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31.
The possibility of recording changes in electroencephalography potentials following perception of sound was reported several decades ago. The recent expanding research on auditory cortical event-related potentials (AERPs) for assessing sound discrimination abilities in children and infants has indicated that several methodological issues need to be addressed before it can be implemented in clinical practice. Latencies, polarities, and amplitudes of the responses change with gestational age and during infancy. Thus, the maturation of the infant must be considered when designing stimulus paradigms and interpreting the responses. Of healthy newborn infants, only about 80% will show mismatch negativity, the automatic change detection of the auditory stimuli. Currently, the AERP method cannot be applied in clinical practice in the neonatal period, although the findings in healthy newborns at risk for dyslexia are promising. Further research will elucidate the possibility of developing AERPs as a possible early screening method during infancy for later dyslexia or cognitive dysfunction.  相似文献   
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The optimal inhaled oxygen fraction for newborn resuscitation is still not settled. We hypothesized that short-lasting oxygen ventilation after intrauterine asphyxia would not cause arterial or cerebral hyperoxia, and therefore be innocuous. The umbilical cord of fetal sheep was clamped and 10 min later, after delivery, ventilation with air (n = 7) or with 100% oxygen for 3 (n = 6) or 30 min (n = 5), followed by air, was started. Among the 11 lambs given 100% oxygen, oxygen tension (PO2) was 10.7 (1.8-56) kPa [median (range)] in arterial samples taken after 2.5 min of ventilation. In those ventilated with 100% oxygen for 30 min, brain tissue PO2 (PbtO2) increased from less than 0.1 kPa in each lamb to individual maxima of 56 (30-61) kPa, whereas in those given oxygen for just 3 min, PbtO2 peaked at 4.2 (2.9-46) kPa. The maximal PbtO2 in air-ventilated lambs was 2.9 (0.8-5.4) kPa. Heart rate and blood pressure increased equally fast in the three groups. Thus, prolonged ventilation with 100% oxygen caused an increase in PbtO2 of a magnitude previously only reported under hyperbaric conditions. Reducing the time of 100% oxygen ventilation to 3 min did not consistently avert systemic hyperoxia.  相似文献   
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PURPOSE: To estimate the prevalence of pseudoexfoliation syndrome or exfoliation syndrome (ES) in a cross-sectional study and during a long-term follow-up, and to analyse how ES has been inherited in a large pedigree on an isolated population of K?kar island in southern Finland. METHODS: In a population-based study conducted between 1960 and 1962, a comprehensive ophthalmological examination was performed on 595 subjects (85% of the population). From then until 2002, 965 subjects were examined at least once. A pedigree was constructed for all ES-affected subjects according to genealogical studies. The genetic contribution to ES was investigated in this pedigree by segregation analysis and the heritability of the intraocular pressure (IOP) quantitative trait estimated using SOLAR and SAGE software. RESULTS: In the cross-sectional study, the prevalence of ES was 8.1% for 247 subjects over 50 years of age (males 7%, females 9%) and increased to 18.4% for 70 subjects over 70 years of age (males 13%, females 25%). In addition, two females less than 50 years of age were ES-affected. Between 1960 and 2002, 76 (14.3%) of 530 subjects over 50 years of age had ES [23 males (10%) and 53 females (18%)]. Exfoliation glaucoma (EG) was found more often in males (11 patients, 48%) than in females (13 patients, 25%) whereas primary open-angle glaucoma (POAG) was almost as frequent in males (seven patients, 3%) as in females (five patients, 2%). The relative risk (RR) of glaucoma (ES versus no ES) was 11.9 [95% confidence interval (CI) 6.2-22.9] for all the subjects - 14.6 for males (95% CI 6.3-34.0) and 11.8 for females (95% CI 4.4-31.6). Seventy-five pedigrees of 78 ES-affected patients were linked together into one large pedigree with 110 nuclear families. The segregation ratio of ES was 18% (8% for males, 24% for females) when both parents were unaffected, and 16% (9% for males, 27% for females) when at least one parent was affected. The heritability of IOP was estimated to be 30%. CONCLUSION: In this population-based family study, ES is consistent with an autosomal dominant trait with incomplete penetrance, where the penetrance is more reduced in males than in females. However, the presence of ES was a greater risk factor for developing glaucoma in males than in females.  相似文献   
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A genetic analysis of marital migration in Kitee, Finland, is presented. The data are based on 9970 marriages which took place between 1750 and 1877. The results of this analysis are compared with those of previous studies of the population of the Aland Islands, Finland. Analysis of inter-subdivision genetic kinship matrices shows that genetic heterogeneity in Kitee is substantially less than in Aland. This is due primarily to higher rates of migration, both between subdivisions and from outside the population, in Kitee compared to Aland. These differences in migration rates can in turn be attributed to greater geographic isolation in Aland and the contrasting social structures of the two populations. Because of differences in geographic structure and population distribution, geographic distance between subdivisions is a better predictor of inter-subdivision genetic kinship in Kitee than in Aland. The Aland Islands are known to have high frequencies of several otherwise rare genetic diseases; in addition, these diseases are distributed very non-randomly among Aland's subdivisions. The genetic structure results presented here suggest that Kitee should have a less unique distribution of genetic diseases.  相似文献   
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OBJECTIVE: Behavioral experiments show that infants use both prosodic and statistical cues in acquiring language. However, it is not yet clear whether these prosodic and statistical tools are already present at birth. METHODS: We recorded brain responses of sleeping newborns to natural sounds rich in prosody, namely singing and continuous speech, and to two impoverished manipulations of speech. A total of 11 newborns were presented with continuous speech, singing, and degraded speech, while MEG was recorded. RESULTS: We found that a brain response elicited to the prosodically rich singing and continuous natural speech conditions decreased dramatically when the prosody in the speech was impoverished. CONCLUSIONS: We claim that this response is the indicator of the infants' sensitivity to prosodic cues in language, which is already present at birth during natural sleep. SIGNIFICANCE: The indicators of detection of prosody may be crucial in assessing the normal and abnormal cortical function in newborns, especially of those infants at-risk for language problems.  相似文献   
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Barbershops constitute potential sites for community health promotion programs targeting hypertension (HTN) in black men, but such programs have not been evaluated previously. Here we conducted 2 nonrandomized feasibility studies to determine whether an enhanced intervention program of continuous blood pressure (BP) monitoring and peer-based health messaging in a barbershop lowers BP more than standard screening and health education (study 1) and can be implemented by barbers rather than research personnel (study 2). In study 1, we measured changes in HTN treatment and BP in regular barbershop customers with poorly controlled HTN assigned for 8 months to either an enhanced intervention group (n=36) or a contemporaneous comparison group (n=27). Groups were similar at baseline. BP fell by 16+/-3/9+/-2 mm Hg in the enhanced intervention group but was unchanged in the comparison group (P<0.0001, adjusted for age and body mass index). HTN treatment and control increased from 47% to 92% (P<0.001) and 19% to 58% (P<0.001), respectively, in the enhanced intervention group, whereas both remained unchanged in the comparison group. In study 2, barbers were trained to administer the enhanced intervention continuously for 14 months to the entire adult black male clientele (n=321) in 1 shop. Six barbers recorded 8953 BP checks during 11 066 haircuts, thus demonstrating a high degree of intervention fidelity. Furthermore, among 107 regular customers with HTN, treatment and control increased progressively with increasing intervention exposure (P<0.01). Taken together, these data suggest that black-owned barbershops can be transformed into effective HTN detection, referral, and follow-up centers. Further research is warranted.  相似文献   
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