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21.
A patient with longstanding ankylosing spondylitis (AS) developed a cauda equina syndrome. The myelogram showed a block at the L2 level. Vertebral computerised tomography showed calcification in the centre of the spinal canal. The patient also had features suggestive of a diffuse idiopathic skeletal hyperostosis (DISH). Meningeal calcification has never been reported in AS, so we suggest that this is related to an associated DISH. Cauda equina syndrome has not been described in DISH, and calcification of meninges has not been reported in AS, so we suggest that the meningeal calcifications and associated cauda equina syndrome are related to DISH.  相似文献   
22.
Jennings  LK; Phillips  DR; Walker  WS 《Blood》1985,65(5):1112-1119
Hybridomas secreting monoclonal antibodies (MoAbs) to human platelet membrane glycoprotein IIb (GPIIb) were prepared by fusing cells of a mouse myeloma line to spleen cells from a BALB/c mouse immunized with purified GPIIb. Six of the hybridomas secreted MoAbs that recognized epitopes on the 23,000-dalton, disulfide-linked subunit of GPIIb, GPIIb beta. All six of these MoAbs agglutinated platelets in the absence of calcium. The agglutination titers of three of the MoAbs, however, were enhanced between 2 and 6 log2 dilutions when titrated in the presence of mmol/L of calcium. The enhancement in titer was the result of MoAb- induced platelet activation followed by platelet aggregation, a reaction that could also be initiated by the monovalent Fab fragments prepared from one of the MoAbs. The MoAbs did not significantly agglutinate platelets from patients with Glanzmann's thrombasthenia, confirming biochemical evidence that there is a paucity of GPIIb beta in the membranes of these cells. Our results show that MoAbs to epitopes on GPIIb beta initiate distinct platelet responses; therefore, they should be useful for studying the ways in which regions of surface glycoproteins are involved in platelet-platelet interactions. In addition, these reagents may prove of value in diagnosing and typing patients with Glanzmann's thrombasthenia.  相似文献   
23.
Minactivin expression in human monocyte and macrophage populations   总被引:4,自引:0,他引:4  
Adherent monolayer cultures of human blood monocytes, peritoneal macrophages, bone marrow macrophages, and colonic mucosa macrophages were examined for their ability to produce and secrete minactivin, a specific inactivator of urokinase-type plasminogen activator. All except colonic mucosa macrophages produced and secreted appreciable amounts of minactivin, but only blood monocytes were stimulated by muramyl dipeptide (adjuvant peptide) to increase production. The minactivin from each of these populations could be shown to preferentially inhibit urokinase-type plasminogen activator and not trypsin, plasmin, or "tissue"-type plasminogen activator (HPA66). A plasminogen-activating enzyme present in monocyte cultures appeared unaffected by the presence of minactivin and could be shown to be regulated independently by dexamethasone.  相似文献   
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100份大肠癌组织,用RT-PCR-SSCP检测P53基因CDNA突变;PAb1801单抗免疫组化检测P53基因蛋白搞表达并对大肠癌术对后病人作5年生存随访,比较上述2结果与大肠癌预后的关系,100例大肠癌中,RT-PCR-SSCP显示51例大肠癌P53基因CDNA突变,PAb1801阳性率62%,P53基因CDNA突变和P53基因蛋白高表达与Dukes分期无关,P53基因CDNA突变与P53基因  相似文献   
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BACKGROUND: The risk of hemorrhagic complications after extracorporeal shock-wave lithotripsy (ESWL) increases in patients with aspirin intake, but the hematoma-inducing mechanism has not been understood completely at the ultrastructural level. METHODS: The effect off shock-waves on the kidneys of male Wistar-rats (n=24) was investigated in an experimental setting using a special ESWL device. Ultrastructural examination was performed by light-, transmission electron- and scanning electron microscopy. RESULTS: Shock-wave induced tissue damage appeared in all kidneys independently of aspirin intake. Endothelial detachment, lethal cell injury, gaps and mechanical disruption of the glomerular basement membrane were regularly found. After 1 week, repair processes were completed with evidence of permanent fibrosis in some cases. CONCLUSIONS: ESWL can induce modest as well as fatal damage to renal tissue cells. Therefore, after an ESWL-induced hematoma a second ESWL should not be performed within 1 week of the first treatment.  相似文献   
29.
BACKGROUND: Although nitric oxide (NO) is thought to be beneficial in hepatic ischemia-reperfusion (I/R), the mechanisms for this effect are not well established. METHODS: To investigate the effects of endogenous NO and exogenous NO supplementation on hepatic I/R injury and their pathogenic mechanisms, serum ALT and hyaluronic acid (endothelial cell damage), and hepatic malondialdehyde and H2O2 (oxidative stress), myeloperoxidase activity (leukocyte accumulation), and endothelin (vasoconstrictor peptide opposite to NO) were determined at different reperfusion periods in untreated rats and rats receiving L-NAME, L-NAME+L-arginine, and spermine NONOate (exogenous NO donor). RESULTS: After reperfusion every parameter increased in untreated animals. Endogenous NO synthesis inhibition by L-NAME increased hepatocyte and endothelial damage as compared to untreated rats, which was reverted and even improved by the addition of L-arginine. Spermine NONOate also improved this damage. However, different mechanisms account for the beneficial effect of endogenous and exogenous NO. Oxidative stress decreased by both L-NAME and L-NAME+L-arginine, but remained unmodified by spermine NONOate. Myeloperoxidase increased by L-NAME and this effect was reverted by the addition of L-arginine, whereas no change was observed with spermine NONOate. Endothelin levels were not modified by L-NAME and L-NAME+L-arginine, but decreased with spermine NONOate. CONCLUSIONS: These results suggest that, although both endogenous and exogenous NO exert a protective role in experimental hepatic I/R injury, the mechanisms of the beneficial effect of the two sources of NO are different.  相似文献   
30.
BACKGROUND: Deep fungal and higher bacterial skin infections occur fairly frequently in Thailand. METHODS: Cases with a provisional diagnosis of deep fungal and higher bacterial infections were prospectively collected from 1994 to 1997 in the Granuloma Clinic, Department of Dermatology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand. Demographic data, clinical manifestations, causative organisms, histologic features, treatment, and outcome were investigated. RESULTS: The total cases in a 4-year period numbered 27. The male to female ratio was approximately 1:1. Mycetoma was most common, followed by chromoblastomycosis. Actinomycetoma was similar in incidence to eumycetoma. The only causative organism that could be identified among the mycetoma cases was Cladosporium carrionii, which caused mycetoma of the buttock of an aplastic anemia patient at the site of bone marrow aspiration. Surgical treatment was recommended for eumycetoma. Chromoblastomycosis was caused by C. carrionii and F. compactum and responded well with itraconazole orally. Mycotic abscesses were found in four cases, basidiobolomycosis in two cases, and cutaneous nocardiosis in one case. Cotrimoxazole was recommended in the treatment of actinomycetoma, cutaneous nocardiosis, and basidiobolomycosis. CONCLUSIONS: Localized, chronic, slow, progressive, and usually asymptomatic were the main cutaneous manifestations of deep fungal and higher bacterial skin infections. A skin biopsy for histologic study and culture identification should be performed in every suspected case. The causative organisms were found in the histologic sections of every case, but only about one-third were found by culture.  相似文献   
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