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A total of 482 bats representing 32 species and two families were captured in the Amazon forests of the Amapá state in northern Brazil. Nineteen Artibeus planirostris bats (3.9 %) were infested with 160 ticks, all identified as Ornithodoros hasei. Three pools of larvae were screened for rickettsial DNA via polymerase chain reaction (PCR) targeting three rickettsial genes: gltA, ompA and htrA. Only one of them yielded an amplicons of the expected size for all three molecular assays. Comparisons of the obtained sequences including a phylogenetic analysis confirmed the occurrence of “Candidatus Rickettsia wissemanii” in Brazil.

  相似文献   
85.
A new benzodiazepine pharmacology.   总被引:12,自引:0,他引:12  
Classical benzodiazepine drugs are in wide clinical use as anxiolytics, hypnotics, anticonvulsants, and muscle relaxants. They act by enhancing the gamma-aminobutyric acid(A) (GABA(A)) receptor function in the central nervous system. The pharmacological relevance of the multitude of structurally diverse GABA(A) receptor subtypes has only recently been identified. Based on an in vivo point mutation strategy, alpha(1)-GABA(A) receptors were found to mediate sedation, anterograde amnesia, and part of the seizure protection, whereas alpha(2)-GABA(A) receptors, but not alpha(3)-receptors, mediate anxiolysis. Rational drug targeting to specific receptor subtypes has now become possible. Only restricted neuronal networks will be modulated by the new subtype-selective drugs. Promising new anxiolytics have already been developed. A new pharmacology of the benzodiazepine site is on the horizon.  相似文献   
86.

Purpose

Living in a cold home increases the risk of dying in winter, especially in older people. However, it is unclear which individual factors predict whether older people are living in cold homes.

Methods

Thousand four hundred two men aged 74–95 years from a U.K. population–based study reported difficulties in keeping warm during winter, answering four simple “yes/no” questions. Associations between individual's characteristics and each of the four self-reported measures of cold homes were estimated using logistic regression models. Next, we investigated whether measures of cold homes predict mortality over the subsequent 2.1 years.

Results

Manual social class, difficulties making ends meet, and not being married were each associated (P < .05) with each of the four measures of cold homes (adjusted odds ratios ranged from 1.61 to 4.68). Social isolation, poor respiratory health, and grip strength were also associated with reports of cold homes. Hundred twenty-six men died; those who reported the presence of at least three measures cold homes had increased mortality (adjusted hazard ratios 2.85 [95% confidence interval, 1.11–7.30, P = .029]).

Conclusions

Older people who find it hard to keep warm in winter, and have an elevated mortality, could be identified using a self-report questionnaire.  相似文献   
87.
We find ourselves in an era of unprecedented growth in the development and use of so-called “orphan” drugs to treat rare diseases, which are poised to represent more than one-fifth of pharmaceutical expenditures by 2022. This widespread use has been facilitated by legislative and regulatory incentives in both the United States and abroad, yet US payers and health systems have not yet made a concerted effort to understand whether and how rare diseases require special considerations on their part and how to adapt traditional methods of health technology assessment and economic evaluation to accommodate these situations. In this article, we explore the general ethical dilemmas that rare diseases present, steps taken by health technology assessment bodies worldwide to define the level of rarity that would necessitate special measures and the modifications to their assessment and valuation processes needed, and the contextual components for rare-disease evaluation that lie outside of the assessment framework as a guide to US decision makers on constructing a formal and relevant process stateside.  相似文献   
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Maternal and Child Health Journal - Objective The association between and commonality of risk factors for poor self-rated oral health (SROH) and general health (SRGH) among new mothers has not been...  相似文献   
90.
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