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51.
Rotavirus strain surveillance is being conducted in many countries before and after introduction of newly licensed vaccines to assess the impact of the vaccines on rotavirus strains. Here we describe a strain surveillance study in the Budapest area of Hungary (2003–2006) based on RNA profile analysis, genotyping by multiplex PCR and nucleotide sequencing. Among 1,983 G‐typed rotaviruses we identified G1 (22%), G2 (4.8%), G3 (3.5%), G4 (18.5%), G6 (1.1%), G8 (<0.1%, n = 1), G9 (42%), and G12 (3.4%) specificities. Information on P genotype incidence was determined for a subset of samples (n = 814). In addition to the globally important strains, a variety of uncommon antigen combinations were also found, for example, P[9],G3; P[14],G6; or P[14],G8. Sequence and phylogenetic analysis of the VP7, VP4, VP6, and NSP4 genes of selected strains with uncommon antigen combinations demonstrated high similarity with certain bovine, porcine, feline, equine, and lapine rotaviruses, respectively. Continued surveillance is needed to assess the role of animal rotaviruses in human diseases. J. Med. Virol. 81:362–370, 2009. © 2008 Wiley‐Liss, Inc.  相似文献   
52.
Oxidative and nitrosative stress play an important role in the development of endothelial vascular dysfunction during early atherosclerosis. Oxidative stress activates the nuclear enzyme poly(ADP-ribose) polymerase (PARP) in endothelial cells. In patients with atherosclerosis the level of oxidized LDL in the plasma is elevated. In oxidized LDL various oxysterols have been identified, such as 7-ketocholesterol (7K). 7K has been shown to induce PARP activation in microglial cells. The aim of the current study was to clarify the effects of 7K on the activity of endothelial PARP and on the endothelium-dependent relaxant function of blood vessels. We treated human umbilical vein endothelial (HUVEC) cells with 2-16 microg/ml 7K as well as vascular rings harvested from BALB/c mouse thoracic aorta with 90 microg/ml 7K for 2 h. A group of mice was treated with 7K subcutaneously for 1 week (10 mg/kg/day). We also conducted in vitro and in vivo experiments using pretreatment with buthionine sulphoximine (BSO), a glutathione-lowering agent. The activity of PARP was calculated by measurement of tritiated NAD incorporation. The activity of PARP increased significantly in 7K-treated HUVEC cells. After BSO pretreatment, this increase was higher. Isolated vascular rings demonstrated no change in endothelium-dependent relaxant function after 2 h of incubation with 7K, even after BSO pretreatment. In vivo treatment with 7K for 1 week had no effect on the relaxant function. Our experimental results suggest that although 7-ketocholesterol can activate PARP enzyme in endothelial cells, it is not sufficient on its own to cause impairment in the endothelium-dependent vascular reactivity.  相似文献   
53.
Patient‐based measures of subjective health status are increasingly used as outcome measures in interventional trials. We aimed to determine the variability and predictors of subjective health ratings in a possible target group for future interventions: the spinocerebellar ataxias (SCAs). A consecutive sample of 526 patients with otherwise unexplained progressive ataxia and genetic diagnoses of SCA1 (117), SCA2 (163), SCA3 (139), and SCA6 (107) were enrolled at 18 European referral centers. Subjective health status was assessed with a generic measure of health related quality of life, the EQ‐5D (Euroqol) questionnaire. In addition, we performed a neurological examination and a screening questionnaire for affective disorders (patient health questionnaire). Patient‐reported health status was compromised in patients of all genotypes (EQ‐5D visual analogue scale (EQ‐VAS) mean 61.45 ± 20.8). Specifically, problems were reported in the dimensions of mobility (86.9% of patients), usual activities (68%), pain/discomfort (49.4%), depression/anxiety (46.4%), and self care (38.2%). Multivariate analysis revealed three independent predictors of subjective health status: ataxia severity, extent of noncerebellar involvement, and the presence of depressive syndrome. This model explained 30.5% of EQ‐VAS variance in the whole sample and might be extrapolated to other SCA genotypes. © 2010 Movement Disorder Society  相似文献   
54.
55.
Previous studies have suggested that both angiotensin II type-1 receptor (AT1R) 1166C and methylenetetrahydrofolate reductase (MTHFR) 677T variants can have disadvantageous effects on the small-vessel circulation under certain conditions. The purpose of this study was to analyze the possible consequences of the simultaneous distribution of these two genetic variants in different types of ischemic stroke. The genetic and clinical data on 357 ischemic stroke patients and 263 control subjects were analyzed by using univariate and logistic statistical approaches. Neither the MTHFR 677T nor the AT1R 1166C genetic variant alone conferred the risk of any subtype of ischemic stroke. The combination of the homozygous MTHFR 677TT genotype and at least one AT1R 1166C allele occurred more frequently in the ischemic stroke patients (8.68%) than in the controls (4.56%, p < 0.05). Specific subclassification of the patients revealed an accumulation of this combination in small-vessel-associated ischemic stroke (12.2%, p < 0.01); multivariate logistic regression analysis of the data confirmed this association, with an odds ratio of 2.66 (95% confidence interval, 1.28-7.89; p < 0.05). These findings suggest that the combination of these two genetic factors can contribute to the development of small-vessel cerebral infarcts. Although the exact mechanism of action is not known, addition of the unfavourable effects on the endothelial function can be presumed.  相似文献   
56.
Ulcerative colitis (UC) is a chronic inflammatory disease of the gastrointestinal tract. The aim of this study was to verify the prevalence rate of the haplotype called TC, determined by combination of two functional alleles of OCTN cation transporter genes (SLC22A4 1672T and SLC22A5 /t-207C combination variants) in ulcerative colitis patients and unrelated healthy controls. The “TC haplotype” has recently been suggested to confer risk for UC. A total of 121 unrelated Hungarian subjects with UC and 110 matched controls were genotyped for the two single nucleotide polymorphisms. The genotypes were determined by using PCR/RFLP assay and direct sequencing. The SLC22A4 1672T allele frequency was 46.7% in the patients with UC and 46.4% in the controls, whereas the SLC22A5 −207C allele occurred in 48.8% of the patients and 51.4% of the controls. The prevalence of the TC haplotype was 19% in the patient group and 22.7% in controls. Since there was no accumulation of the TC haplotype in the patient group, our observation suggests that carrying the TC haplotype is not associated with a higher risk for UC in the Hungarian population.  相似文献   
57.
AIM: To investigate the frequency of the common NOD2/CARD15 susceptibility variants and two functional polymorphisms of OCTN cation transporter genes in Hungarian pediatric patients with Crohn's disease (CD). METHODS: A cohort of 19 unrelated pediatric and 55 unrelated adult patients with Crohn's disease and 49 healthy controls were studied. Genotyping of the three common CD-associated CARD15 variants (Arg702Trp, Gly908Arg and 1007finsC changes) with the SLC22A4 1672C-->T, and SLC22A5 -207G-->C mutations was performed by direct sequencing of the specific regions of these genes. RESULTS: At least one CARD15 mutation was present in 52.6% of the children and in 34.5% of the adults compared to 14.3% in controls. Surprisingly, strongly different mutation profile was detected in the pediatric versus adult patients. While the G908R and 1007finsC variants were 18.4% and 21.1% in the pediatric group, they were 1.82% and 11.8% in the adults, and were 1.02% and 3.06% in the controls, respectively. The R702W allele was increased approximately two-fold in the adult subjects, while in the pediatric group it was only approximately 64% of the controls (9.09% in the adults, 2.63% in pediatric patients, and 4.08% in the controls). No accumulation of the OCTN variants was observed in any patient group versus the controls. CONCLUSION: The frequency of the NOD2/CARD15 susceptibility variants in the Hungarian pediatric CD population is high and the profile differs from the adult CD patients, whereas the results for SLC22A4 and SLC22A5 mutation screening do not confirm the assumption that the carriage of these genotypes means an obligatory susceptibility to CD.  相似文献   
58.
Aims:  To investigate the effects of antigen retrieval and primary antibody selection on specificity and sensitivity of CD117 immunohistochemistry.
Methods and results:  A survey and literature review were performed to determine the most commonly used CD117 antibodies. Of six such antibodies, three (Neomarkers polyclonal RB-1518, Novocastra monoclonal T595 and Santa Cruz polyclonal C19) were rejected as only suboptimal immunoreactivity was produced despite the use of various immunohistochemical protocols. Immunohistochemistry using the three remaining antibodies (Cell Marque polyclonal CMC766, Dako polyclonal A4502 and Epitomics monoclonal YR145) was performed, with and without (for Dako and Epitomics antibodies) antigen retrieval, on 32 gastrointestinal stromal tumours (GISTs) and on 139 neoplasms (comprising 24 neoplasm types) that are differential diagnoses for GIST and/or have been reported to express CD117. Antigen retrieval generally increased the sensitivity but did not alter the specificity of immunoreactivity with the three antibodies. The different antibodies showed variations in sensitivity, but did not stain different spectrums of neoplasm type. A small number of neoplasms showed scattered nuclear immunopositivity (particularly seen without antigen retrieval), which was regarded as representing cross-reactivity.
Conclusions:  Antigen retrieval and changing between the three antibodies tested affect sensitivity but not specificity of CD117 immunohistochemistry. Antigen retrieval does not produce false-positive CD117 immunostaining.  相似文献   
59.
Rotavirus-associated enteritis has been reported in pheasants, but there is no information on the genetic/antigenic features of pheasant rotaviruses. In this study, we sequenced the VP7-encoding genome segment of three pheasant rotavirus strains detected during 2008 in Hungary. The full-length genome segment was 1,070 bp long, while the open reading frame was predicted to encode a 330-aa-long protein. The nucleotide sequence identities among the three pheasant rotavirus strains were high (≥94%), whereas the range of nucleotide sequence identities to other avian and mammalian rotavirus VP7 genes fell between 68 and 73% and between 60 and 66%, respectively. Our findings indicate that these Hungarian pheasant rotaviruses need to be considered representatives of a new VP7 genotype specificity, designated G23.  相似文献   
60.
6-N-Trimethyl-[d9]-L-lysine (dTML), the labeled form of a mammalian carnitine precursor, was administered to two groups of premature infants. Although the urinary output of dTML significantly increased in the low-dose-treated group (100 micromol/day), this amount did not affect the urinary output or plasma levels of carnitine and carnitine esters. In the second group of infants, after administration of 500 micromol dTML the plasma-free carnitine concentration increased (from 9.95 +/- 0.63 to 12.9 +/- 0.87 nmol/ml, p > 0.05) with a significant increase in the urinary excretion of free carnitine on the day of dTML administration and on the posttreatment day (from 4.79 +/- 1.36 to 9.85 +/- 1.18 and to 17.5 +/- 2.31 micromol/day, respectively). Analysis of urine using fast atom bombardment mass spectrometry (FAB-MS) revealed only the presence of the dTML in the urine of the newborns; no change was detected in the relative abundance of any other carnitine precursor. Surprisingly, in the second group, which received the higher dose of dTML supplement, only the signal intensity of the unlabeled carnitine increased after dTML administration; no new peak appeared in the urine that would correspond to the de novo synthesized carnitine containing the stable isotope-labeled trimethyl group of dTML. Thus, the FAB-MS analysis clearly demonstrated that contrary to the likely prediction, the 270% extra free carnitine output was a consequence of a dose-dependent dTML-induced depletion of the free carnitine reserves from the newborns. The absence of the incorporation of the label from dTML into carnitine strongly suggests that circulating TML is not the precursor of carnitine in premature infants.  相似文献   
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