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91.
Self-help support groups for medical students represent one strategy for dealing with the emotional stresses of medical training and the diminished human sensitivity of students that often accompanies that experience. Support groups at the Albert Einstein College of Medicine were evaluated by 26 students who completed a nine-part questionnaire. The respondents indicated that they were primarily drawn to these groups because of a desire for social affiliation and an opportunity to express their feelings in a "safe" environment. Members shared in the leadership responsibilities of the group and dealt with external personal problems of the students rather than with the internal group dynamics. The gains derived from participation in these groups included opportunities for nonprofessional contact with faculty members, getting help and support from fellow students, and participation in stimulating discussions about the medical field. Students rated the groups as "meaningful" and expressed a desire for more frequent meetings.  相似文献   
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The replication of RSV in unimmunized cotton rats was evaluated by quantitating the amount of infectious virus in the lung and the number of RSV infected cells in a histopathological section of lung by in situ hybridization. RSV infected cells were detected only in alveoli and bronchioles and constituted only a small minority of the cell population. The temporal patterns of rise to the peak number of infected cells (day 4) and the peak titer of infectious virus (day 3) were similar. The clearance of both infected cells and infectious virus was nearly complete by day 7. In animals previously immunized with purified RSV glycoproteins or formalin-inactivated RSV there also was a good correlation between the number of infected cells detected by in situ hybridization and the amount of infectious virus recovered. It was previously demonstrated that cotton rats immunized with formalin-inactivated vaccine developed enhanced pulmonary histopathology following challenge with RSV. In such animals, there was approximately a 90% reduction in the number of infected cells compared to control unimmunized, RSV-challenged animals. Formalin-inactivated RSV vaccine-enhanced lung histopathology developed despite the effective elimination of virus and virus-infected cells suggesting that the enhanced pathology is the result of an exaggeration of normal immune mechanisms involved in clearance of virus infection, an aberrant immune response during infection, or both.  相似文献   
94.
Janet Lee, MS; Lisa A. Croen, PhD; Kendall H. Backstrand, BA; Cathleen K. Yoshida, MS; Louis H. Henning, BA; Camilla Lindan, MD; Donna M. Ferriero, MD; Heather J. Fullerton, MD; A. J. Barkovich, MD; Yvonne W. Wu, MD, MPH

JAMA. 2005;293:723-729.

Context  Perinatal arterial ischemic stroke (PAS) is a common cause of hemiplegic cerebral palsy. Risk factors for this condition have not been clearly defined.

Objective  To determine maternal and infant characteristics associated with PAS.

Design, Setting, and Patients  Case-control study nested within the cohort of all 199 176 infants born from 1997 through 2002 in the Kaiser Permanente Medical Care Program, a managed care organization providing care for more than 3 million residents of northern California. Case patients were confirmed by review of brain imaging and medical records (n = 40). Three controls per case were randomly selected from the study population.

Main Outcome Measure  Association of maternal and infant complications with risk of PAS.

Results  The population prevalence of PAS was 20 per 100 000 live births. The majority (85%) of infants with PAS were delivered at term. The following prepartum and intrapartum factors were more common among case than control infants: primiparity (73% vs 44%, P = .002), fetal heart rate abnormality (46% vs 14%, P<.001), emergency cesarean delivery (35% vs 13%, P = .002), chorioamnionitis (27% vs 11%, P = .03), prolonged rupture of membranes (26% vs 7%, P = .002), prolonged second stage of labor (25% vs 4%, P<.001), vacuum extraction (24% vs 11%, P = .04), cord abnormality (22% vs 6%, P = .01), preeclampsia (19% vs 5%, P = .01), and oligohydramnios (14% vs 3%, P = .01). Risk factors independently associated with PAS on multivariate analysis were history of infertility (odds ratio [OR], 7.5; 95% confidence interval [CI], 1.3-45.0), preeclampsia (OR, 5.3; 95% CI, 1.3-22.0), prolonged rupture of membranes (OR, 3.8; 95% CI, 1.1-12.8), and chorioamnionitis (OR, 3.4; 95% CI, 1.1-10.5). The rate of PAS increased dramatically when multiple risk factors were present.

Conclusions  Perinatal arterial ischemic stroke in infants is associated with several independent maternal risk factors. How these complications, along with their potential effects on the placenta and fetus, may play a role in causing perinatal stroke deserves further study.

  相似文献   

95.
A H Lebovits  L G Croen  R Z Goetzel 《Cancer》1984,54(6):1124-1129
A questionnaire evaluating attitudes towards cancer (the Cancer Attitudes Questionnaire) was constructed to compare the attitudes of first-year medical students before and after taking a clinical oncology program with those of students who did not participate in the program. A factor and reliability analysis revealed five underlying factors that explained 42% of the variance and reliabilities ranging from 0.55 to 0.79. An analysis of covariance revealed that students who participated in the clinical oncology program were more positively predisposed toward the outpatient functioning of cancer patients (P less than 0.04) at the conclusion of the year than students who did not take the course; the participating students were also somewhat less pessimistic toward the disease (P less than 0.07). Women (regardless of whether they had taken the course) assigned significantly greater importance to the patient's and family's attitudes in relation to outcome of disease (P = 0.03) than did male students. It appears that an early medical educational oncology experience emphasizing contact with ambulatory cancer patients can appreciably alter the attitudes of first-year medical students towards cancer.  相似文献   
96.
OBJECTIVES: To investigate the association between cerebral palsy (CP) and congenital abnormalities among children with very low, low, and normal birth weight.Study design: A population-based, case-control study among the cohort of 155,636 live births delivered between 1983 and 1985 in 4 California counties. Children with moderate or severe congenital CP (n = 192) diagnosed by age 3 were identified from 2 California State service agencies, and 551 control children were randomly sampled from birth certificate files. Information on congenital abnormalities diagnosed by the age of 1 year was obtained from the California Birth Defects Monitoring Program registry. Odds ratios (OR) and 95% CIs were calculated to estimate risk for CP associated with congenital abnormalities. RESULTS: Among singletons, congenital abnormalities were present in 33 (19.2%) children with CP and 21 (4.3%) control children (OR = 5.2, 95% CI 2.8-9.7). For each birth weight group, the percent of children with congenital abnormalities among children with CP exceeded that among control children. Structural abnormalities of the central nervous system were more common among children with CP (OR = 16.2, 95% CI 5.8-49.3) than control children. In contrast, the percent of children with non-central nervous system abnormalities only was similar between case patients and control subjects. CONCLUSION: These findings provide further evidence that factors operating in the prenatal period contribute significantly to the etiology of CP.  相似文献   
97.
Holoprosencephaly is a developmental field defect manifested by a spectrum of abnormalities of the forebrain and midface. Approximately 50% of holoprosencephaly cases are associated with a cytogenetic abnormality or a monogenic syndrome. Suggested risk factors for the remaining 50% of cases have been described in case reports, but have not been confirmed in systematically conducted studies. We report the results of a population-based case-control study of holoprosencephaly. Live births, fetal deaths, and terminations with a diagnosis of cytogenetically normal holoprosencephaly were identified by the California Birth Defects Monitoring Program. Telephone interviews were conducted with the mothers of 58 cases and 107 live born, nonmalformed controls. Women were questioned about their health and reproductive histories, family demographics, and exposures occurring during their pregnancies. Among nonsyndromic cases, increased risks were observed for females (OR=1.8, 95% C.I. 0.9-3.9), foreign-born vs. U.S. or Mexico-born women (OR=3.1, 95% C.I. 1.1-8.6), and women with early menarche (OR=2.3, 95% C.I. 0.9-5.7). Maternal periconceptional exposures associated with increased risks for nonsyndromic holoprosencephaly included alcohol consumption (OR=2.0, 95% C.I. 0.9-4.5), cigarette smoking (OR=4.1, 95% C.I. 1.4-12.0), and combined alcohol and smoking (OR=5.4, 95% C.I. 1.4-20.0), insulin-dependent diabetes (OR=10.2, 95% C.I. 1.9-39.4), medications for respiratory illnesses (OR=2.3, 95% C.I. 0.9-6.0), and salicylate-containing medications (OR=2.5, 95% C.I. 0.8-7.9). These findings are consistent with risk factors identified in some previous reports, and identify several new potential risk factors that require confirmation in future studies.  相似文献   
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100.
The cause of perinatal arterial ischemic stroke is unknown in most cases. We explored whether genetic polymorphisms modify the risk of perinatal arterial ischemic stroke. In a population-based case-control study of 1997-2002 births at Kaiser Permanente Northern California, we identified 13 white infants with perinatal arterial ischemic stroke. Control subjects included 86 randomly selected white infants. We genotyped polymorphisms in nine genes involved in inflammation, thrombosis, or lipid metabolism previously linked with stroke, and compared genotype frequencies in case and control individuals. We tested several polymorphisms: tumor necrosis factor-α ?308, interleukin-6, lymphotoxin A, factor V Leiden, methyltetrahydrofolate reductase 1298 and 667, prothrombin 20210, and apolipoprotein E ε2 and ε4 alleles. Patients with perinatal arterial ischemic stroke were more likely than control subjects to demonstrate at least one apolipoprotein E ε4 allele (54% vs 25%, P = 0.03). More patients with perinatal arterial ischemic stroke carried two ε4 alleles than did control subjects (15% vs 2%, P = 0.09), although this finding lacked statistical significance. Proinflammatory and prothrombotic polymorphisms were not associated with perinatal arterial ischemic stroke. The apolipoprotein E polymorphism may confer genetic susceptibility for perinatal arterial ischemic stroke. Larger population-based studies are required to confirm this finding.  相似文献   
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