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31.
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A possible association between anticardiolipin antibodies (ACA), which are a marker for increased risk of cerebral ischemia, and deficiency of free Protein S, a naturally occurring anticoagulant, has been suspected in some studies of ischemic stroke, particularly in young adults. In order to investigate this further, we prospectively studied all stroke patients ≤ 65 years of age admitted to our stroke unit during 1991–1992. A total of 66 patients with acute ischemic stroke or transient ischemic attacks (TIA) (embolic/thrombotic infarction n = 30, embolic infarction n = 13, thrombotic infarction n = 10, and TIA n = 13) were analysed for ACA, protein C and S, free protein S and antithrombin III (AT III). Traditional risk factors were scrutinized in each patient. Eight patients had some previously undetected derangement of the coagulation process; five had elevated ACA levels, four had low, free Protein S levels, and three had low AT III levels. None of the patients showed any decrease in total protein C or S levels. A striking association between the presence of ACA and free protein S deficiency was noted. All patients with free protein S deficiency had concomitant elevated ACA levels. Sixteen patients had had a previous episode of ischemic stroke/TIA or mycocardial infarction, two of them had lowered AT III levels. Thirty-four patients had one or more elevated infectious parameters but with no clear correlation to derangement of the coagulation factors. We conclude that a probable association between ACA and free protein S deficiency exist in ischemic stroke patients, and that it may have a pathogenetic importance.  相似文献   
33.
The effect of adriamycin, daunomycin, N,N-dimethyladriamycin, N,N-dimethyldaunomycin, pyrromycin, marcellomycin, and aclacinomycin A on erythroid differentiation and glycoprotein synthesis in Friend erythroleukemia cells, clone F4-6 was investigated. Whereas N-dimethylated natural anthracyclines, pyrromycin, marcellomycin, and aclacinomycin A stimulated erythroid differentiation (induction of hemoglobin synthesis), this was not seen with adriamycin, daunomycin and their N-dimethylated derivatives. The incorporation of 3H-mannose in glycoprotein was inhibited by the N-alkylated natural anthracyclines at a concentration at which they induced erythroid differentiation. N,N-Dimethyladriamycin and N,N-dimethyldaunomycin only inhibited 3H-mannose incorporation into glycoprotein at cytotoxic concentrations. However, adriamycin and daunomycin did not inhibit glycoprotein synthesis, even at high cytotoxic concentrations. Aclacinomycin A decreased the incorporation of 3H-mannose into proteins earlier than the incorporation into dolichol-linked oligosaccharide intermediates. Tunicamycin, a specific inhibitor of glycoprotein synthesis, failed to stimulate differentiation in Friend erythroleukemia cells. These results indicate a structure-specific induction of the differentiation and inhibition of glycoprotein synthesis in Friend cells by N-alkylated anthracyclines. The inhibition of glycoprotein synthesis may be involved in the induction of differentiation by N-alkylated anthracyclines, but it cannot be the only target for the differentiation-inducing effect of these substances.  相似文献   
34.
Purpose:   Benign familial neonatal convulsions (BFNC) is caused by mutations in the KCNQ2 and KCNQ3 genes, which encode subunits of the M-type potassium channel. The purpose of this study was to examine the effects of orthologous BFNC-causing mutations on seizure thresholds and the acquisition of corneal kindling in mice with heterozygous expression of the mutations.
Methods:   The effects of the Kcnq2 gene A306T mutation and the Kcnq3 gene G311V mutation were determined for minimal clonic, minimal tonic hindlimb extension, and partial psychomotor seizures. The rate of corneal kindling acquisition was also determined for Kcnq2 A306T and Kcnq3 G311V mice.
Results:   Seizure thresholds were significantly altered relative to wild-type animals in the minimal clonic, minimal tonic hindlimb extension, and partial psychomotor seizure models. Differences in seizure threshold were found to be dependent on the mutation expressed, the seizure testing paradigm, the genetic background strain, and the gender of the animal. Mutations in Kcnq 2 and Kcnq 3 were associated with an increased rate of corneal kindling. In the Kcnq2 A306T mice, an increased incidence of death occurred during and immediately following the conclusion of the kindling acquisition period.
Conclusions:   These results suggest that genetic alterations in the subunits that underlie the M-current and cause BFNC alter seizure susceptibility in a sex-, mouse strain-, and seizure-test dependent manner. Although the heterozygous mice do not appear to have spontaneous seizures, the increased seizure susceptibility and incidence of death during and after kindling suggests that these mutations lead to altered excitability in these animals.  相似文献   
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Anticardiolipin antibodies (ACA) were analysed in 502 consecutive patients admitted to our stroke unit Elevated ACA levels ≥11 units) were found in 20 of 396 patients (5%) with ischemic stroke and TIA, in none of 42 patients with cerebral haematomas and in five of 64 patients (8%) with other diagnoses than stroke. There were no statistically significant differences in occurrence of ACA in these groups. Markedly elevated ACA levels (> 20 units) were found in nine of the 396 patients (2%) with TIA/ischemic stroke. The frequency of ACA was higher in the age group 40–50 years (15%) than in the age group 50–90 years (3.6–6.0%). Re-examination in 18 of the 20 patients with ischemic stroke and elevated ACA levels after 26–395 days (mean 100 days) showed that in 10 patients ACA levels were lower (difference ≥ 6 units = 2 SD), compared to the initial value, whereas eight patients had unchanged ACA levels. The occurrence of previous deep venous thrombosis was significantly more common in patients with elevated ACA levels, otherwise there were no differences concerning earlier stroke, risk factor analysis or other laboratory parameters between patients with and without elevated ACA levels. In conclusion, we found elevated ACA levels in patients with ischemic stroke at a rather low prevalence as compared to most previous studies. The clinical relevance of ACA is uncertain, especially in patients with multiple risk factors. We recommend screening for ACA only in stroke patients < 50 years of age, or when the antiphospholipid syndrome is suspected.  相似文献   
37.
A kinetic chromogenic limulus test was carried out in order to investigate the possibility of a sensitive and specific detection of circulating endotoxin during the first 24 h of septic shock or severe sepsis in 76 patients. Two commercial kits, Whittaeker (W) and Chromogenix (C), were used. Blood culture was taken as a reference. At 1 : 10 plasma dilution (a currently used dilution in the end point limulus test) abnormal reaction kinetics were found in 13% and 41% of tests, for C and W respectively ( P  = 0.0008), resulting in unreliable results. Retesting plasma at a greater dilution, until the reaction kinetic was identical to calibration curve control values, gave similar results between the two kits and a better accuracy. Beyond a 0.5 EU mL−1 endotoxin level, the probability of Gram-negative bacteraemia was high (sensitivity = 0.53 and 0.47; specificity = 0.95 and 0.93 for C and W respectively). This kinetic limulus amoebocyte lysate (LAL) test may be useful in therapeutic decisions for treatment of endotoxaemia.  相似文献   
38.
Outcome of the treatment of invasive non-transitional cell carcinoma   总被引:1,自引:0,他引:1  
BACKGROUND: We evaluated the treatment outcomes of non-transitional cell carcinoma (non-TCC) cases after radical cystectomy. METHODS: Radical cystectomy was performed in 259 invasive bladder cancer patients in our department and of these, 59 (22.7%) were non-TCC. Primary squamous cell carcinomas (SCC), adenocarcinomas and undifferentiated cancers (UC) were grouped as non-TCC of the bladder. Of the 59 non-TCC; 32 SCC, 20 UC, five adenocarcinoma and two sarcomatoid tumor cases were demonstrated. RESULTS: The 5-year disease-specific survival rate of TCC and non-TCC cases were 48.9 and 28.2%, respectively (P = 0.0016). The 5-year disease-specific survival rates of SCC and UC were 25.1 and 23.4%, respectively. The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 6 months, respectively (P = 0.4579). The disease-specific survival rates of TCC and non-TCC cases at stage pT2NoMo were 79.1 and 27.2%, respectively (P = 0.0000). The median survival time of SCC, UC and adenocarcinoma cases were 19, 12 and 13.3 months, respectively, for the same stage. The survival time of TCC, SCC and UC cases at stage pT3NoMo were 23, 26 and 45 months, respectively (P = 0.2307). The median survival time at stages pT2-3N1Mo for the same groups were 18, 16 and 11 months, respectively (P = 0.0939). CONCLUSION: The study presented here demonstrates that both TCC and non-TCC cases have poor survival rates in locally advanced disease and that at the pT2NoMo stage the prognosis of non-TCC cases is poor when compared with TCC cases.  相似文献   
39.
Kees  UR 《Blood》1988,72(5):1524-1529
We show here that a human leukemic cell line, PER-117, bearing the markers of a T-cell precursor phenotype, can be induced to express receptors for interleukin-2 (IL-2). These IL-2 receptors could be demonstrated to mediate a physiologic response to the lymphokine for which the high-affinity form of the IL-2 receptor appears to be essential. The phenotype of PER-117 cells corresponds to the earliest identifiable stage of T-cell differentiation, which is defined by the lack of the T3-T-cell receptor complex and the presence of the 40 Kd protein recognized by monoclonal antibodies of the CD7 group. Further evidence for the clonality and T-cell lineage of this cell line was obtained by analysis of rearrangements of genes for the T-cell receptor (TCR) beta chain and for the immunoglobulin heavy-chain (IgJH) genes. PER-117 cells could be shown to have rearranged TCR beta genes but no rearrangement of the IgJH genes. Cell line PER-117 provides a model to investigate the requirements for induction of IL-2 receptors in a cell expressing the first T-cell-specific marker and may help to elucidate the role of IL-2 during thymic differentiation and in the uncontrolled proliferation of T-cell leukemias.  相似文献   
40.
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