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The etiology of obesity is multifactorial and still unclear. Genetic factors play a significant role and include several gene candidates: polymorphisms of genes for ss(2)-adrenoreceptor, resistin, estrogen receptor-a and peroxisome proliferator-activated receptor-gamma. Moreover, peptides regulating hunger and satiety, e.g. leptin, galanin, cholecystokinin and neuropeptide Y, and altered nutritional patterns have been implicated. Also, factors associated with aging, e.g. decreased levels of growth hormone and dehydroepiandrosterone, and the activity of the sympathetic nervous system (resting metabolism and thermogenesis) cannot be disregarded. Participation of the sex steroids and inflammatory factors has also been postulated in the etiology of obesity. Three phenotypes of obesity are postulated; however, the visceral (abdominal) phenotype is typical of postmenopausal women and is characterized by several metabolic disorders with high risks of diabetes mellitus type 2 and cardiovascular disease. On the basis of personal experience and data from evidence-based medicine, diagnostic-therapeutic algorithms of climacteric obesity are presented.  相似文献   
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Organophosphate compounds are cholinesterase inhibitors widely used in agriculture, industry, household products, and even as chemical weapons. Their major mechanism of acute toxic action is the inhibition of acetylcholinesterase, which is responsible for the degradation of the neurotransmitter acetylcholine. An organophosphorus ester-induced chronic neurotoxicity (OPICN) syndrome has been proposed. The OPICN syndrome could result from both long-term exposure to subclinical doses of OPs and after acute poisoning. Development of animal models for the cognitive decline are required and could later help to elucidate the mechanisms involved in this long-term effect on the central nervous system. Previously, we have found performance decrements in a four-trial repeated acquisition spatial task in a water maze. The present study includes two experiments to extend the long-term behavioral effects observed. Rats were injected either once or twice with chlorpyrifos (CPF) and then tested months after in a two-trial repeated acquisition task in a water maze. Our results confirm and extend the long-term behavioral effects of subcutaneous administration of CPF. The two treatments used produced performance decrements that suggest functional central nervous system alterations.  相似文献   
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Background: Both pain and the pharmacologic management of pain can cause the undesirable effect of sleep disruption. One goal of basic and clinical neuroscience is to facilitate rational drug development by identifying the brain regions and neurochemical modulators of sleep and pain. Adenosine is thought to be an endogenous sleep promoting substance and adenosinergic compounds can contribute to pain management. In the pontine brain stem adenosine promotes sleep but the effects of pontine adenosine on pain have not been studied. This study tested the hypothesis that an adenosine agonist would cause antinociception when microinjected into pontine reticular formation regions that regulate sleep.

Methods: The tail flick latency (TFL) test quantified the time in seconds for an animal to move its tail away from a thermal stimulus created by a beam of light. TFL measures were used to evaluate the antinociceptive effects of the adenosine A1 receptor agonist N6-p-sulfophenyladenosine (SPA). Pontine microinjection of SPA (0.1 [mu]g/0.25 [mu]l, 0.88 mm) was followed by TFL measures as a function of time after drug delivery and across the sleep-wake cycle.

Results: Compared with saline (control), pontine administration of the adenosine agonist significantly increased latency to tail withdrawal (P < 0.0001). The increase in antinociceptive behavior evoked by the adenosine agonist SPA was blocked by pretreatment with the adenosine A1 receptor antagonist 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX, 0.75 ng/0.25 [mu]l, 10 [mu]m).  相似文献   

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While commercial surrogate parenting arrangements continue to flourish in the U.S., Britain has made it a criminal offense for third parties to benefit from surrogacy. Voluntary surrogacy, however is still within the law. Banning commercial surrogacy while leaving voluntary surrogacy lawful seems neither logical nor fair. A more equitable solution would be to license stringently and control both commercial and nonprofit agencies to provide these services.  相似文献   
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While balloon valvuloplasty has been widely used for the treatment of congenital valvular pulmonary stenosis (PS) in children and adults, its use in elderly patients is less common. An 80-year-old woman with congenital valvular PS received valvuloplasty with double-balloon technique. Right ventricle systolic pressure and pulmonary valve systolic pressure gradient decreased from 95 to 44 mm Hg and from 75 to 35 mm Hg, respectively. Follow-up Doppler echocardiography 2 months later showed further decrease in the transvalvular systolic pressure gradient to 29 mm Hg. The patient had symptomatic relief, and no major complication was noted. Balloon pulmonary valvuloplasty can be an effective treatment for elderly patients with congenital valvular PS.  相似文献   
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OBJECTIVE: To assess the impact of activity restriction (AR) on the incidence of preterm birth in women treated for preterm labor testing negative for fetal fibronectin (fFN). STUDY DESIGN: Women who were diagnosed with preterm labor and tocolyzed with magnesium sulfate were concurrently screened with fFN for the purpose of subsequent management. Included were consenting patients with negative fFN, gestational age 23 0/7-33 6/7 weeks, cervical dilation < or =3 cm, and minimal vaginal bleeding. Patients were randomized to AR or no AR. Primary study outcome was incidence of preterm delivery and interval from randomization to delivery. RESULTS: A total of 73 women with negative fFN were randomized (36 with AR, 37 without AR). The overall preterm birth rate was 40%, with 44.4% of patients with AR and 35.1% of patients without AR delivering preterm, p=0.478. CONCLUSION: Maternal AR did not impact pregnancy outcome. The incidence of preterm birth in symptomatic women testing fFN negative was higher than previously reported.  相似文献   
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BACKGROUND AND PURPOSE: Taiwan's National Health Insurance (NHI) program has considered the use of capitation payments to health care providers as a method for control of the rising costs of the system. The establishment of capitation payments usually requires the performance of risk adjustment. The purposes of this study were to develop a diagnosis-based risk adjustment model for the NHI and to evaluate its predictability. METHODS: Using a 2% random sample of 371,620 NHI enrollees, the authors developed a Taiwan version of the Principal Inpatient Diagnosis Cost Groups (TPIPDCGs) from 1996 claim records to predict an individual's expenditure in 1997. Weighted least squares regression models were built in an estimation sample (two-thirds of the study sample), and were cross-validated in a validation sample (the remaining one-third of the study sample). Predictive R2 and predictive ratios were used to evaluate the model's predictability. RESULTS: Only 7.88% of the study sample could be classified into 1 of the 16 TPIPDCGs. Combined with demographic variables, which alone could explain 3.7% of the variation in an individual's future expenditure, the risk adjustment model based on TPIPDCGs could explain 12.2% of expenditure variation. In addition, the finding that the predictive ratios of the TPIPDCG model approximated unity better than those of the demographic model in all subgroups indicates that the capitation payment as predicted by the TPIPDCG model for each subgroup would better correlate to the actual spending. CONCLUSION: Taiwan's risk-adjusted capitation model based on principal inpatient diagnoses has higher predictability on individual's future expenditure than its counterpart in the USA. This finding provides insight into not only the development of Taiwan's diagnosis-based risk adjustment models but also the necessity of modification when applying foreign-developed risk adjustment models to the NHI.  相似文献   
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