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Synthetic pyrethroids are the major insecticides used widely in agriculture and household pest control. Deltamethrin (DM), a widely used type II pyrethroid insecticide, is a relatively potent neurotoxicant. 3-Phenoxybenzoic acid (PBA) is the major metabolite formed due to metabolism of DM. In order to illustrate the toxic response of zebrafish embryos/larvae to DM and PBA the present research was carried out. For this 4hpf embryos were treated with two concentrations of DM (100 and 200?μg/L) for 48?h and PBA (1000 and 2000?μg/L) for 96?h or 99.9% ethanol (solvent control). Early life stage parameters were observed at specified time points. DM-treated embryo/larvae exhibited increased mortality, delay in hatching time, decrease in percentage of hatched embryos, increase of heartbeat rate and decrease in blood flow; lightening of body and eye pigmentation in a dose dependent manner. Pericardial and yolk sac edema along with were also caused by DM. Along with these crooked notochord, tail deformation was noticed in hatched and unhatched embryos. In case of PBA treated embryos and larvae, increased embryos/larvae length and yolk sac size were observed. Other abnormalities like edema (yolk sac and pericardial), decreased eye and body pigmentation were also observed but in some embryos only. These were not as severe as observed in parental compound indicating that DM is more toxic than its metabolite PBA. The data contributes to a better understanding of the potential consequences of fish exposed to DM and PBA.  相似文献   
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As a consequence of the high prevalence of TorqueTeno virus (TTV) in blood donors, thalassemia patients frequently acquire various genotypes of this virus through therapeutic blood transfusions. At present, the clinical consequences of TTV infection remain indeterminate for these patients. Here, several hundred thalassemia patients were tested for the presence of TTV and its genotypes using a combination of PCR and clone-based DNA sequencing. Approximately 10% (12/118) of the patients aged 2-20 years remained negative for TTV including eight genotypes of SENV. Ferritin, aspartate-aminotransferase (AST) and alanine-aminotransferase (ALT) levels were invariably lower in TTV-negative patients (P = 0.02, <0.01, and 0.06, respectively) than in TTV-positive patients. Patients with TTV-HCV co-infection showed elevated ferritin and ALT levels compared with patients with TTV infection alone (P < 0.02 and P < 0.01). AST and ALT levels were within the normal range for all TTV-negative patients, whereas abnormal levels of AST and ALT were seen in a significant proportion of TTV-positive patients (30.7% and 33.6%, respectively) and patients with TTV-HCV co-infections (70.0% and 56.6%, respectively). Only TTV-positive patients (28.0%) and patients with TTV-HCV co-infections (36.3%) had hyper-ferritin levels (> or =3,000 ng/ml). The genotype(s) of TTV responsible for the liver dysfunction could not be determined. However, high levels of AST and ALT were found to be correlated with detection of a higher number of TTV genotypes in the patients. The data suggests that frequent and persistent TTV infection through blood transfusion is associated with hepatic dysfunction and/or damage in transfusion dependent thalassemia patients.  相似文献   
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47,XYY syndrome is a sex chromosomal anomaly in men, which may be associated with infertility and has an incidence of 0.1% of male births. The clinical and paraclinical characteristics of men suffering from this anomaly have not been fully described. In this retrospective study, we present 37 cases of 47,XYY infertile men with sperm counts varying from normal to azoospermia, referred to the Genetics Laboratory at the Royan Institute, Iran. Thirteen individuals were mosaic and 24 non-mosaics. Non-mosaic patients were classified as azoospermic (nine cases) and normospermic/oligozoospermic men (15 cases). Two of the non-mosaic and three mosaic patients had secondary infertility. In addition, 13 of them underwent IUI, IVF or ICSI, and in seven cases, there was a biochemical pregnancy. The remaining 14 patients did not have ART. The 47,XYY syndrome is relatively unusual and can be missed clinically because of the lack of symptoms and of diverse phenotypes. Diagnosis of this aneuploidy can provide valuable data for counselling and early management of the patients who undergo fertility evaluation.  相似文献   
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Anti-IgE treatment of eosinophil-associated gastrointestinal disorders   总被引:2,自引:1,他引:2  
BACKGROUND: Eosinophil-associated gastrointestinal disorders (EGIDs) are commonly associated with atopy and are being recognized with increasing frequency. Current therapy for EGIDs is inadequate. OBJECTIVE: We sought to determine the efficacy of anti-IgE therapy in EGIDs and investigate the role of IgE in disease pathogenesis. METHODS: Nine subjects with EGIDs received omalizumab every 2 weeks for 16 weeks while other therapy was held constant. Blood absolute eosinophil counts, tissue eosinophil counts, symptom scores, and free IgE levels were serially measured. Allergen skin testing and flow cytometry for basophil activation and FcepsilonRI were determined at baseline and at week 16. RESULTS: Omalizumab was associated with a decrease in absolute eosinophil count at both the week 16 (34%, P = .004) and combined weeks 12 to 16 (42%, P = .012) time points. Tissue eosinophils decreased in the duodenum (59%) and gastric antrum (69%) but did not reach statistical significance (P = .074 and .098, respectively). Esophageal eosinophil counts remained unchanged. Basophil and dendritic cell FcepsilonRI expression and free IgE levels were all significantly decreased (P < .005). Omalizumab increased the concentration of allergen required to trigger half-maximal basophil activation by 170-fold. Allergen skin test wheal and erythema responses decreased by 78% and 82%, respectively. Symptom scores were decreased at both the midstudy (63%) and end of study (70%) time points (P < .005 for both). CONCLUSION: These results demonstrate that IgE-mediated processes contribute to the generation of eosinophilic inflammation in EGIDs and suggest that anti-IgE therapy might be effective in these disorders. CLINICAL IMPLICATIONS: Anti-IgE might be a potential therapy for EGIDs.  相似文献   
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IL‐7 is a major regulator of lymphocyte homeostasis; however, little is known about the mechanisms that regulate IL‐7 production. To study Il7 gene regulation in vivo, we generated a novel IL‐7‐reporter mouse, which allows the non‐invasive quantification of Il7 gene activity in live mice and, additionally, the simultaneous activation/inactivation of target genes in IL‐7‐producing cells. With these IL‐7‐reporter mice, we identify thymus, skin and intestine as major sources of IL‐7 in vivo. Importantly, we show that IFN‐γ and the commensal microflora promote steady‐state IL‐7 production in the intestine. Furthermore, we demonstrate that the blockade of IFN‐γ signaling in intestinal epithelial cells strongly reduces their IFN‐γ‐driven IL‐7 production. In summary, our data suggest a feedback loop in which commensal bacteria drive IFN‐γ production by lymphocytes, which in turn promotes epithelial cell IL‐7 production and the survival of IL‐7‐dependent lymphocytes.  相似文献   
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