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61.
62.
Cardiac Rehabilitation in Patients with Rate Responsive Pacemakers   总被引:1,自引:0,他引:1  
This study investigated the suitability of our oxygen pulse reserve (OPR) method for tailoring parameters of rate responsive pacemakers and planning aerobic rehabilitation programs. We selected 11 patients, NYHA Classes I-III (7 males and 4 females; mean age 60 years, range 18–83), with rate responsive pacemakers implanted for high degree AV block and chronotropic incompetence. Five pacemakers had activity sensors, 4 had temperature sensors, and 2 had dual sensors. All patients underwent a cardiopulmonary stress test (CPX). We determined anaerobic threshold time (ATT), VO2/AT, total exercise time (TET), VO2 Max, and VO2AT/VO2 Max. OPR (mL-O2/beat) was calculated for each patient using the formula OPR = (VO2Max - VO2 resting)/(HR Max - HR resting). During CPX, this slope was used as the rate response tailoring guideline by comparing the mL-O2/beat equation and the pacing rate. Rate response settings were modified until the optimal relationship between theoretical and paced rate was obtained. The work protocol yielded rate response settings capable of providing pacing rates within ± 10 beats of the theoretical values. Data relating to theoretical and measured rates have been analyzed statistically. Patients underwent an aerobic rehabilitation program that followed the American College of Sports Medicine guidelines. Pacing rate at the anaerobic threshold was considered the border for an aerobic workload. After 2–7 months, all patients showed an evident improvement in ATT (92%), VO2/AT(48%), TET(49%), VO-,Max (23%), and VO2 AT/VO2 (21%). Particularly, two patients improved from Weber Class C to A, and three improved from C to B. At each CPX step, the mean values of pacing rate and theoretical rate almost overlap, and the relevant coefficients suggest an excellent correlation (P < 0.001). Our OPR method for tailoring rate response provides the basis for an effective rehabilitation program with functional advantages for patients.  相似文献   
63.
BACKGROUND: Angiosarcoma (AS) is a rare, invasive malignancy originating from endothelial cells caused by many different clinical situations. AS following radiotherapy for breast cancer after conservative surgery is a rare but well-known association. OBJECTIVE: The aim of this article is to describe a case of AS after breast conserving surgery and to review the literature to date. RESULTS: We report the case of an 84-year-old woman who developed AS four years after she was subjected to quadrantectomy for invasive ductal cancer, followed by 30 tangent field radiotherapy sessions. She presented with a one-month history or red papular skin eruptions on the operated breast. Skin lesions were submitted for biopsy, and they were positive for AS. The patients was subjected to surgical excision of the remaining breast including all AS lesions. She is alive with no evidence of disease after 10 months follow-up. CONCLUSION: Post-radiotherapy AS is rare neoplasm, but it should be considered in the case of patients with red lesions after breast conserving surgery and adjuvant radiotherapy.  相似文献   
64.
In an investigation of the role of keratinocytes in the pre-immunological phase of contact allergy, we have studied the effect of paraphenylenediamine (PPD) on cell proliferation, membrane lipid peroxidation and the expression of the intercellular adhesion molecule 1 (ICAM-1). Because PPD undergoes rapid autoxidation in the culture medium, the effect of PPD-modified medium on keratinocyte proliferation and ICAM-1 expression was also examined. PPD at low concentrations (up to 10 micrograms/ml) and with low exposure times (0.5 h) enhanced keratinocyte proliferation, but at high concentrations and with longer exposure times resulted in cell stasis and toxicity. These effects and the enhanced membrane lipid peroxidation that was also observed can be ascribed to the production of superoxide and hydrogen peroxide by the autoxidation of PPD in the medium. At non-cytotoxic concentrations, PPD induced ICAM-1 expression on the keratinocytes. PPD-modified medium was also cytotoxic to the keratinocytes and induced ICAM-1 expression in non-cytotoxic concentrations. It appeared that superoxide and hydrogen peroxide were not responsible for the cytotoxicity. These results are consistent with the view that oxidative stress may be an essential part of the pre-immunological phase in the induction of allergic contact dermatitis.  相似文献   
65.
Objective: To study the correlation between heart sounds and peak endocardial acceleration (PEA) amplitudes and timings, by modulation of paced atrioventricular (AV) delay in recipients of dual chamber pacemakers.
Methods: Ten recipients of dual chamber pacemakers implanted for high-degree AV block were studied. Endocardial acceleration (EA) and phonocardiographic and electrocardiographic signals were recorded during performance of an AV delay scan in VDD and DDD modes.
Results: First PEA (PEA I) and first heart sound (S1) changed similarly with the AV delay. A close intrapatient correlation was observed between S1 and PEA I amplitudes in all patients (P < 0.0001). The interpatient normalized PEA I to S1 amplitudes correlation was r = 0.89 (P < 0.0001) in DDD mode, and r = 0.81 (P < 0.0001) in VDD mode. The mean cycle-by-cycle PEA I to S1 delay was −4.3 ± 22 ms and second PEA (PEA II) to second heart sound (S2) delay was −7.7 ± 15 ms.
Conclusions: A close correlation was observed between PEA I and S1 amplitudes and timings, and between PEA II and S2 timings. These observations support the hypothesis that PEA and heart sounds are manifestations of the same phenomena. EA might be a useful tool to monitor cardiac function.  相似文献   
66.
We described a 77‐year‐old patient, previously implanted with a dual‐chamber pacemaker later upgraded to a cardiac resynchronization therapy‐defibrillator (CRT‐D) device with an active‐fixation coronary sinus pacing lead, who underwent a transvenous mechanical extraction procedure for a device‐related systemic infection. All leads were removed successfully with a transvenous approach. With regard to the coronary sinus (CS) lead (Attain 4195 StarFix, Medtronic Inc., Minneapolis, MN, USA), manual traction was ineffective and extraction required long and challenging mechanical dilatation up to distal CS using either conventional sheaths or modified CS lead delivery. (PACE 2010; 34:e66–e69)  相似文献   
67.
Summary. Background: The aim of the current study was to perform two separate meta‐analyses of available studies comparing low‐molecular‐weight heparins (LMWHs) vs. unfractionated heparin (UFH) in ST‐elevation myocardial infarction (STEMI) patients treated (i) with primary percutaneous coronary intervention (pPCI) or (ii) with PCI after thrombolysis. Methods: All‐cause mortality was the pre‐specified primary endpoint and major bleeding complications were recorded as the secondary endpoints. Relative risk (RR) with a 95% confidence interval (CI) and absolute risk reduction (ARR) were chosen as the effect measure. Results: Ten studies comprising 16 286 patients were included. The median follow‐up was 2 months for the primary endpoint. Among LMWHs, enoxaparin was the compound most frequently used. In the pPCI group, LMWHs were associated with a reduction in mortality [RR (95% CI) = 0.51 (0.41–0.64), P < 0.001, ARR = 3%] and major bleeding [RR (95% CI) = 0.68 (0.49–0.94), P = 0.02, ARR = 2.0%] as compared with UFH. Conversely, no clear evidence of benefits with LWMHs was observed in the PCI group after thrombolysis. Meta‐regression showed that patients with a higher baseline risk had greater benefits from LMWHs (r = 0.72, P = 0.02). Conclusions: LMWHs were associated with greater efficacy and safety than UFH in STEMI patients treated with pPCI, with a significant relationship between risk profile and clinical benefits. Based on this meta‐analysis, LMWHs may be considered as a preferred anticoagulant among STEMI patients undergoing pPCI.  相似文献   
68.
Background: In the Endotak Reliance G defibrillating leads (Guidant Corporation, St. Paul, MN, USA), coils are covered with expanded polytetrafluoroethylene (ePTFE) to prevent tissue ingrowth. The aim of the study was to evaluate transvenous extraction performance, outcomes, and fibrotic adherences rate of ePTFE defibrillating leads in comparison to traditional non‐ePTFE cardiac defibrillator (ICD) leads. Methods: Seventeen consecutive ICD recipients (ePTFE Group A, 16 men, mean age 66 ± 12 years) with 17 Endotak Reliance G dual‐coil ICD leads (mean implantation time 23 ± 26 months) underwent a transvenous removal procedure. They were compared with two control groups, including 20 Sprint Quattro 6944 (non‐ePTFE Group B; Medtronic Inc., Minneapolis, MN, USA) and 36 Riata 1570 ICD leads (non‐ePTFE Group C; St. Jude Medical, St. Paul, USA). The indication for lead extraction was local infection in 35 patients (48%), sepsis in 24 patients (33%), and lead malfunction in 14 patients (19%). Results: In all groups, all leads were successfully and completely removed without major complications. Overall manual traction was effective in six patients (8%) and more effective in the ePTFE Group (29%) compared to Group B (0%) and Group C (3%) (P = 0.001). Sixty‐seven leads (92%) required mechanical dilatation by the venous entry site approach, with a shorter extraction time in the ePTFE Group (5 ± 11 min) compared to Group B (21 ± 22 min) and Group C (16 ± 22 min) (P = 0.003). ePTFE leads showed a lower rate of fibrotic adherences at the superior vena cava level (P = 0.01) without statistically significant differences in the other sites. Conclusions: ePTFE‐covered leads may be removed more easily and quickly than non‐ePTFE leads, requiring less frequently mechanical dilatation. (PACE 2010; 1376–1381)  相似文献   
69.
Incomplete Endothelialization of Left Atrial Appendage . We describe the case of a 74‐year‐old man with Rendu Osler Weber syndrome affected by permanent atrial fibrillation, who underwent percutaneous placement of a 24‐mm Watchman left atrial appendage system. After anticoagulation therapy dismissal, he had a transient ischemic attack (TIA). Therefore he underwent surgical removal of the device, ablation of atrial fibrillation with Maze IV procedure and biatrial reduction. Very interestingly, no significant endothelialization of the device was observed 10 months after implantation. In conclusion, this case is important because, to our knowledge, it is the first finding of Watchman device with lack of endothelialization. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1384‐1385, December 2012)  相似文献   
70.
Summary. The relation between parental moderate alcohol consumption and the risk of miscarriage was analysed using data from a casecontrol study in Milan between January 1987 and June 1988. Cases were 94 women who had two or more 'unexplained' miscarriages (after exclusion of genetic, endocrine and Miillerian factors) and without full-term pregnancies, admitted or referred to the First Obstetric and Gynecologic Clinic of the University of Milan. A total of 176 women admitted for normal delivery on selected days to the same university clinic and without previous miscarriages were chosen as controls. Compared with non-drinkers the risk of recurrent miscarriage was 0·9 for regular drinkers. The point estimates were 0·9 for women reporting one drink per day and 0·8 for those reporting two or more. Compared with non-drinkers, the relative risk estimates for drinking by fathers were slightly above unity, being 1·7 for less than three drinks and 1·4 for three or more drinks per day, but the trend in risk was not statistically significant.  相似文献   
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