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71.
Stroke is major public health problem leading to increased morbidity and mortality. Modifiable risk factors for stroke include hypertension, diabetes, atrial fibrillation, dyslipidemia, smoking, and alcohol abuse. Among these risk factors, diabetes and hypertension are rapidly growing epidemics leading to a substantial increase in cardiovascular disease and stroke. In this review, the authors discuss the risk factors for stroke with emphasis on the diabetic and hypertensive population, highlighting the interventions that have been shown to decrease stroke risk in this patient population.  相似文献   
72.
OBJECTIVE: This study was undertaken to assess whether estrogen therapy (ET) reduces the risk of cognitive decline in women with cerebrovascular disease. STUDY DESIGN: We conducted a randomized, double-blind trial of estradiol 17beta versus placebo for secondary stroke prevention in 664 postmenopausal women with a recent stroke or transient ischemic attack. The Mini-Mental State Examination (MMSE) and 5 domain measures were obtained at baseline and exit. RESULTS: Among 461 women withdrawn alive without stroke, ET did not have a significant effect on cognitive measures after an average of 3 years (relative risk of MMSE decline: 0.74, 95% CI, 0.49-1.13). In women with normal MMSE at entry, estrogen was associated with less decline (relative risk, 0.46, 95% CI, 0.24-0.87). CONCLUSION: In this study, estradiol did not have significant effects on cognitive measures. However, in women with normal function at baseline, there may be a benefit for ET in reducing the risk for cognitive decline.  相似文献   
73.
74.
Neuroblastoma is extremely rare in adults. Advances in classification and therapy have been recently made by an analysis of pediatric tumors. We present the case of a 39-year-old man who had Stage 1 neuroblastoma with unfavorable histologic features that was treated with surgery only. Neuroblastoma should be considered as a diagnosis for adult patients with a suprarenal mass and, if confirmed, neuroblastoma in adults should be classified and treated according to pediatric guidelines.  相似文献   
75.
Youssef AS  Abdel Aziz KM  Kim EY  Keller JT  Zuccarello M  van Loveren HR 《Neurosurgery》2004,54(5):1181-7; discussion 1187-9
OBJECTIVE: The carotid-oculomotor window remains the traditional deep window in the exposure of aneurysms of the upper basilar artery. Although several techniques have been described to expand this window, few morphometric studies document either the degree of its expansion or its contribution to the exposure of the basilar artery. We review the microsurgical anatomy of the carotid-oculomotor window, describe expansion techniques, and analyze morphometrically the contribution of each step (i.e., extradural anterior clinoidectomy, mobilization of the internal carotid artery [ICA], and posterior clinoidectomy) to the expansion of the window and/or exposure of the artery. METHODS: Ten formalin-fixed, alcohol-preserved, cadaver heads injected with pigmented silicone were prepared for bilateral dissection. The vertebrobasilar system was injected with pigmented silicone mixed with barium (1:1), rendering it radiopaque. After completing a frontotemporal-orbitozygomatic craniotomy, we performed dissection in two stages: Stage I consisted of a conventional transsylvian exposure of the upper basilar artery through the carotid-oculomotor window; and Stage II added anterior clinoidectomy, ICA mobilization, and posterior clinoidectomy. A clip was applied to the lowest accessible point of the basilar trunk at each stage. Measurements obtained during each stage included: 1). the transverse carotid-oculomotor distance, that is, anteriorly between the oculomotor foramen and ICA, and posteriorly between the oculomotor nerve and ICA; and 2). the exposed length of the basilar artery, as seen under the microscope and on angiograms. RESULTS: Measurements were obtained before and after the addition of anterior clinoidectomy, mobilization of the ICA, and posterior clinoidectomy. Increases in expansion of the window and exposure of the upper basilar artery were documented as percentages of the control values. The anterior carotid-oculomotor distance averaged 7.1 mm (range, 5-10 mm) and 10.1 mm (range, 7-15 mm) before and after the additional surgical steps to expand the window, respectively. The posterior carotid-oculomotor distance averaged 12.7 mm (range, 9-18 mm) and 16.1 mm (range, 11-22 mm) before and after the additional surgical steps to expand the window, respectively. The exposed length of the basilar artery from the bifurcation to the clip was 4.2 mm (range, 1-13 mm) before expansion and 7 mm (range, 3-15 mm) after expansion. CONCLUSION: Anterior clinoidectomy and ICA mobilization increased the carotid-oculomotor space 44% anteriorly and 28% posteriorly. Posterior clinoidectomy increased the exposed length of the basilar artery by 69%. Superficial wide field exposure, expansion of the carotid-oculomotor window, and increased exposure of the upper basilar artery facilitate both visualization of the aneurysm for clip application and the use of proximal vascular control as an adjunct to basilar aneurysm surgery.  相似文献   
76.
The plasma concentration of the adipocyte-derived peptide adiponectin is decreased in patients with obesity and type 2 diabetes. The adiponectin gene is located on chromosome 3q27, where a diabetes susceptibility locus has been mapped. Adiponectin gene polymorphisms (single nucleotide polymorphisms [SNPs]) have been associated with BMI, insulin sensitivity, and type 2 diabetes in some cross-sectional studies. Our aim was to assess the contribution of these SNPs in the development of features of the insulin resistance syndrome in a 3-year prospective study in approximately 4,500 French Caucasian subjects from the Epidemiologic Data on the Insulin Resistance Syndrome (DESIR) cohort. For subjects who were normoglycemic at baseline, the 3-year risk of becoming hyperglycemic (diabetes or impaired fasting glucose) was affected by two SNPs: G-11391A and T45G. For G-11391A, the risk was increased in GA carriers (odds ratio [OR] adjusted for sex [versus GG] = 1.60 [95% CI 1.16-2.20]; P = 0.004). For T45G, it was increased in GG carriers (OR [versus TT] = 2.71 [1.31-5.60]; P = 0.007). After 3 years, GG subjects had a greater increase in BMI (P = 0.009) and waist-to-hip ratio (P = 0.007). Adiponectin levels at baseline were associated with the development of hyperglycemia (P = 0.005), but the predictive effects on the risk for hyperglycemia were independent of adiponectin genotypes. In conclusion, in the DESIR study, variations at the adiponectin locus affect body weight gain, body fat distribution, and onset of hyperglycemia, as well as adiponectin levels. Adiponectin gene SNPs may have several phenotypic effects that co-occur with the development of the metabolic syndrome.  相似文献   
77.
Uncertainty is a parameter associated with the result of a measurement; this parameter characterizes the dispersion of the values that could reasonably be attributed to the sample. Data processing methods do not take into account the influence of the imprecision and deviation of the experimental points of the calibration system and their impact on the final result of a sample analysis. The aim of this work is: (a) to propose, for each run, a simple method to calculate the uncertainty due to the calibration system (Uc); and (b) to present a method to determine the "intra-assay total uncertainty" (Ut) and evaluate its impact on the final result for an analyte. Ten replicates of standards, controls, and two serum-male and female samples were measured in the same run with a manual kit for determination of testosterone. To calculate Ut, random duplicate responses were selected. For controls and samples, Ut was affected by Uc (2.91% to 6.59%) and by the uncertainty of the measurement of the sample (Us) (1.01 to 8.73%); this allowed us to determine that Ut had values from 3.73% to 9.87%. While Us affects the result of a given sample, Uc affects the result of all the samples with a similar response (cpm). In the method proposed, Ut involves Us and Uc, both factors that introduce variations into the result of a sample by random causes. Intraassay total uncertainty includes the most probable result for the analytical methodology selected.  相似文献   
78.
Spectrophotometric and high-performance liquid chromatographic (HPLC) methods are developed for simultaneous determination of three binary mixtures with overlapping spectra. The spectrophotometric method is based on the use of second derivative of the ratio spectra (2DD) for resolution of three binary mixtures of indapamide with captopril (mixture 1), cinnarizine with heptaminol acefylline (mixture 2) and amoxycillin trihydrate with flucloxacillin sodium (mixture 3). The HPLC method depends on the separation of components of binary mixtures using ODS column with mobile phase consisting of acetonitrile and 5 mM aqueous heptane sulphonic acid sodium salt in ratios of (60:40, v/v, pH 5.5) for mixture 1, (50:50, v/v, pH 3.0) for mixture 2 and (35:65, v/v, pH 4.2) for mixture 3. The proposed methods are accurate, non-destructive and successfully applied for the determination of the three binary combinations in synthetic mixtures and commercial pharmaceutical products.  相似文献   
79.
Several methods are developed for the determination of two binary mixtures containing cyclizine hydrochloride with pyridoxine HCl (mixture (mix.) 1); and cinnarizine with piracetam (mix. 2). The resolution of the two binary mixtures has been accomplished by using numerical spectrophotometric methods as partial least squares (PLS-1) and principal component regression applied to UV spectra of the mixture and graphical spectrophotometric method as second derivative of the ratio spectra (2DD). In addition, HPLC methods were developed depending on using RP18 column with mobile phase consisting of acetonitrile/0.05 M KH2PO4 (50:50, v/v, pH 4.0) with UV detection at 239 nm for mix. 1, and mobile phase consisting of acetonitrile/0.05 M KH2PO4/triethylamine (50:50:0.2, v/v/v, pH 3.0) with UV detection at 227 nm for mix. 2. The proposed methods were successfully applied for the determination of the two binary combinations in synthetic mixtures and commercial tablets.  相似文献   
80.
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