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91.
Increasing industrial activity in the European Arctic has raised concerns of the potential anthropogenic impact of chemicals on this polar marine ecosystem. For the past 20 years or so, biomarkers have been developed to provide early-warning signals of detrimental impacts of chemicals on the marine ecosystem, however, most biomarker methods have been established for organisms living in temperate rather than polar waters. Little is known about biomarker responses in organisms living within the temperature range of -1.88 to +5 degrees C. In this study, established biomarkers from temperate studies were tested on the Arctic spider crab Hyas araneus to validate their use in polar ecosystems. H. araneus is common in Svalbard fjord (Norway), although it is a temperate water species occurring from northern Spain to Svalbard at depths from 10 to 1200 m. In this paper, the effects of oil were investigated at 2 degrees C via two routes: (i) injection and (ii) contaminated sediment. After 2 weeks of exposure, heart rate, oxygen consumption and total oxyradical scavenging capacity (TOSC) were measured in the same individuals. In both methods of contaminant exposure, heart rate showed a significant increase compared with the control (P < 0.0001, n = 7); mean heart rate values (+/- S.D.) of H. araneus were 49.06 (+/- 13.72), 57.56 (+/- 7.28) and 63.30 (+/- 6.57) beats per minute in control, injected and sediment-treated groups, respectively. Respiration of H. araneus was not affected significantly by either oil treatment (P > 0.05), but two individuals (n = 8) showed a marked increase in oxygen uptake in the sediment-exposed group. The basal oxygen consumption of control H. araneus was lower (0.025 mg O(2) g wet wt.(-1) h(-1)) than reported for H. araneus living in temperate water. Although TOSC of H. araneus was not affected significantly by either exposure treatment (P > 0.05) the mean TOSC value in the sediment-exposed group was lower than the control, indicating some saturation of the oxyradical scavenging system. Results indicate that although low temperature appears to be the main factor reducing the bioavailability of polycyclic-aromatic hydrocarbons, the relatively low metabolic rate of Arctic H. araneus is also implicated in decreased uptake and metabolism of oil compounds into reactive oxygen species (ROS).  相似文献   
92.
Objective: To test the effect of changing referral mode to Consultation–Liaison Psychiatry (C–L Psychiatry) by implementing early screening with systematic multidisciplinary management for emotional disorders in noncognitively impaired medical inpatients. Method: A prospective pre- and postintervention controlled study in the internal medicine division of a university hospital. Results: Out of 515 patients admitted to the internal medicine ward during the study period, 176 were included in the study and gave their informed consent (male=63%); 81 in the control group and 95 in the intervention group. Except for the increase in referral rate to the C–L Psychiatry service (4–32%), there were no significant differences between the baseline and intervention periods either in terms of length of stay in the internal medicine ward and of use and costs of medical resources, or in terms of patients' satisfaction as regards attention paid to psychosocial issues during hospitalization. Conclusion: As a result of changing referral mode to C–L Psychiatry, the lack of effect on length of stay and on medical consumption of medically ill inpatients should be considered in the context of the briefness of the hospitalization periods encountered. Furthermore, the change in referral process does not seem to increase patients' perception of the quality of care provided.  相似文献   
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94.
OBJECTIVE: Our aim was to determine whether chorionicity in twin gestations can be diagnosed by use of high-frequency ultrasonography to count the layers of intraamniotic membrane. STUDY DESIGN: This prospective study of 66 twin pregnancies between 13 and 38 weeks' gestation used transabdominal ultrasonography at 10 MHz. The pregnancy was classified as monochorionic when two layers were counted and as dichorionic when three or four layers were counted. The findings of the examiner, who had no other information about chorionicity, were compared with those of the histopathologic examination of the placenta. RESULTS: Ultrasonography allowed chorionicity to be determined correctly in 60 of 63 cases (95%; 100% in the second trimester and 92% in the third). The predictive value for dichorionicity was 100% (48/48) and the sensitivity 94% (48/51). The 12 monochorionic diamniotic pregnancies in which the membrane was visualized were all correctly diagnosed. In a thirteenth case, with severe oligohydramnios, the membrane could not be seen. Two patients were lost to follow-up. In 95% of the cases (63/66) only one examination was required to diagnose chorionicity. Intraobserver variability was 0% (0/26). Interobserver variability, tested by photographs, was 3% (2/65). CONCLUSIONS: This technique should be the first-line method for determining chorionicity in the second and third trimesters because it is the most effective. Its excellent reproducibility may be attributable to the use of high-frequency ultrasonography. (Am J Obstet Gynecol 1996;175:1529-33.)  相似文献   
95.
STUDY OBJECTIVE: To evaluate the clinical assessment of splenic enlargement using specific bedside maneuvers including Traube's space percussion, the splenic percussion sign, Middleton's maneuver, supine palpation, and right lateral decubitus palpation. DESIGN: Quasi-experimental prospective study of cases and controls selected according to the results of abdominal ultrasonographic examinations. SETTING: Selected inpatients of a tertiary care hospital. MAIN RESULTS: Comparing the areas under the receiver operating characteristic curves for each bedside maneuver demonstrated that Traube's space percussion and palpation were significant discriminators (p less than 0.001) of splenic enlargement with respective areas of 0.70 +/- 0.04 and 0.76 +/- 0.04. No one palpation maneuver was superior to another, and right lateral decubitus palpation was not useful when performed after supine palpation. The splenic percussion sign (sensitivity 79%, specificity 46%) was no better than Traube's space percussion (sensitivity 62% and specificity 72%) in assessing splenic enlargement. The palpation maneuvers appeared more sensitive and more specific than Traube's space percussion. Palpation was a significant clinical discriminator when performed on patients who exhibited percussion dullness of Traube's space (area = 0.87 +/- 0.04, p less than 0.0001) but was of little value among those without percussion dullness (area = 0.55 +/- 0.08). Also, palpation was significantly more accurate when performed on lean patients versus obese patients (areas = 0.83 +/- 0.04 versus 0.65 +/- 0.08, p less than 0.05). When a positive bedside examination was defined as positive palpation and positive percussion (concordant-positive), the combined test sensitivity and specificity were 46% and 97% respectively. CONCLUSIONS: The optimal clinical assessment of splenic enlargement includes the percussion of Traube's space. If Traube's space is dull, palpation of the spleen is warranted. This assessment is most accurate in lean patients.  相似文献   
96.
97.

Background

BCG vaccine is considered to have immunoprophylactic potential in leprosy. However controversy exists about the extent of prophylaxis it provides. In view of this, a study was undertaken to see the evolution of disease in established cases of leprosy who were already vaccinated with BCG and to compare it with the cases of leprosy who were not vaccinated with BCG.

Methods

114 newly diagnosed cases of leprosy were studied. Patients were divided into two groups-BCG vaccinated and non-vaccinated. Clinical diagnosis of leprosy was confirmed by bacteriological and histopathological studies in each case. All patients were given standard anti leprosy treatment and were evaluated monthly for a minimum period of one year.

Results

All the cases were males in the age group of 20 to 50 years. 25.4% of cases had received BCG vaccine and 74.6% were not vaccinated for the same. No significant difference was observed in the incidence of different types of leprosy in vaccinated and non-vaccinated groups. 25.9% cases in non-vaccinated group developed lepra reaction as compared to 13.8% in vaccinated group. The incidence of deformities and disabilities in vaccinated group was only 10.3% as against 18.8% in non-vaccinated group. The rate of bacillary clearance appeared faster in vaccinated group.

Conclusions

Although there is no significant difference in the pattern of different types of leprosy in BCG vaccinated and non-vaccinated cases, there is reduction in the incidence of reactions as well as deformities and disabilities in BCG vaccinated cases as compared to non-vaccinated cases.Key Words: BCG Vaccine, Leprosy  相似文献   
98.
99.
The authors describe a simple technique for diagnosis of tricuspid regurgitation. Red blood cells were labeled in vivo with 99mTc and 22 patients were studied with ECG-gated blood-pool imaging of the liver. A single region of interest was manually drawn around the liver and a time-activity curve obtained. The per cent change in liver counts during the cardiac cycle was found to be significantly higher in the 12 patients with tricuspid regurgitation (Group I) (mean, 4.04 +/- 1.6%; range, 1.3-21.4%) compared with the 10 controls (Group II) (mean, 0.35 +/- 0.16%; range, 0.013-1.3%) (p less than 0.05). Using a 1% change in liver counts as the criterion of a positive study, all 12 cases in Group I were diagnosed correctly, but there was one false positive in Group II; thus the sensitivity was 100% and the specificity 90%.  相似文献   
100.
Differential CT diagnosis of extruded nucleus pulposus   总被引:1,自引:0,他引:1  
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