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101.
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The short-term effects of nitrogen dioxide (NO(2)) on total, cardiovascular and respiratory mortality in 30 European cities participating in the Air Pollution on Health: a European Approach (APHEA)-2 project were investigated. The association was examined using hierarchical models implemented in two stages. In the first stage, data from each city were analysed separately, whereas in the second stage, the city-specific air pollution estimates were regressed on city-specific covariates to obtain overall estimates and to explore sources of possible heterogeneity. A significant association of NO(2) with total, cardiovascular and respiratory mortality was found, with stronger effects on cause-specific mortality. There was evidence of confounding in respiratory mortality with black smoke and sulphur dioxide. The effect of NO(2) on total and cardiovascular mortality was observed mainly in western and southern European cities, and was larger when smoking prevalence was lower and household gas consumption was higher. The effect of NO(2) on respiratory mortality was higher in cities with a larger proportion of elderly persons in the population and higher levels of particulate matter with a 50% cut-off aerodynamic diameter of 10 mum. The results of this large study are consistent with an independent effect of nitrogen dioxide on mortality, but the role of nitrogen dioxide as a surrogate of other unmeasured pollutants cannot be completely ruled out.  相似文献   
104.
New adult patients (n = 212) were randomly assigned to 58 primary care resident physicians. Physician practice styles during initial and return visits were analyzed using the Davis Observation Code. Compared with initial patient visits, return visits were shorter, but more work-intensive. Return visits displayed significantly less technically oriented behavior (including history taking, physical examination, and treatment planning) and fewer discussions regarding use of addictive substances; however, there was more emphasis on health behaviors and active involvement of patients in their own care. These physicians' practice style differences between initial and return patient visits suggest that physician-patient familiarity affects what happens during the medical interview.  相似文献   
105.
The Greek diet is characterized by a high total fat but low saturated fat intake. In a hospital-based case-control study of female breast cancer conducted in Athens (1989-91), 820 patients with confirmed cancer of the breast were compared with 795 orthopaedic patient controls and 753 hospital visitor controls, matched to the cases by age and interviewer. Diet was ascertained through a semiquantitative food frequency questionnaire; macronutrient intakes were estimated from the nutrient content of a selected typical portion size for each specified food item, summed for all items. Logistic regression was used to analyse the data, controlling for demographic and reproductive risk factors for breast cancer as well as for total energy intake and mutual confounding influences among nutrients. There was no significant or suggestive association of total protein, total fat, categories of fat or total carbohydrates with breast cancer risk. Thus, the mutually adjusted relative risk per quintile and (in parenthesis) 95% confidence interval were: for protein, 1.06 (0.94-1.20); saturated fat, 0.99 (0.89-1.11); monounsaturated fat, 0.97 (0.88-1.07), polyunsaturated fat, 1.05 (0.97-1.13); and total carbohydrates, 1.03 (0.94-1.12). In alternative analytical approaches only total protein appeared to be positively associated to the occurrence of breast cancer with some consistency, but the results were far from statistically significant. These findings do not support a role for fat or other energy-generating nutrients in the aetiology of breast cancer.  相似文献   
106.
Data from 1,575 cases and 1,974 controls enrolled in 6 previously conducted case-control studies of diet and breast cancer have been analysed with respect to alcohol intake. There appears to be an absence of any association between consumption of up to 40 g of alcohol per day and risk of breast cancer, and a highly statistically significant and consistent elevated risk of breast cancer for drinkers of 40 g or more of alcohol per day, for whom the relative risk, as compared with that of non-drinkers, is 1.69 (95% confidence interval 1.19 to 2.40). This association is not due to confounding by a number of diet-related factors, including total calories, fat, fibre and vitamin C.  相似文献   
107.
Data concerning histories of Adenoidectomy (Ad), Tonsillectomy (T) and Appendectomy (Ap) were collected from the escorts (mainly mothers) of 2296 children 3-12 years-old. The children were admitted as outpatients at the First Department of Paediatrics of the University of Athens or the Polyclinic of the Children's Welfare Center of PIKPA in Pireaus, during the last six months of 1983. Among children with median age of about six years, 12 percent had already had at least one operation (Ad, T or Ap); this proportion increased to about 25 percent among children with median age of about 10 years. The cumulative incidence of Ad and/or T was higher among boys, whereas the cumulative incidence of Ap was higher among girls. The age adjusted cumulative incidence of Ap was significantly higher in the lower social class, whereas there was no social gradient with respect to Ad or T. There were strong intra-individual correlations among the three studied operations; in particular the age adjusted cumulative incidence of Ap was 2.9 times higher among children with Ad and/or T than among children without any of these operations. Since there are no apparent biomedical reasons to account for the observed intra-individual associations, it appears likely, that these associations reflect parental or physician's attitudes leading to unjustifiable operations in some of the children.  相似文献   
108.
Diet and breast cancer: a case-control study in Greece   总被引:5,自引:0,他引:5  
A case-control study of the role of diet in the etiology of breast cancer was conducted in Athens, Greece. There are reasons to believe that the diet of the Greek population is characterized by greater heterogeneity than that in most countries where such studies have been undertaken. The case series consisted of 120 consecutive patients with histologically confirmed breast cancer admitted to either of two teaching hospitals over a 12-month period. The controls were 120 patients admitted to a teaching hospital for trauma and orthopedic conditions during the same period. Dietary histories concerning the frequency of consumption of 120 foods and drinks were obtained by interview. Cases reported significantly less frequent consumption of vegetables as a group and, within that group, specifically of cucumber, lettuce and raw carrot. After adjustment for potential external confounding variables and for confounding between food categories, the odds ratio for persons in the highest quintile of vegetable consumers, relative to those in the lowest quintile, was 0.09 with 95% confidence limits 0.03-0.30. That is to say, the lowest quintile of vegetable consumers had about 10 times the breast cancer risk of the highest quintile. For a score based on consumption of only the 3 specified salad items the odds ratio over the extreme quartiles was 0.12 (0.05-0.32). There was no association with consumption of fats and oils, alcohol or coffee, and no significant association with any other major food category (including alcohol and coffee) after adjustment for confounding variables.  相似文献   
109.

Background

Signaling through the B-cell receptor appears to be a major contributor to the pathogenesis of chronic lymphocytic leukemia. Toll-like receptors bridge the innate and adaptive immune responses by acting as co-stimulatory signals for B cells. The available data on the expression of Toll-like receptors in chronic lymphocytic leukemia are limited and derive from small series of patients.

Design and Methods

We profiled the expression of genes associated with Toll-like receptor signaling pathways in 192 cases of chronic lymphocytic leukemia and explored potential associations with molecular features of the clonotypic B-cell receptors.

Results

Chronic lymphocytic leukemia cells express all Toll-like receptors expressed by normal activated B cells, with high expression of TLR7 and CD180, intermediate expression of TLR1, TLR6, TLR10 and low expression of TLR2 and TLR9. The vast majority of adaptors, effectors and members of the NFKB, JNK/p38, NF/IL6 and IRF pathways are intermediately-to-highly expressed, while inhibitors of Toll-like receptor activity are generally low-to-undetectable, indicating that the Toll-like receptor-signaling framework is competent in chronic lymphocytic leukemia. Significant differences were identified for selected genes between cases carrying mutated or unmutated IGHV genes or assigned to different subsets with stereotyped B-cell receptors. The differentially expressed molecules include receptors, NFκB/MAPK signaling molecules and final targets of the cascade.

Conclusions

The observed variations are suggestive of distinctive activation patterns of the Toll-like receptor signaling pathway in subgroups of cases of chronic lymphocytic leukemia defined by the molecular features of B-cell receptors. Additionally, they indicate that different or concomitant signals acting through receptors other than the B-cell receptor can affect the behavior of the malignant clone.  相似文献   
110.
A solid phase immunoassay was used to evaluate the levels of serum and cerebrospinal fluid of alphafetoprotein and carcinoembryonic antigen in 33 individuals treated for backache and headache with no evidence of organic neurological disease, 19 patients with primary CNS tumor (benign or malignant) and 22 with CNS metastasis from a solid tumor. AFP serum and CSF levels were found in trace amounts or slightly elevated not exceeding normal limits in all groups. Patients with CNS metastasis were found to have statistically significant higher CEA levels (both in serum and CSF) than the control group, and the patients with primary brain tumors. Patients with leptomeningeal dissemination had statistically significantly higher CEA CSF levels than did patients with primary tumors, and patients with parenchymal metastasis.  相似文献   
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