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961.
Jaffe  ES; Braylan  RC; Frank  MM; Green  I; Berard  CW 《Blood》1976,48(2):213-222
The neoplastic cells from seven patients with childhood lymphoblastic lymphoma were studied for cell surface markers and surface morphology in the scanning electron microscope (SEM). The cells were studied for surface immunoglobulin (Slg), complement receptors (EAC), receptors for cytophilic antibody (IgGEA), and nonimmune rosette formation with sheep red blood cells (E). In one patient the cells exclusively bound E, suggesting a T-lymphocytic origin. In two patients the cells bound EAC, but demonstrated no other B-lymphocytic markers. In two patients no markers were detected, and in two patients receptors for both E and EAC were demonstrated. Additional studies in one of these patients permitted simultaneous demonstration of both markers on the same neoplastic cells. The neoplastic cells were also examined by SEM after fixation and critical point dehydration. No consistent surface morphology was observed. In four patients the cells were predominately smooth, whereas in two patients variable numbers of surface microvilli were present. A correlation of the surface features with membrane markers could not be established. A comparison of the surface markers with clinical and cytologic features revealed clinical homogeneity in spite of the heterogeneous immunologic markers. This heterogeneity was most likely a reflection of neoplastic alteration and disordered differentiation of the cells. The observation of complement receptors on the cells of four cases is a feature not previously reported in this disease and should be investigated in other presumed T-cell malignancies.  相似文献   
962.
Two human melanoma cell lines were transduced with the human interleukin (IL)-7 and IL-2 genes using retroviral-mediated gene transfer. Stable, high-level cytokine expression was achieved. The in vitro growth of transduced tumors was unaltered. Neither of the IL-2- transduced melanoma cell lines grew in athymic mice, whereas one IL-7- transduced melanoma line showed retarded in vivo growth. This is consistent with animal studies suggesting a predominantly T-cell response to IL-7-transduced tumors and a more nonspecific response to IL-2-transduced tumors. Both IL-7- and IL-2-transduced melanoma cell lines could induce cytotoxic lymphocytes in mixed lymphocyte-tumor cultures. The expression of putative melanoma antigens (MAGE)-1 and MAGE-3 was unaltered by cytokine transduction. In one cell line, IL-7 transduction resulted in a marked inhibition of the immunosuppressive peptide transforming growth factor (TGF)beta 1. The results allow a comparison of immunobiologic properties of IL-7- and IL-2-transduced human melanoma cell lines in consideration of their use in genetically engineered tumor vaccines. IL-7 transduction results in stable cytokine expression and phenotypic alterations that appear to be favorable for enhanced immunogenicity and it deserves clinical testing.  相似文献   
963.
Predominant interstitial nephritis is a rare manifestation of systemic lupus erythematosus. Only seven cases have been reported in the literature. Owing to the rarity of this entity, the natural history of predominant interstitial nephritis in lupus has not been adequately recorded and an appropriate therapeutic approach has yet to be defined. In this report we present the case of a 25 year old woman with active systemic lupus erythematosus complicated by kidney failure and renal tubular acidosis due to predominant interstitial nephritis. We describe the course of her disease over a three year period. Seven additional patients with systemic lupus erythematosus and predominant interstitial nephritis are reviewed.  相似文献   
964.
Hancock  WW; Zola  H; Atkins  RC 《Blood》1983,62(6):1271-1279
Eight monoclonal antibodies to cell surface antigens of human monocytes were evaluated as immunologic markers for recognition of macrophages in sections of normal and diseased tissues, using immunoperoxidase and enzyme histochemical techniques. Monoclonal antibodies assessed were PHM2, PHM3, FMC17, FMC32, FMC33, FMC34, OKM1, and 63D3. Sites studied were human bone marrow, blood, lymph node, spleen, thymus, liver, kidney, lung, and peritoneal lavages, rejecting renal allografts containing inflammatory macrophages, and granulomata showing epithelioid and multinucleate giant cell formation. All antibodies bound to at least some tissue macrophages and, except for FMC32 and FMC33 antibodies, which were identically distributed, each antibody had a distinctive tissue distribution. Some antigens were shared by other bone-marrow-derived cells (megakaryocytes and cortical thymocytes), endothelium, epithelium, and dendritic cells. Antigenic differences were also detected between mononuclear phagocytes present at different sites, different stages of differentiation, and likely different states of activation. These studies provide evidence of major antigenic differences between various populations of human mononuclear phagocytes. They therefore indicate the need for careful evaluation of experiments involving the recognition of macrophages in tissue sections and smears based solely on the use of antimonocyte monoclonal antibodies.  相似文献   
965.
966.
Given the presence of odor identification impairment in individuals with schizophrenia and recent evidence of aberrant odor hedonic processing, the aim of this investigation was to examine the influence of valence and intensity on odor identification in schizophrenia patients, their first-degree family members, and young persons at clinical risk for psychosis. Participants completed the 16-item Sniffin' Stick Odor Identification Test. A logistic regression was conducted to assess the influence of valence and intensity on odor identification accuracy. Identification performance in the schizophrenia patients and youths at clinical risk for psychosis was significantly influenced by odor valence, but not intensity. Identification accuracy in first-degree family members was not influenced by valence or intensity. These data suggest that abnormalities in odor valence perception may represent an environmentally-mediated marker for hedonic disturbance that could have predictive utility in future conversion to psychosis. Further research examining the utility of odor valence measures as markers for psychosis risk is warranted.  相似文献   
967.
Abstract

The effect of cisplatinum as a potential radiosensitizer in brain tumors is controversial. We examined the effect of the combination of cisplatinum with radiation compared to radiation alone in rabbits' brain. All rabbits were irradiated and cisplatinum was injected intravenously into part of them. Therapeutic doses of cisplatinum and irradiation were given. The rabbits were euthanised at different intervals according to protocol. The general clinical and neurological condition of the rabbits was unaffected\ and histopathological examination of the rabbit's brain was normal. The purpose of this study was to establish the effect of cisplatinum followed by cranial irradiation in therapeutic doses to the normal rabbit's brain. [Neurol Res 1996; 18: 454-456]  相似文献   
968.
969.
970.
A novel deletion of at least 26 kilobase of DNA, including both alpha- globin genes, the psi alpha- and psi zeta-globin genes, but sparing the functional zeta-gene was found in a 10-year-old black boy with HbH disease and sickle cell trait. This particular deletion has not previously been described in blacks. Its existence makes it likely that the absence of Hb Barts hydrops fetalis in blacks is due to the rarity of the chromosome lacking two alpha-globin genes rather than a result of early embryonic death due to the failure to synthesize embryonic hemoglobins because of deletion of functional zeta-globin genes.  相似文献   
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