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排序方式: 共有3812条查询结果,搜索用时 15 毫秒
61.
The effects of prenatal alcohol exposure on radial arm maze performance in adult rats 总被引:1,自引:0,他引:1
The hippocampal formation is sensitive to the in utero exposure to ethanol. It is one brain area thought to play an important role in spatial memory. We examined radial arm maze performance in rats exposed to ethanol prenatally. Pregnant rats were placed into the following treatment groups: LC, 17% EDC (ethanol-derived calories), 35% EDC, PF 35% or PF 17%. The LC group was fed lab chow and water ad lib, the 17% EDC and 35% EDC groups were fed a liquid diet containing either 3.3% or 6.7% v/v ethanol, respectively. Pair-fed controls were fed the same volume of an isocaloric diet as was consumed by their respective ethanol-treated groups. At birth, litters were culled to six and cross fostered to untreated surrogate mothers. Testing was initiated at 60 days of age and continued until the test criterion was satisfied. One-half of the rats in the 35% EDC group did not reach criterion. The remainder of the 35% EDC group and the 17% EDC rats attained criterion but required twice as many trials as their respective pair-fed controls. These results suggest that in utero administration of ethanol affects spatial memory capacity in rat, an observation consistent with other deficits seen in hippocampus of rats prenatally exposed to ethanol. 相似文献
62.
A "pseudo-pseudo" aneurysm of the left ventricle due to mid-ventricular obstruction from asymmetric septal hypertrophy is presented. A case of mid-ventricular hypertrophic obstructive cardiomyopathy (MVHOCM) was evaluated by means of echocardiography, angiocardiography, gated cardiac blood pool scanning, and a TI-201 myocardial scan. The gated cardiac blood pool scan appearance of MVHOCM is similar to pseudoaneurysm of the left ventricle. TI-201 myocardial imaging, however, was able to distinguish between MVHOCM and pseudoaneurysm of the left ventricle. 相似文献
63.
Frederick H Koh Jason MW Chua Joselyn LJ Tan Fung-Joon Foo Winson J Tan Sharmini S Sivarajah Leonard Ming Li Ho Bin-Tean Teh Min-Hoe Chew 《World journal of gastrointestinal surgery》2021,13(8):734-755
A growing body of evidence has demonstrated the prognostic significance of sarcopenia in surgical patients as an independent predictor of postoperative complications and outcomes. These included an increased risk of total complications, major complications, re-admissions, infections, severe infections, 30 d mortality, longer hospital stay and increased hospitalization expenditures. A program to enhance recovery after surgery was meant to address these complications; however, compliance to the program since its introduction has been less than ideal. Over the last decade, the concept of prehabilitation, or “pre-surgery rehabilitation”, has been discussed. The presurgical period represents a window of opportunity to boost and optimize the health of an individual, providing a compensatory “buffer” for the imminent reduction in physiological reserve post-surgery. Initial results have been promising. We review the literature to critically review the utility of prehabilitation, not just in the clinical realm, but also in the scientific realm, with a resource management point-of-view. 相似文献
64.
MW Lieberman R Barrios G Kala SV Kala ED Lykissa CN Ou 《Environmental health perspectives》1999,107(9):A444-A445
Respond on comments on Lieberman's article: Cyclosiloxanes Produce Fatal Liver and Lung Damage in Mice. Environ Health Perspect 107:161-165 相似文献
65.
MR imaging of human brain at 3.0 T: preliminary report on transverse relaxation rates and relation to estimated iron content 总被引:5,自引:0,他引:5
Gelman N Gorell JM Barker PB Savage RM Spickler EM Windham JP Knight RA 《Radiology》1999,210(3):759-767
PURPOSE: To determine the transverse relaxation rates R2 and R2' from several gray matter regions and from frontal cortical white matter in healthy human brains in vivo and to determine the relationship between relaxation rates and iron concentration [Fe]. MATERIALS AND METHODS: Six healthy adults aged 19-42 years underwent thin-section gradient-echo sampling of free induction decay and echo magnetic resonance (MR) imaging at 3.0 T. Imaging covered the mesencephalon and basal ganglia. RESULTS: Relaxation rates (mean +/- SD) were highest in globus pallidus (R2 = 25.8 seconds-1 +/- 1.1, R2' = 12.0 seconds-1 +/- 2.1) and lowest in prefrontal cortex (R2 = 14.4 seconds-1 +/- 1.8, R2' = 3.4 seconds-1 +/- 1.1). Frontal white matter measurements were as follows: R2 = 18.0 seconds-1 +/- 1.2 and R2' = 3.9 seconds-1 +/- 1.2. For gray matter, both R2 and R2' showed a strong correlation (r = 0.92, P < .001 and r = 0.90, P < .001, respectively) with [Fe]. Although the slopes of the regression lines for R2' versus [Fe] and for R2 versus [Fe] were similar, the iron-independent component of R2' (2.2 seconds-1 +/- 0.6), the value when [Fe] = 0, was much less than that of R2 (12.7 seconds-1 +/- 0.7). CONCLUSION: The small iron-independent component R2', as compared with that of R2, is consistent with the hypothesis that R2' has higher iron-related specificity. 相似文献
66.
BACKGROUND AND PURPOSE: The Pfannenstiel incision provides good access to the bladder and bladder neck for major reconstructive surgery in the thin patient, whereas a midline incision is often necessary to get adequate exposure in the obese patient. We describe our experience using laparoscopic-assisted continent urinary diversion in conjunction with other bladder and bladder neck surgery in obese patients. PATIENTS AND METHODS: Three female patients (mean age 18; mean weight 175 pounds) with neurogenic bladder underwent Mitrofanoff appendicovesicostomy continent urinary diversion to the umbilicus and pubovaginal sling. An umbilical port for the telescope and two lateral ports were used. Once the appendix and right hemicolon had been completely mobilized up to the hepatic flexure, reconstruction was completed through a low Pfannenstiel incision. RESULTS: There were no laparoscopic complications. None of the laparoscopic port sites was visible postoperatively, as one was in the base of the umbilicus, and the other two had been incorporated into the Pfannenstiel incision. With a mean follow-up of 1 year, all patients were continent and catheterizing their umbilicus easily. Pfannenstiel incisions were well healed, and the patients were quite satisfied with their cosmesis. CONCLUSION: Laparoscopic-assisted Mitrofanoff appendicovesicostomy continent urinary diversion to the umbilicus can be performed in conjunction with a Pfannenstiel incision to complete major bladder and bladder neck surgery in the obese patient with good postoperative cosmesis. This procedure represents a nice compromise between a very lengthy bladder reconstructive procedure done purely laparoscopically and a midline incision with good exposure but suboptimal cosmesis. 相似文献
67.
Heckers S Goff D Schacter DL Savage CR Fischman AJ Alpert NM Rauch SL 《Archives of general psychiatry》1999,56(12):1117-1123
BACKGROUND: Neuroimaging studies have provided evidence of abnormal frontal and temporal lobe function in schizophrenia. Frontal cortex abnormalities have been associated with negative symptoms and temporal lobe abnormalities with positive symptoms. The deficit and nondeficit forms of schizophrenia were predicted to differ in prefrontal cortical activity, but not in medial temporal lobe activity. METHODS: Regional cerebral blood flow was studied using oxygen 15 positron emission tomography during 3 different memory retrieval conditions in 8 control subjects, 8 patients with the deficit syndrome, and 8 patients without the deficit syndrome. Behavioral and positron emission tomography data were analyzed using a mixed-effects model to test for population differences. RESULTS: In all memory conditions, frontal cortex activity was higher in patients without the deficit syndrome than in patients with the deficit syndrome. During the attempt to retrieve poorly encoded words, patients without the deficit syndrome recruited the left frontal cortex to a significantly greater degree than did patients with the deficit syndrome. The 2 schizophrenia subtypes did not differ in the activity or recruitment of the hippocampus during memory retrieval. CONCLUSION: Frontal cortex function during memory retrieval is differentially impaired in deficit and nondeficit schizophrenia, whereas hippocampal recruitment deficits are not significantly different between the 2 schizophrenia groups. 相似文献
68.
Suicide in the course of the treatment of depression 总被引:3,自引:0,他引:3
Five different mechanisms have been proposed whereby antidepressant treatment might lead to suicide: first by simply ameliorating depressions more rapidly; second by an action intrinsic to the specific antidepressant effects; third by toxicity in overdose; fourth by side-effects of specific antidepressants; and finally by virtue of treatment inefficacy. Evidence from randomized control trials (RCT), controlled case studies and epidemiological studies on this question is reviewed and it is concluded that antidepressants can be implicated in some cases of suicide during treatment. Modifications of clinical trial methods and pharmacogenetic studies would yield a richer data set to explore this issue further. 相似文献
69.
V. Pillay N. Savage H. Laburn 《Pflügers Archiv : European journal of physiology》1993,425(5-6):549-551
We have used patch-clamp techniques to study the effect of the sulfhydryl group oxidizing agents mercury and thimerosal on calcium-activated nonselective cation channels from brown adipose tissue. 100 nmol/l mercury and 50 mol/l thimerosal induced a complete block. Blockade could be reversed by reduction of the mercaptide by dithiotreitol (DTT). Mercury was found to be the most potent blocker (IC50-value 21×10–9 mol/l), whereas thimerosal (IC50-value 1.5×10–6 mol/l) was as effective as 3,5-dichlorodiphenylamine-2-carboxylic acid (DCDPC). The DCDPC effect, however, could not be reversed by DTT, indicating different blocking mechanisms. It is concluded that SH-groups are involved in gating of the calcium-activated nonselective channel. 相似文献
70.
Poison Centers frequently rely on the assistance of local plant nurseries to identify unknown plants involved in exposures. The reliability and accuracy of utilizing this method has never been studied; therefore, our objective was to evaluate this primary resource of plant identification. A study was done in which callers were instructed to take plant samples to a local nursery for visual identification. Once the patient was treated according to our normal protocol, the plant specimen was sent to a botanist for a second identification. The botanist provided his identification results through a blinded process. The collected data was gathered from 68 cases that completed the necessary study criteria. In 58% of the cases, plant nurseries were an unreliable source for plant identification. These incorrect identifications resulted in the "undertreatment" in 24% of the exposures. 相似文献