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81.
PURPOSE: To compare chest radiographic findings and circulating B-type natriuretic peptide (BNP) levels as an adjunct to clinical findings in the diagnosis of heart failure in patients presenting with acute dyspnea. METHODS: The diagnostic performance of radiographic evidence of cardiomegaly/redistribution and BNP levels > or =100 pg/mL as indicators of heart failure were assessed in 880 patients presenting with acute dyspnea to the emergency departments of five U.S. and two European teaching hospitals. BNP levels were determined by a rapid, point-of-care device. Two blinded cardiologists reviewed all clinical data and categorized patients as to whether they had acute heart failure (n = 447) or not (n = 433). RESULTS: Three-factor analyses showed that BNP levels > or =100 pg/mL contributed significantly to the prediction of heart failure over each of the radiographic indicators. In a multivariate logistic regression analysis, both BNP levels > or =100 pg/mL (odds ratio [OR] = 12.3; 95% confidence interval [CI]: 7.4 to 20.4) and radiographic findings of cardiomegaly (OR = 2.3; 95% CI: 1.4 to 3.7), cephalization (OR = 6.4; 95% CI: 3.3 to 12.5), and interstitial edema (OR = 7.0; 95% CI: 2.9 to 17.0) added significant, predictive information above historical and clinical predictors of heart failure. CONCLUSION: In patients presenting to the emergency department with acute dyspnea, BNP levels and chest radiographs provide complementary diagnostic information that may be useful in the early evaluation of heart failure.  相似文献   
82.
AIMS: The ESC/ACC redefined myocardial infarction as any amount of necrosis caused by ischaemia. The aim of this study was to describe the management and outcomes using 'real-world' data taking the new definition of acute myocardial infarction into account. METHODS AND RESULTS: A total of 2,151 consecutive patients (76.0% men) with a myocardial infarction were enrolled at 56 centres in France. The median delay to presentation was shorter in patients with ST-segment elevation myocardial infarction (STEMI) vs. non-STEMI (NSTEMI) (4 vs. 7 h, P < 0.0001). STEMI patients were more likely to receive fibrinolysis (28.9 vs. 0.7%, P < 0.0001) or undergo PCI (71.0 vs. 51.6%, P < 0.0001) but less likely to have bypass surgery (3.1 vs. 4.9%, P < 0.05). At discharge, patients with STEMI received more aggressive secondary prevention therapies than those with NSTEMI, which was not supported by differences in disease severity. A total of 1878 patients were followed-up for 1 year: 36.7% of STEMI and 41.5% of NSTEMI patients were rehospitalized (P = 0.05); 16% in both groups were revascularized. In-hospital mortality was similar (4.6 vs. 4.3%), and 1-year mortality was 9.0% in STEMI patients and 11.6% in NSTEMI patients (Log-Rank P = 0.09). Independent correlates of in-hospital mortality were untreated dyslipidaemia, advanced age, diabetes, and low blood pressure. The strongest predictors of 1-year mortality were heart failure and age. Similar predictors were found in STEMI and NSTEMI subgroups. CONCLUSIONS: Despite different management, patients with STEMI and NSTEMI have similar prognoses and independent correlates of outcome. These findings support the new definition of myocardial infarction.  相似文献   
83.
CD8alpha+ and CD8alpha- dendritic cells (DCs) have been considered as independent DC subpopulations both ontogenetically and functionally during recent years. However, it has been demonstrated that both DC subsets can be generated from a single precursor population, supporting the concept that they do not represent separate DC lineages. By using highly purified splenic CD8alpha- DCs, which were injected intravenously and traced by means of an Ly5.1/Ly5.2 transfer system, this study shows that CD8alpha- DCs acquired the phenotypic characteristics of CD8alpha+ DCs, by a differentiation process involving CD8alpha, DEC-205, and CD24 up-regulation, paralleled by the down-regulation of CD11b, F4/80, and CD4. These data demonstrate that CD8alpha+ DCs derive from CD8alpha- DCs, and strongly support that CD8alpha- and CD8alpha+ DCs represent different maturation or differentiation stages of the same DC population. Therefore, CD8alpha+ DCs would represent the last stage of DC differentiation, playing an essential role in the induction of T-cell responses, due to their antigen-presenting potential, cross-priming ability, and capacity to secrete large amounts of key cytokines such as interferon gamma and interleukin-12.  相似文献   
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BACKGROUND: In South Africa, former apartheid laws encouraged rural males seeking employment to migrate to urban areas, moving weekly, monthly or annually between their rural families and urban workplaces. The combination of the migrant labour system and long family separations caused an explosion of serious health consequences, among others sexually transmitted infections (STIs) in the migrant population. OBJECTIVE: To describe some correlates of male migration patterns for the rural women left behind, especially the fear of STIs that this engendered in them and their risk-avoidance behaviour. Setting and subjects. In KwaZulu-Natal, 208 prenatal patients who were partners of oscillating male migrant workers were interviewed to determine their demographic and behavioural characteristics, and their fear of STIs. RESULTS: Thirty-six per cent of the rural women said that they were afraid of contracting STIs from their returning migrant partners. Women who saw their partners infrequently were more fearful of STI transmission, and were less able to have sexual communication. However, almost none of the women protected themselves, while only 8% used condoms, primarily for contraceptive purposes. CONCLUSIONS: These results reflect the gender-based power relationships of South African male migrants and their rural partners, the social and economic dependency of the women on their migrant partners, and the women's social responsibility to bear children. The results point to the need to go beyond interventions that simply seek to modify behaviour without altering the forces that promote risk taking and discourage risk reduction, and the need to develop appropriate interventions to curb STIs and decrease HIV.  相似文献   
87.
BACKGROUND: Early detection of cutaneous melanoma is the most important step to improve prognosis. In recent years objective techniques have been developed to improve diagnostics of pigmented lesions superior to the naked eye. Digital dermoscopy offers several advantages such as independence from the investigator, format ready for teledermatology and image storage, and comparability. SETTING: In a routine setting including three centres in Europe, i.e. Lugano and Locarno in Switzerland, and Dresden in Germany, the usefulness of digital dermoscopy in daily routine has been evaluated. PATIENTS AND METHODS: Digital dermoscopy was performed with the DB-MIPS system in 1308 patients, and 3544 pigmented lesions were evaluated. A total of 466 pigmented lesions were surgically removed and classified by histopathology. Among those 52 melanomas and 299 dysplastic, naevi could be identified. DB-MIPS system evaluated 35 variables of geometrics, colour, colour distribution and texture. Lesion identification is realized by clustering. Another important part of the analysis was to study the decision making, i.e. removal or follow-up of lesions. The tendency to follow-up was defined as the ratio of (number of suspicious lesions-removed lesions)/suspicious lesions. The interventism is defined as the ratio of the number of removed lesions to the number of suspicious lesions. RESULTS: The DB-MIPS system was robust and easy in handling in daily routine. The data analysis and digital imaging were realized in real time. Fifty-two melanomas could be identified including eight in situ melanomas and 33 T1a melanomas (thinner than 1 mm). Sensitivity of digital dermoscopy varied between 90% and 95% between the three centres. Specificity varied between 79.6% and 93.3%. The centres differed in the patient population, the mean diameter of pigmented lesions and decisions. Interventism varied between 36.3% and 76.0%, follow-up varied from 24% to 63%. Higher levels of clinician's false positive were associated with a higher percentage of interventism. CONCLUSIONS: Digital dermoscopy offers advantages for daily routine in detection of early melanoma. Sensitivity and specificity for early melanomas is high and thereby, the experienced dermatologist can be easily supported in daily routine of a pigment lesion clinic to improve diagnostics and hopefully prognosis in cutaneous melanoma.  相似文献   
88.
Self-help groups are lay, mutual support groups in which people who share some long-term existential problems in their lives meet regularly to support each other empathetically These groups can be viewed as supplementary sources of support outside patients' existing social networks As such, it is of importance to be aware of them when planning nursing care The aim of this study was to examine cardiac nurses' preparedness to use self-help groups as a support strategy A qualitative research method was used and 12 registered nurses from two coronary care units were interviewed The findings showed that nurses' knowledge of social support, self-help groups and of patients' social circumstances as well as their attitudes to their own roles as nurses were of importance in their preparedness to use self-help groups as a support strategy Lack of knowledge of social support and self-help groups affected the nurses attitudes towards lay care and was probably the reason for not using self-help groups as a support strategy Most of the nurses were well informed about their patients' social circumstances, they had an explicit family nursing approach and were not at all against further expansion of their nursing role However, there is a need for education in innovative ways of working that respond to and interact with informal support networks if nurses are to be able to contribute to empowerment of their patients  相似文献   
89.
OBJECTIVE: We hypothesized that umbilical vein serum soluble fms-like tyrosine kinase 1 (sFlt1) concentration was augmented in pre-eclampsia. We also explored a possible association between fetal and maternal concentrations of sFlt1. STUDY DESIGN: At cesarean delivery, maternal serum samples from pre-eclamptic (n=38) and uncomplicated (n=32) pregnancies were obtained, as well as umbilical vein serum and amniotic fluid samples. ELISA for human sFlt1, vascular endothelial growth factor (VEGF) and placental growth factor (PlGF) were performed. RESULTS: Median sFlt1 concentrations were elevated in pre-eclampsia compared to uncomplicated pregnancy, in umbilical venous serum (246 and 163 pg/mL, P=0.04), in maternal serum (9932 and 3417 pg/mL, P<0.001), as well as in amniotic fluid (51,040 and 33,490 pg/mL, P=0.03). A positive association between the fetal and maternal serum levels of sFlt1 was found in the pre-eclampsia group. Median PlGF concentration in the maternal serum was significantly lower in the pre-eclampsia group compared to the control group (82 pg/mL and 169 pg/mL, P<0.001). CONCLUSIONS: sFlt1 concentration is elevated in the fetal circulation in pre-eclampsia, but at a much lower level than in the maternal circulation. The results of our study do not support a substantial fetal contribution to the elevated circulating maternal sFlt1 protein concentration in pre-eclampsia.  相似文献   
90.
Individuals vary largely in their salivary flow and composition, and given the importance of saliva on perception of taste, this might influence how the tastant stimuli are perceived. We therefore hypothesise that altering the individual salivary flow rates has an impact on the perceived taste intensity. In this study, we investigated the role of saliva amount on the perceived taste intensity by excluding parotid saliva and adding artificial saliva close to the parotid duct at preset flow rates. Significant decreases in perception with increasing salivary flow rates were observed for citric acid and sodium chloride. This can partially be explained by a dilution effect which is in line with previous studies on detectable concentration differences. However, since the bitterness and sweetness remained unaffected by the salivary flow conditions and the dilution effect was comparable to that of saltiness, further explanation is needed. Furthermore, we investigated whether the suppression of taste intensity in binary mixtures (taste-taste interactions) could possibly be caused by the increased salivary flow rate induced by an additional taste attribute. The results show, however, that suppression of taste intensity in binary mixtures was not affected by the rate of salivation. This was more likely to be explained by psychophysics.  相似文献   
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