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Objective
The etiology of recurrent spontaneous abortions (RSA) in chromosomally normal parents is still unexplained. It is unclear whether or not some factors, such as spontaneous abortions (SA), which occur among extended family members can create a predisposition to RSA. Therefore, this study comprises two parts: (a) an epidemiological part, to evaluate the relationship between RSA in 567 couples and the frequency of SA among their first (I), second (II) and third (III) generation relatives, and (b) a genetic part, investigating whether parental and fetal chromosomal status may predispose to the occurrence of RSA.Study design
Couples (567) having one or more SA were analyzed in this retrospective case-control study. The family reproductive history data was collected from their medical charts.Results
The total number of SA found in 567 couples was 1174, and the largest number occurred at 8–10 weeks of gestation. The majority of spouses had normal karyotypes (88.5% and 91%). Of the remainder, 65% of females and 76% of males expressed constitutional chromosomal variation, mostly pericentric inversion of chromosome 9. Cytogenetic analysis of aborted material showed some type of change in 40% of cases. The family reproductive history data indicated that SA among the couples’ I, II and III generation relatives happened with a frequency two to three times higher than that of the general population (55.5, 47.6 and 32.6% for female relatives, and 45.8, 44.1 and 15.1% for male relatives).Conclusion
Positive reproductive family history for SA might be the causal factor for RSA and can also predetermine women that are of greater susceptibility to preterm pregnancy. 相似文献Objective
Sperm parameters, particularly motility, decrease during cryopreservation. Theophylline generally enhances sperm motility. We analyzed effects of theophylline and freezing on sperm motility.Design: Experimental study.Setting: Private IVF lab.Setting: IVF lab of Mehrgan Hospital.Method
22–55 year-old men participated in this study (30 fresh ejaculation and 8 TESE samples). After sperm analysis, we added theophylline (40 mM) to half of our samples as case group to compare motility with the remaining samples as control group. Cryopreservation was performed in two groups. After thawing, motility of both groups was recorded. Furthermore, theophylline (40 mM) was applied to both groups after thawing again.Result
After adding theophylline, sperm motility improved significantly in all samples. Sperm motility reduced in control group more than the study group after freeze-thaw procedure (P < 0.002, normal morphology <5%). Sperm motility was not enhanced significantly by re-adding of theophylline to the two groups. Interactions between stages and groups were statistically significant in semen and biopsy samples (p < 0.001).Conclusion
Adding theophylline before freezing can preserve motility of sperms in samples with different parameters and even sperms extracted in testicular biopsy. Theophylline may have protective impact on sperms in freezing procedure. 相似文献Method: Three hundred and eighty newborns with gestational age of less than 34 weeks were included in a multicenter case–control study. Respiratory distress (RD) was scored according to Downes’ scoring system. Polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping.
Result: One hundred and eighty-four neonates showed RDS and 196 did not. Gestational age (GA) was significantly lower in the RDS group compared with the controls. AA genotype and A allele were found more frequently in the RDS group than the controls (96.2% versus 63.8% and 98.1% versus 80.6%, respectively) (p =.0001).
Conclusions: This is the first report of association of SFTPB rs7316 polymorphism with RDS development in Iranian newborns. The current study suggests that GA <28-weeks is the most important factor in predisposition to RDS. Genetic background in terms of SP-B gene might be involved in predisposition to RDS in premature neonates. 相似文献
Phenylketonuria (PKU), one of the most common inborn errors of amino acid metabolism, is caused by mutations in the phenylalanine hydroxylase (PAH) gene (PAH). PKU has wide allelic heterogeneity, and over 600 different disease-causing mutations in PAH have been detected to date. Up to now, there have been no reports on the minihaplotype (VNTR/STR) analysis of PAH locus in the Iranian population. The aims of the present study were to determine PAH mutations and minihaplotypes in Iranian families with PAH deficiency and to investigate the correlation between them. A total of 81 Iranian families with PAH deficiency were examined using PCR-sequencing of all 13 PAH exons and their flanking intron regions to identify sequence variations. Fragment analysis of the PAH minihaplotypes was performed by capillary electrophoresis for 59 families. In our study, 33 different mutations were found accounting for 95% of the total mutant alleles. The majority of these mutations (72%) were distributed across exons 7, 11, 2 and their flanking intronic regions. Mutation c.1066-11G > A was the most common with a frequency of 20.37%. The less frequent mutations, p.Arg261Gln (8%), p.Arg243Ter (7.4%), p.Leu48Ser (7.4%), p.Lys363Asnfs*37 (6.79%), c.969 + 5G > A (6.17%), p.Pro281Leu (5.56), c.168 + 5G > C (5.56), and p.Arg261Ter (4.94) together comprised about 52% of all mutant alleles. In this study, a total of seventeen PAH gene minihaplotypes were detected, six of which associated exclusively with particular mutations. Our findings indicate a broad PAH mutation spectrum in the Iranian population, which is consistent with previous studies reporting a wide range of PAH mutations, most likely due to ethnic heterogeneity. High prevalence of c.1066-11G > A mutation linked to minihaplotype 7/250 among both Iranian and Mediterranean populations is indicative of historical and geographical links between them. Also, strong association between particular mutations and minihaplotypes could be useful for prenatal diagnosis (PND) and preimplantation genetic diagnosis (PGD) in affected families.
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