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OBJECTIVE: The aim is to compare naturally conceived twins with twins conceived by assisted reproductive techniques (ART) by means of perinatal outcome, behavioural patterns and psychomotor development. MATERIAL AND METHODS: Three hundred and five spontaneous and 119 assisted twins were compared in aspects of behavioural patterns, mental and psychomotor development, as well as maternal and gestational age, foetal presentation, birth weight, sex, Apgar scores, perinatal complications, delivery route, and admission to neonatal intensive care unit (NICU) RESULTS: Although the maternal age was higher in assisted twins, the mean gestational age and birth weight of assisted twins were significantly less than those of spontaneous twins. The assisted twins did not differ from the naturally conceived twins in aspects of presentation, Apgar scores, admission to NICU and perinatal complications. However, caesarean section rate and the delivery rate of male foetuses were significantly higher in assisted twins. During the first year of life, retardation in mental and psychomotor development was more pronounced in assisted twins. Also assisted twins experienced behavioural problems and difficulties in parent-child interactions more frequently. CONCLUSIONS: Although twins born to assisted pregnancies had significantly shorter duration of gestation and thus less birth weight, their perinatal outcome was similar to that of spontaneous twins. The mothers of assisted twins may be keener on getting intensive prenatal care, which might in turn help to diminish any possible maternal and foetal risks. However, assisted twins showed significantly retarded psychomotor and mental development and experienced problems with environmental factors more frequently during their first year.  相似文献   
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AIM: To determine the role of inflammatory cytokines and reactive oxygen species (ROS) in childhood reflux esophagitis. METHODS: A total of 59 subjects who had complaints suggesting GERD underwent esophagogastroduoden oscopy. Endoscopic and histopathologic diagnosis of reflux esophagitis was established by Savary-Miller and Vandenplas grading systems, respectively. Esophageal biopsy specimens were taken from the esophagus 20% proximal above the esophagogastric junction for conventional histopathological examination and the measurements of ROS and cytokine levels. ROS were measured by chemiluminescence, whereas IL-8 and MCP-1 levels were determined with quantitative immunometric ELISA on esophageal tissue. Esophageal tissue ROS, IL-8 and MCP-1 levels were compared among groups with and without endoscopic/histo- pathologic esophagitis. RESULTS: Of 59 patients 28 (47.5%) had normal esophagus whereas 31 (52.5%) had endoscopic esophagitis. In histopathological evaluation, almost 73% of the cases had mild and 6.8% had moderate degree of esophagitis. When ROS and chemokine levels were compared among groups with and without endoscopic esophagitis, statistical difference could not be found between patients with and without esophagitis. Although the levels of ROS, IL-8 and MCP-1 were found to be higher in the group with histopathological reflux esophagitis, this difference was not statistically significant. CONCLUSION: These results suggest that the grade of esophagitis is usually mild or moderate during childhood and factors apart from ROS, IL-8 and MCP-1 may be involved in the pathogenesis of reflux esophagitis in children.  相似文献   
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The angiotensin II receptor, losartan, has been found to inhibit platelet aggregability to some extent in in vitro experiments. There have been conflicting results about the in vivo effects of losartan. We sought to clarify the in vivo effect of losartan on platelet aggregation. Forty patients with grade I essential hypertension were treated with losartan for 3 weeks. Platelet aggregation tests with adenosine diphosphate (ADP) and ristocetin were analyzed and compared before and at the end of the study. Losartan effectively decreased systolic (SBP) and diastolic (DBP) blood pressure. Mean SBP before and after treatment was 159.6 ± 12.8 and 149.2 ± 17.3mmHg, respectively. Mean DBP decreased from 93.7 ± 8.2 to 87.7 ± 10.3mmHg after treatment. The results of the platelet aggregation tests with ADP and ristocetin were not significantly different when both rate and amplitude of maximal aggregation were included. Peak platelet aggregation with ADP regarding the lowest light transmission in the aggregometer was 59.8% ± 24.3% before and 58.3% ± 18.1% after the treatment. The same variables with ristocetin were 66.8% ± 21.6% and 60.8% ± 23.3%, respectively. In vivo effects of losartan on platelet aggregation with ADP and ristocetin were insignificant.  相似文献   
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Aortic dissection is extremely rare in children. Although it usually presents with severe chest pain, atypical clinical presentations mimicking various illnesses may cause misdiagnosis. In this report, the case of a 14‐year‐old boy with symptoms suggestive of acute abdomen, which was finally diagnosed as aortic dissection, is discussed.  相似文献   
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While the samples and data from the Pima Indians of the Gila River Indian Community have been included in many international HLA workshops and conferences and have been the focus of numerous population reports and the source of novel alleles at the classical HLA loci, they have not been studied for the non-classical loci. In order to expand our HLA-disease association studies, we typed over 300 whole genome sequences from full Pima heritage members, controlled for first degree relationship, and employed recently developed computer algorithms to resolve HLA alleles. Both classical—HLA-A, -B, and -C— and non-classical— HLA-E, -F, -G, -J, -L, -W, -Y, -DPA2, -DPB2, -DMA, -DMB, -DOA, -DRB2, -DRB9, TAP1— loci were typed at the 4-field level of resolution. We present allele and selected haplotype frequencies, test the genotype distributions for population structure, discuss the issues that are created for tests of Hardy-Weinberg equilibrium over the four sample spaces of high resolution HLA typing, and address the implications for the evolution of non-classical pseudogenes that are no longer expressed in a phenotype subject to natural selection.  相似文献   
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Objective:To determine the total oxidant status (TOS), total antioxidant status (TAS), and the 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels and their interrelationship in the saliva of children undergoing fixed orthodontic therapy.Materials and Methods:Thirty children were randomly divided into three groups. The attachments were bonded to all of the teeth using three different orthodontic composites: Transbond XT, Kurasper F, and GrenGloo. The salivary levels of TOS, TAS, and 8-OHdG were determined three times, as follows: before treatment (T1) and at 1 month (T2) and 3 months (T3) following appliance placement. All data were statistically analyzed.Results:There were no significant differences in TOS, TAS, and 8-OHdG within the same time periods among the three different orthodontic composites (P > .05). TAS in all composite groups decreased over time. These decreases were found to be significant for Kurasper F and GrenGloo at the T1–T3 and T2–T3 time periods (P < .05). In all composite groups 8-OHdG decreased between T1 and T2 (P < .05). However, 8-OHdG in all composite groups increased from T2 to T3. These differences in 8-OHdG were significant in Kurasper F and GrenGloo (P < .05).Conclusions:Fixed orthodontic appliances bonded with the tested composites did not increase the cytotoxicity markers in saliva.  相似文献   
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Platelets have the capacity to release mediators with potent inflammatory or anaphylactic properties. Platelet factor-4 (PF4) and beta-thromboglobulin (BTG) are two of these mediators. On the other hand, plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) are two important mediators of fibrinolysis. Both mediators are secreted mainly by vascular endothelium. Plasma levels of PF4, BTG, PAI-1, and tPA may show changes in chronic inflammatory diseases such as asthma. This study examined the role of thrombocytes and the function of the endothelium in asthmatic patients during an attack and during a stable phase. Eighteen patients with known allergic asthma who came to our emergency department with an asthma attack and 14 control subjects were included in the study. Blood samples were taken after starting therapy with salbutamol inhalation. Lung function tests were performed after receiving the first emergency therapy for asthma. Plasma levels of PF4, BTG, PAI-1, tPA were determined before starting steroid therapy and after receiving 1 week of steroid therapy. Plasma levels of PF4 among patients with an asthma attack were significantly higher than those of controls (150.5+/-8.92 IU/mL vs. 92.5+/-7.63 IU/mL, p<0.001). A further increase in plasma PF4 levels was detected after steroid therapy (163.5+/-9.16 IU/mL). Plasma BTG levels of patients on admission were not statistically different from those in the control group (140.4+/-6.34 IU/mL vs. 152.2+/-8.71 IU/mL). An increase was detected after therapy (171.6+/-7.27 IU/mL) and post-treatment plasma levels were statistically meaningful versus the controls. Plasma levels of tPA and PAI were statistically higher than those in controls in asthmatic patients on admission (6.01+/-2.72 vs. 5.4+/-2.3 ng/mL for tPA and 75.2+/-27.2 ng/mL vs. 32.7+/-14.3 ng/mL for PAI-1). Further increases were detected in two parameters after 1 week of therapy with steroids (tPA levels were 6.85+/-2.96 ng/mL and PAI-1 levels were 83.5+/-29.6 ng/mL). There seems to be an increased activity of platelets during an asthma attack. Elevated PAI-1 and tPA levels may also indicate the activated endothelium in asthma. Increases of plasma levels of PAI-1 and tPA after steroid therapy need further investigation because elevated PAI-1 levels enhance airway remodeling.  相似文献   
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In the literature, there have been no studies showing clear results on how radio‐contrast pharmaceuticals would affect intact disc tissue cells. In this context, it was aimed to evaluate the effects of iopromide and gadoxetic acid, frequently used in the discography, on intact lumbar disc tissue in pharmaco‐molecular and histopathological level. Primary cell cultures were prepared from the healthy disc tissue of the patients operated in the neurosurgery clinic. Except for the control group, the cultures were incubated with the indicated radio‐contrast agents. Cell viability, toxicity and proliferation indices were tested at specific time intervals. The cell viability was quantitatively analysed. It was also visually rechecked under a fluorescence microscope with acridine orange/propidium iodide staining. Simultaneously, cell surface morphology was analysed with an inverted light microscope, while haematoxylin and eosin (H&E) staining methodology was used in the histopathological evaluations. The obtained data were evaluated statistically. Unlike the literature, iopromide or gadoxetic acid did not have any adverse effects on the cell viability, proliferation and toxicity (P < 0.05). Although this study reveals that radio‐contrast pharmaceuticals used in the discography, often used in neurosurgical practice, can be safely used, it should be remembered that this study was performed in an in vitro environment.  相似文献   
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