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1.
Various cases are presented demonstrating the role of computed tomography (CT) in the assessment of serosal and bowel wall pathology. Reference is made to the morphology of the lesions. Illustrative examples of tumors, secondary malignant dissemination, irradiation injury to the gut, and intramural gas associated with ulcerative colitis, are all illustrated. 相似文献
2.
Davangere P Devanand Christian G Habeck Matthias H Tabert Nikolaos Scarmeas Gregory H Pelton James R Moeller Brett D Mensh Tyler Tarabula Ronald L Van Heertum Yaakov Stern 《Neuropsychopharmacology》2006,31(6):1327-1334
Temporoparietal and posterior cingulate metabolism deficits characterize patients with Alzheimer's disease (AD). A H(2)(15)O resting PET scan covariance pattern, derived by using multivariate techniques, was previously shown to discriminate 17 mild AD patients from 16 healthy controls. This AD covariance pattern revealed hypoperfusion in bilateral inferior parietal lobule and cingulate; and left middle frontal, inferior frontal, precentral, and supramarginal gyri. The AD pattern also revealed hyperperfusion in bilateral insula, lingual gyri, and cuneus; left fusiform and superior occipital gyri; and right parahippocampal gyrus and pulvinar. In an independent sample of 23 outpatients with mild cognitive impairment (MCI) followed at 6-month intervals, the AD pattern score was evaluated as a predictor of cognitive decline. In this MCI sample, an H2(15)O resting PET scan was carried out at baseline. Mean duration of follow-up was 48.8 (SD 15.5) months, during which time six of 23 MCI patients converted to AD. In generalized estimating equations (GEE) analyses, controlling for age, sex, education, and baseline neuropsychological scores, increased AD pattern score was associated with greater decline in each neuropsychological test score over time (Mini Mental State Exam, Selective Reminding Test delayed recall, Animal Naming, WAIS-R digit symbol; Ps<0.01-0.001). In summary, a resting PET covariance pattern previously reported to discriminate AD patients from control subjects was applied prospectively to an independent sample of MCI patients and found to predict cognitive decline. Independent replication in larger samples is needed before clinical application can be considered. 相似文献
3.
Efficient 12-mutation testing in the CFTR gene: a general model for complex mutation analysis 总被引:12,自引:4,他引:8
Shuber Anthony P.; Skoletsky Joel; Stern Robert; Handelin Barbara L. 《Human molecular genetics》1993,2(2):153-158
The identification of the cystic fibrosis transmembrane conductanceregulator (CFTR) gene has led to the identification of morethan 225 presumed disease-causing mutations at the locus. Thediagnosis of cystic fibrosis or the carrier state by directDNA analysis is hindered by this large number. A practical assaymust be able to detect enough mutations to achieve clinicallysignificant sensitivity. The use of allele-specifk oligonucleotideprobes is the most promising of the available methods. However,to date this has generally involved tedious probe-by-probe hybridizations,due to variations in the oligonucleotides' denaturation temperaturescaused by differences in their G-C base-pair content. We havedeveloped a rapid, cost-effective assay that simultaneouslydetects 12 CFTR mutations after multiplex polymerase-chain-reactionamplification of genomic DNA. The test may be readily extendedto detect additional mutations at minimal increase in the costper test or the turnaround time. We improve specificity andavoid the need for individual hybridizations by the use of tetramethylammoniumchloride to virtually eliminate the effects of G-C differences.Coupled with non-invasive sample-collection methods, this isan immediately practical assay for cystic fibrosis. More generally,it will serve as a model for the development of diagnostic testsin other genetic disorders involving complex mutation analysis. 相似文献
4.
H. S. Markus A. M. Tomkins G. M. Stern 《Journal of neural transmission (Vienna, Austria : 1996)》1993,5(2):117-125
Summary An anthropometric study was performed in 95 subjects (53 male, 42 female) with Parkinson's disease. Weight, height, triceps and biceps skin-fold thicknesses, and mid-arm circumference were recorded. A high incidence of undernutrition was found (23.6% of males and 22.5% of females, as defined by recent British guidelines). A subgroup of severely disabled patients with Parkinson's disease had a significantly lower mean body mass index than a similarly disabled control group with chronic pyramidal upper motor neuron lesions (males 20.6v 23.2 kg/m2 p<0.05; females 20.6v 26.6 kg/m2 p<0.01), suggesting that the undernutrition is not due to chronic illness or immobility alone. Correlation between anthropometric indices and clinical features of disease demonstrated that the presence of moderate or severe dyskinetic movements was the clinical parameter most strongly related to undernutrition. The reduction in anthropometric indices was most marked for skin fold thickness (related to percentage body fat) and least for arm muscle circumference (related to lean body mass); therefore the weight loss seen in Parkinson's disease is primarily due to fat loss rather than muscle loss. 相似文献
5.
6.
Effects of Ethanol in an Experimental Model of Combined Traumatic Brain Injury and Hemorrhagic Shock 总被引:3,自引:2,他引:1
Brian J. Zink MD Susan A. Stern MD Xu Wang MD Carl C. Chudnofsky MD 《Academic emergency medicine》1998,5(1):9-17
Objectives: Given that clinical and laboratory studies suggest that ethanol and hemorrhagic shock (HS) potentiate traumatic brain injury (TBI), the authors studied the effects of ethanol in a model of combined TBI and HS.
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O2 saturation in the postinjury period. Cerebral O2 extraction ratios and cerebral venous lactate levels were significantly higher in the ethanol group. A trend toward lower postinjury rCBF in all brain regions was observed in the ethanol group.
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion. 相似文献
Methods: A controlled porcine model of combined TBI and HS was evaluated for the effect of ethanol on survival time, hemodynamic function, and cerebral tissue perfusion. Anesthetized swine (17–24 kg) were instrumented, splenectomized, and subjected to fluid percussion TBI with concurrent 25-mL/kg graded hemorrhage over 30 minutes. Two groups were studied: control ( n = 11) and ethanol ( n = 11). Ethanol, 3.5 g/kg intragastric, was given 100 minutes prior to TBI/HS. Systemic and cerebral physiologic and metabolic parameters were monitored for 2 hours without resuscitation. Regional cerebral blood flow (rCBF) and renal blood flow were measured with dye-labeled microspheres. Data were analyzed with 2-sample t-test and repeated-measures ANOVA.
Results: Ethanol levels at the time of injury were 162 ± 68 mg/dL. Average TBI was 2.65 ± 0.35 atm. Survival time was significantly shorter in the ethanol group (60 ± 27 min vs 94 ± 28 min, p = 0.011). The ethanol group had significantly lower mean arterial pressure, cerebral perfusion pressure, and cerebral venous
O
Conclusion: In this TBI/HS model, ethanol administration decreased survival time, impaired the hemodynamic response, and worsened measures of cerebral tissue perfusion. 相似文献
7.
8.
The effect of benserazide on the peripheral and central distribution and metabolism of levodopa after acute and chronic administration in the rat.
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1. The effects of levodopa alone (50 mg kg-1) and levodopa (10 mg kg-1) plus benserazide (50 mg kg-1) were tested on the levels of dopa, dopamine, 3-methoxytyrosine (3-MT), 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), measured by h.p.l.c. with electrochemical detection, in samples of plasma, CSF, urine, striatum and hypothalamus of rats taken 30 min after injection. Levodopa plus benserazide produced significantly higher levels of dopa in plasma and brain than levodopa alone and reduced the peripheral synthesis and metabolism of dopamine. 2. When given chronically over 6 weeks the advantages of adding benserazide (50 mg kg-1 day-1) to levodopa (40 mg kg-1 day-1) were less marked and although more dopamine was present in the striatum than with levodopa given alone (200 mg kg-1 day-1) there was no evidence of any increase in its metabolites (HVA and DOPAC) and therefore of its turnover and utilisation. 3. The most striking effect of chronic treatment with levodopa plus benserazide was the appearance of large quantities of 3-MT in plasma, CSF and brain. 4. When levodopa alone, or levodopa plus benserazide, was given as an acute challenge to animals receiving the same treatment chronically, it was found that levodopa alone still produced increases in striatal dopamine, DOPAC and HVA in those animals dosed chronically on levodopa, but it was less effective in this respect when given with benserazide to the animals dosed with levodopa plus benserazide.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
9.
Richard J Levy Whitney B Stern Kimberly I Minger Lisa M Montenegro Chitra Ravishankar Jonathan J Rome Susan C Nicolson David R Jobes 《Pediatric critical care medicine》2005,6(6):671-675
BACKGROUND: Mixed venous saturation (S & OV0456;o2) is an important measurement that helps guide the care of critically ill patients. Invasive S & OV0456;o2 assessment in infants and children is often avoided because of the inherent risks. A noninvasive tissue saturation (S to 2) monitor has recently been developed that uses near-infrared spectroscopy to measure oxyhemoglobin saturation in muscle. In adult and animal studies, S to 2 correlated with oxygen delivery and S & OV0456;o2. There has been no evaluation in pediatric patients. OBJECTIVE: To evaluate tissue saturation as a noninvasive measure of mixed venous saturation in children. DESIGN: A prospective observational study. SETTING: Catheterization laboratory in a tertiary care children's medical center. PATIENTS: We studied 98 children (49 without intracardiac mixing and 49 with intracardiac mixing) 相似文献
10.
Question: Is there a difference in cancer-related survival between laparoscopic assisted colectomy (LAC) and open colectomy (OC)? Design: Randomized controlled trial. Setting: Single-centre trial, Barcelona, Spain. Patients: Two hundred and nineteen of 442 eligible patients with adenocarcinoma of the colon were included. Patients were excluded if the tumour was below 15 cm from the anal verge or was in the transverse colon; if there were distant metastases, adjacent organ involvement or obstruction; or the patient had previous colonic surgery. One hundred and eleven were randomized to the LAC group and 108 to the OC. Interventions: Randomization was done the day before surgery. Patients were stratified into 2 groups according to tumour location (right or left side with respect to the splenic flexure) and assigned to the LAC or OC group by means of sealed opaque envelopes containing computer-generated random numbers. Patients in both groups had surgery by a single gastrointestinal surgical team. Pre- and postoperative care was standardized for bowel prep and perioperative antibiotics. Patients received either LAC or OC using a no-touch technique and initial vascular ligation. Main outcome measure: Overall survival. Results: The Cox model showed that LAC was independently associated with reduced risk of tumour relapse (hazard ratio 0.39, 95% CI 0.19 – 0.82), death from any cause (0.48, 0.23 –1.01) and death from a cancer-related cause (0.38, 0.16– 0.91) compared with OC. This superiority of LAC was due to differences in patients with stage III tumours (freedom from recurrence p = 0.04, overall survival p = 0.02, and cancer- related survival p = 0.006).
Conclusion:
LAC is more effective than OC for treatment in terms of morbidity, hospital stay, tumour recurrence and cancer-related survival. 相似文献