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51.
52.
Smith  R; Rosen  JM; Gallo  LN; Alderson  PO 《Radiology》1985,156(3):797-800
Gallbladder nonvisualization in cholescintigraphy has been shown to be a reliable finding in acute cholecystitis. In some cholescintigrams, we have observed faintly increased pericholecystic hepatic activity in conjunction with gallbladder nonvisualization. To determine the frequency and significance of the pericholecystic hepatic activity finding, we evaluated 334 consecutive adult patients who had cholescintigrams with technetium-99m diisopropylphenylcarboamoyl iminodiacetic acid. Pericholecystic hepatic activity was seen in 21% of the abnormal scans demonstrating gallbladder nonvisualization but in none of the other scans. Thirteen of these patients underwent surgery; 11 (85%) were found to have acute cholecystitis, and two (15%) had chronic cholecystitis. Four patients (31%) had acute gangrenous cholecystitis, and five (39%) had cholecystitis complicated by gallbladder perforation. The pericholecystic hepatic activity sign is not specific for gangrenous cholecystitis or gallbladder perforation but does reliably indicate inflammatory gallbladder disease and is associated with a relatively high incidence of cholecystitis complicated by perforation.  相似文献   
53.
54.
Conclusion A detailed study of the reaction of thioacetamide, thiobenzamide, thiobenzoic acid, thiophenol and ethanethiol (emitted from industrial stacks or as industrial wastewater effluents and ultimately becoming environmental pollutants) with Chloramine-T has been made. Odor studies based on the sensory approach, have been performed on the reactants as well as the reaction mixtures containing the oxidation products, using odor test panels to determine the odor threshold levels. In all cases the median odor threshold concentration has been raised substantially by reaction with CAT. From the preliminary studies it is concluded that this oxidative technique has potential application in air and water pollution odor control.  相似文献   
55.
The latest developments and ideas in the therapy of leprosy are discussed, the need for long-term studies being stressed. The therapeutic efficacy and effective dosages of some sulfones (especially diaphenylsulfone), thiambutosine and long-acting sulfonamides such as sulfamethoxine and sulfalene, are considered. The possibilities for two newer drugs, 4,4′-diacetyldiaminodiphenylsulfone and clofazimine (B-663), both still in the early stages of evaluation, are also described and the potential value of thalidomide in treatment of the lepra reaction is discussed. The authors make a number of recommendations for controlled trials and lines of investigation and, in particular, favour a biochemical approach to the correction of defective host defences. Diaphenylsulfone is still considered the drug of choice for use in the therapy of leprosy.  相似文献   
56.
To validate the use of 99mTc-PIPIDA in the diagnosis of biliary tract disease, 117 patients with clinical symptoms of acute cholecystitis were prospectively scanned as an initial screening test. The accuracy of the test was evaluated on the basis of surgical pathology in 59 patients. Three groups were defined: cystic duct obstruction, common duct obstruction, and normal scan. The diagnostic accuracy of the test for acute cholecystitis was 97%. Complete common duct obstruction was confirmed at surgery in 12 patients (100%). A normal scan helped to rule out acute cholecystitis. Jaundice did not influence the reliability of the method. Hepatobiliary scanning is an accurate, safe, and rapid diagnostic test for acute cholecystitis.  相似文献   
57.
The first recombinant endostatin that elicited strong antitumor activity was expressed in Escherichia coli and administered as a suspension. Under these conditions, the protein retained its full antiangiogenic activity. Lack of requirement for a folded structure prompted us to investigate antitumor properties of synthetic peptides corresponding to different regions of endostatin. Here, we show that the entire antitumor, antimigration, and antipermeability activities of endostatin are mimicked by a 27-amino-acid peptide corresponding to the NH2-terminal domain of endostatin. This peptide contains three histidines that are responsible for zinc binding. Mutations of the zinc-binding histidines abolished its antitumor and antimigration activities, but not antipermeability properties.  相似文献   
58.
Biochemical estimation of NADH concentration is a useful method for monitoring cellular metabolism, because the NADH/NAD+ reduction-oxidation pair is crucial for electron transfer in the mitochondrial electron chain. In this article, we present a novel method for deriving functional maps of intracellular reduction-oxidation ratio in vivo via measurement of the fluorescence lifetimes and the ratio of free and protein-bound NADH using two-photon fluorescence lifetime imaging (FLIM). Through systematic analysis of FLIM data from the control cells, it was observed that there is a statistically significant decrease in the fluorescence lifetime of both free and protein-bound NADH and the contribution of protein-bound NADH as cells progress from an early to logarithmic to confluent phase. Potassium cyanide (KCN) treatment and serum starvation of cells yielded similar changes. There was a statistically significant decrease in the fluorescence lifetime of protein-bound and free NADH at the early and logarithmic phase of the growth curve and a statistically significant decrease in the contribution of protein-bound NADH relative to that observed in the control cells at all three phases of the growth curve. The imposed perturbations (confluence, serum starvation, and KCN treatment) are all expected to result in an increase in the ratio of NADH/NAD+. Our studies suggest that the fluorescence lifetime of both the free and the protein-bound components of NADH and the ratio of free to protein-bound NADH is related to changes in the NADH/NAD+ ratio.  相似文献   
59.
女性常见的妇科疾病如子宫内膜异位症、子宫内膜癌、乳腺癌、Sheehan综合征等,其病程中体内雌激素水平变化,直接或间接地影响骨转换水平,导致骨量变化。本文研究不同疾病状态下,疾病本身因素或手术及药物治疗对女性卵巢功能和雌激素水平的影响,从而影响骨转换率,导致继发性骨质疏松。有助于预防和治疗女性激素相关性骨量下降和骨质疏松,提高女性患者的生活质量。  相似文献   
60.

Objective

Male (NZW × BXSB)F1 mice develop antiphospholipid syndrome (APS) and proliferative glomerulonephritis that is markedly accelerated by the Yaa locus encoding an extra copy of Tlr7. Female (NZW × BXSB)F1 mice with only 1 active copy of Tlr7 develop late‐onset glomerulonephritis but not APS. Because a major function of Toll‐like receptor 7 is to induce type I interferons (IFNs), our goal was to determine whether IFNα can induce or accelerate the manifestations of systemic lupus erythematosus (SLE) in female (NZW × BXSB)F1 mice.

Methods

Eight‐week‐old female (NZW × BXSB)F1 mice were injected with a single dose of adenovirus expressing IFNα. Mice were monitored for the development of thrombocytopenia and proteinuria. Sera were tested for anticardiolipin and anti‐Sm/RNP antibodies. Mice were killed at 17 or 22 weeks of age, and their kidneys and hearts were examined histologically and by immunohistochemistry. Spleen cells were phenotyped, and enzyme‐linked immunospot assays for autoantibody‐producing B cells were performed.

Results

IFNα markedly accelerated nephritis and death in female (NZW × BXSB)F1 mice. A significant increase in spleen cell numbers associated with a striking increase in the number of activated B and T cells was observed. Marginal‐zone B cells were retained. IFNα‐induced increased titers of autoantibodies were observed, but thrombocytopenia was not observed. Cardiac damage was milder than that in male mice.

Conclusion

IFNα accelerates the development of renal inflammatory disease in female (NZW × BXSB)F1 mice but induces only mild APS and does not induce thrombocytopenia. The effect of IFNα on SLE disease manifestations is strain dependent. These findings are relevant to our understanding of the physiologic significance of the IFN signature.
  相似文献   
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