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71.
It is unclear whether single and combined pharmacologic inhibition of the renin-angiotensin-aldosterone system have similar effects on endothelial function and blood pressure (BP). The authors evaluated 63 hypertensive patients divided into 4 groups (hydrochlorothiazide 25 mg/d; irbesartan [IRBE] 150 mg/d; quinapril [QUIN] 20 mg/d; or IRBE 150 mg/d + QUIN 20 mg/d) and 25 healthy normotensive subjects (normal) followed for 12 weeks. Endothelium-dependent dysfunction measured as flow-mediated dilation at Weeks 0 and 12 were: normal, 11.5%±2.4% vs 13.5%±2.0%; hydrochlorothiazide, 7.3%±2.0% vs 12.8%±3.1%; QUIN, 7.2%±2.8% vs 13.2%±2.1%; IRBE, 7.1%±2.8% vs 13.0%±2.9%; and IRBE + QUIN, 7.5%±1.9% vs 12.8%±3.0%. Nitroglycerin-mediated responses were: normal, 26.0%±1.9% vs 24.0%±2.5%; hydrochlorothiazide, 17.0%±2.2% vs 18.3%±2.6%; QUIN, 17.8%±3.2% vs 23.4%±3.0%; IRBE, 16.8%±3.6% vs 24.7%±2.0%; and IRBE + QUIN, 17.3%±3.0% vs 25.1%±2.5%. Antihypertensive therapy restored BP to normal and improved the endothelium-dependent and -independent dysfunction after renin-angiotensin-aldosterone system blockade. In a further finding, the combined effect of angiotensin-converting enzyme inhibition and angiotensin II type 1 receptor blockade was not superior to the action of either of these treatments separately.  相似文献   
72.
73.
The aim of this research was to quantify sleep problems in patients suffering from Parkinson's disease by means of the new Parkinson's Disease Sleep Scale (PDSS) and to correlate such problems with the possible influence of current drug treatment. A total of 70 patients (36 men and 34 women) with a diagnosis of Parkinson's disease were enrolled. Their mean age was 69.7 +/- 8.2 years, and duration of disease was 7.4 +/- 4.8 years. All patients completed the PDSS and the Unified Parkinson's Disease Rating Scale (UPDRS Parts I-IV). Drug consumption and doses were registered. The mean score on the PDSS scale was 109.23 +/- 19.75 and on the UPDRS III scale was 25.24 +/- 11.35. The lowest scores were obtained in Item 3 (sleep fragmentation): 5.53 (2.46); and in Item 8 (nocturia): 5.75 (2.91). There was a weak correlation between the PDSS and UPDRS III (cc = -0.355, P = 0.003), PDSS and UPDRS I (cc = -0.272, P = 0.02), and PDSS and UPDRS IV (cc = -0.416, P < 0.001). Motor conditions, mental state, and drug complications influence sleep quality. Although this effect was significant, it was not of a great magnitude. Dopaminergic drugs did not increase daytime sleepiness. As a whole, sleep quality in patients who took dopaminergic agonists did not differ from that of patients who took levodopa in monotherapy.  相似文献   
74.
BACKGROUND: Some skin carcinomas may be very aggressive. Increased expression of the protein p53 has been associated with tumor aggressiveness. In this study, p53 expression was evaluated in basal cell carcinomas (BCC) and squamous cell carcinomas (SCC) with skull base invasion, and was compared to tumors with good outcome. STUDY DESIGN AND SETTING: Expression of p53 was immunohistochemically analyzed and it was reported as present or absent in 24 BCC and 11 SCC with skull base invasion. Control group (good outcome) included 23 BCC and 10 SCC. RESULTS: Expression of p53 was noted in 70.83% of BCC with skull base invasion, compared to 43.48% in the control group (P = 0.058). Regarding SCC, p53 positivity was noted in only 9.09% of SCC with skull base invasion, compared to 40.00% in the control group (P = 0.149). CONCLUSIONS: In this study, p53 expression was more common among BCC with skull base invasion, compared to controls with good outcome, and the difference was considered marginally significant. This proportion was reversed in SCC, but the difference was not statistically significant. EBM rating: B-3b.  相似文献   
75.
Current knowledge on the anatomy of area 3a of the cat mainly derives from the cyto- and myeloarchitectonic study of Hassler and Muhs-Clement (J Hirnforsch 6:377, 1964). Previous investigations in the cat had failed to identify a cortical region comparable to monkey's area 3a. In the present study, Nissl, myelin, acetylcholinesterase, and cytochrome oxidase staining techniques were applied to coronal and sagittal serial sections of the cat brain. Area 3a appears as a slender band of cortex between areas 4 and 3b, and in Nissl-stained sections it is mainly characterized by an attenuated granular layer IV, overlying a thin layer V with pyramidal cells of various sizes, including a few large ones. These cytoarchitectonic features are sufficient to differentiate area 3a from neighboring areas, although the borders between them are not sharp in many cases. After the Nissl staining, the acetylcholinesterase staining proved to be the most helpful in defining the structure and borders of area 3a. Acetylcholinesterase staining was dense in layer I (in contrast with a lighter staining of outer layer I in area 4), and light in layers II and IIIa, changing to moderate in IIIc and IV (a pattern which is accentuated in area 3b). Myelin and cytochrome oxidase techniques also yielded differential staining patterns of area 3a and neighboring areas 4 and 3b, although the borders were not easily drawn with these techniques. Whereas our cyto- and myeloarchitectonic findings were comparable to those of Hassler and Muhs-Clement ('64) and applied well to area 3a in the convexity of the hemisphere, we found that most of the area 3a described by these authors in the medial face of the hemisphere had a number of distinguishing architectonic (as well as connectional and physiological) features which enabled us to define it as a separate area (7m). The techniques we used to delineate area 3a are compatible with most current procedures of histo- and immunohistochemical staining of the brain, and may also provide valuable supporting data for electrophysiological studies.  相似文献   
76.
n-Hexane neuropathy was studied in 20 workers exposed for prolonged periods to this solvent, and with urinary 2, 5-hexanedione concentrations exceeding the biological exposure index recommended by the American Conference of Governmental Industrial Hygienists (5 mg/L) with a mean of 11.02 mg/L (range 5.3—24.2 mg/L). Although neurological examination did not detect significant anomalies in any of the patients, and the conduction velocity and F waves of all the nerves tested were normal, neurographic studies revealed significant differences in the amplitude of sensory nerve action potentials (SNAP) recorded from the sural (mean 14.0 μV), median (mean 17.3 μV), and ulnar (mean 7.9 μV) nerves when compared with normal values from healthy adults of the same age range, examined under identical conditions. The amplitude of the SNAP in sural and median nerves correlated significantly with the number of years worked. The notable decrease in mean amplitude of the SNAP appeared to reflect the primary neurotoxic effects of 2,5-hexanedione. © 1994 John Wiley & Sons, Inc.  相似文献   
77.
Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.  相似文献   
78.
With a mean follow-up of 3 (1-6) years, we report on 21 patients who underwent multiple level cervical fusion, using autologous iliac crest grafts. Dis-cectomies were performed in 14 patients and cor-pectomies in another 7. Instrumentation was used in all patients with colectomies and in 2 patients who underwent 2-level and 3-level discectomies. Non-union occurred in 1 patient at 1 level. Graft displacement requiring reoperation was observed in 2 patients with massive corpectomies, in 1 of them as a consequence of trauma. In both patients complete bony fusion was obtained after reoperation and no other complications were observed. We conclude that the success rate with multiple-level fusion is comparable to that of single-level fusion when adequate fixation is achieved.  相似文献   
79.

Background  

The GRADE method represents a new approach to grading the quality of evidence and strength of recommendations in the preparation of Clinical Practice Guidelines (CPG). In the context of a pilot study to assess the implementability of the system in Spain, we considered it relevant to gain an insight into the significance of the perceptions and attitudes expressed by the actual experts participating in the system try-out.  相似文献   
80.
OBJECTIVE: The primary goal of this study was to evaluate the validity of the North American-European Consensus Committee (NAECC) definition for acute respiratory distress syndrome (ARDS) in pediatric patients. A secondary aim was to evaluate the threshold value for the PaO2/FiO2 ratio, used to determine which pediatric patients have ARDS. DESIGN: Retrospective cohort study. SETTING: Pediatric intensive care unit. PATIENTS: Pediatric intensive care unit patients who required mechanical ventilation, died, and underwent autopsy between January 1, 1996, and December 31, 2002 (n = 34). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Clinical and chest radiograph information was collected retrospectively through chart review using a standardized data collection tool. Data included the criteria specified in the NAECC definition of ARDS and demographic information. We calculated the sensitivity, specificity, positive predictive value, negative predictive value, and likelihood ratio of clinical diagnosis of ARDS compared with a pathologic diagnosis. The threshold value of PaO2/FiO2 was identified by plotting receiver operating characteristics curves and comparing the areas under the curves. The NAECC definition yielded a sensitivity of 80.7% (95% confidence interval 60-92%), specificity of 71.4% (95% confidence interval 30-95), positive predictive value of 91.3% (95% confidence interval 70-98), negative predictive value of 50.0% (95% confidence interval 20-78), and likelihood ratio of 2.82. A PaO2/FiO2 <150 had a slightly higher (but not significantly different) specificity for ARDS than a value >200 (71% vs. 86%, p = .15) without changing sensitivity. CONCLUSIONS: Our study suggests the need for further research with larger number of children to identify an optimal Pao2/Fio2 threshold for identifying ARDS in this population.  相似文献   
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