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Birds are the principle amplifying hosts for West Nile virus (WNV), and understanding the acquisition and decay of passive immunity is important to avian surveillance and diagnostics. We characterized passive transfer of WNV-neutralizing antibody from chicken (Gallus gallus domesticus) hens to eggs and chicks and the protective efficacy and decay of maternally acquired antibody over time. We also characterized age-associated changes in magnitude of viremia and examined the possibility of vertical transmission of WNV. All egg yolks and chicks from seropositive hens were maternal antibody positive. Maternal antibodies were undetectable in most chicks by 28 days post-hatch (PH), but some chicks remained protected as late as 42 days PH. By 56 days PH, chicks from immune hens had viremia profiles similar to control chicks. There were significant age-related differences in WNV-attributed morbidity and viremia levels of unprotected chicks. Vertical transmission of WNV was not detected. 相似文献
93.
Factor XIIIa in the hamartomas of tuberous sclerosis. 总被引:2,自引:0,他引:2
Factor XIII is a blood coagulation factor which may also be produced in an intracellular location. The 'a' subunit of this factor has been found in a number of different cell types and has been shown to stimulate the proliferation of fibroblasts in vitro. We have examined cutaneous, central nervous system and renal lesions from persons with tuberous sclerosis using a standard immunohistochemical assay to see if factor XIIIa is expressed in these hamartomatous growths. We found factor XIIIa in most of the stromal cells composing the skin lesions of tuberous sclerosis as well as in cells of subependymal giant cell astrocytoma of the brain and the stromal cells in renal angiomyolipoma. Expression of factor XIIIa may be of significance in the formation of fibrous growths in tuberous sclerosis. 相似文献
94.
Spleen autotransplantation. Morphological and functional follow-up after spleen autotransplantation in mice: a research summary 总被引:1,自引:0,他引:1
Miko I Brath E Nemeth N Furka A Sipka S Peto K Serfozo J Kovacs J Imre S Benko I Galuska L Sipka S Acs G Furka I 《Microsurgery》2007,27(4):312-316
In 1986, we started the research on spleen surgery aimed at saving the splenic mass after its traumatic injury, with elaboration of special resection and autotransplantation techniques. The researches started on mongrel dogs and were continued on inbred mice and beagle dogs with complex histological, imaging, and laboratory investigations, following-up the function and the regeneration of autotransplanted spleen chips. Performing research on mice provided more immunological methods, such as lymphocyte subsets, immunoglobulin levels, and monitoring the phagocytic functions. Researches showed evidence also on the presence of apoptosis, furthermore, stem cell studies on regeneration and functional restoration of the spleen chips are in progress. Our results contributed to two multidisciplinary guidelines in Hungary: (1) One of them is under preparation and underlines the importance of spleen saving methods after traumatic splenic injury; (2) The second guideline shows that hemorheological changes can be early indicators of the increased sensitivity to postsplenectomy infections. 相似文献
95.
Hepcidin, the liver-produced peptide hormone, is a principal regulator of iron homeostasis. Abnormal hepcidin production has emerged as a causative factor in several common iron disorders. Hepcidin insufficiency results in iron overload in hereditary hemochromatosis and iron-loading anemias, whereas hepcidin excess causes or contributes to the development of iron-restricted anemias in inflammatory diseases, infections, some cancers and chronic kidney disease. Not surprisingly, hepcidin and related pathways have become the target for the development of novel therapeutics for iron disorders. In this review, we will summarize the strategies and development programs that have been devised for agonizing or antagonizing hepcidin and its receptor ferroportin. 相似文献
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Three-dimensional morphology of c-Kit-positive cellular network and nitrergic innervation in the human gut. 总被引:5,自引:0,他引:5
CONTEXT:-c-Kit-positive interstitial cells of Cajal (ICC) appear to play a key role in the normal motility function and development of intestine. Nitric oxide is considered to be the most important messenger of inhibitory nonadrenergic, noncholinergic nerves in the enteric nervous system. OBJECTIVES: The aims of this study were to examine the distribution of nitrergic innervation and ICCs in normal human bowel and to demonstrate interconnections between ICCs and nitrergic nerves and smooth muscle fibers using histochemical and immunohistochemical double-staining methods with a whole-mount preparation technique and confocal laser scanning microscopy. METHODS: Full-thickness small and large bowel specimens were obtained at autopsy from 18 children who died of nongastrointestinal diseases. A whole-mount preparation was performed for all specimens, and double staining was carried out with nicotinamide adenine dinucleotide phosphate (reduced form, NADPH)-diaphorase and c-Kit immunohistochemistry. Double immunofluorohistochemistry with neuronal nitric oxide synthase and c-Kit using confocal laser scanning microscopy was also performed in all specimens. RESULTS: The whole-mount preparation facilitated 3-dimensional visualization of the meshlike network of NADPH-diaphorase-positive nerve fibers in the myenteric plexus surrounded by a reticular network of c-Kit-positive ICCs. The dense c-Kit-positive cellular network located between longitudinal and circular muscle layers and at the innermost part of circular muscle layer intermingled with the myenteric plexus. Short, fine processes of ICCs made connections with the muscle fibers and c-Kit-positive cells. CONCLUSIONS: The development of double-NADPH-diaphorase histochemistry and c-Kit immunohistochemistry staining technique in a whole-mount preparation provides an easy and useful method for investigating the association between c-Kit-positive cellular network and nitrergic neuronal network in the human bowel wall. The characteristic profiles of the c-Kit-positive cellular network and nitrergic neuronal network and their relationship with the smooth muscle fibers provide a morphologic basis for investigating intestinal motility disorders. 相似文献
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