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131.
Correlated electron and light microscopic studies of the distribution, position, appearance, migration and fate of lymphocytes with relation to the intestinal epithelium of the young adult rat, mouse, hamster and man have been made. Under the conditions of this investigation, the lymphocytes which are normally present in the intestinal epithelium are intercellular in position, irrespective of their level within the epithelium. The great majority of these cells are located in the basal region of the epithelium, below the level of the epithelial cell nuclei. There was no evidence of lymphocytic degeneration. Lymphocytes migrated from the lamina propria into the epithelium and back again into the lamina propria, with no evidence of movement toward the free surface of the intestinal epithelium and extrusion into the lumen. 相似文献
132.
Processing of radical prostatectomy specimens for correlation of data from histopathological, molecular biological, and radiological studies: a new whole organ technique 下载免费PDF全文
Jhavar SG Fisher C Jackson A Reinsberg SA Dennis N Falconer A Dearnaley D Edwards SE Edwards SM Leach MO Cummings C Christmas T Thompson A Woodhouse C Sandhu S Cooper CS Eeles RA 《Journal of clinical pathology》2005,58(5):504-508
AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices. 相似文献
133.
Characterization of translational frame exception patients in Duchenne/Becker muscular dystrophy 总被引:8,自引:3,他引:8
Winnard Alissa V.; Klein Christopher J.; Coovert Daniel D.; Prior Thomas; Papp Audrey; Snyder Pamela; Bulman Dennis E.; Ray Peter N.; McAndrew Patricia; King Wendy; Moxley Richard T.; Mendell Jerry R.; Burghes Arthur H.M. 《Human molecular genetics》1993,2(6):737-744
The clinical progression of Duchenne muscular dystrophy (DMD)patients with deletions can be predicted in 93% of cases bywhether the deletion maintains or disrupts the translationalreading frame (frameshift hypothesis). We have identified andstudied a number of patients who have deletions that do notconform to the translational frame hypothesis. The most commonexception to the frameshift hypothesis is the deletion of exons3 to 7 which disrupts the translational reading frame. We identifieda Becker muscular dystrophy (BMD) patient, an intermediate,and a DMD patient with this deletion. In all three cases, dystrophinwas detected and localized to the membrane. One DMD patientwith an inframe deletion of exons 418 produced no dystrophin.One patient with a mild intermediate phenotype and a deletionof exon 45, which shifts the reading frame, produced no dystrophin.Two patients with large inframe deletions had discordant phenotypes(exons 341, DMD; exons 1348, BMD), but both produceddystrophin that localized to the sarcolemma. The DMD patient,113, indicates that dystrophin with an intact carboxy terminuscan be produced in Duchenne patients at levels equivalent tosome Beckers. The dystrophin analysis from these patients, togetherwith patients reported in the literature, indicate that morethan one domain can localize dystrophin to the sarcolemma. Lastely,the data shows that although most patients show correlationof clinical severity to molecular data, there are rare patientswhich do not conform. 相似文献
134.
G. C. Dennis B. Welch A. N. Cole R. Mendoza J. Morgan J. Epps E. Bernard P. St Louis 《Journal of the National Medical Association》1997,89(2):101-108
The clinical outcome of patients following subarachnoid hemorrhage is complicated by delayed cerebral ischemia and contributing factors such as hypertension. To observe the impact of hypertension and delayed cerebral ischemia on the outcome of a predominantly African-American cohort following subarachnoid hemorrhage, both retrospective (n = 42) and prospective (n = 21) studies were conducted. In the total pool (n = 63), the mean age was 49.7 years (range: 17 to 80) with a preponderance of female patients (70%). Aneurysm formation was significant in the region of the posterior communicating artery. Of the patients reviewed, 73.8% had preexisting hypertension and 45.9% developed delayed cerebral ischemia. Approximately 89% of the patients who suffered from delayed cerebral ischemia had hypertension. Results failed to display any significant beneficial association between the use of the calcium channel blocker nimodipine and delayed cerebral ischemia. Use of the antifibrinolytic drug aminocaproic acid demonstrated a worse patient outcome. It is not recommended that aminocaproic acid be used in this population. Subsequently, due to the proportional occurrence of delayed cerebral ischemia in hypertensive patients following subarachnoid hemorrhage, it is suggested that prophylactic surgical management of unruptured intracranial aneurysms be considered in hypertensive patients. Further study is needed to discern the association between hypertension, delayed cerebral ischemia, and stroke in patients following subarachnoid hemorrhage. 相似文献
135.
Mario Geller M.D. Dennis K. Flaherty Ph.D. Helen A. Dickie M.D. Charles E. Reed M.D. 《The Journal of allergy and clinical immunology》1977,59(6):445-448
Each of 5 patients with acute nitrofurantoin pleuropulmonary reactions had profound lymphopenia and 4 had eosinophilia developing early in the clinical course after the drug was withdrawn. The 2 patients tested had only one third of the normal numbers of E rosettes (T lymphocytes) in the peripheral blood during recovery. Lymphoblastic transformation tests with purified nitrofurantoin were done in 3 patients and all of them were negative; responses to phytohemagglutinin, concanavalin A, and pokeweed were decreased but still normal. The diagnosis of various nitrofurantoin hypersensitivity reactions relies on clinical data. The mechanisms of these reactions presently remain unclear. 相似文献
136.
Milk intake and nipple attachment behaviors were studied in the natural suckling situation after gastrointestinal preloading. Rat pups, deprived of their dam for 9 hr at 1, 10, or 20 days of age, were preloaded by gavage with volumes ranging from 2 to 16% of their body weight and returned to suckle. Preloads of artificial bitch's milk decreased the intake of mother's milk in a volume-related manner at all ages. At 1 and 10 days 4% preloads decreased milk intake without affecting attachment behaviors; larger prelods of 8 and 16% decreased intake and reduced the incidence of attachment. At 20 days of age small and large preloads decreased both incidence of attachment and milk intake. Preloads up to 8% of body weight had no effect on latency to attach at any age. Complete subdiaphragmatic bilateral vagotomy increased milk intake of 7–9–day-old pups fed automatically through an anterior mouth cannula in a nonsuckling situation. Vagotomy combined with spinal cordotomy (T2-T3) resulted in a synergistic hyperphagia and massive distension of the upper GI tract. The results indicate that suckling rats can control their intake of mother's milk while remaining attached to a nipple as early as 1 day of age. The suppression of ingestion in response to GI filling appears to be mediated by visceral afferent activity. Conversely, attachment behaviors are less affected by GI fill. This suggests that ingestive behaviors and attachment behaviors have different controls during the 1st 10 days of postnatal development. 相似文献
137.
Kevin D. Derman John A. Hawley Timothy D. Noakes Steven C. Dennis 《European journal of applied physiology》1996,74(1-2):36-43
On two occasions, six well-trained, male competitive triathletes performed, in random order, two experimental trials consisting of either a timed ride to exhaustion on a cycle ergometer or a run to exhaustion on a motor-driven treadmill at 80% of their respective peak cycling and peak running oxygen (VO2max) uptakes. At the start of exercise, subjects drank 250 ml of a 15 g·100 ml–1 w/v [U-14C]glucose solution and, thereafter, 150 ml of the same solution every 15 min. Despite identical metabolic rates [VO2 3.51 (0.06) vs 3.51 (0.10) 1·min–1; values are mean (SEM) for the cycling and running trials, respectively], exercise times to exhaustion were significantly longer during cycling than running [96 (14) vs 63 (11) min; P < 0.05]. The superior cycling than running endurance was not associated with any differences in either the rate of blood glucose oxidation [3.8 (0.1) vs 3.9 (0.4) mmol· min–1], or the rate of ingested glucose oxidation [2.0 (0.1) vs 1.7 (0.2) mmol· min–1] at the last common time point (40 min) before exhaustion, despite higher blood glucose concentrations at exhaustion during running than cycling [7.0 (0.9) vs 5.8 (0.5) mmol·1–1; P < 0.05]. However, the final rate of total carbohydrate (CHO) oxidation was significantly greater during cycling than running [24.0 (0.8) vs 21.7 (1.4) mmol C6·min–1; P < 0.01]. At exhaustion, the estimated contribution to energy production from muscle glycogen had declined to similar extents in both cycling and running [68 (3) vs 65 (5)%]. These differences between the rates of total CHO oxidation and blood glucose oxidation suggest that the direct and/or indirect (via lactate) oxidation of muscle glycogen was greater in cycling than running. 相似文献
138.
Charles V. Klucka DO Dennis R. Ownby MD Jack Green BS Edward Zoratti MD 《The Journal of allergy and clinical immunology》1995,95(6)
Background: No published studies have compared the effectiveness of several treatments proposed to reduce cat allergenicity. Cat washing studies demonstrating efficacy involved very small sample sizes or infrequent washings. Allerpet-C (Allerpet, Inc., New York, N.Y.), a widely advertised topical spray, and acepromazine, a tranquilizer advocated as efficacious in subsedating doses, have never been scientifically studied. Objective: We compared the effects of cat washing, Allerpet-C spray, and acepromazine with that of no treatment on the shedding of the primary cat allergen, Felis domesticus I by cats. Methods: In a blinded, comparative, controlled study, we measured the amounts of Fel d I shed during an 8-week treatment period with a sample of 24 female mongrel cats randomly assigned to four groups; one group received weekly distilled water washings, one received weekly Allerpet-C spray applications, one received daily oral acepromazine, and one had no treatment (control). Thirty-minute, twice-weekly air samples were collected from each cat with a laminated plastic–acrylic chamber and air sampler. Results: One-sample, two-sided t tests comparing baseline to final-week measurements revealed no significant change in Fel d I within each group (mean change ±SD: washing; 487.6 ± 1896.4 mU per 30 minutes, p = 0.63; Allerpet-C spray, 429.2 ± 871.6 mU per 30 minutes, p = 0.46 acepromazine; −620.6 ± 1031.2, p = 0.52 per 30 minutes). Furthermore, analysis of covariance revealed no significant change in Fel d I levels between groups (p = 0.72). Conclusions: Our data do not show significant reductions in Fel d I shedding as a result of any of these treatments. Therefore we cannot recommend them to patients allergic to cats. (J ALLERGY CLIN IMMUNOL 1995;95:1164-71.) 相似文献
139.
Robert Murray John G. Seifert Dennis E. Eddy Gregory L. Paul George A. Halaby 《European journal of applied physiology》1989,59(1-2):152-158
Summary The purpose of this study was to determine the effect of ingesting fluids of varying carbohydrate content upon sensory response,
physiologic function, and exercise performance during 1.25 h of intermittent cycling in a warm environment (T
db=33.4°C). Twelve subjects (7 male, 5 female) completed four separate exercise sessions; each session consisted of three 20
min bouts of cycling at 65%
, with each bout followed by 5 min rest. A timed cycling task (1200 pedal revolutions) completed each exercise session. Immediately
prior to the first 20 min cycling bout and during each rest period, subjects consumed 2.5 ml·kg BW−1 of water placebo (WP), or solutions of 6%, 8%, or 10% sucrose with electrolytes (20 mmol·l−1 Na+, 3.2 mmol·l−1 K+). Beverages were administered in double blind, counterbalanced order. Mean (±SE) times for the 1200 cycling task differed
significantly: WP=13.62±0.33 min, *6%=13.03±0.24 min, 8%=13.30±0.25 min, 10%=13.57±0.22 min (*=different from WP and 10%,P<0.05). Compared to WP, ingestion of the CHO beverages resulted in higher plasma glucose and insulin concentrations, and higher
RER values during the final 20 min of exercise (P<0.05). Markers of physiologic function and sensory perception changed similarly throughout exercise; no differences were
observed among subjects in response to beverage treatments for changes in plasma concentrations of lactate, sodium, potassium,
for changes in plasma volume, plasma osmolality, rectal temperature, heart rate, oxygen uptake, rating of perceived exertion,
or for indices of gastrointestinal distress, perceived thirst, and overall beverage acceptance. Compared to ingestion of a
water placebo, consumption of beverages containing 6% to 10% sucrose resulted in similar physiologic and sensory response,
while ingestion of the 6% sucrose beverage resulted in significantly improved end-exercise performance following only 60 min
of intermittent cycling exercise. 相似文献
140.
Phospholipase A2 contamination of cobra venom factor preparations. Biologic role in complement-dependent in vivo reactions and inactivation with p-bromophenacyl bromide 总被引:4,自引:3,他引:4 下载免费PDF全文
J O Shaw M F Roberts R J Ulevitch P Henson E A Dennis 《The American journal of pathology》1978,91(3):517-530
Cobra venom factor (CoF), the anticomplementary protein in Naja naja cobra venom, is usually purified by sequential ion exchange and gel filtration chromatography. CoF prepared in this manner contains small but significant quantities of phospholipase A2 activity. This acyl hydrolase activity can be simply and efficiently removed on a large scale by treatment of CoF with p-bromophenacyl bromide (BPB), an irreversible modifier of the histidine residue in the active site of phospholipase A2. BPB treatment does not alter the anticomplementary activity of CoF. In vivo experiments utilizing intratracheal injections of control and BPB-treated CoF, as well as pure phospholipase A2, revealed that contaminating phospholipase A2, and not the anticomplementary protein, was responsible for the observed acute neutrophil-associated lung injury. However, phospholipase A2 had no effect on the hypotensive and thrombocytopenic effects of CoF infected intravenously into rabbits. Depletion of circulating C3-C9 by intraperitoneal injections of CoF was not altered by removal of phospholipase A2 activity with BPB. 相似文献