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11.
PURPOSE: To investigate ictal muscular phenomena characterizing symptomatic infantile spasms (ISs) and their relation to ictal EEG. METHODS: Four children with severe encephalopathy, neurologic impairment, and refractory ISs related to different dysplastic lesions, underwent videopolygraphic recordings collecting surface electromyogram (EMG) activity from several cranial and limb muscles to evaluate the pattern of muscular recruitment, duration, and side-to-side asymmetry of ISs. Acquired data were stored for off-line analysis by a computerized polygraphic system. RESULTS: Spasms were characterized by a complex pattern of muscular activation. A constant or rostrocaudal propagation pattern was lacking in all patients. Intervals between the onset of EMG activity in different muscles in each spasm were very long: 相似文献   
12.
VEPs were examined in ALL patients in order to test their usefulness in the detection of early and late CNS changes due to combined cranial X-irradiation and chemotherapy. The results suggest that: a)in patients free from self limited somnolence syndrome and visual symptoms, the VEP latency may be increased, probably because of early subclinical CNS changes due to cranial irradiation. b)late CNS changes (detected by routine neurological examination, EEG and CAT) seem to be correlated with increased VEP latency, even in the absence of visual symptoms.  相似文献   
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14.
Ultrasonic tissue characterization of the myocardium in anorexia nervosa   总被引:2,自引:0,他引:2  
AIM: To determine the systodiastolic variations in the integrated backscatter (IBS) signal of the myocardium in patients with anorexia nervosa. METHODS: 25 young women (aged 22.4 +/- 4.3 y) with overt anorexia nervosa, compared with 25 age-matched thin and 25 age-matched control women with body mass index >20 kg m(-2), underwent either conventional two-dimensional echocardiography or analysis of IBS cyclic variations. RESULTS: Compared with thin and control subjects, anorectic patients showed reduced left ventricular mass (LVM: 82.9 +/- 17.1 vs 119.9 +/- 13.8 and vs 126.12 +/- 16.4 g, p < 0.0001; LVM indexed 21.4 +/- 3.3 vs 29.4 +/- 2.5 and vs 31.2 +/- 3.1 g m(-2.7), p < 0.0001), and IBS cyclic variations (septum: -0.49 +/- 2.18 vs 6.86 +/- 1.3 and vs 6.61 +/- 1.74 dB p < 0.0001; posterior wall: 2.77 +/- 2.12 vs 7.15 +/- 2.12 and vs 7.48 +/- 2.23 dB, p < 0.01). CONCLUSION: Anorexia nervosa is associated with a significant reduction in the cyclic variation in IBS, which is also related to left ventricular hypotrophy. Ultrasonic tissue characterization could give an objective approach for the detection of myocardial structural properties and represent a preclinical index of myocardial dysfunction in anorexia nervosa.  相似文献   
15.
OBJECTIVES: To evaluate the degree of QT dispersion in a group of young women in the starvation phase of anorexia nervosa (AN) and its relation to left ventricular (LV) mass. STUDY DESIGN: Sixteen patients with self-induced starvation were matched with 16 women of normal weight and 16 constitutionally thin women (body mass index <20 kg/m2). Starving patients and control patients underwent an electrocardiogram and echocardiogram. QT intervals were measured from surface electrocardiograms and QT dispersion was defined as the difference between maximum QT and minimum QT occurring in any of the 12 leads. RESULTS: LV-chamber mass was significantly less in women with AN than in thin and normal-weight women. QT dispersion was significantly greater in AN than in the thin and control groups (QT dispersion: 50 +/- 14 vs 34 +/- 9 and 37 +/- 11 ms, P <.001; QT interval dispersion corrected for heart rate: 49+12 vs 34 +/- 9 and 36 +/- 7 ms, P <.01, respectively). A significant relation between QT dispersion and LV-mass index (r = -0.726, P <.01), and between QTc dispersion and LV mass index (r = -0.693, P < 0.01) were found only in the patients with AN. CONCLUSION: Starving patients show an increased QT dispersion related to reduced LV mass. This result could represent a useful indicator of arrhythmic risk and sudden death in AN.  相似文献   
16.
QT dispersion in elderly athletes with left ventricular hypertrophy   总被引:1,自引:0,他引:1  
The purpose of this study was to examine the QT dispersion in elderly endurance athletes with left ventricular (LV) hypertrophy. Sixteen athletes (males, mean age 67.6 +/- 4.5 years) with mild to moderate LV hypertrophy, were compared with 16 age-matched hypertensive patients with similar degree of LV hypertrophy and 16 age-matched healthy sedentary controls. All the participants underwent echocardiogram and 12-lead electrocardiogram. QT dispersion was defined as the difference between maximum and minimum QT intervals in the different leads. QT dispersion was corrected (QTc) for heart rate according to Bazett's formula. The results showed in athletes and hypertensive patients comparable LV mass (258.2 +/- 14.2 vs. 262.4 +/- 16.8 g, ns), which was significantly higher than that of controls (p < 0.001). Trained subjects had QT dispersion (38.6 +/- 10.2 ms) and QTc dispersion (39.4 +/- 11.3 ms) significantly lower than hypertensive patients (QT dispersion: 68.4 +/- 11.4 ms; QTc dispersion: 72.2 +/- 8.4, p < 0.001) and comparable with controls (QT dispersion: 44.3 +/- 8.4 ms; QTc dispersion: 46.2 +/- 6.2 ms, ns). In conclusion, in elderly athletes training-induced myocardial hypertrophy was characterized by a QT dispersion significantly lower than hypertensive myocardial hypertrophy. This could provide a simple and inexpensive screening method for differentiating physiologic from pathologic myocardial hypertrophy in elderly subjects.  相似文献   
17.
AIM: Regular exercise is a key component of cardiovascular risk prevention strategies, because it is associated with a variety of beneficial metabolic and vascular effects that reduce mortality and the incidence of cardiovascular adverse events. Endothelium plays an important role in the local regulation of vascular tone and structure, mainly by nitric oxide (NO) synthesis and action. Aim of the present study was to evaluate in elderly athletes the effect of regular aerobic exercise on arterial blood pressure (BP) and on endothelium-dependent flow-mediated dilation (FMD) of the brachial artery. METHODS: The study population included 30 male subjects (mean age 65.6+/-5.6 years), who had practiced endurance running at a competitive level for at least 40 years, and 28 age- and sex-matched subjects (mean age 64.5+/-4.5 years) with sedentary lifestyle and free of cardiovascular disease. Athletes and control subjects underwent standard 12-lead ECG, clinic BP, 24-h ambulatory BP monitoring and endothelium-dependent FMD and endothelium-independent response to glyceryl trinitrate (GTN), 400 microg, in the brachial artery by high-resolution ultrasonography. RESULTS: Systolic clinic and ambulatory 24-h BP were significantly lower in the athletes, than in the controls (P<0.001, respectively). Systolic and diastolic 24-h BP variability, when assessed either by the standard deviation (S.D.), or by the coefficient of variation (CV), were also significantly lower in the athletes (P<0.01). The athletes also had a lower 24-h, day-time and night-time heart rate (HR) (P<0.01), as well as a lower HR variability (P<0.01). As regards circadian BP change, the %Delta was statistically significant greater in athletes (P<0.05). Elderly athletes showed higher FMD than elderly sedentary subjects (P<0.001), whereas no differences were shown in the response to GTN. CONCLUSIONS: Our results, suggest that long-term physical activity can counteract the age-related endothelial dysfunction that characterizes sedentary aging, preserving the capacity of the endothelium-dependent vasodilation and reduces BP values improving arterial pressure control.  相似文献   
18.
Health status, functional status, and social influences were analyzed as risk factors associated with mortality in 1201 elderly subjects (70–75 years old), living in the center of Brescia, Northern Italy, followed up for three years.Mortality was positively associated with degree of impairment in health status, functional status, and mental status as measured by cognitive function and mood depression. Among social conditions no relation was found between mortality and living alone, education, or income, while a significant inverse relationship has been found between mortality and activities. In defining risk factors of mortality in aged people not only health status and cognitive function have to be taken into account but also social activities; these latter may act as protective factors buffering the organism from the effects of noxious stimuli.Paper originally presented at the XIVth International Congress of Gerontology, Acapulo, Mexico 18–23 June 1989.  相似文献   
19.
Antiepileptic drugs are known to result in visual disturbances. A number of antiepileptic drugs have recently been reported to result in various abnormalities of vision, particularly deficiencies in visual fields and color vision. Moreover, there has been a marked improvement in the diagnosis and understanding of the pathophysiology of visual disturbance. This review collects evidence for visual adverse effects induced by the older antiepileptic drugs (barbiturates, benzodiazepine, carbamazepine, valproic acid, ethosuximide, and phenytoin) and the newer ones (vigabatrin, topiramate, tiagabine, levetiracetam, lamotrigine, gabapentin, felbamate, and oxcarbazepine).  相似文献   
20.
BACKGROUND: Frontal lobe epilepsy (FLE) is a type of epilepsy that is difficult to treat and there are few studies about the use of topiramate (TPM). AIM OF THE STUDY: To evaluate the efficacy and tolerability of TPM monotherapy in FLE. METHODS: The study group consisted of 55 (33 male; 22 female) patients. TPM was administered as a first drug (n = 16) or converted after previous treatment (n = 39). All patients were followed every 3 months for at least 1 year. The patients were subdivided into two groups: 'newly diagnosed' patients and 'difficult-to-treat' patients. RESULTS: Overall, all patients completed the 1-year study. At the end of follow-up, 10 patients showed disappearance of seizures and 33 patients showed improvement in seizure frequency. In particular, among the newly diagnosed patients 6/16 patients showed complete cessation of seizures and 5/16 patients showed very good response; in the other group, 4/39 patients showed complete cessation and 4/39 patients showed a very good response. No patients of both groups had worsening of seizures. No treatment-limiting adverse events associated with TPM were reported. CONCLUSIONS: TPM is effective in newly diagnosed patients with FLE; TPM can be considered for the treatment of FLE.  相似文献   
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