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21.
Published reports of the effectiveness of preterm birth prevention programs have produced mixed results. Many larger observational studies suggest benefit. The randomized trials, however, suggest no effect on reducing rates of preterm birth in high-risk populations. This article reviews and critiques these reports and suggests areas for further research.  相似文献   
22.
Effects of niacin (nicotinic acid or nicotinamide) supplementation of dairy cow diets on apparent total tract nutrient digestibility, milk yield and milk composition were determined using six mid-lactation Holstein cows in a replicated 3 x 3 Latin square design arranged to test for residual treatment effects. Treatments were control, 12 g/d of nicotinic acid or 12 g/d of nicotinamide. Periods were 14 d long; d 1 to 4 served as an adaptation period before treatment administration commenced (d 5 to 14). Effects of supplemental niacin on plasma nonesterified fatty acid (NEFA) concentrations and plasma glucose concentrations were tested following saline injection on d 10. Blood was then sampled for 5.5 h at 15-min intervals. On d 13, cows were treated similarly except that epinephrine replaced saline. The area below d-10 curves was subtracted from the area below d-13 curves to serve as an indicator of niacin's effect on plasma NEFA and glucose concentration responses to epinephrine injection. Niacin treatments did not change the area differences for plasma glucose compared to the control treatment; however, there was a trend for niacin to reduce the area difference compared to the control treatment for plasma NEFA. Niacin treatments did not alter dry matter intake, nutrient digestibility, milk yield or composition. Niacin supplementation increased the number of entodinia protozoa in rumen fluid.  相似文献   
23.
BACKGROUND: Assessment of inpatient asthma management has generally been limited to urban settings, including Chicago, which is known for its high asthma morbidity and mortality. Previously published data have been based on survey methodology. The Suburban Asthma Consortium (SAC) sought to obtain patient-based data unique to the Chicago suburbs to improve asthma care in those areas. OBJECTIVE: To evaluate current inpatient asthma management based on the 1997 National Asthma Education and Prevention Program (NAEPP). DESIGN: Retrospective chart review of all hospitalized patients 3-65 years bearing asthma-related ICD-9 codes for fiscal year 2002 in community, nonteaching hospitals in Chicago suburbs. RESULTS: Nine hundred two cases were submitted from seven hospitals. The majority ( > or = 75%) received inhaled bronchodilators, systemic steroids, oxygen and pulse oximetry. Antibiotic use (67%), chest radiography (85%), complete blood count (77%), and electrolytes (59%) appeared excessive in view of NAEPP recommendations. Peak flow monitoring (PFM) was recorded on admission in 45% of patients 5 years old and older; 52% had PFM during hospitalization. Thirty-eight percent of patients were taking ICS prior to admission; of those not on ICS, only 12% were newly diagnosed asthmatics. Overall, 51% of patients were discharged with ICS. Patients were more likely to receive ICS at discharge if they had required intensive care (ICU), had been on ICS prior to admission, were referred to an asthma specialist while hospitalized, or were insured. Patients with Medicare/Medicaid (MC/MA) had more repeat emergency visits and hospitalizations, longer lengths of stay, and received less ICS at discharge. Depending on the parameter, 41% or less patients received discharge planning education and were not more likely to have received education if in the ICU. Results ranged significantly between hospitals for most parameters (p < 0.05 or less). CONCLUSION: Study subjects received appropriate acute therapy and oxygen monitoring, but there was a divergence from NAEPP recommendations regarding PFM, ICS use, antibiotics, and laboratory evaluation. Patients receiving MC/MA experienced higher morbidity and received less ICS. Discharge asthma education was suboptimal for most hospitals. Most parameters demonstrated significantly wide practice variations between hospitals. Peak flow monitoring and patient education findings differed significantly from those in survey-conducted studies.  相似文献   
24.
Body pain and treatment response in late-life depression.   总被引:2,自引:0,他引:2  
OBJECTIVE: The authors investigated the influence of body pain on 1) time to treatment response and 2) suicidal ideation, in late-life depression. They hypothesized that higher levels of body pain would predict a longer time to and lower likelihood of response, and increased levels of suicidal ideation. METHODS: Subjects (N=187) were older adult outpatients (age > or =69 years), with current episodes of major depression, who were openly treated with paroxetine up to 40 mg daily and weekly interpersonal psychotherapy. Response was defined as 3 consecutive weeks of Hamilton Rating Scale for Depression at < or =10. Body pain was measured with the Bodily Pain Index of the SF-36 quality-of-life assessment. Authors used survival-analysis models on the responder sample to test the effect of body pain on response, after controlling for severity of depression. RESULTS: Overall response rate was 75.4%. Nonresponders reported more severe pain at baseline. After covarying for severity of baseline depression, no effect was found for physical pain on time-to-response or degree of suicidality. Bodily pain remained stable during acute treatment for responders, independent of depression response to combination psychotherapy and antidepressant treatment. CONCLUSIONS: Older adult patients with higher levels of physical pain can still respond to antidepressant treatment; however, reported bodily pain may be associated with a more difficult-to-treat depression.  相似文献   
25.
BACKGROUND: A subgroup of children with obsessive-compulsive and tic disorders are proposed to have an infectious trigger. The purpose of this study was to investigate the relationship between group A streptococcal titers and symptom fluctuations in children with a clinical course resembling that described for pediatric autoimmune neuropsychiatric disorders associated with streptococcus. METHODS: Twenty-five children with obsessive-compulsive disorder and/or tic disorder were evaluated for neuropsychiatric severity and group A streptococcal antibody titers (streptolysin O, deoxyribonuclease B, and carbohydrate A) at 6-week intervals for > or = six consecutive evaluations (total visits=277). RESULTS: Children with large symptom fluctuations (n=15) were compared with children without dramatic fluctuations (n=10). Co-movements of obsessive-compulsive/tic severity and group A streptococcal antibodies were assessed. In subjects with large symptom changes, positive correlations were found between streptococcal titers and obsessive-compulsive severity rating changes (p=.0130). These subjects were also more likely to have elevated group A streptococcal titers during the majority of observations (p=.001). Tic symptom exacerbations occurred more often in the fall/winter months than spring/summer months (p=.03). CONCLUSIONS: Patients with marked obsessive-compulsive/tic symptom changes may be characterized by streptococcal titer elevations and exhibit evidence of seasonal tic exacerbations.  相似文献   
26.
Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.  相似文献   
27.
28.
Thyrotropin releasing hormone (TRH) was administered intravenously to ten patients with Alzheimer's Disease (AD) in a high-dose paradigm, thought to maximize central nervous system effects and potentially produce facilitation of cholinergic function, a known property of the neuropeptide. Acute effects of TRH on behavioral, cognitive and physiologic measures were assessed after patients received 0.1 mg/kg TRH, 0.3 mg/kg TRH and placebo, the higher TRH dose and placebo being given in a randomized, double-blind fashion. Patients showed statistically significant increases in arousal and improvement in affect, as well as a modest improvement in semantic memory, all after receiving the higher TRH dose. Both TRH doses produced transient rises in systolic blood pressure, with no effect on diastolic blood pressure, heart rate or temperature. This study suggests that high-dose TRH can be safely administered to AD patients and is neurobehaviorally active; further studies are needed to determine the extent and mechanism of the cognitive and psychobiological properties of this peptide in AD and other neuropsychiatric disorders.  相似文献   
29.
Thromboxane, a prostanoid derivative, is a central mediator of the progressive dermal ischemia seen in the distal dying flap. Prostacyclin; a vasoactive prostanoid derivative, has been found to enhance ischemic flap survival. This study examines the effects of prostacyclin and UK 38485 (specific thromboxane synthetase inhibitor), separately and combined, in axial flap survival in the pig. Each increased flap survival over control flaps; their combined use demonstrated an even greater flap survival (p less than 0.005).  相似文献   
30.
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