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91.
仓龙卿 《东南大学学报(医学版)》1993,(2)
分析了92例胸膜活检资料,认为其阳性率与下述因素有关:疾病种类、病例选择、活检器械、取材方法及技术、重复检查、临床医师与病理医师的配合。 相似文献
92.
阻塞性睡眠呼吸暂停综合征的临床研究 总被引:4,自引:0,他引:4
强调对阻塞性睡眠呼吸暂停综合征的认识,以达到对该病的早期诊与治疗。方法应用Autoset诊疗系统及鼻持续正压通气治疗仪,对66例OSAS患者进行确诊及序贯治疗。 相似文献
93.
G Wilms C Van Ongeval A L Baert A Claus J Bollen H De Cuyper M Eneman M Malfroid J Peuskens S Heylen 《Acta psychiatrica Scandinavica》1992,85(4):306-312
The ventricle-brain ratio (VBR) of 42 chronic schizophrenic patients was compared with that of 42 age-matched medical controls. For the schizophrenics, the relationship of various clinical parameters to the VBR was assessed, and the outcome of 12 weeks of double-blind treatment with either risperidone or haloperidol. The results confirm that schizophrenic patients have slightly enlarged lateral ventricles compared with medical controls. Only for schizophrenics, an effect of age, but not of duration of illness, was noticed. This study does not support the validity of a clinical subdivision of chronic schizophrenic patients on the basis of the VBR. Neither negative, positive nor general psychopathological symptoms, as measured by the Positive and Negative Syndrome Scale for Schizophrenia (PANSS), were related to the VBR, nor were abnormal involuntary movements or extrapyramidal symptoms. No association between season of birth or a family history of major mental disorder and VBR could be demonstrated. Treatment response was predicted by the total PANSS score and the PANSS general psychopathology subscale score at baseline. There was a trend for patients with higher VBR to have a more or haloperidol). or haloperidol). 相似文献
94.
Although extensively pursued, the central respiratory neurons have remained elusive. We departed from the more conventional physiologic and morphologic methods of system and tissue examination and cultured dissociated fetal rat cells (Fitzgerald et al., J Neurosci Res 33:579-589, 1992) from the area of the nucleus ambiguus and the nucleus tractus solitarius located within the 2 mm rostral to the obex. Pacemaker-like cells, with a regular single or bursting activity, studied at 3-5 weeks of age, responded to very small pulses of CO2 (50 ms) and low pH with an increase in spike frequency and a decrease in spike amplitude. Other irregularly beating or silent cells did not respond or else required very large pulses (> 200 ms) to do so. The pacemaker cells also responded to hypoxia induced by administration of sodium hydrosulfite with an increase in spike frequency and amplitude; high oxygen (> 600 torr) and adenosine produced a decrease in electrical activity. Most of these cells were multipolar after staining with antibodies to neuron-specific enolase (NSE) and Fragment C of tetanus toxin. They did not stain for choline acetyltransferase (ChAT). The results suggest that these cultured cells, expressing a phenotype inherently responsive to CO2 and low pH, have the characteristics of central respiratory chemoreceptors, and may be involved in the generation of the respiratory rhythm. 相似文献
95.
The development and maintenance of the normal functional integrity of the mammalian central nervous system is under the influence of a number of growth and trophic factors. One such growth factor, epidermal growth factor, has been detected in the mammalian brain and found to be associated with various brain regions and cell types. This small ubiquitous polypeptide can influence the proliferation, Metabolism, and differentiation of both glia and neurons in the central nervous system. We discuss the effects of epidermal growth factor on glial and neuronal cell function in an attempt to understand its role in development and maintenance of normal brain integrity. In addition, we review its possible implications in several pathological states in the central nervous system and speculate on therapeutic applications for this growth factor. © 1992 Wiley-Liss, Inc. 相似文献
96.
贯众提取液对革兰氏阳性球菌的抑菌作用 总被引:6,自引:0,他引:6
目的:了解贯众(Dryopteris crossirhizomz)不同提取液对革兰氏阳性球菌的抑菌作用。方法:分别用水以及3种不同pH值的70%乙醇为溶媒提取贯众干品以制备贯众提取液,利用打孔法和试管稀释法测定提取液对13种微生物的抑制效果。结果:每1ml含生药1g的贯众醇提液、水提液对革兰氏阳性菌有较强的抑制作用,尤其是革兰氏阳性球菌如金黄色葡萄球菌和甲型溶血性链球菌等。对革兰氏阴性菌和真菌的抑制作用较弱,但对普通变形杆菌则有较强的抑制作用。不同pH值的抽提溶剂对药物的有效抑菌成份的提出效果不同,抽提溶剂pH越小,有效成份的提出效果越好。结论:贯众醇提液、水提液对革兰氏阳性菌有较强的抑制作用,尤其是对革兰氏阳性球菌,而对革兰氏阴性菌和真菌的抑制作用则较弱。贯众的抗菌成份易溶于水,抽提效果随pH减小而增加。 相似文献
97.
98.
ALUN M. DAVIES 《Journal of anatomy》1997,191(4):483-491
The accessibility of the primary sensory neurons of the trigeminal system at stages throughout their development in avian and mammalian embryos and the ease with which these neurons can be studied in vivo has facilitated investigation of several fundamental aspects of neurotrophin biology. Studies of the timing and sequence of action of neurotrophins and the expression of neurotrophins and their receptors in this well characterised neuronal system have led to a detailed understanding of the functions of neurotrophins in neuronal development. The concepts of neurotrophin independent survival, neurotrophin switching and neurotrophin cooperativity have largely arisen from work on the trigeminal system. Moreover, in vitro studies of trigeminal neurons provided some of the first evidence that the neurotrophin requirements of sensory neurons are related to sensory modality. The developing trigeminal system has been studied most extensively in mice and chickens, each of which has particular advantages for understanding different aspects of neurotrophin biology. In this review, I will outline these advantages and describe some of the main findings that have arisen from this work. 相似文献
99.
Cellular expression and genetic control of ABH antigens in primary sensory neurons of marmoset, baboon and man 总被引:3,自引:0,他引:3
Rosella Mollicone David R. Davies Beryl Evans Anne Marie Dalix Rafael Oriol 《Journal of neuroimmunology》1986,10(3):255-269
ABH antigens have been demonstrated in the posterior root ganglia (PRG) of 3 primate species (marmoset, baboon and man). Their expression corresponded to the ABO phenotype of the individual and was independent of the secretor gene. In marmosets more cells were positive for H (33 +/- 9%) than for A (19 +/- 6%). In baboons A or B antigens were more easily detected (66 +/- 9%) than the H antigens (48 +/- 5%). In humans more than two-thirds of PRG cells were positive for H but only a small proportion of these were positive for A or B. The ABH antigens were found mainly in the small and intermediate-size neurons whose central processes project to lamina II of the spinal cord posterior horn. Unipolar neurons of the Gasserian ganglion, neurons of the mesencephalic nucleus of the trigeminal nerve and of some visceral ganglia have also been shown to express these antigens which are also present in the fibre layer and glomeruli of the olfactory bulbs. 相似文献
100.
The calcium-binding protein calretinin is present in an intrinsic GABAergic and an extrinsic non-GABAergic system in the rat and monkey hippocampal formation. Important species differences have been noted in hippocampal cell types immunostained for calretinin and the termination pattern of calretinin containing hypothalamic afferents in the hippocampus. In the present study, calretinin-containing neurons were visualized using immunocytochemistry in the human hippocampal formation of individuals which showed no significant neuropathological alterations. Calretinin-immunoreactivity was present exclusively in non-granule cells of the dentate gyrus and in non-pyramidal cells of Ammon's horn. Calretinin-positive neurons were found most frequently in the hilus of the fascia dentata and in strate radiatum and lacunosum-moleculare of CA1, whereas neurons in CA2 and CA3 were rarely immunostained. The majority of calretinin-immunoreactive neurons were small, bipolar or fusiform neurons. The dendritic trees of the calretinin-positive neurons were, for the most part, parallel to the dendrites of the principal cells. In the hilus, however, we observed cells with dendrites restricted to the hilar area. These dendrites were parallel to the granule cell layer. In the stratum lacunosum-moleculare, neurons with dendrites oriented parallel to the hippocampal fissure were frequently detected. In general, dendrites were smooth or sparsely spiny, displaying small conventional spines. The axons usually emerged from the proximal dendrite and could be followed over long distances. Axons were thin, had small varicosities and displayed only few collaterals which branched relatively far away from the cell body. Distinct bands of darkly stained calretinin-positive fibers occupied the innermost portion of the dentate molecular layer and the pyramidal cell layer of CA2. This distribution of calretinin-immunoreactive structures in the human hippocampus is similar to that observed in other primates but differs from that described in lower mammals, i.e., the rat. Our findings suggest that primates may share a common hippocampal calrtinin-containing system, presumably both the intrinsic GABAergic and the extrinsic hypothalamic non-GABAergic components. © 1995 Wiley-Liss, Inc. 相似文献