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Recently, multiple studies have shown that a sequence variant in CHEK2 (CHEK2 1100delC) plays a role in the susceptibility to breast cancer. This mutation should confer about a twofold increased breast cancer risk in women and a 10-fold increased risk in men. Because the CHEK2 gene plays a critical role in DNA damage repair and the CHEK2 1100delC variant confers susceptibility to breast cancer, we investigated if patients carrying the CHEK2 1100delC mutation are characterized by an enhanced chromosomal radiosensitivity. To this end, familial breast cancer patients, sporadic breast cancer patients, and healthy women, considered in our previously studied to determine their chromosomal radiosensitivity with the G2 and G0-MN assay, were all tested in present study for the presence of the CHEK2 1100delC variant. The 1100delC variant was detected in none of the 100 healthy individuals, in 1 of 100 (1%) unselected breast cancer patients and in 3 of 78 (3.8%) breast cancer patients with a family history of breast cancer. The breast cancer patients with the CHEK2 1100delC genotype had a mean radiation-induced yield of chromatid breaks that was not significantly different from that of the healthy control group. Although the mean yield of micronuclei (MN) was significantly higher compared to the healthy control group, this higher mean MN yield was due to a single patient who had a very high number of MN compared to the parallel control. Our data suggest that breast cancer patients with a CHEK2 1100delC mutation are in general not characterized by a distinct enhanced chromosomal radiosensitivity. These conclusions are, however, very preliminary, because of the small numbers of CHEK2 1100delC breast cancer patients studied.  相似文献   
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OBJECTIVES: To evaluate the effectiveness of a home visiting program on health-related measures in a population of older people with poor health status.
DESIGN: Randomized, clinical trial.
SETTING: Community-dwelling citizens in the Netherlands.
PARTICIPANTS: Three hundred thirty people aged 70 to 84 randomly assigned to an intervention group (n=160) or a control group (n=170).
INTERVENTION: Eight home visits, lasting 1 hour or more, with telephone follow-up, over an 18-month period, conducted by experienced home nurses under supervision of a public health nurse; key elements of the (systematic) visits were assessment of health problems and risks, advice, and referral to professional and community services.
MEASUREMENTS: Self-rated health, functional status, quality of life, and changes in self-reported problems.
RESULTS: No differences were found between the intervention and control group in these and other outcome measures at the end of the intervention period (18 months).
CONCLUSION: The home visiting program did not appear to have any effect on the health status of older people with poor health and are probably not beneficial for such persons.  相似文献   
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Tuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutations in the TSC1 or TSC2 genes. The TSC1 and TSC2 gene products, TSC1 and TSC2, form a complex that inhibits the mammalian target of rapamycin (mTOR) complex 1 (TORC1). Here, we investigate the effects of 78 TSC2 variants identified in individuals suspected of TSC, on the function of the TSC1–TSC2 complex. According to our functional assessment, 40 variants disrupted the TSC1–TSC2‐dependent inhibition of TORC1. We classified 34 of these as pathogenic, three as probably pathogenic and three as possibly pathogenic. In one case, a likely effect on splicing as well as an effect on function was noted. In 15 cases, our functional assessment did not agree with the predictions of the SIFT amino acid substitution analysis software. Our data support the notion that different, nonterminating TSC2 mutations can have distinct effects on TSC1–TSC2 function, and therefore, on TSC pathology.  相似文献   
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Residual mediastinal masses are frequently observed in patients with Hodgkin disease (HD) after completed therapy, and the discrimination between active tumor tissue and fibrotic residues remains a clinical challenge. We studied the diagnostic value of metabolic imaging by 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in detecting active mediastinal disease and predicting relapse. Twenty-eight HD patients with a residual mediastinal mass of at least 2 cm after initial therapy or after salvage chemotherapy were prospectively assigned to 29 examinations with FDG PET and were evaluated as 29 "subjects." Patients were monitored for at least 1 year after examination and observed for signs of relapse. Median follow-up was 28 months (range, 16 to 68 months). A PET-negative mediastinal tumor was observed in 19 subjects, of whom 16 stayed in remission and 3 relapsed. Progression or relapse occurred in 6 of 10 subjects with a positive PET, whereas 4 subjects remained in remission. The negative predictive value (negative PET result and remission) at 1 year was 95%, and the positive predictive value (positive PET result and relapse) was 60%. The disease-free survival for PET-negative and PET-positive patients at 1 year was 95% and 40%, respectively. The difference was statistically significant. A negative FDG PET indicates that an HD patient with a residual mediastinal mass is unlikely to relapse before 1 year, if ever. On the other hand, a positive PET result indicates a significantly higher risk of relapse and demands further diagnostic procedures and a closer follow-up.  相似文献   
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Introduction

Cardiotrophin-1 (CT-1) is a member of the interleukin-6 superfamily with known hypertrophic and protective actions upon cardiac myocytes. Although its effects on myocardial tissue and its role in hypertensive heart disease are well documented, there are no studies on CT-1 blood levels in patients with coronary artery disease. In this study we aimed to verify the relationships of serum CT-1 with vascular disease and metabolic parameters in a population of patients undergoing coronary angiography due to clinical indications.

Material and methods

Serum levels of CT-1 were investigated in a cohort of 81 consecutive patients (median age 68 years (95% CI: 64–71), 59 males) undergoing coronary angiography and carotid Doppler ultrasound. Exclusion criteria were: acute coronary syndrome, already-established ischemic cardiopathy, chronic inflammatory diseases and presence or past history of cancer.

Results

Levels of CT-1 were inversely correlated with body mass index (BMI) and waist circumference (WC) (ρ = –0.261, p = 0.02; ρ = –0.224, p = 0.05, respectively). Moreover, obese patients showed significantly lower CT-1 concentrations than non-obese ones (1.18 (0.64–1.64) ng/ml vs. 1.56 (1.37–2.04) ng/ml, p = 0.013), and serum CT-1 was significantly reduced in patients with elevated compared to those with normal WC (1.43 (0.94–1.60) ng/ml vs. 1.64 (1.39–2.49) ng/ml, p = 0.047). Concentrations of CT-1 did not correlate either with the other parameters of metabolic syndrome or with markers of cardiovascular disease (carotid intima-media thickness, presence of carotid or coronary artery plaques).

Conclusions

Our results failed to demonstrate any association between CT-1 and carotid or coronary disease. The inverse association with BMI and WC fits with the latest experimental data on the role of CT-1 in dysmetabolic conditions and could help to further clarify the role of CT-1 in obesity and diabetes.  相似文献   
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