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排序方式: 共有680条查询结果,搜索用时 750 毫秒
51.
Muralitharan S Wali YA Dennison D Lamki ZA Zachariah M Nagwa el B Pathare A Krishnamoorthy R 《American journal of hematology》2007,82(12):1099-1102
Familial hemophagocytic lymphohistiocytosis (FHL) is an autosomal recessive immune disorder, characterized by fever, hepatosplenomegaly, pancytopenia, hypertriglyceridemia, hypofibrinogenemia, markedly elevated levels of inflammatory cytokines, and impaired cytotoxic activity of lymphocytes. FHL is often fatal in early infancy. Histologic features include organ infiltration by activated macrophages and lymphocytes. Four genetic loci (FHL1, 2, 3, and 4) have been identified, of which FHL2 involves mutations in the perforin gene and is present in 20-50% of patients with FHL. We herein report the first comprehensive molecular analysis of 16 unrelated cases of FHL in ethnic Omanis. Using direct DNA sequencing analysis in 11 families, seven different mutations were identified in the coding region of the perforin gene, of which five were novel. Perforin gene defects do not seem to be involved in one-third of the cases of FHL in ethnic Omanis. 相似文献
52.
S. Rajagopal H. FangS. Jhaveri S. TanejaE.M. Dehlin S.L. SnyderJ.J. Sando G.L. Kamatchi 《Neuroscience》2009
Cav2.2 high voltage-gated calcium channels are regulated by phorbol-12-myristae, 13-acetate (PMA) via Ser/Thr protein kinase C (PKC) phosphorylation sites in the I–II linker and C-terminus of the α1 2.2 subunit. Here we show that PMA enhancement of Cav2.2 currents expressed in Xenopus oocytes can be blocked by inhibitors of PKC βII or PKC ε isozymes, as shown previously for Cav2.3 currents, and that microinjection of PKC βII or PKC ε isozymes in the oocytes expressing the WT Cav2.2 channels increases the basal barium current (IBa). The I–V plot shows a large increase in current amplitude with PKC βII and PKC ε isozymes with only a small shift in the peak IBa in the hyperpolarizing direction. The potentiation of Cav2.2 currents by microinjection of PKC βII and PKC ε isozymes was not altered by the inhibition of G proteins with GDPβS. The combination of isozyme specific inhibitors with previously generated Ser/Thr to Ala mutants of α1 2.2 subunit revealed that PKC βII or PKC ε isozymes (but not PKC α or δ) can provide full enhancement through the stimulatory site (Thr-422) in the I–II linker but that PKC ε is better at decreasing channel activity through the inhibitory site Ser-425. The enhancing effect of PKC βII or ε at Thr-422 is dominant over the inhibitory effect at Ser-425. Injected PKC βII also enhances Cav2.2 current when any of the potential stimulatory sites (Ser-1757, Ser-2108 and Ser-2132) are available in the C-terminus. PKC ε provides lesser enhancement with C-terminal sites and only with Ser-2108 and Ser-2132. Sites Ser-1757 and Ser-2132, but not Ser-2108, are dominant over the inhibitory site Ser-425. Collectively, these results reveal a hierarchy of regulatory sites in Cav2.2 channels. Site-specific regulation by different PKC isozymes may allow graded levels of channel activation and susceptibility or resistance to subsequent stimulatory events. 相似文献
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54.
Lebedeva IV Emdad L Su ZZ Gupta P Sauane M Sarkar D Staudt MR Liu SJ Taher MM Xiao R Barral P Lee SG Wang D Vozhilla N Park ES Chatman L Boukerche H Ramesh R Inoue S Chada S Li R De Pass AL Mahasreshti PJ Dmitriev IP Curiel DT Yacoub A Grant S Dent P Senzer N Nemunaitis JJ Fisher PB 《International journal of oncology》2007,31(5):985-1007
Subtraction hybridization applied to a 'differentiation therapy' model of cancer employing human melanoma cells resulted in the cloning of melanoma differentiation associated gene-7/interleukin-24 (mda-7/IL-24). Initial studies confirm an inverse correlation between mda-7 expression and melanoma development and progression. Forced expression of mda-7 by means of a plasmid or via a replication incompetent adenovirus (Ad.mda-7) promotes growth suppression and induces apoptosis in a broad array of human cancers. In contrast, mda-7 does not induce growth suppressive or toxic effects in normal cells. Based on structure (containing an IL-10 signature motif), secretion by cells (including subsets of T-cells) and location on chromosome 1q (in an area containing IL-10-family genes), mda-7 has now been renamed mda-7/IL-24. Studies by several laboratories have uncovered many of mda-7/IL-24's unique properties, including cancer-specific apoptosis-induction, cell cycle regulation, an ability to inhibit angiogenesis, potent 'bystander antitumor activity' and a capacity to enhance the sensitivity of tumor cells to radiation, chemotherapy and monoclonal antibody therapy. Moreover, based on its profound cancer tropism, substantiated by in vivo human xenograft studies in nude mice, mda-7/IL-24 (administered as Ad.mda-7) was evaluated in a phase I clinical trial in patients with melanomas and solid cancers. These studies document that mda-7/IL-24 is well tolerated and demonstrates evidence of significant clinical activity. In these contexts, mda-7/IL-24 represents a unique cytokine gene with potential for therapy of human cancers. The present review focuses on three unique properties of mda-7/IL-24, namely its potent 'bystander antitumor activity', ability to sensitize tumor cells to radiation, and its antiangiogenesis properties. Additionally, an overview of the phase I clinical trial is provided. These studies affirm that mda-7/IL-24 has promise for the management of diverse cancers. 相似文献
55.
Kumar RS Sunderam RS Sivakumar T Sivakumar P Sureshkumar R Kanagasabi R Vijaya M Perumal BP Gupta M Mazumdar UK Kumar MS Kumar KA 《The American journal of Chinese medicine》2007,35(1):103-114
The aim of this study is to investigate the antioxidant defense system induced by the methanol extract of Bauhinia racemosa L.(MEBR) against N-nitrosodiethylamine (NDEA)-induced hepatocarcinogenesis in Wister albino rats. The effects of MEBR on surface visible macroscopic (Morphometry) liver lesions (neoplastic nodules) and the levels of serum enzymes, lipid peroxidation and antioxidants were evaluated in NDEA-induced hepatocarcinogenesis in rats. In rats treated, with NDEA, significantly elevated levels of serum enzymes (SGOT, SGPT and ALP), bilirubin and decreased levels of protein and uric acid were observed. Significantly elevated amount of malondialdehyde (MDA), the end product of lipidperoxidation, indicated higher levels of lipid peroxidation, which was accompanied by significantly decreased levels of antioxidants like vitamin C, vitamin E, reduced glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). Administration of MEBR was able to suppress nodule development/hepatocellular lesion formation in rats. The extract treatment increases in antioxidant levels and dramatic decreases in lipid peroxidation levels. MEBR also produced a protective effect by decreasing the level of serum enzymes, bilirubin and increased the protein and uric acid levels. The results suggest that MEBR exert chemopreventive effects by suppressing nodule development and decreasing lipid peroxidation and enhancing the levels of antioxidants in NDEA carcinogenesis by reducing the formation of free radicals. 相似文献
56.
57.
S. Rajagopal M. van der Gaag G. van der Velde H. A. Jenner 《Archives of environmental contamination and toxicology》2002,43(3):0296-0300
Though the Conrad's false mussel, Mytilopsis leucophaeata, is an important fouling animal in industrial cooling water systems, there are no published reports on the tolerance of this
species to chlorination. A series of experiments was conducted to determine the effects of mussel size (2–20 mm shell length),
season (breeding versus nonbreeding), nutritional status (fed versus starved) and acclimation temperature (5–30°C) on the
mortality pattern of M. leucophaeata under continuous chlorination (0.25–5 mg/L). The effect of mussel size on M. leucophaeata mortality in the presence of chlorine was significant, with 10 mm size group mussels showing greater resistance. At 0.25
mg/L residual chlorine, 2 mm size group mussels took 89 days to reach 100% mortality, whereas 10 mm size group mussels took
109 days. M. leucophaeata collected during nonbreeding season (December–April) was more tolerant to chlorine than those collected during breeding season
(June–October). Nutritional status of the mussel had no significant influence on the chlorine tolerance of the mussel: fed
and starved mussels succumbed to chlorine at equal rates. The effect of acclimation temperature on M. leucophaeata mortality in the presence of chlorine was significant. At 0.5 mg/L residual chlorine, mussels acclimated at 5°C required
99 days to reach 95% mortality, whereas mussels acclimated at 30°C required 47 days. A comparison of present data with previous
reports suggests that resistance of M. leucophaeata to chlorination is higher than other mussel species causing fouling problems in The Netherlands (Mytilus edulis and Dreissena polymorpha).
Received: 18 October 2001/Accepted: 4 March 2002 相似文献
58.
Unusual Presentations of Duodenal Tuberculosis 总被引:2,自引:0,他引:2
K. V. Nair M.D. D.M. F.A.C.G. C. Ganesh Pai M.D. K. P. Rajagopal M.S. V. N. Bhat M.S. M.Ch. Malini Thomas M.D. 《The American journal of gastroenterology》1991,86(6):756-760
Gastrointestinal tuberculosis is still rampant in underdeveloped countries and can mimic other gastrointestinal (GI) disorders. Herein we report four cases of isolated proximal duodenal tuberculosis, without involvement of other parts of the GI tract. The clinical presentation in three of them resembled that of peptic ulcer disease, and one had features of gastric outlet obstruction. On investigation, one of these patients had a pyeloduodenal fistula. The limitations of clinical evaluation, radiology, and endoscopy are stressed, and the value of surgical biopsy is highlighted. 相似文献
59.
Locus assignment of human a globin mutations by selective amplification and direct sequencing 总被引:4,自引:0,他引:4
Catherine Dodé Jacques Rochette Rajagopal Krishnamoorthy 《British journal of haematology》1990,76(2):275-281
We describe a simple approach for molecular characterization and locus assignment of structural mutants by direct sequencing of enzymatically amplified DNA selective to alpha 1 and alpha 2 globin gene regions. Nucleotide substitution of two structural variants (Stanleyville II alpha 2(78Lys) and J Mexico alpha 2(54Glu) were determined and their encoding loci were specified. The amplified segment encompasses sequences upstream of the CAAT box to downstream of the Poly(A) addition signal. Hence all of the alpha globin structural variants and most of the nondeletion alpha thalassaemic mutants should be characterizable by this approach. 相似文献
60.