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41.
BACKGROUND: Haemodialysis catheters used for vascular access are frequently complicated by infection and catheter-related thrombosis. Improvement of interdialytic locking solutions could reduce these problems. Trisodium citrate (TSC) has been advocated in recent years because it might have antimicrobial qualities. METHODS: Antimicrobial efficacy of four concentrations of TSC (2.2, 7.5, 15 and 30%) was compared with three equi-osmolal sodium chloride (NaCl) concentrations, unfractionated heparin 5000 IU/ml and a solution of gentamicin 1 mg/ml in TSC 7.5%. We analysed antimicrobial properties by two classical in vitro susceptibility tests. All tests were performed in triplicate by incubation of test fluids with Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa and Candida albicans. RESULTS: Increasing TSC concentrations effectively killed the staphylococcal strains in both assays. For E.coli and P.aeruginosa complete killing was achieved only with TSC 30%. TSC 30% was also the only solution that significantly inhibited growth of C.albicans. Heparin manifested no antimicrobial effect of any significance. Adding gentamicin to TSC provided superior bacterial growth inhibition but had no effect on yeast growth. TSC solutions manifested superior antimicrobial activity compared with iso-osmolal NaCl solutions in both assays. CONCLUSION: This in vitro study demonstrates superior antimicrobial activity of TSC, especially in higher concentrations, in contrast to heparin. The mechanism seems to differ from hyperosmolality. Ca(2+) and Mg(2+) chelating effects are probably more important. Adding gentamicin provided the most potent antimicrobial solution. However, for reasons concerning development of bacterial resistance and sensitization of the patient, continuous exposition to aminoglycosides seems not advisable.  相似文献   
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Background Many breast, cervical, and colorectal cancer screening programmes were disrupted due to the COVID-19 pandemic. This study aimed to estimate the effects of five restart strategies after the disruption on required screening capacity and cancer burden.Methods Microsimulation models simulated five restart strategies for breast, cervical, and colorectal cancer screening. The models estimated required screening capacity, cancer incidence, and cancer-specific mortality after a disruption of 6 months. The restart strategies varied in whether screens were caught up or not and, if so, immediately or delayed, and whether the upper age limit was increased.Results The disruption in screening programmes without catch-up of missed screens led to an increase of 2.0, 0.3, and 2.5 cancer deaths per 100 000 individuals in 10 years in breast, cervical, and colorectal cancer, respectively. Immediately catching-up missed screens minimised the impact of the disruption but required a surge in screening capacity. Delaying screening, but still offering all screening rounds gave the best balance between required capacity, incidence, and mortality.Conclusions Strategies with the smallest loss in health effects were also the most burdensome for the screening organisations. Which strategy is preferred depends on the organisation and available capacity in a country.Subject terms: Health policy, Population screening, Cancer screening, Cancer screening  相似文献   
44.
AIMS: To describe five malignant tumours in the breast (two invasive carcinomas and three non-Hodgkin's lymphomas) showing an unusual pattern of spread within anastomosing spaces consistent with those described in pseudoangiomatous stromal hyperplasia. METHODS AND RESULTS: The histological and immunohistochemical features of the cases are presented. In all cases, the neoplasms consisted of non-cohesive E-cadherin-negative cells located within anastomosing vascular-like channels. These channels showed morphological and immunohistochemical features consistent with those seen in pseudoangiomatous stromal hyperplasia: they were lined by flattened cells that expressed CD34, bcl2 and smooth muscle actin, while CD31 was consistently negative. CONCLUSIONS: The open channels of pseudoangiomatous stromal hyperplasia have been regarded as spaces due to loss of cohesiveness between stromal fibroblasts if not artefacts. The fact that neoplastic cells spread through these spaces suggests that the spaces are true open channels that may represent part of a complex network of stromal channels (pre-lymphatics) connected to the main lymphatic system of the breast. This finding opens new insights into the routes of tumour spread.  相似文献   
45.
Cyclin D1 overexpression, detected by standard immunohistochemistry, was correlated with other prognostic variables and its prognostic value was evaluated in a group of 148 invasive breast cancers with long-term follow-up. Overexpression of cyclin D1 (59% of cases) was negatively correlated (chi 2 test) with histological grade (P = 0.0001), mean nuclear area (P = 0.004), mean nuclear volume (P = 0.02), and mitotic activity (P = 0.03) and positively correlated with estrogen receptor (P = 0.0001). There was a strong correlation between cyclin D1 overexpression and histological type (P = 0.0001). Positive cyclin D1 staining was seen in 11 of 13 tubular carcinomas, 3 of 3 mucinous carcinomas, 4 of 4 invasive cribriform carcinomas, and 17 of 20 lobular carcinomas. Of 102 ductal cancers, 52 were positive, and all 6 medullary carcinomas were negative. There were no significant correlations with lymph node status, tumor size, or DNA ploidy. In survival analysis, cyclin D1 overexpression did not provide significant univariate or multivariate prognostic value. In conclusion, cyclin D1 is mainly overexpressed in the well differentiated and lobular types of invasive breast cancer and is strongly associated with estrogen receptor positivity. It is negatively correlated with the proliferation marker mitoses count and with the differentiation markers nuclear area and nuclear volume. However, cyclin D1 overexpression does not seem to have prognostic value in invasive breast cancer when no adjuvant treatment is given.  相似文献   
46.
Summary To determine the effect of age and comorbid diseases on treatment choice and survival, the medical records of 300 breast cancer patients of 55 years and older were reviewed. All patients were admitted to the Netherlands Cancer Institute (NKI) for first treatment between 1980 and 1987. Patients were classified according to severity level of comorbid diseases. Physicians were found to treat women of 75 years and older less often with adjuvant radiotherapy after a mastectomy, and more often to employ only primary endocrine treatment for local stage disease, as compared with younger patients. According to the treatment guidelines of the institute, the study sample was divided into patients who received standard vs. non-standard treatment. The treatment of 38 women (13.1%) did not correspond with the guidelines. Of these, 84% were 75 years and older and 50% had a severe comorbidity status. Logistic regression analysis indicated that advanced age, per se, was a better indicator of the risk of not being treated according to protocol than the comorbidity status. Cox multivariate analyses demonstrated that neither the severity of the comorbidity status nor the differences in treatment between younger and older patients had a significant effect on the risk of dying from breast cancer or on the risk of developing recurrences. In this analysis, age 75 years or more proved to be a significant and independent predictor of a worse overall and disease-specific survival as compared to age between 65–74 years.  相似文献   
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48.
Hoebers FJ  Borger JH  Hart AA  Peterse JL  Th EJ  Lebesque JV 《Cancer》2000,88(7):1633-1642
BACKGROUND: The objective of the current study was to evaluate the effectiveness and morbidity of primary axillary radiotherapy in breast-conserving therapy for postmenopausal, clinically axillary lymph node negative patients with early stage breast carcinoma. METHODS: Between 1983-1997, 105 patients with clinically negative axillary lymph nodes and breast carcinoma were treated with wide local excision followed by radiotherapy to the breast, and axillary and supraclavicular lymph node areas. Adjuvant treatment with tamoxifen was given to 75 patients. The median follow-up of patients still alive was 41 months (range, 8-137 months). Fifty-five patients with no evidence of disease at last follow-up were examined prospectively with respect to late functional damage. RESULTS: The mean age of the patients was 64 years. Three patients developed a local recurrence. No isolated axillary lymph node recurrence was observed. In two patients, axillary recurrence was accompanied by distant metastases. The 5-year disease free interval and the overall survival were 82% (standard error [SE], 6%) and 83% (SE, 6%), respectively. In five patients, arm edema was reported and impaired shoulder function was reported in seven patients. Prospectively scored, arm edema was reported subjectively by the patient in 4% and objectively measured in 11% of cases. Impaired shoulder function was reported subjectively in 35% and objectively measured in 17% of cases. No brachial plexus neuropathy was noted. CONCLUSIONS: Primary axillary radiotherapy for postmenopausal women with clinically lymph node negative, early stage breast carcinoma was found to result in low axillary lymph node recurrence rates with only limited late complications. Therefore, primary axillary radiotherapy should be considered as axillary treatment in selected patients as an alternative to axillary lymph node dissection.  相似文献   
49.

Introduction

To tailor local treatment in breast cancer patients there is a need for predicting ipsilateral recurrences after breast-conserving therapy. After adequate treatment (excision with free margins and radiotherapy), young age and incompletely excised extensive intraductal component are predictors for local recurrence, but many local recurrences can still not be predicted. Here we have used gene expression profiling by microarray analysis to identify gene expression profiles that can help to predict local recurrence in individual patients.

Methods

By using previously established gene expression profiles with proven value in predicting metastasis-free and overall survival (wound-response signature, 70-gene prognosis profile and hypoxia-induced profile) and training towards an optimal prediction of local recurrences in a training series, we establish a classifier for local recurrence after breast-conserving therapy.

Results

Validation of the different gene lists shows that the wound-response signature is able to separate patients with a high (29%) or low (5%) risk of a local recurrence at 10 years (sensitivity 87.5%, specificity 75%). In multivariable analysis the classifier is an independent predictor for local recurrence.

Conclusion

Our findings indicate that gene expression profiling can identify subgroups of patients at increased risk of developing a local recurrence after breast-conserving therapy.  相似文献   
50.
In this review, we comment on the reasons for disagreement in the concepts, diagnosis and classifications of pre-invasive intraductal proliferations. In view of these disagreements, our proposal is to distinguish epithelial hyperplasia, lobular carcinoma in situ and ductal carcinoma in situ, and to abandon the use of poorly reproducible categories, such as atypical ductal hyperplasia or ductal intraepithelial neoplasia, followed by a number to indicate the degree of proliferation and atypia, as these are not practical for clinical decision making, nor for studies aimed at improving the understanding of breast cancer development. If there is doubt about the classification of an intraductal proliferation, a differential diagnosis and the reason for and degree of uncertainty should be given, rather than categorizing a proliferation as atypical.  相似文献   
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