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51.
52.
A Gamsa  R E Braha  R F Catchlove 《Pain》1985,22(1):91-96
Although group therapy is used in a number of multidisciplinary pain treatment centres, few published accounts of procedures are available. The present report describes the use of a moderately directive group therapy method, integrating psychodynamic, cognitive, and behavioural models of therapy. Content of sessions was structured to address problems specific to chronic pain patients. The therapist provided interpretations and confronted patients when appropriate. Problems encountered are described, and two examples are presented. Ideas for improved approaches to group therapy are discussed, with special emphasis on a method integrating physical and psychological therapy.  相似文献   
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Objective Skin tumors and their preliminary stages may be recognized and compensated as an occupational disease only after exposure to soot, raw paraffin, tar, anthracene, pitch or similar substances. The presented study was carried out in one of the world’s largest tar refineries and special attention was paid to the dermatological long-term effects and today’s relevance of tar-induced skin lesions. Methods The data were generated by means of a standardized questionnaire based on occupational disease records and dermatological reports that have been carried out on a regular basis retrospectively. Among other things, the localization, the number and type of skin tumor, the date of diagnosis and the histological evaluation, where available, were taken into account. Results In a longitudinal analysis from 1946 to 2002, a total of n = 618 employees were examined. Squamous cell carcinomas n = 393, basal cell carcinomas n = 298, keratoacanthomas n = 194 and melanomas n = 6 were diagnosed. Latency periods for keratoacanthomas (median 29.5 years) and squamous cell carcinomas (median 28.0 years) were almost identical and could possibly imply that the pathomechanisms for both types of skin tumor might be comparable. Of the persons diagnosed, the skin tumors were mainly localized in the head region (n = 1,662). A remarkable divergence in the localization and distribution of the lesions was found when compared to the general population, for example the relative susceptibility of the upper lip (n = 67) compared to the lower lip (n = 31) as well as the less sun-exposed forearms (n = 381) compared to the back of the hand (n = 331), being typically preferred sites of squamous cell carcinomas. Furthermore, a discrepancy between the distribution of premalignant nonmelanoma skin tumors and carcinomas on the back of the nose, which is more exposed to the sun (n = 56) and those in the nostrils (n = 89), which are less exposed to the sun, but are in the act of breathing more exposed to tar, could be found. Conclusions Tar-induced skin lesions are still of importance nowadays, which is reflected in the incidence of new cases and in the relapses of skin tumors. As a consequence, intensified measures are necessary, in the form of primary and secondary prevention. In view of the high incidence of malignant skin tumors in the general public, it is urgently necessary to take occupational hazards into consideration as well. The present publication is based on the MD thesis of Renata Scheriau.  相似文献   
55.
In 46 hypertensive patients with unilateral renal arterial stenosis, peripheral and renal venous plasma renin activity, juxtaglomerular cell count and granularity and systolic pressure gradient across the stenosis were determined. After corrective surgery and a mean postoperative observation period of 4.3 years, 18 patients were completely relieved of hypertension (good responders), 14 had a substantial reduction in arterial pressure (fair responders) and 14 remained hypertensive (poor responders). Analysis of plasma renin activity in both renal veins indicated that a ratio (stenotic/nonstenotic side) greater than 2.0 correctly predicted a favorable surgical result in all cases. Peripheral plasma renin activity was greater than normal in 65 percent of good responders, in 50 percent of fair responders and in one nonresponder. The prognostic accuracy of a pressure gradient greater than 40 mm Hg was 78 percent; no patient with a gradient of less than 40 mm Hg benefited from surgery. An increased juxtaglomerular cell count on the affected side predicted a successful operative result in 88 percent, as did increased granularity in 85 percent of cases. Renal venous renin ratio correlated positively (r =0.738, P less than 0.001) with the pressure gradient across the stenosis. The renal venous plasma renin activity of the affected side also correlated positively (r = 0.771, P less than 0.001) with the absolute count of granular cells in the juxtaglomerular apparatus. Plasma renin activity in both renal veins is the most reliable predictor of operative outcome. The addition of juxtaglomerular cell count or pressure gradient across the stenosis increases prognostic accuracy only slightly. The close mutual correlations between renal venous renin ratio, pressure gradient and juxtaglomerular cell count support the experimental evidence of a causal relation between the hemodynamic effects of the arterial lesion and the humoral and histologic changes observed in hypertension with renal arterial stenosis.  相似文献   
56.
To examine the role of neural and humoral factors in the control of coronary vasoactivity in conscious animals in which the complicating effects of general anesthesia and recent surgery were absent, dogs were instrumented with miniature pressure gauges in the aorta and left ventricle to measure aortic and left ventricular pressures and with flow probes in the left circumflex coronary artery to measure coronary blood flow. Several weeks after recovery from operation, experiments were conducted in the conscious dogs. Stimulation of the carotid chemoreceptor reflex elicted a biphasic response; initially striking reflex coronary vasodilation was observed: Coronary blood flow tripled even after changes in metabolic factors were minimized by pretreatment with propranolol. The chemoreceptor reflex coronary vasodilation was mediated both by cholinergic activation and withdrawal of alpha-adrenergic tone. The second phase of the response involved an increase in coronary vascular resistance, associated with elevated arterial pressure and an absolute reduction in coronary blood flow and coronary sinus oxygen content. The later period of coronary vasoconstriction was abolished by alpha-adrenergic blockade. Intravenous infusion of the alpha-adrenergic agonist methoxamine increased mean arterial pressure by 65 ± 5% and total coronary vascular resistance by 92 ± 14%. To determine whether the large coronary arteries were also under autonomic control, the dogs were instrumented with a pair of ultrasonic crystals on opposing surfaces of the left circumflex coronary artery to measure its diameter directly and continuously. Methoxamine reduced coronary cross-sectional area substantially, thereby constricting large coronary arteries and resistance coronary vessels. Thus, while the coronary arteries are regulated by changes in myocardial metabolic demands, they are also responsive to changes in neural stimuli. The most striking changes were observed with augmentation and withdrawal of alpha-adrenergic constrictor tone, which appear to be important in the control of large as well as small coronary vessels.  相似文献   
57.
Gated cardiac scanning was used to evaluate the hemodynamic effects of encainide in 19 patients (1 woman) with complex ventricular arrhythmia and depressed left ventricular (LV) function (ejection fraction less than 45%). Patients were 36 to 80 years old (average 61). All were candidates for long-term encainide therapy after having failed with currently available antiarrhythmics. Sixty-three percent had congestive heart failure before they received encainide. All were evaluated in the hospital before encainide therapy by a gated cardiac scan performed at least 3 days after discontinuing all antiarrhythmic drugs. Patients received oral encainide in doses of 75 to 200 mg. Gated cardiac scans were repeated 1 to 2 weeks later when an 80% reduction in frequency of premature ventricular complexes was observed on a 24-hour Holter recording. No patient had worsening of congestive heart failure during encainide therapy. Encainide did not significantly affect ejection fraction, which averaged 22 +/- 10% before and 25 +/- 14% (SD) after encainide (difference not significant [NS]). Other hemodynamic variables, including heart rate, blood pressure, stroke volume and end-diastolic volume, remained unchanged during encainide therapy. Digoxin blood levels in 10 patients averaged 1.04 +/- 0.43 before and 1.22 +/- 0.47 mg/ml (NS) during encainide therapy. Thus, encainide given orally in clinically effective doses does not appear to have significant hemodynamic effects in patients with ventricular arrhythmia and depressed LV function.  相似文献   
58.
59.

Objective

Determine human smoked (HS) cigarette yields of tar and nicotine for smokers using their own brand in their everyday environment.

Method

A robust, filter analysis method was used to estimate the tar and nicotine yields for 784 subjects. Seventeen brands were chosen to represent a wide range of styles: 85 and 100 mm lengths; menthol and non-menthol; 17, 23, and 25 mm circumference; with tar yields [Federal Trade Commission (FTC) method] ranging from 1 to 18 mg. Tar bands chosen corresponded to yields of 1–3 mg, 4–6 mg, 7–12 mg, and 13+ mg.

Results

A significant difference (p < 0.0001) in HS yields of tar and nicotine between tar bands was found. Machine-smoked yields were reasonable predictors of the HS yields for groups of subjects, but the relationship was neither exact nor linear. Neither the FTC, the Massachusetts (MA) nor the Canadian Intensive (CI) machine-smoking methods accurately reflect the HS yields across all brands. The FTC method was closest for the 7–12 mg and 13+ mg products and the MA method was closest for the 1–3 mg products. The HS yields for the 4–6 mg products were approximately midway between the FTC and the MA yields. HS nicotine yields corresponded well with published urinary and plasma nicotine biomarker studies.  相似文献   
60.
松塔化学成分及生物活性的研究进展   总被引:3,自引:0,他引:3  
近年来,国内外学者对松塔的化学成分及生物活性开展了大量的研究工作,发现松塔中含有萜类、木质素类、多糖等多种化学成分,并具有抗肿瘤、抗病毒、抗菌、增强免疫力等生物活性,具有重要的药物开发前景。现就其化学成分及生物活性予以综述,以期对松塔的进一步研究开发提供理论基础。  相似文献   
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