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141.
142.
Chronic mild stress in rats is an antidepressant-responsive model for anhedonic symptoms of major depression. Many patients with depression exhibit alterations in hypothalamic-pituitary-adrenal axis activity, and corticotropin-releasing factor (CRF) neuronal function. This study investigated the potential involvement of CRF and CRF receptors in the development of chronic mild stress-induced anhedonia in rats. Rats were subjected to 19 days of chronic mild stress, during which time anhedonia was periodically assessed by determining the threshold for self-stimulation of the ventral tegmental area. Anhedonic rats exhibited a 50% increase in CRF concentrations in the bed nucleus of the stria terminalis compared to control rats. There were no significant changes in hypothalamic-pituitary-adrenal axis activity, CRF or CRF(1) receptor mRNA expression, or CRF receptor binding in the brain regions analyzed. Though preliminary, these results are consistent with the hypothesis that chronic stress-induced modulation of CRF function in specific brain structures such as the bed nucleus of the stria terminalis may contribute to the pathophysiology of depression.  相似文献   
143.
Bronchiolitis-associated hospitalizations among US children, 1980-1996.   总被引:25,自引:1,他引:24  
D K Shay  R C Holman  R D Newman  L L Liu  J W Stout  L J Anderson 《JAMA》1999,282(15):1440-1446
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144.
Examination of the change strategies associated with successful long-term sobriety remains an understudied area in addiction research. The following study recruited individuals with long-term sobriety (range 16–25 years continuous abstinence). Subjects (n = 11) were surveyed on demographic information, problem history, Alcoholics Anonymous (AA) affiliation, and helping behaviors within several life domains over the course of sobriety. General helping behaviors increased from lower levels in the month prior to getting sober, to moderate levels at 1 year of sobriety, but did not continue to increase with additional years of sobriety. Levels of general help to others at home, work, and 12-step programs were similar at varying lengths of sobriety. Whereas overall levels of general help given to others were similar across settings, helping other alcoholics, as opposed to helping others at home or work, was rated as contributing the most to staying sober. Across time, alcoholics increased participation in helping behaviors specific to 12-step programs. The utility of helping others as a behavioral strategy to maintain successful addictive behavioral change is discussed.  相似文献   
145.
The distribution volume (DV) of 6-[F-18]fluoro-L-DOPA (FDOPA) in the cerebellum recently has been linked using positron emission tomography (PET) to plasma large neutral amino acid (LNAA) concentrations in monkeys. In this article the authors provide additional experimental support for this relation by directly measuring the DV as the steady-state tissue to plasma radioactivity ratio in rats using a labeled LNAA analog 3-O-methyl-6-[F-18]FDOPA (OMFD), a compound that has no known specific enzyme or receptor interactions in brain tissue. The measured DV for OMFD (tissue OMFD concentration/plasma OMFD concentration) was found to be inversely related to plasma LNAA concentrations. The relation (DV = 1.5-0.00094*[LNAA], R--2 = 0.79) resulted in an 8% DV decrease per 100 nmol/mL plasma LNAA increase within the observed range of 330 to 510 nmol/mL. This was similar to recent noninvasive observations with FDOPA PET in vervet monkeys and with 6-[F-18]Fluoro-m-tyrosine PET in squirrel monkeys. The OMFD striatum to cerebellum (Str/Cb) ratio was greater than 1.0 for all measurements, averaging 1.09 +/- 0.04, and was approximately equal to the Str/Cb LNAA ratio of 1.12 +/- 0.05. This current study verifies the variation of DV of OMFD or FDOPA as a function of plasma LNAA concentrations and suggests the possibility of using OMFD for measuring cerebral LNAA noninvasively with PET.  相似文献   
146.
Researchers using spatial attention tasks have shown that anxious individuals are quick to orient to threatening information, but have difficulty disengaging attention from that location. We extended this line of research by investigating the influence of anxiety on attention across time rather than space. It was found that anxious words imbedded in a rapidly presented stream of distractors were correctly identified more often than neutral words, regardless of the emotional state of the participant. Having identified the first target in the stream, participants were able to detect a second target sooner when the first target was an anxious word and the participant was experiencing anxiety in comparison to conditions in which the first target was neutral or the participant was not anxious. The rapid recovery of the attentional system when there was emotional congruence between the state of the individual and the attended information, points to the unique influence that anxiety has on attention across time in comparison to its influence on spatial attention.  相似文献   
147.
A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent.  相似文献   
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BACKGROUND: The role of rectal carriage of Staphylococcus aureus as a risk factor for nosocomial S. aureus infections in critically ill patients has not been fully discerned. METHODS: Nasal and rectal swabs for S. aureus were obtained on admission and weekly thereafter until discharge or death from 204 consecutive patients admitted to the surgical intensive care unit and liver transplant unit RESULTS: Overall, 49.5% (101 of 204) of the patients never harbored S. aureus, 21.6% (44 of 204) were nasal carriers only, 3.4% (7 of 204) were rectal carriers only, and 25.5% (52 of 204) were both nasal and rectal carriers. Infections due to S. aureus developed in 15.7% (32 of 204) of the patients; these included 3% (3 of 101) of the non-carriers, 18.2% (8 of 44) of the nasal carriers only, 0% (0 of 7) of the rectal carriers only, and 40.4% (21 of 52) of the patients who were both nasal and rectal carriers (P - .001). Patients with both rectal and nasal carriage were significantly more likely to develop S. aureus infection than were those with nasal carriage only (odds ratio, 3.9; 95% confidence interval, 1.18 to 7.85; P= .025). By pulsed-field gel electrophoresis, the infecting rectal and nasal isolates were clonally identical in 82% (14 of 17) of the patients with S. aureus infections. CONCLUSIONS: Rectal carriage represents an underappreciated reservoir for S. aureus in patients in the intensive care unit and liver transplant recipients. Rectal plus nasal carriage may portend a greater risk for S. aureus infections in these patients than currently realized.  相似文献   
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