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1.
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   

2.
目的:流行性肌痛性眼病(BED)包括X-连锁高度近视,高度散光,视神经发育不良,继发的异常光反应出现的视网膜电流图闪动,以及绿色盲。该病定位于染色体Xq28,并且被最早认为是高度近视位点(MYPl)。我们研究了来自明尼苏达的一个家族,具有相似X连锁的基因显型,并且具有丹麦血统。所有被影响的男性均为红色盲而不是绿色盲。  相似文献   
3.
A drinking water supply is a complicated system in its construction,operation,maintenance and need for public health surveillance.  相似文献   
4.
A new type of pseudodipeptide isostere exampled by Phe ψ[CH2CH(OH)]Phe was synthesized from phenylalanine. The H]V protease inhibitory activity (IC50) of Noa-His-Pheψ[CH2CH(OH)]Phe-Ile-Amp was 0. 8 pmol·L-1.  相似文献   
5.
The effect of intermittent courses of recombinant interleukin-2 (rIL-2) on HIV-1 load in patients receiving combination antiretroviral therapy remains uncertain. CPCRA 059 was an open-label, randomized, multicenter trial in which 511 patients with HIV-1 infection and CD4+ cell counts of > or = 300/mm3 who were receiving antiretroviral therapy were assigned to receive no rIL-2 (255 patients [controls]) or subcutaneous rIL-2 in dosages of 4.5 MIU (130) or 7.5 MIU (126) twice daily for 5-day courses every 8 weeks to maintain CD4+ cell counts that were twice the baseline value or > or = 1,000/mm3. The primary objective of this study was to compare the effects of the two doses of rIL-2 and no rIL-2 on viral load and CD4+ cell counts over 12 months. There was no difference in the following viral load measurements between the rIL-2 treatment groups and the control treatment group: percentage of patients with viral loads of <50 copies/mL at 12 months (p =.55), time to viral load of > or = 50 copies/mL for patients who had baseline viral loads of <50 copies/mL (p =.35), and change in viral load from baseline for patients who had viral loads of > or = 50 copies/mL at baseline (p =.63). At each follow-up visit, the change in CD4+ cell count from baseline was significantly greater in the rIL-2 treatment groups than in the control treatment group, with a mean difference of 251/mm3 at month 12 (95% confidence interval, 207-295; p <.0001). No unanticipated adverse experiences were seen in this trial, to our knowledge the largest randomized evaluation of rIL-2 treatment conducted to date.  相似文献   
6.
7.
Emerging electronic health record models present numerous challenges to health care systems, physicians, and regulators. This article provides explanation of some of the reasons driving the development of the electronic health record, describes two national electronic health record models (currently developing in the United States and Australia) and one distributed, personal model. The US and Australian models are contrasted in their different architectures ("pull" versus "push") and their different approaches to patient autonomy, privacy, and confidentiality. The article also discusses some of the professional, practical, and legal challenges that health care providers potentially face both during and after electronic health record implementation.  相似文献   
8.
In myotonic dystrophy type 1 (DM1), an expanded CTG repeat shows repeat size instability in somatic and germ line tissues with a strong bias toward further expansion. To investigate the mechanism of this expansion bias, 29 DM1 and six normal lymphoblastoid cell lines (LBCLs) were single-cell cloned from blood cells of 18 DM1 patients and six normal subjects. In all 29 cell lines, the expanded CTG repeat alleles gradually shifted toward further expansion by "step-wise" mutations. Of these 29 cell lines, eight yielded a rapidly proliferating mutant with a gain of large repeat size that became the major allele population, eventually replacing the progenitor allele population. By mixing cell lines with different repeat expansions, we found that cells with larger CTG repeat expansion had a growth advantage over those with smaller expansions in culture. This growth advantage was attributable to increased cell proliferation mediated by Erk1,2 activation, which is negatively regulated by p21(WAF1). This phenomenon, which we designated "mitotic drive" , is a novel mechanism which can explain the expansion bias of DM1 CTG repeat instability at the tissue level, on a basis independent of the DNA-based expansion models. The lifespans of the DM1 LBCLs were significantly shorter than normal cell lines. Thus, we propose a hypothesis that DM1 LBCLs drive themselves to extinction through a process related to increased proliferation.  相似文献   
9.
The present study examined further the pharmacological specificity of the methylxanthine CNS stimulant caffeine as a discriminative stimulus in humans. Nine normal healthy volunteers (ages 19-39) were trained to discriminate between caffeine (320mg/70kg, p.o.) and placebo, using monetary reinforcement of correct letter code identification. After four training sessions, subjects were tested with the training conditions until they were >80% correct on four consecutive sessions. Then dose-effect curves were determined for caffeine (56-320mg/70kg), theophylline (56-320mg/70kg), methylphenidate (10-56mg/70kg), and buspirone (1-32mg/70kg). Seven of nine subjects met the discrimination criterion within four to nine sessions. During dose-effect curve determinations, caffeine and methylphenidate each produced dose-related increases in caffeine-appropriate responding. Theophylline produced caffeine-appropriate responding that was not dose related in a consistent manner across subjects, occasioning an average of 50% caffeine-appropriate responding at most doses tested. Buspirone produced predominantly placebo-appropriate responding. Caffeine-appropriate responding tended to be directly related to ARCI LSD scores, self-reported "bad" effects, "high", and stimulant-bad effects and inversely related to ARCI PCAG scores and sedative ratings. These results agree with non-human data and suggest that the caffeine discriminative stimulus has pharmacological specificity, in that caffeine-appropriate responding generalizes to other stimulants such as theophylline or methylphenidate, but not to non-stimulant compounds such as buspirone.  相似文献   
10.
Sacramento, California's capital, represents the nation's most competitive managed care marketplace. The Sutter Health organization represents a significant force in this marketplace and surrounding regions of Northern California. Sutter has created an integrated regional health care network capable of delivering a full continuum of care through appropriate community-based facilities, a variety of physician relationships, and both owned and aligned managed care structures. The overall Sutter Health strategy that incorporates facilities, physician partnerships, and patient care financing is described. The article identifies six key lessons learned during this period of growth.  相似文献   
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