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Objective  To examine the effects of various anthropometric determinants on mammographic patterns at postmenopausal ages, accounting for reproductive differences. Methods  Mammograms from 900 post-menopausal women classified into high- (P2/DY) versus low-density (N1/P1) groups using the Wolfe criteria were associated with changes in body figure, reported and measured height and weight, body mass index, hip, waist and chest circumferences, chest/hip ratio, waist/hip ratio (WHR), breast size, and leg length. Reproductive factors included ages at menarche, first pregnancy and menopause, years since menopause, parity, and breast feeding duration. The study was nested within a large cross-sectional survey of a population-based breast cancer screening program in Northern Greece. Results  Increasing chest circumference (p = 0.002), change in body build during adulthood to a heavier profile (p = 0.04), and heavy somatotype at age 18 (p = 0.007) were the anthropometric determinants significantly associated with low-density mammographic patterns. Conclusions  Chest circumference as a measure of upper body fat adiposity appears to be a stronger determinant of mammographic patterns than body fat distribution (measured as WHR). A heavy body build in adulthood is associated with decreased mammographic density. Further studies are necessary to confirm our results, ideally prospective cohorts, looking at the effect of anthropometric determinants on mammographic pattern changes over time and breast cancer risk.  相似文献   
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Several studies have shown that place of death is affected by many parameters. Our objective was to describe for the first time where patients with cancer die in Greece and what has changed between 1993 and 2003. We acquired data on all deaths that were attributed to cancer in Greece in the years 1993 and 2003, and compared these data to the changes in the location of death in the total population. In 1993, approximately 50.7% of men and 50.9% of women cancer patients died in hospital, while in 2003, the respective percentages were 57.3% and 56.1%. The results indicate a trend toward a larger proportion of hospital deaths over this interval. This should be taken under consideration for future planning of end-of-life care in Greece.  相似文献   
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The aim of this study was to evaluate the effects of 3 dentin bonding agents on cell survival and proliferation and on cell cycle progression of cultured cells. The experiments were performed on RPC-C2A and L929 cells. Specimens of the 3 dentin bonding agents (Clearfil Tri-S, AdheSE, and XP BOND) were placed in culture medium, and the extraction media were applied to cells as experimental material. The effect of the bonding materials on cell survival and proliferation was assessed by a modified sulforhodamine B staining assay, and the effect on DNA synthesis was assessed by bromodeoxyuridine uptake. Flow cytometry was used for cell cycle analysis. Cell viability and proliferation decreased in a dose-dependent manner after exposure of cells to the tested materials. XP BOND expressed the highest activity of all tested bonding agents (P < .05). The self-etch bonding agents tested did not produce any significant effects on cell cycle distribution. However, exposure of cells to the total-etch agent XP BOND induced a G2-phase arrest in both cell lines, and this effect was more evident in L929 cells than in RPC-C2A cells.  相似文献   
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CD91 molecule is a multifunctional receptor of alpha 2-macroglobulin, heat-shock proteins and calreticulin. CD91 has been implicated in cross-presentation of peptides chaperoned by these proteins to MHC molecules, thus eliciting antigen-specific immune responses. Hence, CD91 is considered as a major regulator of innate and acquired immune responses. Herein, we show that CD91 molecules are expressed by human salivary gland epithelial cells (SGEC), as indicated by immunohistochemical studies in minor salivary gland biopsy tissues (n = 21) as well as by the analyses of human long-term cultured non-neoplastic SGEC lines (n = 11) and the neoplastic HSG cell line. In these cell lines CD91 expression was evaluated by RT-PCR, flow cytometry and confocal microscopy. Standard internalization assays revealed that HSG and SGECs are capable to bind and internalize the CD91 ligand alpha 2-macroglobulin. This internalization is specific, as attested by inhibition studies using unlabeled alpha 2-macroglobulin and a blocking antibody against human CD91 receptor. Conclusively, our findings indicate that SGEC functionally express CD91 receptor, suggesting that this pathway might be involved in the presentation of exogenous antigens in SGEC.  相似文献   
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Energy homeostasis is regulated by a complex network involving peripheral and central signals that determine food intake and energy expenditure. Melanin-concentrating hormone (MCH) plays an essential role in this process. Animals treated with MCH develop hyperphagia and obesity. Ablation of the prepro-MCH gene leads to a lean phenotype, as does ablation of the rodent MCH receptor, MCHR-1. MCH is overexpressed in the leptin-deficient ob/ob mouse, and we hypothesized that ablation of MCH in this animal would lead to attenuation of its obese phenotype. Compared with ob/ob animals, mice lacking both leptin and MCH (double null) had a dramatic reduction in body fat. Surprisingly, the hyperphagia of the ob/ob mouse was unaffected. Instead, leanness was secondary to a marked increase in energy expenditure resulting from both increased resting energy expenditure and locomotor activity. Furthermore, double-null mice showed improvements in other parameters impaired in ob/ob mice. Compared with ob/ob mice, double-null animals had increased basal body temperature, improved response to cold exposure, lower plasma glucocorticoid levels, improved glucose tolerance, and reduced expression of stearoyl-CoA desaturase 1 (SCD-1). These results highlight the importance of MCH in integration of energy homeostasis downstream of leptin and, in particular, the role of MCH in regulation of energy expenditure.  相似文献   
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BACKGROUND: Several studies assessing the role of obstructive sleep apnea syndrome (OSAS) as an independent risk factor for hypertension have produced conflicting results. Although the sleep apnea syndrome is associated with hypertension, there are no references regarding the blood pressure response of normotensive OSAS patients during exercise. STUDY OBJECTIVES: The aim of this study was to investigate the relationship between diastolic blood pressure (DBP) response during exercise and the severity of OSAS. METHODS: We performed exercise testing a day after polysomnography in 17 normotensive males who were admitted for the first time because of OSAS and in 10 normal subjects who were members of the same families. During maximal incremental exercise test (bicycle ergometry) oxygen consumption (VO(2)) and the DBP were estimated at rest and at peak exercise. VO(2) was also measured when DBP were 100 and 110 mm Hg. RESULTS: At peak exercise DBP was significantly higher in OSAS patients (115.3 +/- 9.2 mm Hg) than in normal subjects (101 +/- 8.4 mm Hg, p < 0.01). OSAS patients reached a DBP of 110 mm Hg with a significantly lower VO(2) than normal subjects (1,881.5 +/- 703.4 vs. 1,972.3 +/- 108.6 ml/min, p = 0.045). VO(2) was not different between the two groups at a DBP of 100 mm Hg (1,211.2 +/- 371.7 vs. 1,536.6 +/- 267.2 ml/min, p = 0.089) but OSAS patients had a significantly lower heart rate than normals (111.2 +/- 13 vs. 118.6 +/- 27.6, p = 0.009). None of the aspects of quality of life, according to the Nottingham Health Profile Questionnaire, Part 1, were significantly different between patients and normal subjects. CONCLUSIONS: Normotensive OSAS patients develop DBP elevation at an earlier stage during exercise compared to normal subjects. This hypertensive response was not correlated with the severity (apnea-hypopnea index, oxygen desaturation parameters) of OSAS. DBP elevation could be a limiting factor of physical performance in this group of patients.  相似文献   
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