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421.
We studied the possible etiological factors of isolated primary congenital glaucoma (IPCG) using data from the Hungarian Case-Control Surveillance of Congenital Abnormalities, 1980-2002. The study group consisted of 52 cases with IPCG compared to 52 matched control pairs without any defects, and 22,744 malformed controls with non-ocular defects and 37,837 population controls with no defect. Exposure data and family history were collected (i) prospectively by prenatal logbook and other medical records, (ii) retrospectively through a structured questionnaire completed by mothers, and (iii) from supplementary information obtained by regional nurses visiting the homes of non-respondent mothers. Autosomal recessive inheritance of IPCG was suspected on the basis of sib occurrence and parental consanguinity in 15% of cases. The shorter gestational age (with high proportion of preterm birth), higher birth order, large proportion of births among unmarried women, low socioeconomic status, and high rate of unemployment may be related to Gypsy origin of at least 54% of cases of IPCG. We conclude that the higher incidence of IPCG in the Hungarian Gypsy population is associated with their inbreeding and the possible founder effect of a gene mutation.  相似文献   
422.
Two previous Hungarian intervention trials showed that periconceptional folic acid-containing multivitamin supplementation did not change the total (birth + fetal) prevalence of cases with multiple congenital abnormalities (MCAs). However, two US observational studies found an elevated risk for MCAs in the offspring of women who reported periconceptional use of multivitamins containing folic acid. These conflicting results stimulated us to evaluate the data set of the Hungarian Case-Control Surveillance of Congenital Abnormalities and to check the possible association between the use of periconceptional multivitamin supplementations and the total prevalence of cases with MCAs. Of 1,349 cases with MCA, 69 (5.1%) had mothers who used multivitamins during the second and third month of pregnancy. Of 2,405 matched controls without any defect, 126 (5.2%) had mothers who used multivitamin supplementation in early pregnancy. Of 21,494 malformed controls with isolated congenital abnormalities, 1,052 (4.9%) mothers received supplementation with multivitamins during the critical period of CAs including MCAs. There was no difference in the use of multivitamins among the study groups either in the total data set or at the evaluation of only prospective medically recorded data. Medically recorded folic acid use without any multivitamins in the second and third gestational month showed some protective effect for MCAs. In conclusion, our observational case-control study did not detect a folic acid containing multivitamins during the early pregnancy as a risk factor for MCAs.  相似文献   
423.
We are showing that chlorothiazide, a diuretic, is an ABCG2 substrate. It is a Biopharmaceutics Classification System/Biopharmaceutics Drug Distribution and Classification System (BCS/BDDCS) Class IV drug with low bioavailability. Therefore, we tested if chlorothiazide interacts with major apically located intestinal efflux transporters. Our data show that chlorothiazide is transported by ABCG2 with a Km value of 334.6 μM and does not interact with ABCB1 or ABCC2. The chlorothiazide-ABCG2 interaction results in a vectorial transport in MDCKII-BCRP and Caco-2 cells with efflux ratios of 36 and 8.1 respectively. Inhibition of ABCG2 in Caco-2 cells reduced the efflux ratio to 1.4, suggesting that ABCG2 plays a role in limiting chlorothiazide bioavailability in humans.  相似文献   
424.
Ca(2+)-signaling of human melanoma is in the focus of intensive research since the identification of the role of WNT-signaling in melanomagenesis. Genomic and functional studies pointed to the important role of various Ca(2+) channels in melanoma, but these data were contradictory. In the present study we clearly demonstrate, in a number of different ways including microarray analysis, DNA sequencing and immunocytochemistry, that various human melanoma cell lines and melanoma tissues overexpress ryanodine receptor type 2 (RyR2) and express P2X(7) channel proteins as compared to melanocytes. These channels, although retain some of their usual characteristics and pharmacological properties, display unique features in melanoma cells, including a functional interaction between the two molecules. Unlike P2X(7), RyR2 does not function as a calcium channel. On the other hand, the P2X(7) receptor has an antiapoptotic function in melanoma cells, since ATP-activation suppresses induced apoptosis, while knock down of the gene expression significantly enhances that.  相似文献   
425.

Background  

The Smith–Lemli–Opitz (SLO) syndrome is a multiple congenital anomaly with mental retardation due to a decreased or lack of activity of 7-dehydrocholesterol reductase as a consequence of mutations of the DHCR7 gene. This paper describes a special patient with SLO syndrome. Laboratory examination showed low cholesterol (2.77 mmol/L) and increased 7-dehydrocholesterol level (102 mg/L). Molecular genetic analysis revealed a compound heterozygosity c.964-1G>C/p.G366V (c.G1370T) of the proband. The p.G366V is a novel mutation of the DHCR7 gene with guanine by thymine nucleotide exchange resulting in glycin by valin amino acid exchange in the dehydrocholesterol reductase enzyme. Simvastatin (0.2 mg/kg/day) and cholesterol replacement therapy (150–250 mg/kg/day) led to significant improvement in the patient's laboratory findings (7-dehydrocholesterol, cholesterol) as well as in his behavior and gross motor function.  相似文献   
426.
OBJECTIVES: In a previous study, we showed that maternal influenza in pregnancy gives rise to an increase in some congenital abnormality groups. The aim of this study was to ascertain the relationship between influenza during pregnancy and pregnancy complications, and in addition, delivery outcomes particularly preterm birth and low birth weight in newborns. METHODS: The population-based large control (without any defects) data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities, in which pregnancy complications, gestational age and birth weight are medically recorded, was evaluated. RESULTS: Of 38,151 newborn infants, 1838 (4.8%) had mothers with influenza during pregnancy. The prevalence of pregnancy complications showed no difference between mothers with or without influenza during the study pregnancy. Mothers with influenza in pregnancy had a somewhat higher gestational age (0.1 week) and a lower proportion of preterm births (8.0% vs. 9.2%). These findings were reflected in the mean birth weight (+37 g) and lower proportion of low birth weight newborns (4.7% vs. 5.1%); these differences were explained by confounders. CONCLUSION: Maternal influenza during pregnancy does not increase the prevalence of pregnancy complications and unsuccessful delivery outcomes.  相似文献   
427.
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