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2.
Epidemiologic data on pleural mesothelioma are scarce on regional and occupational time trends, which would monitor the effects of changes in exposure to asbestos. We aim to characterize time trends, regional, socioeconomic, and occupational risk factors for pleural mesothelioma in Sweden in the years from 1961 to 1998. The Swedish Family-Cancer Database was used to identify patients with pleural mesothelioma. Age-standardized incidence rates and standardized incidence ratio (SIR) were calculated for the population in the Database. A total of 1298 male and 233 female pleural mesotheliomas were retrieved. Age-standardized incidence of the disease was highest, and the trend increased in residents of large industrial and shipbuilding cities. In the last follow-up period, the male rate exceeded the female rate about 10-fold. Among male socioeconomic groups, manual workers showed the highest and ever-increasing SIR. No female socioeconomic group was at risk. For men, plumbers and seamen had the highest risk of 4.56 and 2.83, respectively, but the risks appeared to be decreasing for plumbers, whereas no clear trend was noted for seamen, probably because of indirect expose in ships. Farmers showed an SIR of 0.28, indicating that the population at large was at four times higher risk than farmers. The SIRs of many academic/college-educated groups were two to six times higher than those of farmers, suggesting indirect exposure to asbestos in these groups.  相似文献   
3.
STUDY OBJECTIVE: The aim of the study was to determine whether exposure to tetrachloroethylene during the first trimester of pregnancy has harmful effects on pregnancy outcome. DESIGN: The study used record linkage identification of cases and case-control comparison. SETTING: The study involved dry cleaner and laundry workers throughout Finland who had become pregnant during the study period. Controls were age matched but otherwise unselected women giving birth to normal babies in the study period. SUBJECTS: Cases were defined as women who had been treated for spontaneous abortion or had delivered a malformed child. Out of 5700 workers nearly half had been pregnant during the study period. One pregnancy only was randomly selected for study per worker, and the final study population was 247 women with spontaneous abortions and 33 with malformed infants. Three age matched controls were selected for each abortion case and five for each malformation case. MEASUREMENTS AND MAIN RESULTS: Three women out of four had worked in early pregnancy. Exposure information was collected from 1108 women by mailed questionnaires, with a 77% response, and was partly confirmed by biological monitoring data. Exposure to tetrachloroethylene was found to be significantly associated with spontaneous abortions (odds ratio 3.6, p less than 0.05). CONCLUSION: The findings, together with other available data, indicate that exposure of pregnant women to tetrachloroethylene needs to be minimised.  相似文献   
4.
OBJECTIVE: We investigated whether newborns respond differently to novel and deviant sounds during quiet sleep. METHODS: Twelve healthy neonates were presented with a three-stimulus oddball paradigm, consisting of frequent standard (76%), infrequent deviant (12%), and infrequent novel stimuli (12%). The standards and deviants were counterbalanced between the newborns and consisted of 500 and 750 Hz tones with two upper harmonics. The novel stimuli contained animal, human, and mechanical sounds. All stimuli had a duration of 300 ms and the stimulus onset asynchrony was 1s. Evoked magnetic responses during quiet sleep were recorded and averaged offline. RESULTS: Two deflections peaking at 345 and 615 ms after stimulus onset were observed in the evoked responses of most of the newborns. The first deflection was larger to novel and deviant stimuli than to the standard and, furthermore, larger to novel than to deviant stimuli. The second deflection was larger to novel and deviant stimuli than to standards, but did not differ between the novels and deviants. CONCLUSIONS: The two deflections found in the present study reflect different mechanisms of auditory change detection and discriminative processes. SIGNIFICANCE: The early brain indicators of novelty detection may be crucial in assessing the normal and abnormal cortical function in newborns. Further, studying evoked magnetic fields to complex auditory stimulation in healthy newborns is needed for studying the newborns at-risk for cognitive or language problems.  相似文献   
5.
Mother's education and perinatal problems in Finland.   总被引:5,自引:0,他引:5  
This study using nationwide data expands a previous study from one area in Finland. The purpose was to study how perinatal problems (mortality, short gestation, low birthweight and low Apgar scores) vary by mother's social class, which is measured by level of education. Outcomes of all births in the 1987 Medical Birth Register were linked to the 1988 National Education Register with gives the estimated number of years of completed education. In unadjusted analyses, the lowest educational groups (less than 9 years) had the worst results for outcomes other than neonatal mortality. Results in the two highest educational groups (greater than or equal to 13 and 12 years of education) were similar and if anything, better in the second highest group. Excluding twins and adjusting for confounding variables (age, parity, county, urbanization of residence) by logistic regression analysis did not alter the results much. Adjustment for possible mechanisms correlated with social class (marital status, smoking, time of first antenatal visit) decreased the higher occurrence of low birthweight infants in the low educational groups. Reported previous miscarriages were more common in the higher educational groups. Based on the available background characteristics one would expect to have found the usual social gradient in perinatal problems to have persisted between the two highest educational groups. Further studies on factors causing the plateau in the gradient between these groups might be useful.  相似文献   
6.
BACKGROUND: Airway inflammation is a characteristic feature of bronchial asthma. Previous studies have shown an increased local inflammatory activity in the airway mucosa of asthma patients. OBJECTIVES: To analyze the association of asthma with three sensitive markers of systemic inflammation, C-reactive protein, serum amyloid-A (SAA), and plasma fibrinogen. METHODS: A cross-sectional, population-based study including 1,513 Finnish men aged 45 to 74 years, who participated in a chronic disease risk factor survey in 1997. Of the participating men, 97 were classified as asthma patients. The odds ratios of asthma were analyzed by quartile of each inflammation marker. RESULTS: In logistic regression models the age-adjusted odds ratios (second, third, and fourth quartile as compared with the first quartile) of asthma increased gradually with increasing quartile of C-reactive protein (1.28, 1.19, 1.96, P for trend = 0.039), SAA (1.20, 3.00, 3.49, P for trend < 0.001), and fibrinogen (1.22, 1.79, 3.16, P for trend < 0.001). The associations were independent of smoking. Further adjustment for waist-to-hip ratio, a marker of central obesity, and symptoms of chronic bronchitis weakened the observed association, but the increasing trend in the association of SAA and fibrinogen with asthma remained highly significant. CONCLUSIONS: Sensitive markers of systemic inflammation, particularly SAA and fibrinogen, were positively and significantly associated with asthma prevalence. These findings support the hypothesis that not only local, but also systemic, inflammation exist in bronchial asthma.  相似文献   
7.
A 15-year-old boy with a terminal deletion of the short arm of chromosome 4 is described. The patient has a mild clinical phenotype that is incompatible with Wolf-Hirschhorn syndrome. Careful neurological examination including CT scan did not show any signs of Huntington disease. The chromosomal breakpoint was analyzed by means of polymorphic DNA probes localized close to the tentative Huntington (HD) locus. The breakage has occurred between D4S43 and D4S90 loci and thus deletes part of the chromosomal candidate regions for the HD locus. © 1992 Wiley-Liss, Inc.  相似文献   
8.
Paternal occupational lead exposure and congenital malformations.   总被引:5,自引:0,他引:5       下载免费PDF全文
STUDY OBJECTIVE--The aim was to investigate whether occupational exposure to lead in fathers is associated with congenital malformation in their children. DESIGN--The study was a retrospective case-control study, nested within the wives of men biologically monitored for inorganic lead. Information on pregnancy outcome was obtained from medical registers. SUBJECTS--Cases were defined as wives with malformed child during 1973-82. Three age matched controls were selected for each case from the wives who had given birth during 1973-1983. The final study population was 27 cases and 57 controls. MEASUREMENTS AND MAIN RESULTS--Paternal lead exposure was assessed with blood lead measurements and data obtained from a questionnaire. The response rate was 67% among the cases and 76% among the controls. The odds ratio (OR) of congenital malformation for paternal lead exposure was increased (OR 2.4, 95% confidence interval 0.9-6.5), although not reaching statistical significance. The odds ratios varied from 1.9 to 3.2, when adjusted for one potential confounding variable at a time. CONCLUSIONS--Because of the small numbers and low participation, this study offers limited support for the hypothesis that paternal lead exposure is associated with congenital malformation. Further epidemiological studies on the reproductive hazards of paternal lead exposure are needed.  相似文献   
9.
The detection of a change in a face stimulus was studied in an oddball paradigm. Event-related potentials (ERPs) and MEG responses to face stimuli were recorded in four conditions: 1) happy standard, neutral deviant; 2) neutral standard, neutral deviant; 3) inverted happy standard, inverted neutral deviant; 4) inverted neutral standard, inverted neutral deviant. In all conditions, the target was a face with glasses. Neutral deviants elicited a negative deflection (with a maximum around 280 ms) in ERP and MEG responses, an effect similar to auditory mismatch negativity. Face inversion diminished deviance-related negativity, implying an important role of face recognition in the observed effect. Emotional content and larger physical differences between stimuli in conditions 1 and 3 compared to conditions 2 and 4 did not show statistically significant effect on the neutral-deviant-related negativity.  相似文献   
10.
The extent of rehabilitation services is adequate, but little feedback is available on these services and service users. This paper is based on a client feedback survey of physiotherapy services conducted in Spring 2000. The purpose of the paper is to compare patients' perceptions of the physiotherapy instruction they received in a private outpatient facility and in a public physiotherapy facility. The results of the study showed that physiotherapy clients were satisfied with the therapy and instruction they received. They felt they received an adequate amount of instructions and advice. The rehabilitee's strong commitment to care, high motivation and a support network are important to independent rehabilitation in the future. As for the point of contact, the majority of clients in the private physiotherapy facility were gainfully employed while the health centre had almost as many retired clients. Client instruction was not dependent on the point of contact.  相似文献   
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