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91.
Background and aimsDiabetes mellitus (DM) is a frequent comorbidity in ST-elevation-myocardial infarction (STEMI) patients and carries a higher risk of in-hospital mortality. We recently demonstrated that the higher in-hospital mortality of STEMI patients with DM, when compared to that of patients without DM, is mainly associated with their more frequent cardiac and renal dysfunction. These exploratory results prompted us to hypothesize that this higher risk in DM patients is mediated by their lower cardio-renal functional reserve.Methods and resultsWe included 5152 STEMI patients treated with primary angioplasty. By using an advanced statistical methodology (path analysis), able to clarify the putative causal paths between variables of interest, we reported that the higher in-hospital mortality of STEMI patients with DM is possibly caused by its adverse impact on cardio-renal function.ConclusionThis statistical approach allows to reinforce the well-known notion that DM is associated with an increased in-hospital mortality risk in STEMI and sheds lights on the causal relationship among DM, cardio-renal dysfunction, and higher in-hospital mortality. Whether the mortality gap between DM and non-DM patients with STEMI can be reduced by pharmacological strategies combining cardio-renal protective effects is an intriguing question that deserves an answer in the future.  相似文献   
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93.
We investigated the effects of arrows, eye gaze, and digits presented as irrelevant flankers in a line bisection task that was administered to 17 right brain damaged patients with or without left neglect. The rightward bias of neglect patients was selectively modulated by the direction of eye gaze and by the magnitude of two identical digits. The bisection error was shifted contralesionally by leftward-gazing eyes and "small" digits, whereas it was shifted ipsilesionally by rightward-gazing eyes and "large" digits. Therefore, the performance of neglect patients was influenced by task-irrelevant cues whose directional meaning was either explicitly represented (eye gaze) or related to the activation of a spatially oriented mental representation (digits). Regression analyses of the overall performance revealed that size of the rightward bias and error variability were predicted by neglect assessment scores across the entire sample of right brain damaged patients. The increased variability in line bisection performance is consistent with the "indifference zone" theory and it appears to be a subtle but stable marker of neglect.  相似文献   
94.
Nanohybrids for controlled antibiotic release in topical applications   总被引:1,自引:0,他引:1  
New polymeric composite materials containing a nanohybrid to be used for the controlled release of an antibiotic molecule, chloramphenicol succinate, have been formulated, prepared and characterised. The nanohybrid consists of a layered double hydroxide of Mg-Al hydrotalcite-type, in which the nitrate anions present in the host galleries were replaced with chloramphenicol succinate anions (CFS(-)) by a simple ion-exchange reaction. Different amounts of the hybrid material were incorporated in polycaprolactone and processed as films of 0.15mm thickness. The composite materials were analysed by X-ray diffractometry and thermogravimetry and their mechanical properties were determined. They showed properties even better than those of the pristine polymer. The release process of the antibiotic molecules was found to be very interesting and promising for tuneable drug delivery. It consists of two stages: an initial stage of a very rapid burst, in which a small fraction of drug is released; and a second stage that is much slower, extending for a longer and longer time. This behaviour is profoundly different and much slower than that of a sample in which the antibiotic molecule is directly incorporated into the polymeric matrix. The parameters influencing drug release have been individuated and discussed.  相似文献   
95.
The ovarian hormone estradiol regulates the expression of arginine vasopressin gene and the release of arginine vasopressin by magnocellular hypothalamic neurons. Magnocellular neurons express estrogen receptor β and are contacted by afferent neurons that express estrogen receptor α. In this study we have assessed the effect of selective ligands for estrogen receptors to determine the subtype of estrogen receptor involved in the regulation of arginine vasopressin immunoreactivity in the supraoptic and paraventricular nuclei of ovariectomized rats. The volume fraction occupied by arginine vasopressin immunoreactive material was significantly increased in both nuclei in the animals treated with estradiol compared to the animals injected with vehicle. A similar result was obtained with an estrogen receptor α selective agonist. In contrast, the administration of an estrogen receptor β selective agonist did not significantly affect arginine vasopressin immunoreactivity. This finding suggests that estradiol may regulate arginine vasopressin levels on the supraoptic and paraventricular nuclei by acting on afferent neurons expressing estrogen receptor α.  相似文献   
96.
Dead space/tidal volume ratio (VD/VT) evaluation is currently performed in patients with respiratory and cardiac disorders, and includes measurement of arterial CO2 partial pressure (PaCO2). PaCO2 is generally derived from either PETCO2 (end-expiratory CO2 pressure) or PJCO2 (calculated as PJCO2 = 5.5 + 0.9 PETCO2 - 2.1 VT). The applicability of these methods may be questionable in chronic heart failure due to its frequent association with lung dysfunction. In 63 patients with congestive heart failure, the authors compared PaCO2 versus PETCO2 and PJCO2 and VD/VT measured with PaCO2 versus VD/VT estimated with PETCO2 (estimation 1) or PJCO2 (estimation 2). Comparisons were made at rest, at submaximal exercise, and at peak exercise. Considering all 326 measurements, there was a strong correlation, but not an identity, between PaCO2 and PETCO2 (PaCO2 = 7.25 + 0.80 PETCO2, r = .84, P < .0001) and between PaCO2 and PJCO2 (PaCO2 = 6.18 + 0.84 PJCO2, r = .85, P < .0001). Results were comparable concerning PaCO2 versus PJCO2. Measured VD/VTs also strongly correlated with estimated VD/VTs (VD/VT measured = -0.03 + 1.11 VD/VT [estimation 1], r = .90, P < .0001, and VD/VT measured = 0.03 + 0.92 VD/VT [estimation 2], r = .90, P < .0001). However, only at rest and, solely for estimation 1, at submaximal exercise were the slopes and y intercepts of measured versus estimated VD/VT not different from 1 and 0, respectively; in this regard, lung dysfunction was more influential than the severity of cardiac failure. Although PaCO2 strongly correlates with PETCO2 and PJCO2, these measurements may not be reliable for a noninvasive calculation of VD/VT in chronic congestive heart failure.  相似文献   
97.
The root displacement into the maxillary sinus could be a complication of oral surgery in the upper jaw. In these cases, the root removal is needed in order to avoid the occurrence of sinus pathologies. Piezosurgery techniques could assure a safer management of such complications, because of the clear surgical visibility and the selective ability of cut. The aim of this article is to present a case of oral surgery complication (root displacement in the right maxillary sinus), in which piezosurgery technique helped for a correct and safe clinical management, allowing to reduce the soft tissue damage.  相似文献   
98.
99.
Hypertension and type 2 diabetes are associated with increased aortic pulse wave velocity (PWV), a measure of aortic stiffness and a powerful risk factor for cardiovascular events. The association of hypertension with type 2 diabetes may obscure the degree to which diabetes rather than hypertension contributes to an elevated PWV. The objective of this study was to determine whether the presence of type 2 diabetes is associated with an elevated PWV compared with nondiabetic subjects matched for mean arterial blood pressure. PWV was determined by measuring carotid to femoral transit time using applanation tonometry in 186 subjects (104 women) with (n=93) and without (n=93) type 2 diabetes. Diabetic and nondiabetic subjects were matched for age and mean arterial pressure (to +/-5 years and 5 mm Hg, respectively). PWV was strongly correlated with age and mean arterial blood pressure (R=0.59 and 0.29 respectively, each P<0.0001). PWV increased significantly more with age in women with diabetes (slope of regression line+/-SE: 0.19+/-0.03 m x s(-1) x year(-1)) than in nondiabetic women (0.08+/-0.02 m x s(-1) x year(-1), P<0.01 for difference). In men, however, the age-related increase in PWV was similar in diabetic (0.15+/-0.03 m x s(-1) x year(-1)) and nondiabetic subjects (0.13+/-0.03 m. s(-1) x year(-1), P=NS). The interaction of diabetic status with age and with sex was significant (P=0.01). Type 2 diabetes is associated with a greater age-related stiffening of the aorta in women compared with men, and this is not explained by hypertension.  相似文献   
100.
Background: Biliopancreatic diversion (BPD) by Scopinaro's method is an operation advocated by some surgeons as an effective treatment for morbid obesity. Methods: Between February 1995 and April 1997 we performed BPD by Scopinaro's method on 50 patients with morbid obesity (23 males), average age 41.4 years (range 20-63 years), average body weight 135.08 kg (range 89-256 kg), mean body mass index (BMI) 50.65 kg/m2 (range 37.01-81.56 kg/m2). Results: In all cases a gradual decrease in weight was obtained [mean BMI at 1 month: 44.8 kg/m2, at 6 months (31 patients): 35.09 kg/m2, at 1 year (23 patients): 31.36 kg/m2, at 18 months (14 patients): 29.89 kg/m2 and at 2 years (5 patients): 29.27 kg/m2]. At the same time a significant improvement in the pathological conditions associated with morbid obesity was observed. The patients were able to suspend oral antihypertensive and antidiabetic therapy as these parameters spontaneously returned to normal values by the sixth postoperative month; all cases showed a marked reduction in hypercholesterolemia and hypertriglyceridemia. Postoperative complications were: one death (2%) on the third day due to heart failure; two late intestinal occlusions (4%); one acute dilatation of the stomach (2%); one peritonitis caused by early dehiscence of the anastomosis (2%); five anastomotic ulcers (10%); two cases of protein malnutrition (4%). Conclusions: BPD by Scopinaro's method is a bariatric procedure which is technically complex. However is it safe and reproducible and it induces a substantial weight loss.  相似文献   
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