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1.
Abstract

The purpose of this study was to investigate the strength of the relationships between self-efficacy and (i) functional exercise capacity and (ii) physical activity in chronic obstructive pulmonary disease (COPD), and whether self-efficacy assessment type (i.e., COPD symptoms, exercise-task, exercise-barrier, general, falls) and physical activity assessment type (i.e., self-report vs. objective) are moderators. A systematic search of COPD and self-efficacy concepts was conducted using eight databases from inception to 23 January 2019. Studies were included if they provided correlation coefficients of the relationship between self-efficacy and functional exercise capacity or physical activity, were conducted in adults diagnosed with COPD, and were published in English-language journals. A total of 14 correlation coefficients were included in the self-efficacy and functional exercise capacity meta-analysis, and 16 in the self-efficacy and physical activity meta-analysis. Data were screened, reviewed, and extracted independently by two reviewers, with discrepancies resolved by a third reviewer. Stronger self-efficacy was associated with better functional exercise capacity (weighted r?=?0.38, 95%CI [0.25, 0.50]), and greater physical activity (weighted r?=?0.25, 95%CI [0.17, 0.34]). Exercise-task self-efficacy had the strongest relationship to functional exercise capacity (weighted r?=?0.64, 95% CI [0.51, 0.73]). For physical activity, the type of self-efficacy most strongly related was inconclusive. In COPD, self-efficacy has a relationship to functional exercise capacity and physical activity, the strength of which is influenced by the choice of self-efficacy measure. An understanding of these relationships will assist clinicians in selecting the self-efficacy measure most closely related to the outcome of interest.  相似文献   
2.
This research presents the first extensive mutational study of N-terminal amino acids necessary for activity of a bacterial Zeta class glutathione transferase (GST). Our studies on UG30 tetrachlorohydroquinone reductive dehalogenase (PcpC) revealed that, similar to other Zeta class GSTs, N-terminal Ser and Cys residues play critical roles in glutathione binding and their mutation results in functional and structural changes to PcpC. Mutation of the N-terminal Ser and Cys residues decreased the apparent temperature optimum (by 6-10 °C) and maximum (by 5 °C) of PcpC. Also, mutation of Ser12 and Ser15 resulted in structural changes that were accompanied by the emergence of substrate inhibition. Mutation of the N-terminal Cys residue adversely affected the rate of the enzymatic reaction, but not on the metabolites formed. This study adds to the knowledge that, despite low sequence homology for the Zeta GST protein family, differences in preferred electrophilic substrates, and the manner in which glutathione is utilized in catalysis, GSTs from prokaryotic and eukaryotic organisms rely upon the same critical amino acids for glutathione binding.  相似文献   
3.
Theophylline alone or in the presence of 0.001, 0.01, 0.1 or 1 microgram oestradiol-17 beta/100 g body wt increase uterine RNA and protein content 6 h after administration. Uterine oedema induced by physiological doses of oestradiol-17 beta was increased further in the presence of theophylline. Theophylline decreased the number of eosinophils in the blood and concurrently decreased oestrogen-induced uterine oesinophilia at doses of 0.01, 0.1, 1, 10 or 30 micrograms oestradiol-17 beta/100 g body wt. Oestrogen binding by uterine eosinophils in vitro increased in the presence of theophylline. This effect of theophylline could explain the increase of oestrogen-induced uterine oedema in vivo.  相似文献   
4.
5.
Thermal therapy, Part III: ablation techniques   总被引:2,自引:0,他引:2  
Ablative treatments are gaining increasing attention as an alternative to standard surgical therapies, especially for patients with contraindication or those who refuse open surgery. Thermal ablation is used in clinical applications mainly for treating heart arrhythmias, benign prostate hyperplasia, and nonoperable liver tumors; there is also increasing application to other organ sites, including the kidney, lung, and brain. Potential benefits of thermal ablation include reduced morbidity and mortality in comparison with standard surgical resection and the ability to treat nonsurgical patients. The purpose of this review is to outline and discuss the engineering principles and biological responses by which thermal ablation techniques can provide elevation of temperature in organs within the human body. Because of the individual problems associated with each type of treatment, a wide range of ablation techniques have evolved including cryoablation as well as ultrasound, radiofrequency (RF), microwave, and laser ablation. Aspects of each ablation technique, including mechanisms of action, equipment required, selection of eligible patients, treatment techniques, and patient outcomes are presented, along with a discussion of limitations of the techniques and future research directions.  相似文献   
6.
7.
Postpneumonectomy syndrome is defined as an airway obstruction due to mediastinal shift and rotation after pneumonectomy. A patient who had undergone a left pneumonectomy for bronchial carcinoma 13 years before presented with tension pneumothorax of her remaining lung. Although all factors relevant to the development of postpneumonectomy syndrome were ascertained, the patient had a pneumothorax rather than an airway obstruction. This pneumothorax was treated surgically. The goal of this operation was to reduce the right pleural cavity volume by implanting an intrapleural prosthesis in the pneumonectomy cavity. This treatment is identical to that used for postpneumonectomy syndrome, which allows the right lung to be rejoined with the thoracic wall.  相似文献   
8.
Long-Evans rats, 4-6 weeks of age, were given access to 0, 1, 10, or 100 ppm sodium chlorite in deionized water ad libitum as drinking water. Males were exposed 56 days, and females for 14 days prior to breeding and throughout the 10-day breeding period. Males were evaluated for sperm parameters and reproductive tract histopathology following the breeding period. Females were exposed throughout gestation and lactation. Dams and pups were necropsied at weaning. Decreases in serum T3 and T4 were observed on Postnatal Days 21 and 40 in male and female pups exposed to 100 ppm chlorite or above. Additionally, groups of males were exposed to 0, 10, 100, or 500 ppm ad libitum in the drinking water to confirm observed subtle reproductive effects and examine dose-effect relationships. A significant increase in the percentage of abnormal sperm morphology (P less than 0.001) and decrease in sperm direct progressive movement (P less than 0.01) were observed for adult males at chlorite levels of 100 or 500 ppm. Since other clinical and reproductive endpoints were not affected, sperm morphology and sperm direct progressive movement may be two of the more sensitive indicators of reproductive damage.  相似文献   
9.

Objective

To measure the awareness regarding the concepts of brain death and organ donation among secondary school students within the age range of 12–18 years in the southern region of Saudi Arabia.

Method

In the southern region of Saudi Arabia, 10 secondary schools were randomly chosen to participate in this study for which all the tree levels of secondary schools were visited and a written questionnaire was distributed to a randomly selected student from all 3 levels. The questionnaire was filled and completed anonymously and then analyzed.

Results

Among the 649 students surveyed, 47.22% were aware of brain death and 53.78% did not know anything about organ donation. Further, among those who had heard about these terms, 60% had received the information from informal sources like their friends or through casual web surfing; only a few had received the information from formal sources like television and the radio. The students' understanding of concepts regarding the nature of death and the causes of brain death was, as expected, inadequate and inappropriate. The Islamic perspective on brain death and the knowledge about the Sharia ruling on organ donation was also poor. Regarding the students' knowledge about organ donation, 21.57% of the students knew that organs can be donated from a brain-dead person. 24.6% knew that only living persons can donate organs, while the rest (53.78%) were not aware about organ donation at all.

Conclusion

The knowledge of and attitude toward brain death and organ donation are very poor among the young Saudi population, and have not evolved over a period of time. The information regarding the religious fatwas has not been transmitted to the level of the educational institutions.  相似文献   
10.
Although the use of stents has limited the incidence of restenosis, in-stent restenosis remains an important problem. In-stent restenosis is the result of a healing process that induced neointimal hyperplasia through mechanisms that are still not understood. The aim of this study was to analyze the histological consequences of the healing process following stent implantation. Internal mammary arteries from atheroslerotic patients undergoing coronary artery bypass surgery were stented and maintained in culture for 0-28 days. Stent implantation after predilatation induced an extensive loss of endothelial cells whereas direct stenting preserved endothelium between the struts. Morphometric analysis shows that stent placement induced neointimal thickening. Smooth muscle alpha-actin labeling indicates that neo-intimal formation was mainly due to proliferation and migration of smooth muscle cells. Smooth muscle cell proliferation, assessed by MIB-1 staining, was maximal at day 14 after stent insertion. Human mammary artery organ culture thus provides valuable information on histological consequences of stent implantation with or without predilatation regarding endothelial cell disappearance and neointimal hyperplasia. These data also demonstrate that neointimal thickening induced by stent implantation comprises an intrinsic component resulting from the vessel wall response to stent insertion and suggest that blood factors could play an amplifying but not necessary role.  相似文献   
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