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161.
BACKGROUND: Plasma viral load has recently been associated with clinical outcome in patients with human immunodeficiency virus (HIV) infection and acquired immunodeficiency syndrome (AIDS). We hypothetized that, in addition to CD4 lymphocytes, plasma HIV-1 RNA counts are predictive of postoperative outcome. METHODS: HIV-infected and AIDS patients admitted to a major teaching hospital requiring invasive or surgical procedures were retrospectively analyzed for postoperative outcome. Preoperative and postoperative immune cell counts including plasma HIV-1 RNA counts were recorded. Chi-square analysis, Fisher's exact test, and multivariate regression were performed with statistical significance P 相似文献   
162.
Law, which is a fundamental element of effective public health policy and practice, played a crucial role in many of public health's greatest achievements of the 20th century. Still, conceptual legal frameworks for the systematic application of law to chronic disease prevention and control have not been fully recognized and used to address public health needs. Development and implementation of legal frameworks could broaden the range of effective public health strategies and provide valuable tools for the public health workforce, especially for state and local health department program managers and state and national policy makers. In an effort to expand the range of effective public health interventions, the Centers for Disease Control and Prevention will work with its partners to explore the development of systematic legal frameworks as a tool for preventing chronic diseases and addressing the growing epidemic of obesity, heart disease, stroke, and other chronic diseases and their risk factors.  相似文献   
163.
OBJECTIVE: Recent studies of ovarian cancer have suggested a role for inflammation in carcinogenesis. Data from a population-based case-control study in Hawaii were examined to assess the relation between polymorphisms in cytokines involved with the inflammatory response, specifically members of the interleukin (IL) family and the incidence of ovarian cancer. PATIENTS AND METHODS: The analysis of 182 epithelial ovarian cancer cases and 219 controls focused on the polymorphisms in the following genes: IL-1alpha, IL-1beta, IL-6, IL-10, and IL-18. Genotype data were obtained from blood samples collected in participants' homes, and reproductive, demographic, and lifestyle histories were collected during interview. RESULTS: There were no significant odds ratios (ORs) for ovarian cancer by allelic variants in any of the IL genes after adjusting for age, ethnicity, education, oral contraceptive pill use, pregnancy, and history of tubal ligation. Although there was a significantly reduced risk of ovarian cancer risk among women with an IL-1alpha (-4845) T allele compared to women with two G alleles (OR: 0.59; 95% confidence interval: 0.37-0.97) after adjustment for age and ethnicity, the trend was not significant (p = 0.10). Further examination of the data suggested that women with at least one IL-18 variant allele (a G to C transition at position -137) were at significantly decreased risk of advanced ovarian cancer (OR: 0.51; 95% confidence interval: 0.28-0.90) compared to women with the IL-18 GG genotype. There was a significant difference in the risk of ovarian cancer associated with the IL-18 C allele by stage at diagnosis (p = 0.04 for homogeneity in the ORs): cases with IL-18 GC or CC genotypes were less likely to be diagnosed at regional/distant stages. Analysis of the data within ethnic subgroups revealed a significant positive association of the heterozygous IL-18 GC genotype with ovarian cancer risk among Native Hawaiian women (OR: 9.96; 95% CI: 1.88-52.90). The OR for ovarian cancer was not significant for Native Hawaiian women homozygous for the IL-18 C allele, but only one case and control had the IL-18 CC genotype. CONCLUSIONS: Overall, this study does not support an association of selected IL-1alpha, IL-1beta, IL-6, IL-10, or IL-18 polymorphisms with the risk for ovarian cancer. However, the IL-18 G137C variant may be a marker for ovarian cancer progression or metastasis.  相似文献   
164.
A group of neurons with the characteristics of dentate gyrus granule cells was found at the hilar/CA3 border several weeks after pilocarpine- or kainic acid-induced status epilepticus. Intracellular recordings from pilocarpine-treated rats showed that these "granule-like" neurons were similar to normal granule cells (i. e., those in the granule cell layer) in membrane properties, firing behavior, morphology, and their mossy fiber axon. However, in contrast to normal granule cells, they were synchronized with spontaneous, rhythmic bursts of area CA3 pyramidal cells that survived status epilepticus. Saline-treated controls lacked the population of granule-like cells at the hilar/CA3 border and CA3 bursts. In rats that were injected after status epilepticus with bromodeoxyuridine (BrdU) to label newly born cells, and also labeled for calbindin D(28K) (because it normally stains granule cells), many double-labeled neurons were located at the hilar/CA3 border. Many BrdU-labeled cells at the hilar/CA3 border also were double-labeled with a neuronal marker (NeuN). Taken together with the recent evidence that granule cells that are born after seizures can migrate into the hilus, the results suggest that some newly born granule cells migrate as far as the CA3 cell layer, where they become integrated abnormally into the CA3 network, yet they retain granule cell intrinsic properties. The results provide insight into the physiological properties of newly born granule cells in the adult brain and suggest that relatively rigid developmental programs set the membrane properties of newly born cells, but substantial plasticity is present to influence their place in pre-existing circuitry.  相似文献   
165.
OBJECTIVE: To review the natriuretic hormone system and discuss its diagnostic, prognostic, and therapeutic potential in critically ill children. DATA SOURCE: A thorough literature search of MEDLINE was performed using search terms including heart defects, congenital; cardiopulmonary bypass, atrial natriuretic factor; natriuretic peptide, brain; carperitide; nesiritide. Preclinical and clinical investigations and review articles were identified that describe the current understanding of the natriuretic hormone system and its role in the regulation of vascular tone and fluid balance in healthy adults and children and in those with underlying cardiac, pulmonary, and renal disease. RESULTS: A predictable activation of the natriuretic hormone system occurs in children with congenital heart disease and congestive heart failure. Further study is needed to confirm preliminary reports that measurement of natriuretic hormone levels in critically ill children provides diagnostic and prognostic information, as has been demonstrated in adult cardiac populations. Natriuretic hormone infusions provide favorable hemodynamic changes and symptomatic relief when used in adults with decompensated congestive heart failure, and uncontrolled case series suggest that similar benefits may exist in children. The biological activity of the natriuretic hormone system may be decreased following pediatric cardiopulmonary bypass, and additional studies are needed to determine whether natriuretic hormone infusions provide clinical benefit in the postoperative period. Preliminary reports suggest that natriuretic hormone infusions cause physiologic improvements in adults with acute lung injury and asthma but not in those with acute renal failure. CONCLUSIONS: Although important perturbations of the natriuretic hormone system occur in critically ill infants and children, further investigation is needed before the measurement of natriuretic peptides and the use of natriuretic hormone infusions are incorporated into routine practice.  相似文献   
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167.
Activation of the medial olivocochlear reflex (MOCR) can be assessed indirectly using transient-evoked otoacoustic emissions (TEOAEs). The change in TEOAE amplitudes when the MOCR is activated (medial olivocochlear (MOC) shift) has most often been quantified as the mean value in groups of subjects. The usefulness of MOC shift measurements may be increased by the ability to quantify significant shifts in individuals. This study used statistical resampling to quantify significant MOC shifts in 16 subjects. TEOAEs were obtained using transient stimuli containing energy from 1 to 10 kHz. A nonlinear paradigm was used to extract TEOAEs. Transient stimuli were presented at 30 dB sensation level (SL) with suppressor stimuli presented 12 dB higher. Contralateral white noise, used to activate the MOCR, was presented at 30 dB SL and was interleaved on and off in 30-s intervals during a 7-min recording period. Confounding factors of middle ear muscle reflex and slow amplitude drifts were accounted for. TEOAEs were analyzed in 11 1/3-octave frequency bands. The statistical significance of each individual MOC shift was determined using a bootstrap procedure. The minimum detectable MOC shifts ranged from 0.10 to 3.25 dB and were highly dependent on signal-to-noise ratio at each frequency. Subjects exhibited a wide range of magnitudes of significant MOC shifts in the 1.0–3.2-kHz region (median?=?1.94 dB, range?=?0.34–6.51 dB). There was considerable overlap between the magnitudes of significant and nonsignificant shifts. While most subjects had significant MOC shifts in one or more frequency bands below 4 kHz, few had significant shifts in all of these bands. Above 4 kHz, few significant shifts were seen, but this may have been due to lower signal-to-noise ratios. The specific frequency bands containing significant shifts were variable across individuals. Further work is needed to determine the clinical usefulness of examining MOC shifts in individuals.  相似文献   
168.
169.
170.
ObjectiveTo examine comprehension of nutrition labels across sociodemographic groups using a measure of health literacy.MethodsCross-sectional survey of a community sample of adults including an adapted version of the Newest Vital Sign for Canadian Nutrition Facts table on prepackaged grocery products, including numerical conversion questions for calorie content and percent daily value.ResultsApproximately two thirds of participants were able to correctly identify calorie content and percent daily value from the nutrition label. Participants with higher education and higher income, those aged ≤ 64 years, and those who look at nutritional facts or calories were significantly more likely to estimate the correct calorie content. Participants were significantly more likely to correctly identify percent daily value if they reported higher education, higher income, and white ethnicity.Conclusions and ImplicationsApproximately one third of participants could not comprehend basic information on Canadian nutrition labels. Lower socioeconomic status was associated with poorer performance.  相似文献   
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