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91.
OBJECTIVES: We investigated the relationship between Helicobacter pylori infection and abnormal periodontal conditions. METHODS: Data from the first phase of the third National Health and Nutrition Examination Survey were used. A total of 4504 participants aged 20 to 59 years who completed a periodontal examination and tested positive for H. pylori antibodies were examined. RESULTS: Periodontal pockets with a depth of 5 mm or more were associated with increased odds of H. pylori seropositivity (odds ratio [OR] = 1.47; 95% confidence interval [CI] = 1.12, 1.94) after adjustment for sociodemographic factors. This association is comparable to the independent effects of poverty on H. pylori (OR = 1.54; 95% CI = 1.10, 2.16). CONCLUSIONS: Poor periodontal health, characterized by advanced periodontal pockets, may be associated with H. pylori infection in adults, independent of poverty status.  相似文献   
92.
93.
A theory of cognitive control,aging cognition,and neuromodulation   总被引:12,自引:0,他引:12  
A theory is described which links cognitive changes observed in normal aging to an underlying decline in the function of the dopamine (DA) system projection to prefrontal cortex (PFC). The theory postulates that this neural mechanism is integral to the representation, maintenance and updating of context information, and as such impacts cognitive control across a wide range of cognitive domains, including working memory, attention, and inhibition. Behavioral and brain imaging data in support of the theory are discussed, which demonstrate selective impairments in context processing among healthy older adults associated with abnormal PFC activation. These findings highlight the utility of a computational approach to cognitive aging. Current directions for further refinement and validation of the model are outlined.  相似文献   
94.
PURPOSE OF REVIEW: An increase in refractory invasive fungal infections in the setting of marrow/solid organ transplantation and other immune-compromising clinical entities has provided the impetus for the development of new, more efficacious/less toxic antifungal agents. This review (1) examines currently available laboratory methods for the in-vitro evaluation of these new agents against both yeasts and filamentous fungi; (2) provides a summary of the most attractive investigational agents currently undergoing clinical trials/development; and (3) outlines the major refractory mycoses in contemporary medicine. RECENT FINDINGS: Fluconazole-resistant Candida spp., Trichosporon spp., zygomycetous genera, the endemic mycoses, Scedosporium, Aspergillus, and Fusarium spp., and an ever-expanding list of lesser-known hyaline and phaeoid genera inciting invasive fungal infections comprise the bulk of refractory mycoses in the immune-compromised host. In-vitro data generated from reference-based antifungal susceptibility testing methods indicate an increased armamentarium of potentially efficacious agents against most of these mycoses. SUMMARY: The newly approved antifungal agents caspofungin and voriconazole, used either as monotherapy or in combination regimens, have a significantly improved spectrum of activity over previously available therapeutic options. Correlation of clinical outcomes with investigational agents demonstrating in-vivo/in-vitro activity will provide critical information needed for the development of clinically significant minimum inhibitory concentration interpretative breakpoints.  相似文献   
95.
PURPOSE: Exercise increases the use of amino acids for glucose production and stimulates the oxidation of amino acids and other substrates to provide ATP for muscular contraction, and thus the availability of amino acids and energy for postexercise muscle protein synthesis may be limiting. The purpose of this study was to determine the potential of postexercise nutrient intake to enhance the recovery of whole-body and skeletal muscle protein homeostasis in humans. METHODS: Primed-continuous infusions of L-[1-13C]leucine and L-[ring-2H5]phenylalanine were initiated in the antecubital vein and blood was sampled from a femoral vein and a heated (arterialized) hand vein. Each study consisted of a 30-min basal, a 60-min exercise (bicycle at 60% VO2max), and a 180-min recovery period. Five men and five women were studied three times with an oral supplement administered immediately following exercise in random order: NO = 0, 0, 0; SUPP = 0, 8, 3; or SUPP+PRO = 10, 8, 3 g of protein, carbohydrate, and lipid, respectively. RESULTS: Compared to NO, SUPP did not alter leg or whole-body protein homeostasis during the recovery period. In contrast, SUPP+PRO increased plasma essential amino acids 33%, leg fractional extraction of phenylalanine 4-fold, leg uptake of glucose 3.5-fold, and leg and whole-body protein synthesis 6-fold and 15%, respectively. Whereas postexercise intake of either NO or SUPP resulted in a net leg release of essential amino acids and net loss of whole-body and leg protein, SUPP+PRO resulted in a net leg uptake of essential amino acids and net whole-body and leg protein gain. CONCLUSIONS: These findings suggest that the availability of amino acids is more important than the availability of energy for postexercise repair and synthesis of muscle proteins.  相似文献   
96.
Violence, a leading cause of injuries and death, is recognized as a major public health problem. In 1996, injuries were the second leading cause of hospitalizations in Jamaica. The estimated annual cost of in-patient care for injuries was 11.6 million US dollars. To develop strategies to reduce the impact of violence-related injuries on Jamaican health care resources, the Ministry of Health, Division of Health Promotion and Protection (MOH/DHPP) in collaboration with the Centers for Disease Control and Prevention and the Tropical Metabolic Research Institute, University of the West Indies Mona, designed and implemented a violence-related injury surveillance system (VRISS) at Kingston Public Hospital (KPH). In 1998, the VRISS, based on the International Classification of External Cause of Injury (ICECI), was implemented in the accident and emergency (A&E) department of Jamaica's tertiary care hospital, KPH. VRISS collects demographic, method and circumstance of injury, victim-perpetrator relationship and patient's discharge status data. From 8/1/98 to 7/31/99, data on 6,107 injuries were collected. Injuries occurred primarily among males aged 25-44 years. Most injuries (54%; 3171) were caused by use of a sharp object. Nearly half (49%; 2992) were perpetrated by acquaintances. The majority, 70% (4,252), were the result of a fight or argument and 17% were admitted to the hospital. The VRISS utilized A&E department data to characterize violence-related injuries in Jamaica, a resource-limited environment. These data will be used to guide intervention development to reduce violence-related injuries in Jamaica.  相似文献   
97.
Meaning in life is a multi-faceted construct that has been conceptualized in diverse ways. It refers broadly to the value and purpose of life, important life goals, and for some, spirituality. We developed a measure of meaning in life derived from this conceptualization and designed to be a synthesis of relevant theoretical and empirical traditions. Two samples, all cancer patients, provided data for scale development and psychometric study. From exploratory and confirmatory factor analyses the Meaning in Life Scale (MiLS) emerged, and includes four aspects: Harmony and Peace, Life Perspective, Purpose and Goals, Confusion and Lessened Meaning, and Benefits of Spirituality. Supporting data for reliability (internal consistency, test–retest) and construct validity (convergent, discriminant, individual differences) are provided. The MiLS offers a theoretically based and psychometrically sound assessment of meaning in life suitable for use with cancer patients.  相似文献   
98.
INTRODUCTION: Muscle spasticity may adversely affect pulmonary function after spinal cord injury (SCI). However, there is limited information regarding the treatment of spasticity as a determinant of pulmonary function. This study presents the case of a man with C4 tetraplegia who had severe spasticity and difficulty weaning from ventilatory support. METHODS: Case presentation. RESULTS: Severe spasticity likely contributed to respiratory compromise in this patient. Successful and rapid weaning from the ventilator occurred within 3 weeks of baclofen pump placement. CONCLUSIONS: Randomized clinical trials among SCI patients with significant spasticity are needed to determine whether intervention with a baclofen pump facilitates earlier ventilatory weaning.  相似文献   
99.
To determine the prevalence of hepatitis A virus (HAV) infection in the general U.S. population, sera from participants in the Third National Health and Nutrition Examination Survey (NHANES III) conducted in 1988–1994 were tested for antibody to HAV (anti-HAV). Among 21,260 participants aged ≥6 years tested, the overall prevalence of infection was 31.3%, and increased markedly with age. The age-adjusted prevalence was significantly higher among foreign- compared to U.S.-born participants, and was highest among Mexican-Americans and lowest among non-Hispanic whites. Among U.S.-born children, only Mexican-American ethnicity and income below the poverty level were associated with HAV infection in a multivariate model. During this period before hepatitis A vaccination, age, ethnicity and birthplace were the most important determinants of HAV infection in the United States.  相似文献   
100.
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