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BACKGROUND: Menthol is a natural herbal compound. Its isomer l-menthol presents the characteristic peppermint scent and is also responsible for the cooling sensation when applied to nasal mucosal surfaces because of stimulation of trigeminal cold receptors. The aim of this study was to assess the effect of menthol inhalation on end-inspiratory nasal mucosa temperature and nasal patency. METHODS: Eighteen healthy volunteers with a mean age of 30 years were enrolled in this study. Objective measurements included the septal mucosal temperature within the nasal valve area by using a miniaturized thermocouple as well as active anterior rhinomanometry before and after inhalation of l-menthol vapor. All subjects completed a visual analog scale (VAS; range, 1-10) evaluating nasal patency before and after menthol. RESULTS: The mean end-inspiratory mucosal temperature ranged from 27.7 degrees C (+/-4.0) before menthol inhalation to 28.5 degrees C (+/-3.5) after menthol inhalation. There were no statistically significant differences between the temperature values before and after menthol inhalation (p > 0.05). In addition, no statistically significant differences between the rhinomanometric values before and after menthol inhalation were observed. Sixteen of the 18 subjects reported an improvement of nasal breathing after menthol inhalation by means of the VAS. CONCLUSION: Menthol inhalation does not have an effect on nasal mucosal temperature and nasal airflow. The subjective impression of an improved nasal airflow supports the fact that menthol leads to a direct stimulation of cold receptors modulating the cool sensation, entailing the subjective feeling of a clear and wide nose.  相似文献   
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Aims—To investigate the immunohistochemical expression of bcl-2 and p53 proteins in nasopharyngeal carcinomas in relation to the expression of the Epstein-Barr virus (EBV) encoded EBER messenger RNAs (mRNAs) and latent membrane protein-1 (LMP-1).  相似文献   
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AIMS: This study investigated whether chronic and acute amiodarone treatment has differential effects on ventricular arrhythmogenesis during acute myocardial infarction in rats. METHODS AND RESULTS: Forty-six rats were randomly allocated into vehicle, chronic oral amiodarone (30 mg/kg daily for 2 weeks), or acute amiodarone (a single dose, 100 mg/kg). Five additional rats were sham-operated. Myocardial infarction was generated by left coronary artery ligation 2 weeks after chronic treatment. Amiodarone was administered acutely 5 min post-ligation. The electrocardiogram was recorded for 24 h, using an implanted telemetry transmitter. Episodes of ventricular tachyarrhythmias and mortality rates were analysed. Serum catecholamines and infarct size were measured 24 h post-ligation. No differences were found in infarct size. Compared with controls (22.7 +/- 10.9), there was a similar reduction in the number of tachyarrhythmia episodes after either chronic (2.6 +/- 1.6, P = 0.0011) or acute (3.6 +/- 1.7, P = 0.031) amiodarone administration. Norepinephrine levels were lower only after chronic treatment. Mortality in both amiodarone treatment arms was exclusively due to bradyarrhythmia secondary to cardiac failure, whereas mortality in controls was mainly attributed to tachyarrhythmic death. CONCLUSIONS: A rapid antiarrhythmic effect was observed after acute amiodarone administration in the rat. Norepinephrine levels decreased after chronic treatment and may be associated with bradyarrhythmic mortality.  相似文献   
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It is a common knowledge that metabolic reactions increase in hyperthyroidism and decrease in hypothyroidism. The aim of this work was to investigate how the metabolic reactions could affect the total antioxidant status (TAS), protein concentration (PC) and the activities of acetylcholinesterase (AChE), (Na+,K+)-ATPase and Mg2+-ATPase in the brain of hyper- and hypothyroid adult male rats. Hyperthyroidism was induced in rats by subcutaneous administration of thyroxine (25 g/100 g body weight) once daily for 14 days, while hypothyroidism was induced by oral administration of propylthiouracil (0.05%) for 21 days. TAS, PC, and enzyme activities were evaluated spectrophotometrically in the homogenated brain of each animal. TAS, PC, and Mg2+-ATPase activity were found unaffected in hyperthyroidism, while AChE and Na+,K+-ATPase activities were reduced by 25% (p < 0.01). In contrast, TAS, (Na+,K+)-ATPase and Mg2+-ATPase activities were found to be increased (approx. 23–30%, p < 0.001) in the hypothyroid brain, while AChE activity and PC were shown to be inhibited (approx. 23–30%, p < 0.001). These changes on brain enzyme activities may reflect the different metabolic effects of hyper- and hypothyroidism. Such changes of the enzyme activities may differentially modulate the brain intracellular Mg2+, neural excitability, as well as the uptake and release of biogenic amines.  相似文献   
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Purpose

Stomach adenocarcinoma represents a major health problem and is regarded as the second commonest cause of cancer-associated mortality, universally, since it is still difficult to be perceived at a curable stage. Several lines of evidence have pointed out that the expression of l-Dopa decarboxylase (DDC) gene and/or protein becomes distinctively modulated in several human neuroendocrine neoplasms as well as adenocarcinomas.

Methods

In order to elucidate the clinical role of DDC on primary gastric adenocarcinomas, we determined qualitatively and quantitatively the mRNA levels of the gene with regular PCR and real-time PCR by using the comparative threshold cycle method, correspondingly, and detected the expression of DDC protein by immunoblotting in cancerous and normal stomach tissue specimens.

Results

A statistically significant association was disclosed between DDC expression and gastric intestinal histotype as well as tumor localization at the distal third part of the stomach (p = 0.025 and p = 0.029, respectively). Univariate and multivariate analyses highlighted the powerful prognostic importance of DDC in relation to disease-free survival and overall survival of gastric cancer patients. According to Kaplan–Meier curves, the relative risk of relapse was found to be decreased in DDC-positive (p = 0.031) patients who, also, exhibited higher overall survival rates (p = 0.016) than those with DDC-negative tumors.

Conclusions

This work is the first to shed light on the potential clinical usefulness of DDC, as an efficient tumor biomarker in gastric cancer. The provided evidence underlines the propitious predictive value of DDC expression in the survival of stomach adenocarcinoma patients.  相似文献   
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Objectives Sildenafil may be beneficial during myocardial ischaemia/reperfusion, but this effect may be dose‐dependent, accounting for previous conflicting results. We have explored the effects of two acute and one chronic administration regimen on left ventricular function. Methods The study was conducted on 36 Wistar rats (290 ± 7 g). Sildenafil was administered 30 min before ischaemia at a low (0.7 mg/kg, n= 8) or high (1.4 mg/kg, n= 8)dosage. The chronic treatment arm (n= 8) consisted of two daily injections of sildenafil (0.7 mg/kg) for three weeks. The control group was formed by 12 rats. Ischaemic contracture, post‐ischaemic recovery and hypercontracture were measured in isolated, Langendorff‐perfused preparations. Key findings Ischaemic contracture tended to be lower after high‐dose sildenafil, while remaining unchanged after low‐dose or chronic sildenafil administration. Compared with controls (62.9 ± 2.0% of baseline developed pressure), post‐ischaemic recovery was higher (P= 0.0069) after low dose (75.1 ± 2.4%), unchanged (P= 0.13) after high dose (69.1 ± 2.1%), but lower (P < 0.001) after chronic (42.9 ± 4.5%) sildenafil administration. Compared with controls (71.8 ± 3.9 mmHg), hypercontracture was higher (P= 0.0052) after chronic sildenafil administration (89.5 ± 4.1 mmHg), but similar after acute low dose (65.7 ± 3.3 mmHg, P= 0.33) or high dose (67.1 ± 4.7 mmHg, P= 0.43). Conclusions The effects of sildenafil after ischaemia/reperfusion were strongly dose‐dependent. Beneficial actions on left ventricular function were evident after acute pretreatment with a low dosage, but were lost after doubling the dose. Chronic sildenafil administration deteriorated left ventricular function during ischaemia and reperfusion.  相似文献   
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In recent years, molecular imaging with [(18)F]fluorodeoxyglucose-positron-emission tomography, [(18)F]FDG-PET, has become part of the standard of care in initial staging of patients with non-small-cell lung cancer. Currently, there is an increasing interest in the role of [(18)F]FDG-PET in the evaluation of biological characteristics of the tumor and the prediction of response to anticancer therapies at an early phase of treatment. According to the existing data, quantitative assessment of therapy-induced changes in tumor [(18)F]FDG uptake may allow the prediction of tumor response and patient outcome very early in the course of therapy. Treatment may be adjusted according to the chemosensitivity of the tumor tissue in an individual patient. Thus, [(18)F]FDG-PET has the potential to reduce the side effects and costs of ineffective therapy. This review provides an update on recent studies that evaluate the role of [(18)F]FDG-PET in the early prediction of response to chemotherapy and prognosis in patients with non-small-cell lung cancer. In addition, it discusses the application of [(18)F]FDG-PET to the monitoring of new targeted forms of anticancer therapy and particularly of epidermal growth factor receptor tyrosine kinase inhibitors. Finally, it evaluates the usefulness of [(18)F]fluorothymidine, a PET tracer for imaging tumor proliferation, in predicting response to therapy in patients with lung cancer.  相似文献   
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