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Human immunodeficiency virus (HIV) quasi-species fluctuate both in time and in space. In general intrapatient variation is less extensive than interpatient variation. The V1 and V2 hypervariable regions of the envelope gene were analyzed for patient samples harboring highly divergent genomes in other loci. Proviral sequences were amplified by PCR, cloned, and sequenced. It was concluded that intrapatient variation may exceed interpatient variation but the presence of two clearly distinct populations was not confirmed. The env hypervariable regions appeared to be evolving independently of one another, cautioning against extrapolation of data, particularly from the V3 region. Virus typing and the assessment of HIV superinfection by genetic methods will prove difficult and experimental approaches will have to be carefully designed.  相似文献   
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Heart failure with normal ejection fraction (HFNEF) is currently the most prevalent clinical phenotype of heart failure. However, the treatments available have shown no reduction in mortality so far. Advances in the omics sciences and techniques of high data processing used in molecular biology have enabled the development of an integrating approach to HFNEF based on systems biology.This study aimed at presenting a systems-biology-based HFNEF model using the bottom-up and top-down approaches.A literature search was conducted for studies published between 1991 and 2013 regarding HFNEF pathophysiology, its biomarkers and systems biology. A conceptual model was developed using bottom-up and top-down approaches of systems biology.The use of systems-biology approaches for HFNEF, a complex clinical syndrome, can be useful to better understand its pathophysiology and to discover new therapeutic targets.  相似文献   
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Background: We evaluated the impact of surgically-induced weight loss on Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS), electrocardiographic changes, pulmonary arterial pressure and daytime sleepiness in morbidly obese patients. Methods: 16 women and 13 men (n=29) underwent bariatric surgery in a 3-year period. The following tests were performed before and 1 year after surgery: nocturnal polysomnography, daytime Multiple Sleep Latency Test (MSLT), and echocardiogram. Results: Mean age was 37.9±11 years (range 20-56). Preoperative body mass index was 56.5±12.3 kg/m2 and it was 39.2±8.5 kg/m2 at 13.7±6.6 months follow-up. Performed surgical procedures included: vertical banded gastroplasty in 6, Roux-en-Y gastric bypass in 12, and Distal Roux-en-Y gastric bypass in 11. Weight loss induced by surgery eliminated OSAHS in 46% of obese patients with an important improvement in oxygen saturation. Neck, thorax, waist and hip circumferences decreased significantly after surgical intervention but only neck circumference correlated significantly with the apnea/hypopnea index (Spearman rho=0.63, P <0.0001). Electrocardiographic abnormalities were present in 9 patients (31%) before surgery (sinus arrhythmia, ventricular arrhythmias, and sinus arrest). The number of electrocardiographic abnormalities decreased after surgery but new abnormalities appeared in some patients. Systolic pulmonary arterial pressure significantly decreased in the group of patients in whom OSAHS disappeared after surgery. Daytime sleepiness persisted after surgery in most patients. Conclusion: Bariatric surgery effectively reduces respiratory disturbances during sleep and improves pulmonary hypertension. Electro cardiographic abnormalities change after surgery. Daytime sleepiness appeared not to be related to respiratory disturbances during sleep.  相似文献   
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We compared the efficacy of rofecoxib and ketorolac in controlling postoperative pain after outpatient surgery. Patients were randomly assigned to receive either rofecoxib or ketorolac preoperatively and every morning for 5 postoperative days. Patients in both groups received oxycodone as needed for breakthrough pain. After 5 postoperative days, patients were asked for information-pain score; number of supplemental analgesics used; and severity of any incision-site bleeding, nausea, or diarrhea. Rofecoxib and ketorolac did not differ on these measures. Rofecoxib and ketorolac are equally effective in controlling postoperative pain.  相似文献   
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The aim of this study was to develop a three-dimensional finite element model of the mandible, including its TMJ. The model consisted of 7942 nodes and 41,010 elements, which were obtained from a convergence test, done to minimize the result error. It included cancellous and cortical bone, periodontal ligament, masticatory muscles (masseters, temporalis, lateral and internal pterygoids), teeth and the articular disk. All characteristics such as dental, mandibular, and muscle geometry were obtained from a computerized tomography (CT) of a living person. CT sections were scanned and digitized with a CAD software program. After images were adequately assembled, a vertical tracing was done which allowed the definition of a three-dimensional mesh. Modeling of teeth was carried out independently and the periodontal ligament was later included, limiting the alveolar area. Muscles were modeled based on flat-scale photographs and total muscle force was distributed in multiple vectors. The articular disk was generated having 2 mm of thickness with the combination of spring-type (axial stiffness) and gap-type (contact) elements. The model was then analyzed with finite element method (FEM) software where a mesh was generated and values for Poisson's ratio, elasticity, and shear modulus were assigned. These were orthotropic for cancellous and cortical bone, and isotropic for dentin, periodontal ligament, articular disk, and temporal bone. The boundary conditions were defined restricting the nodes on the periphery of the temporal bone. It was therefore possible to generate a three-dimensional finite element model based on information obtained in vivo.  相似文献   
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The content of catecholamines in the Fallopian tube and the uterus and the plasma levels of estradiol and progesterone were studied in cycling women. During the follicular phase norepinephrine levels were 33.4+/-7.1, 50.5+/-8.0, and 145.7+/-43.6 ng. per gram of wet tissue in the external, middle, and internal segments of the Fallopian tube, respectively. During the luteal phase norepinephrine content increased significantly in the external and middle portions (219.3+/-57.0 and 206.2+/-34.3 ng. per gram) whereas it remained unchanged in the internal one (185.2+/-53.6 ng. per gram). The NE content of the external and middle segments correlated significantly with plasma progesterone levels (r = 0.76 and 0.82, respectively, whereas oviductal epincphrine levels did not show significant changes as a function of the stage of the menstrual cycle. Uterine epinephrine content decreased by 67 per cent during the luteal phase whereas norepinephrine remained unchanged.  相似文献   
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Objective  To describe the spatial distribution of lymphatic filariasis and its relationship with the socioenvironmental risk indicator, thus identifying priority localities for interventions in endemic urban areas.
Methods  The study area was the municipality of Jaboatão dos Guararapes, State of Pernambuco, Brazil. The data sources were a parasitological survey and the 2000 demographic census. From these data, a socioenvironmental composite risk indicator was constructed using the 484 census tracts (CT) as the analysis units, based on the score-formation technique. Census tracts with higher indicator values presented higher risk of occurrences of filariasis.
Results  Six thousand five hundred and seven households were surveyed and 23 673 individuals were examined, among whom 323 cases of microfilaremia were identified. The mean prevalence rate for the municipality was 1.4%. The indicator showed that 73% (237/323) of the cases of microfilaremia were in high-risk areas (third and fourth quartiles) with worse socioenvironmental conditions (RR = 4.86, CI = 3.09–7.73, P  <   0.05).
Conclusions  The socioenvironmental composite risk indicator demonstrated sensitivity, since it was able to identify the localities with greater occurrence of infection. Because it can stratify spaces by using official and available data, it constitutes an important tool for use in the worldwide program for eliminating lymphatic filariasis.  相似文献   
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For anatomic and technical reasons, it is often difficult to achieve guiding-catheter stability in the segmental arteries during embolization of spinal vascular lesions. We have developed a segmental artery exchange technique using a thin-walled 4F nontapered catheter that is safe and achieves a stable guiding-catheter position. This catheter accommodates both the flow-guided and variable-stiffness microcatheters, allowing selective catheterization and treatment of spinal vascular lesions.  相似文献   
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