例(60侧)成人正常脑标本探索在大脑原点前、扣带束毁损术最佳靶点的位置、坐标值及其毗邻关系。研究结果认为最佳手术部位应选择在原点前12mm处,该束高度为4.40±4.20mm、宽度为6.60±3.06mm、中心点距x轴的坐标值为6.30±2.20mm、该处扣带束的最低点与侧脑室前角的最高点间的距离为4.00±3.40mm,供临床参考。  相似文献   
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Intracellular recordings were obtained from identified dopamine (DA) neurons in rat midbrain slices maintained in vitro. DA neuron membranes exhibited pronounced instantaneous and time-dependent anomalous rectification that showed evidence of maximal activation at average membrane potentials of -63 and -78 mV, respectively. Action potentials were followed by prominent afterhyperpolarizations (AHP) that consisted of two components. The fast component showed evidence of inactivation at -63 mV independent of the initial membrane potential, whereas the longer-duration, later component increased in amplitude at hyperpolarized potentials. Unlike DA neurons recorded in vivo, there was no evidence of spike frequency adaptation or summation of AHPs with prolonged depolarization-induced spike trains. Spontaneous spike discharge occurred via an endogenous pacemaker potential that was dependent on both TTX-sensitive and cobalt-sensitive processes. Hyperpolarizing prepulses could activate rebound pacemaker discharge, but this rebound activity was progressively blocked with larger-amplitude hyperpolarizing prepulses. DA neurons recorded in the anesthetized animal, freely moving animal, and in vitro preparations have been shown to exist in two states of activity: 1) spontaneously discharging action potentials or 2) hyperpolarized, quiescent, and nonfiring. Furthermore, although it is rare to find DA neurons in the untreated animal in transitional states of activity, quiescent neurons can be activated by stimuli that place a demand on the DA system. The evidence presented here is consistent with the hypothesis that the special combination of membrane properties of DA neurons contribute to the segregation of their activity into active or inactive states.  相似文献   
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Summary Allotransplantation of solid organs transfers passenger leucocytes which may give rise to a state of persistent microchimaerism. In this report we describe the case of a patient who developed a solitary plasmacytoma in a transplanted kidney more than 10 years after allografting. The diagnosis was established on the basis of the presence of a monoclonal IgG kappa peak in the serum, and light chain proteinuria, the plasmacytoid features of tumour cells including cell surface expression of IgG, kappa light chains, CD20, CD38 and CD56, the absence of lytic bone lesions and a normal bone marrow biopsy, and the disappearance of the monoclonal IgG peak after graft nephrectomy. A donor origin of the tumour was established by HLA DNA typing of tumour, tumour-free kidney tissue, and peripheral blood leucocytes, respectively.  相似文献   
6.
Whole-cell patch-clamp recordings (WCR) were made from sympathetic preganglionic neurons (SPN) in neonate rat spinal cord slices. SPN were identified histologically by filling them with the fluorescent dye Lucifer Yellow contained within the patch pipette solution. Current clamp recordings were obtained from SPN with a potassium based pipette solution. The cells exhibited many of the characteristic properties of SPN seen previously with intracellular recordings in both the rat and the cat. However, we found an order of magnitude increase in both cell input resistance (950 MΩ) and time constant (118 ms) over those seen with conventional recordings. We believe these values approximate better the situation in intact cells, and will have a vital bearing upon how SPN integrate inputs. We conclude that WCR in spinal cord slices provides a powerful tool for investigating the cellular properties of SPN.  相似文献   
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Until recently, most reported cases of bacteraemia caused by multidrug-resistant strains of Enterobacteriacae producing an extended-spectrum beta-lactamase (ESBL) in Europe have been nosocomial in origin. However, increasing numbers of reports of community-acquired bacteraemia and urinary tract infection caused by ESBL-producing microorganisms suggest that the geographical origin of patients should be taken into account as a risk-factor for possible ESBL production. Early identification of patients at high-risk of infection with ESBL-producing microorganisms, based on their geographical origin and travel history, should help to optimise initial antibiotic treatment strategies for severe urinary tract infections in Europe.  相似文献   
8.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae.  相似文献   
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Trisomy 18 is the second most common genetic defect after trisomy 21, almost 90% of which are due to additional chromosome from the mother. The parental origin of the additional chromosome can, if required, be determined by two methods: karyotyping, which takes several weeks; or, more recently, by polymerase chain reaction (PCR) which is often problematic. Fluorescent PCR of small tandem repeats (STRs) can determine the parental origin in the majority of cases within 5 h. Although the incidence of paternal origin is known for both trisomy 21 and trisomy 18, this technique can rapidly determine the parental origin in cases where there is insufficient samples to perform conventional tests. Determining parental origin by these methods may also have clinical significance in the diagnosis of chromosomal translocations or in the diagnosis of genetic disease using linkage analysis.  相似文献   
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BACKGROUND: Two genome scans for susceptibility loci for type 1 diabetes using large collections of families have recently been reported. Apart from strong linkage in both studies of the HLA region on chromosome 6p, clear consistent evidence for linkage was not observed at any other loci. One possible explanation for this is a high degree of locus heterogeneity in type 1 diabetes, and we hypothesised that the sex of affected offspring, age of diagnosis, and parental origin of shared alleles may be the bases of heterogeneity at some loci. METHODS: Using data from a genome wide linkage study of 356 affected sib pairs with type 1 diabetes, we performed linkage analyses using parental origin of shared alleles in subgroups based on (1) sex of affected sibs and (2) age of diagnosis. RESULTS: Among the results obtained, we observed that evidence for linkage to IDDM4 on chromosome 11q13 occurred predominantly from opposite sex, rather than same sex sib pairs. At a locus on chromosome 4q, evidence for linkage was observed in sibs where one was diagnosed above the age of 10 years and the other diagnosed below 10 years of age. CONCLUSIONS: We show that heterogeneity tests based on age of diagnosis, sex of affected subject, and parental origin of shared alleles may be helpful in reducing locus heterogeneity in type 1 diabetes. If repeated in other samples, these findings may assist in the mapping of susceptibility loci for type 1 diabetes. Similar analyses can be recommended in other complex diseases.  相似文献   
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