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31.
Abstract After adoption of the anti-hepatitis C virus (C100-3) test, the incidences of definite and suspected cases of post-transfusional hepatitis (PTH) were 3.3% (7/209) and 7.2% (15/209), respectively. Four patients with definite PTH and seven patients with suspected PTH became positive for hepatitis C virus (HCV)-related antibodies or HCV-RNA after transfusion. These cases that became positive for anti-HCV or HCV-RNA showed a peak of alanine aminotransferase (ALT) more than 4 weeks after operation. Only rare cases that showed ALT peaks within 4 weeks after operation became positive for HCV-related antibodies or HCV-RNA. The peak ALT levels in cases showing positive conversion tended to be higher than those in cases showing no conversion. Judging from these results, cases of suspected PTH include those of transient liver disease attributable to surgery as well as clear cases of HCV infection. Thus new diagnostic criteria are required including data on HCV antibodies or HCV-RNA.  相似文献   
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In segment couplings by the mixed anhydride method using isobutyloxycarbonyl chloride, the use of copper(II) chloride as an additive suppressed racemization completely in the same manner as in the carbodiimide method reported previously. This was confirmed by employing a number of couplings between Z-dipeptides and amino acid esters. The racemization-suppressing effect of other compounds were also evaluated by employing one of these model couplings to be at best only limitedly effective. Copper(II) chloride was effective also in the related method using EEDQ. Thus, in the couplings where a low level of racemization was observed without an additive, the addition of copper(II) chloride eliminated racemization even at ambient temperature where EEDQ is usually used. The effectiveness of copper(II) chloride was confirmed also in the BOP-C1 method. In the presence of HOBt racemization was reduced to a low but still detectable level, while it was suppressed completely by the addition of copper(II) chloride.  相似文献   
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Abstract— We investigated the metabolism of tolbutamide by using synthetic 1-butyl-3-(p-formylphenyl)sulphonylurea (ATB), an intermediate in the metabolic pathway of tolbutamide. ATB (40 mg kg?1) administered intravenously to rabbits was oxidized to 1-butyl-3-(p-carboxyphenyl)sulphonylurea (CTB) and also reduced to 1-butyl-3-(p-hydroxymethylphenyl)sulphonylurea (HMTB). Therefore, it is likely that in the metabolism of tolbutamide, the oxidation of HMTB to ATB involved the reverse reaction, suggesting the reduction of ATB to HMTB. The oxidation of ATB to CTB was inhibited by disulfiram pretreatment. ATB was detected in the blood following intravenous administration of HMTB in rabbits pretreated with disulfiram. These results, confirm that ATB is an intermediate in the oxidative metabolism of tolbutamide in the rabbit.  相似文献   
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Background/Aims: Vascular endothelial growth factor‐C (VEGF‐C) is thought to be an important factor in tumor angiogenesis/lymphangiogenesis, but its role in hepatocellular carcinoma (HCC) has not yet been fully investigated. Methods: We immunohistochemically examined VEGF‐C expression in surgically resected tissues of 90 HCC. Results: In the 78 HCC with a single histological grade, VEGF‐C expression was significantly stronger in poorly differentiated HCC than in well‐ (P = 0.003) or moderately differentiated HCC (P = 0.0002). A ‘nodule‐in‐nodule’ case presented VEGF‐A expression in the well‐differentiated component and VEGF‐C expression in the moderately–poorly differentiated component. According to nodular diameter, VEGF‐C expression was significantly higher in nodules of 3.0 cm or larger (P = 0.0263). Extrahepatic metastases seen in seven cases expressed VEGF‐C. In 20 of the 28 cases who were able to be followed up, the frequency of intrahepatic recurrence tended to be higher and extrahepatic metastasis was significantly higher in the cases who had VEGF‐C expression in the tumor casts of the intrahepatic portal/hepatic vein branches than other cases without the expression (P = 0.0139). Disease‐free survival time tended to be shorter in cases with VEGF‐C expression in tumor casts of the portal/hepatic vein than in those without VEGF‐C expression (P = 0.053; log–rank test). Conclusions: VEGF‐C expression is related to the progression of HCC, and VEGF‐C expression in tumor casts of the intrahepatic portal/hepatic vein is considered to be a factor indicating recurrence/metastasis sites.  相似文献   
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Background and Aim: We investigated the antiproliferative effects of interferon‐alpha (IFN‐α) and 5‐fluorouracil (5‐FU) in combination on a hepatocellular carcinoma (HCC) cell line. Method: In the in vitro study, IFN‐α and/or 5‐FU was added to the culture of the poorly differentiated‐type HCC cell line, HAK‐1B, and their antiproliferative effects and additional or synergic effects in combination treatment were examined. In the in vivo study, HAK‐1B cells were transplanted into nude mice and the changes in tumor volume and weight, apoptosis, BrdU and cyclin A positive cells, and artery‐like blood vessels were investigated. Expressions of angiogenesis factors and IFN‐α receptor (IFNAR‐2) were examined in the developed tumors. Results: In vitro growth of HAK‐1B cells was suppressed dose‐dependently to 5‐FU, but the addition of IFN‐α did not induce additional or synergic effects. In vivo growth in terms of tumor diameter and weight was suppressed at most in the IFN‐α + 5‐FU (combination) group, that is, the tumor volume became 29.3% and the tumor weight became 54.7% of the control. In the combination group, numbers of BrdU‐positive S‐phase cells and cyclin A positive cells increased together with the increase in apoptotic cells, but there was no significant relation between the tumor shrinkage effects and angiogenesis factors or artery‐like blood vessels. In the combination group, INFAR‐2 decreased significantly in comparison to the other groups. Conclusion: The synergic growth‐suppression effects in the current in vivo study using the combination treatment are attributable to the enhanced induction of S‐phase arrest and of apoptosis.  相似文献   
39.
hERG(G487R) Channel . Introduction: Mutations of human ether‐à‐go‐go‐related gene (hERG), which encodes a cardiac K+ channel responsible for the acceleration of the repolarizing phase of an action potential and the prevention of premature action potential regeneration, often cause severe arrhythmic disorders. We found a novel missense mutation of hERG that results in a G487R substitution in the S2–S3 loop of the channel subunit [hERG(G487R)] from a family and determined whether this mutant gene could induce an abnormality in channel function. Methods and Results: We made whole‐cell voltage‐clamp recordings from HEK‐293T cells transfected with wild‐type hERG [hERG(WT)], hERG(G487R), or both. We measured hERG channel‐mediated current as the “tail” of a depolarization‐elicited current. The current density of the tail current and its voltage‐ and time‐dependences were not different among all the cell groups. The time‐courses of deactivation, inactivation, and recovery from inactivation and their voltage‐dependences were not different among all the cell groups. Furthermore, we performed immunocytochemical analysis using an anti‐hERG subunit antibody. The ratio of the immunoreactivity of the plasma membrane to that of the cytoplasm was not different between cells transfected with hERG(WT), hERG(G487R), or both. Conclusion: hERG(G487R) can produce functional channels with normal gating kinetics and cell‐surface expression efficiency with or without the aid of hERG(WT). Therefore, neither the heterozygous nor homozygous inheritance of hERG(G487R) is thought to cause severe cardiac disorders. hERG(G487R) would be a candidate for a rare variant or polymorphism of hERG with an amino acid substitution in the unusual region of the channel subunit. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1246–1253, November 2012)  相似文献   
40.
Prostaglandin E1 (PGE1) has been reported to have, experimentally and clinically, a protective effect against liver damage. This effect may result from the relaxation of hepatic stellate cells, whose contraction induces vasoconstriction of hepatic sinusoids. However, prostaglandins are unstable and a new drug delivery system is necessary to administer a sufficient amount of prostaglandin to achieve a protective effect in the liver. The aim of the study is to investigate the effects of lipo-prostaglandin E1 (lipo-PGE1) which has a novel drug delivery system on the stellate cell contraction induced by endothelin-1 in vitro. Lipo-PGE1 inhibited endothelin-1-induced stellate cell contraction in concentrations of 10, 30 and 50 ng/mL. Therefore, lipo-PGE1 may show a cytoprotective effect in the liver through the relaxation of stellate cells and an increase in the hepatic sinusoidal blood flow.  相似文献   
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