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51.
BackgroundSurgical resection margins (RM), axillary nodal involvement and lymph node ratio (LNR) determine loco-regional control (LRC) in breast cancer management. Late presentation precludes breast conservation therefore surgical option is usually mastectomy and adjuvant chemoradiation minimize loco-regional recurrence (LRR).ObjectiveWe investigated the prognostic role of lymph nodes positive for malignancy (pN), LNR and RM on LRR of breast cancer in a tertiary hospital in Ibadan, Nigeria.MethodsLongitudinal cohort study of 225 females with breast carcinoma managed and followed up for 5-years with end point of LRR or not. Chi-square test and logistic regression analysis were used to evaluate the interaction of resection margin and proportion of metastatic lymph nodes with LRR. The receiver-operator curve was plotted to determine the proportion of metastatic lymph nodes which predicted LRR.ResultsNinety-nine percent had modified radical mastectomy and 163 (72.4%) had negative resection margins. A mean of 11 axillary lymph nodes were harvested at surgery. The age, positive resection margin and number of harvested nodes with malignant cells are associated with LRR. The overall 5-year LRR rate was 16%.ConclusionLRR is dependent on lymph node involvement as well as and tumor aggressiveness.  相似文献   
52.
The reduction in body mass index standard deviation score (BMI‐SDS) associated with improvement in biomarkers relating to metabolic health in obese children is unknown. We aimed to establish the change in BMI‐SDS associated with improved inflammation, liver function, and insulin resistance to inform clinical guidelines for pediatric weight management interventions and to assess the efficacy of future trials. A large‐scale systematic review was conducted to identify relevant studies. Studies of children with a diagnosis of obesity according to defined BMI thresholds, participating in lifestyle interventions to reduce obesity, were included. Studies must have reported baseline (pre‐) and postintervention (or change of) BMI‐SDS and either fasting glucose, homeostatic model of insulin resistance (HOMA‐IR), alanine aminotransferase (ALT), C‐reactive protein (CRP), or interleukin‐6 (IL‐6). A series of meta‐regressions were conducted to establish links between BMI‐SDS change scores and change in metabolic markers of health. Sixty‐eight articles were identified. From the meta‐regression analyses, across all study subsets, greater mean falls in all four parameters, (HOMA‐IR, Glucose, ALT, and CRP) were observed with greater mean loss of BMI‐SDS, but the trends were only statistically significant for HOMA‐IR and CRP (P = .003; P = .021). However, we could not find minimum changes in BMI‐SDS that would ensure a fall in these outcomes. At this time, we are unable to recommend a definitive value of BMI‐SDS reduction needed to improve the markers of metabolic health. Future trials should aim to report additional indices of derived BMI values, which may better reflect changes in actual adiposity.  相似文献   
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54.
Abstract— Twelve test cavities were filled with Adaptic Radiopaque by die author, varying the spatulation times from 5 s to 60 s at 5-s intervals but using the same mixing technique. Fillings spatulated for less than 20 s appeared inhornogeneous on radiographs. 2) Twenty-eight dentists produced 84 test fillings determining themselves their spatulation time and applying their own mixing technique. Spatulation times varied! froira 10 to 35 s. The fillings were radiographed under standardized conditions. Twenty-five were classified as radio graphically homogeneous, 35 as partly iniiomogeneous, and 24 as inhomogeneous. Short spatulation times were correlated with a high frequency ofinhomogeiieous fillings. Only 15% of fillings spatula ted for less than 30 s were radiographically homogeneous. The observed inhomogeneities imply a risk of false positive diagnoses of secondary carious lesions.  相似文献   
55.
Abstract — The CEJ on radiographs is often used as a reference point in the assessment of alveolar bone loss. The aim of the present study was to test the stability of the radiographic CEJ ("RCEJ") in relation to the alveolar west under varying angulations of the central X-ray beam. In an experimental model four types of extracted teeth were radicrgraphed al 0° and 20° vertical angulation and at 15 horizontal angulations varying from a 17.5° mesial view to a 17.5° distal view. The buccal alveolar bone margin was simulated by a steel needle. RCEJ-"crest" distances were read at a × 10 magnification. Changing the vertical angutation from 0° to 20° reduced the RCEJ-"crest" distances far all tooth types (range ofaverage reduction 2.2–4.1 mm). HorizontaE angulations without concomitant vertical angularion had a significant effect but where without clinical significance. Horizontal anglslations in combination with a 20° vertical angulation bad a considerable influence; in a mesial view, mesial RCEJ-"crest" distances decreas-ed and distal ones increased, and vice wna in a distal view. The deviations from the true CEJ-crest distance demonstrated may be of clinical significance, and a critical attitude to alveolar bone loss measures on radiographs using the RCEJ as reference point is recommended.  相似文献   
56.
SUMMARY This study aimed to assess and compare the impact of letter of invitation, initial breast screening mammography, and subsequent recall procedures on the level of anxiety over breast problems. The survey of females undergoing routine breast screening procedures in a primary care setting is part of the first wave of a national breast screening programme in the UK. Women aged 50-64 registered with six general practices (n=2618) were invited by letter to attend for screening. Their self-perceived impact of receipt of invitation letter, attendance at initial screening, and recall, in terms of anxiety and concern about breast problems, was measured by a self-report questionnaire and the physical, emotional and social dysfunction subscales of the Psychological Consequences of Screening Mammography Questionnaire (PCQ). Overall, subjects' anxiety levels diminished between the receipt of their invitation letter and the completion of their screening examination. Subjects did not, however, respond to the letter of invitation and screening procedure in a homogeneous manner. In a sample of 1253, the letter of invitation reduced anxiety about breast problems in 39.7%, increased anxiety in 24.6%, and had no appreciable effect in 35.7%. In the 1280 who attended for breast screening, the examination procedure reduced anxiety about breast problems in 55.9%, increased anxiety in 12.8%, and had no appreciable effect in 31.3%. In a smaller sample (n=33) who completed questionnaires at recall, there were significant increases in PCQ-measured anxiety. Throughout the study, the PCQ was sensitive to change in anxiety over breast problems. We conclude that screening procedures can either increase or reduce anxiety about breast problems, or have no appreciable effect. Subjects' perception of the impact of receiving the letter of invitation and undergoing the screening examination procedure is related to previous levels of concern over breast problems. Conclusions about the psychological effect of breast screening cannot be drawn without consideration of the time and place of the baseline assessment. Participants in breast screening programmes therefore cannot be considered a homogeneous entity. Caution should be exercised when assessing the impact of screening procedures on entire populations as this approach might mask an important diversity of response.  相似文献   
57.
A review of periodontal disease as a manifestation of HIV infection suggests a shift in emphasis over the past 5 years. Initially the focus was on newly described forms of periodontal disease (ie, HIV-associated gingivitis or linear gingival erythema (LGE); HIV-associated periodontitis or necrotizing ulcerative periodontitis (NUP)). While the clinical definition of LGE varies from study to study, an association between LGE and Candida infection has been described. Furthermore, the prevalence of NUP is quite low and this disorder is associated with severe immunosuppression. In contrast, the focus today is on the accelerated rate of chronic adult periodontitis occurring in seropositive patients. While the organisms that characterize adult periodontitis in seronegative individuals are present in subgingival plaque from seropositive individuals, reports suggest that atypical pathogens are also present (ie, Mycoplasma salivarium, Enterobacter cloacae). Recent studies from our laboratory have identified a novel strain of Clostridium isolated from the subgingival plaque of injecting drug users that has pathologic potential. This organism, however, was found in both seropositive and seronegative individuals in this cohort, suggesting an association with lifestyle rather than serostatus. In addition, data has been published examining the local host response in periodontitis in seropositive individuals. Distinctly elevated levels of IgG in gingival crevicular fluid (GCF) have been observed in seropositive patients. Furthermore, data from our laboratory examining inflammatory mediators in GCF (polymorphonuclear leukocyte lysosomal enzyme β-glucuronidase and the pro-inflammatory cytokine interleukin-1β) suggests an altered response in patients with HIV infection. The alteration manifests as the absence of the expected strong correlation between polymorphonuclear leukocyte activity in the gingival crevice and clinical measures of existing periodontal disease, as well as elevated levels of interleukin-1β in sites with deeper probing depths. Therefore, it can be concluded that the progression of periodontal disease in the presence of HIV infection is dependent upon the immunlogic competency of the host as well as the local inflammatory response to typical and atypical subgingival microorganisms.  相似文献   
58.
Abstract— In the treatment with osseointegrated implants ad modum Brånemark a radiographic control of the fixture-abutment connection is recommended. The purpose of the present study was to analyze the possibilities of detecting incomplete connection by radiography using the recommended technique. In an experimental model the influence of film density, orientation of the fixture hexagon, angulation between film plane and fixture axis, leakage width, and partial connection were analyzed. Slits of 0.05 mm were detectable under optimum projection conditions. On the other hand, slits of 0.1 mm were obscured even at deviations of 5°. A number of factors, e.g. low density level and "unfavorable" orientation of the hexagon in relation to the X-ray beam, reduce the possibilities of detecting slits. It is concluded that in clinical cases a demonstration of incomplete fixture-abutment connection by the use of the recommended radiographic technique radiography to some extent is fortuitous, and that radiographic control has certain limitations.  相似文献   
59.
Enhanced oxidative stress and impairments in nitric oxide synthesis and bioavailability are of considerable importance in the pathogenesis of diabetic vascular diseases. The aim of the present work was to evaluate the metabolic effects of pharmacological doses of the melatonin, a known antioxidant, on streptozotocin-induced diabetic damage in rats. We investigated the indolamine's influence on the cellular redox-balance, nitric oxide (NO) level, and the activities of antioxidative defence enzymes, as well as the activities of enzymes involved in phase II detoxication and NADPH-generating pentose phosphate pathway. Blood glucose, glycated hemoglobin, bilirubin, as well as plasma alanine aminotransferase activities increased and body weight was reduced in rats with streptozotocin-induced (60 mg/kg, i.p.) diabetes (25 days). The NO level was markedly increased in diabetic plasma (by 50%) and aortic tissue (by 30%). The hyperglycemia resulted in reduced activities of glutathione peroxidase (by 25%), catalase (by 20%), glucose-6-phosphate dehydrogenase (by 55%) and transketolase (by 40%) in liver tissue of diabetic animals. Melatonin treatment (10 mg/kg, 18 days) did not influence the level of hyperglycemia or glycated hemoglobin and it had little effect on the activities of antioxidative enzymes. However, melatonin markedly reversed the activities of glucose-6-phosphate dehydrogenase and transketolase in liver tissue of diabetic rats. The most pronounced effect of the melatonin administration was the prevention of an increase in nitric oxide levels in blood plasma and aortic tissue during diabetes. In in vitro experiments, nitrosomelatonin formation in the presence of nitrosodonors was observed. This implies that melatonin might operate as an NO scavenger and carrier. Thus, melatonin treatment may have some beneficial effects in controlling diabetic vascular complications.  相似文献   
60.
问题:广泛性焦虑障碍(GAD)-7量表的诊断精确性如何? 方法 设计:采用盲法比较GAD-7量表与DSM—Ⅳ中的GAD标准。[第一段]  相似文献   
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