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991.

BACKGROUND:

In an era of increasingly shortened admissions, data regarding predictors of early rebleeding among patients with nonvariceal upper gastrointestinal bleeding (NVUGIB) exhibiting high-risk stigmata (HRS) having undergone endoscopic hemostasis are lacking.

OBJECTIVES:

To determine predictors of early rebleeding, defined as rebleeding before completion of recommended 72 h intravenous proton pump inhibitor infusion postendoscopic hemostasis.

METHODS:

Data from a national registry of patients with upper gastrointestinal bleeding (the REASON registry) were accessed. Univariable and multivariable analyses were sequentially performed to identify significant independent predictors among a comprehensive list of clinical and laboratory characteristics.

RESULTS:

Overall, 393 patients underwent endoscopic hemostasis for NVUGIB with HRS. Forty patients rebled ≤72 h thereafter (32.5% female, mean [± SD] age 70.2±11.8 years, 2.88±2.11 comorbidities), while 21 rebled later (38.1% female, mean 70.5±14.1 years of age, 2.62±2.06 comorbidities). Hematemesis or bright red blood per nasogastric tube aspirate was identified as the sole independent significant predictor of early rebleeding versus later among both NVUGIB and, more specifically, patients with peptic ulcer bleeding (OR 7.94 [95% CI 1.80 to 35.01]; P<0.01, and OR 8.41 [95% CI 1.54 to 46.10]; P=0.014, respectively).

CONCLUSIONS:

When attempting to determine the optimal duration of pharmacotherapy and timing of discharge for patients following endoscopic hemostasis for NVUGIB with HRS, it is noteworthy that individuals who present with hematemesis or bright red blood per nasogastric tube aspirate are at particularly high risk for rebleeding within the first 72 h.  相似文献   
992.
Pediatric syncope accounts for 3% of the consultations in emergency department. It is frequent in pediatrics, particularly in teenager girls between 15 and 19 years old, and up to a 25% of them have suffered from a syncopal episode. Most causes are benign, but the aim in its initial evaluation is ruling out those which mean any danger. Heart disease can lead to syncope in a 10-28% of cases. A detailed medical history and an exhaustive exploration are enough to rule out organic pathology in most situations. We present the case of a diffuse large B cell lymphoma located in the mediastinum diagnosed after repetitive syncopal episodes.  相似文献   
993.
994.
Despite huge advances on Alzheimer's disease (AD) etiology, the clinical diagnosis remains the unique commonly used tool to detect the onset of the disease. For instance, epidemiological studies report that the combination of episodic and working memory disorders represents the most consistent sign of progression from mild cognitive impairment to AD. However, such working memory disorders failed to be observed early in transgenic mouse models of AD because the behavioral procedures used do not tackle properly crucial components of working memory. The aim of the present work was to assess early occurrence of working memory impairments in APP(751SL) mice. Therefore, we designed a new behavioral task in the water-maze, based on the principle of a delayed matching to place task, where spatial recognition was assessed for four different platform locations within a single session. First, we showed that dorsal hippocampal but not medial prefrontal cortex lesions in C57Bl6 mice induced a time-dependent impairment of spatial recognition. Then, the hippocampal-like memory alterations were reproduced in 7-8-month-old APP(751SL) mice but not in younger animals (5-6-month-old). We also demonstrated that these working memory deficits are related to progressive Aβ accumulation in the hippocampus, but not in the other selected brain structures.  相似文献   
995.
Since zinc transporter ZnT3 is localized to the hippocampus and perirhinal cortex, we used ZnT3 knockout mice (KO) to analyze the role of ZnT3 in memory and behavior dependent on these brain regions. ZnT3KO mice were normal in initial learning in the standard water maze but had difficulty finding a second platform location. The mutants showed increased social interaction but were deficient in social and object recognition memory. These data suggest that ZnT3 is involved in certain types of spatial memory and behavior dependent on the hippocampus and perirhinal cortex.  相似文献   
996.
997.
998.
IntroductionWe have recently reported that dehydroepiandrosterone (DHEA) increases the density of nerve fibers in the ovariectomized (OVX) rat vagina.AimTo better define the mechanism of action of DHEA, we have examined the effect of DHEA, conjugated estrogens (premarin) and the potent blocker of estrogen action acolbifene on the innervation in the lamina propria in the OVX rat vagina.MethodsFemale Sprague‐Dawley rats (10–12 weeks old) were used. Innervation of the vagina was examined 9 months after OVX and was compared to that of OVX animals treated daily with DHEA (80 mg/kg) by topical application on the skin, premarin (0.5 mg/kg) orally as well as acolbifene (2.5 mg/kg) orally administrated alone or in combination with DHEA or premarin.Main Outcome MeasuresFour histological sections from each vagina (5 animals/group) were immunostained using antibodies to the panneuronal marker protein gene product 9.5 (PGP 9.5). The areas were measured by stereological analysis.ResultsOVX reduced the area of the lamina propria to 44% of the intact value, an effect which was reversed to 69% and 84% of the intact value by DHEA and premarin, respectively, at the doses used. When acolbifene was used, no inhibition of the stimulatory effect of DHEA was observed, while the action of premarin was completely blocked. Evaluation of the PGP 9.5 fiber density revealed that DHEA treatment increased the density of fibers by 60% compared to OVX animals, while a further 27% increase was observed when acolbifene was combined with DHEA. Premarin, on the other hand, had no effect on the density of PGP 9.5 fibers.ConclusionsConsidering that the antiestrogen acolbifene had no inhibitory effect on the effect of DHEA in rat vagina while blocking the stimulatory effect of premarin, the present data indicate that DHEA exerts its stimulatory effect on the fiber density through an androgenic action. Pelletier G, Ouellet J, Martel C, and Labrie F. Androgenic action of dehydroepiandrosterone (DHEA) on nerve density in the ovariectomized rat vagina. J Sex Med 2013;10:1908–1914.  相似文献   
999.
The working party statements aim to provide evidence and guidelines to practising doctors on the use of antiplatelet therapy and proton pump inhibitors (PPIs) in patients with cardiovascular risk as well as those at risk of gastrointestinal (GI) bleeding. Balancing the GI and cardiovascular risk and benefits of antiplatelet therapy and PPIs may sometimes pose a significant challenge to doctors. Concomitant use of anti‐secretory medications has been shown to reduce the risk of GI bleeding but concerns have been raised on the potential interaction of PPIs and clopidogrel. Many new data have emerged on this topic but some can be confusing and at times controversial. These statements examined the supporting evidence in four main areas: rationale for antiplatelet therapy, risk factors of GI bleeding, PPI–clopidogrel interactions and timing for recommencing antiplatelet therapy after GI bleeding, and made appropriate recommendations.  相似文献   
1000.

Objectives

To evaluate, for individuals with chronic stroke with cognitive impairment, (1) the effects of a practice test on peak cardiorespiratory fitness test results; (2) cardiorespiratory fitness test-retest reliability; and (3) the relationship between individual practice test effects and cognitive impairment.

Design

Cross-sectional.

Setting

Rehabilitation center.

Participants

A convenience sample of 21 persons (men [n=12] and women [n=9]; age range, 48–81y; 44.9±36.2mo poststroke) with cognitive impairments who had sufficient lower limb function to perform the test.

Interventions

Not applicable.

Main Outcome Measure

Peak oxygen consumption (Vo2peak, ml·kg−1·min−1).

Results

Test-retest reliability of Vo2peak was excellent (intraclass correlation coefficient model 2,1 [ICC2,1]=.94; 95% confidence interval [CI], .86–.98). A paired t test showed that there was no significant difference for the group for Vo2peak obtained from 2 symptom-limited cardiorespiratory fitness tests performed 1 week apart on a semirecumbent cycle ergometer (test 2–test 1 difference, −.32ml·kg−1·min−1; 95% CI, −.69 to 1.33ml·kg−1·min−1; P=.512). Individual test-retest differences in Vo2peak were, however, positively related to general cognitive function as measured by the Mini-Mental State Examination (ρ=.485; P<.026).

Conclusions

Vo2peak can be reliably measured in this group without a practice test. General cognitive function, however, may influence the effect of a practice test in that those with lower general cognitive function appear to respond differently to a practice test than those with higher cognitive function.  相似文献   
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