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Nand L. Sharma Vikram K. Mahajan Neelam Gupta Nitin Ranjan and Anju Lath 《Journal of cutaneous pathology》2009,36(4):486-492
Ehlers-Danlos syndrome – vascular type, the only lethal form, is rarely reported in dermatology literature. It is characterized by translucent, atrophic skin, easy bruising, arterial, intestinal and/or uterine fragility manifesting as varicose veins, aneurysms and vascular/visceral/uterine rupture. As its dermatopathologic features are not well elucidated, diagnosis is often made after a catastrophic complication or at autopsy. This 36 year-old non-consanguineous male had brown-black plaques with atrophy and frequent ulceration over legs and dorsal feet and tortuous varicose veins around ankles for the past 15 years. Perivenous skin was translucent and hypopigmented. He had multiple and ecchymotic keloids and small atrophic, pityriasis versicolor-like lesions over trunk. He did not have hypermobile/hyperextensible skin and joints and showed no systemic or investigative abnormality. Histopathologic features of atrophic lesion included blood extravasation in atrophic epidermis/dermis, focal clustering and dilatation of blood vessels, malformed vessel walls, abundant hemosiderin in the dermis and homogenously stained/whorled patterned collagen especially around blood vessels. Pathology of keloidal lesion showed new collagen and vascular fragility. These histopathologic features appear of diagnostic value especially in patients who have compatible clinical findings but cannot afford confirmation by biochemical testing for abnormal synthesis of type III procollagen or identification of mutations in the COL3A1 gene. 相似文献
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An out line of the scheme of training specialists in Otorhinolaryngology-Head and Neck Surgery (ORL-HNS) in South Africa is
given and the difference with Indian training discussed 相似文献
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Four week swim exercise schedule (45 min day-1, 6 days each week) in rats led to a significant adaptive change in functional responsiveness of dopamine receptors (auto-receptors) in the nigrostriatal and mesolimbic system that was evident from the modification of behavioural responses elicited by a low dose of apomorphine, a direct acting dopamine receptor agonist. Thus, a remarkable increase in yawning response, development of full blown stereotypy, as well as profound attenuation of locomotory and hypothermic response was observed in exercise-trained rats as compared with the non-exercise group (control), following intraperitoneal administration of 0.3 mg kg-1 of apomorphine. 相似文献
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Regulation of immunoglobulin heavy-chain gene rearrangements 总被引:1,自引:0,他引:1
Summary: Regulated assembly of antigen receptor gene segments to produce functional genes is a hallmark of B‐ and T‐lymphocyte development. The immunoglobulin heavy‐chain (IgH) and T‐cell receptor β‐chain genes rearrange first in B and T lineages, respectively. Both loci require two recombination events to assemble functional genes; D‐to‐J recombination occurs first followed by V‐to‐DJ recombination. Despite similarities in overall rearrangement patterns, each locus has unique regulatory features. Here, we review the characteristics of IgH gene rearrangements such as developmental timing, deletion versus inversion, DH gene segment utilization, ordered recombination of VH gene segments, and feedback inhibition of rearrangement in pre‐B cells. We summarize chromatin structural features of the locus before and during recombination and, wherever possible, incorporate these into working hypotheses for understanding regulation of IgH gene recombination. The picture emerges that the IgH locus is activated in discrete, independently regulated domains. A domain encompassing DH and JH gene segments is activated first, within which recombination is initiated. VH genes are activated subsequently and, in part, by interleukin‐7. These observations lead to a model for feedback inhibition of IgH rearrangements. 相似文献
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BACKGROUND: Apart from traditional markers studied among a few numerically small, geographically defined surveys among Mongoloid populations in northeastern parts of India, very little is known about their genomic diversity at the molecular level. PRIMARY OBJECTIVE: This study seeks to investigate how best the variable number tandem repeat (VNTR) and short tandem repeat (STR) loci together can detect the patterns of the genetic affinity among five geographically contiguous, linguistically and socio-culturally diverse Mongoloid-affiliated populations of Manipur in northeastern regions of India. SUBJECT AND METHODS: Blood samples were collected from unrelated and randomly selected volunteers of five ethnic populations (Meitei, Kuki, Naga, Hmar and Manipuri Muslim) from different parts of the state. Allelic variation in four minisatellite loci (D1S7, D4S139, D5S110 and D17S79) and three STR loci (vWA, FESFPS and F13AO1) was studied. RESULTS: Average heterozygosity values among the five groups for the minisatellite range from 68% to 94%, while the hypervariable three STR loci were between 60% and 88%. In the populations, all the studied loci were highly polymorphic, with almost no departure from Hardy-Weinberg equilibrium. The gene differentiation for the VNTR loci was lower and moderate (G(st) = 0.030) in comparison with microsatellites (G(st) = 0.043). The neighbour-joining method of clustering based on both type of molecular markers reveals a close cluster for the tribal groups of Kuki, Naga and Hmar, while Manipur Muslim stand distinct in both the trees. The clustering pattern obtained from the combined DNA marker loci matches more closely the pattern from STR loci than that obtained from VNTR loci. CONCLUSIONS: The results reinforce that using both VNTR and STR loci in detecting regional genetic affinity among the populations is more effective than using VNTR or STR independently, and also confirm the results obtained from the serological and electrophoretic data. However, the clustering pattern obtained from combined DNA markers is more in conformity with the pattern obtained by STR loci rather than with VNTR loci. Despite linguistic, geographical and cultural barriers, the populations show genetic affinity among the four populations except in the case of the migrant Manipur Muslim group. 相似文献
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BACKGROUND: Effective management of breast cancer is dependent on adequate pathological reporting of the surgical specimen. OBJECTIVE: To describe the frequency with which histopathological features of known prognostic importance are routinely recorded. STUDY POPULATION: 885 cases of invasive breast cancer diagnosed in NHS laboratories in Lancashire and Greater Manchester. METHODS: Pathology reports were reviewed for details for tumour histological type, size, and grade, the presence or absence of tumour in blood or lymphatic vascular channels, and a comment on the proximity of tumour to the lines of surgical excision. Laboratories were categorised according to their throughput of cases of breast cancer, involvement in the breast screening programme, and whether they were attached to a teaching hospital. RESULTS: Histological type, tumour size, presence or absence of tumour in vascular channels, and adequacy of excision were recorded for 843 (95%), 803 (91%), 436 (49%), and 761 (86%) cases, respectively. Non-screening and low throughput laboratories were significantly less likely to record certain histopathological features. No significant differences were observed between teaching and non-teaching hospitals. CONCLUSIONS: The substantial interlaboratory variation in the histopathological reporting of breast cancers can, in part, be related to throughput of cases and involvement in the breast screening programme. 相似文献