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11.
Hagan MM Wauford PK Chandler PC Jarrett LA Rybak RJ Blackburn K 《Physiology & behavior》2002,77(1):45-54
Dieting and stress are important in the etiology and maintenance of eating disorders, and dieting strongly predicts stress-induced overeating in humans. We hypothesized that caloric restriction and stress interact in a unique manner to promote binge eating. To test this hypothesis, a group of young female rats were cycled through a restriction period (4 days of 66% of control food intake) followed by 6 days of free feeding prior to being stressed by acute foot shock. After three of these cycles, the food intake of rats exposed only to restriction (R), or only to stress (S), did not differ from controls. However, R+S rats that were restricted and refed, despite normal body weight and food intake after free feeding, engaged in a powerful bout of hyperphagia when stressed (Experiment 1). The R + S effect was replicated in an older group of rats (Experiment 2). The hyperphagia was characteristically binge-like, it constituted a 40% selective increase in highly palatable (HP) food (P < .001) over a discrete period of time (within 24 h post-stress), and reflected feeding for reward (higher HP:chow ratio) over metabolic need as occurred after restriction (higher chow:HP ratio). Subsequent experiments revealed that binge eating did not occur if only chow was available (Experiment 3) or if restriction-refeeding (R-R) did not proximally precede stress (Experiment 4). Experiment 5 revealed that a history of R-R cycles followed by only one stress episode was sufficient to increase intake to 53% above controls as early as 2 h after stress (P < .001). This animal model of binge eating should facilitate investigations into the neurochemical changes induced by dieting and environmental stress to produce disordered eating and provide a preclinical tool to test preventive strategies and treatments more relevant to bulimia nervosa, multiple cases of binge eating disorder (BED) and binge-purge type anorexia nervosa. 相似文献
12.
The ability of the anticholinergic agent, ipratropium bromide, Atrovent, (40 mcg from a metered dose inhaler) to prevent bronchoconstriction produced by four different provocation tests was compared with placebo in 12 asthmatic patients. The provocation tests used were hyperventilation and inhalations of histamine, methacholine and an allergen to which the subject was known to be sensitive. The order in which each patient received the tests was determined according to a Latin-square design and remained the same on both test days. Pretreatment with ipratropium bromide and placebo was allocated randomly and administered in double-blind fashion. Ipratropium bromide provided significant protection at the 5% level against all four types of challenge. The average number of breaths required to produce a fall of at least 20% in FEV1 (forced expiratory volume in one second) was doubled for both histamine and allergen and increased by a factor of six for methacholine. The fall in FEV1 induced by hyperventilation was approximately halved. No side effects were noted with ipratropium bromide. 相似文献
13.
Lomber SG Payne BR Hilgetag CC Rushmore J 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,142(4):463-474
A contralateral hemineglect of the visual field can be induced by unilateral cooling deactivation of posterior middle suprasylvian (pMS) sulcal cortex of the posterior parietal region, and this neglect can be reversed by additional cooling deactivation of pMS cortex in the opposite hemisphere. The purpose of the present study was to test whether an enduring hemianopia induced by removal of all contiguous visual cortical areas of one hemisphere could be reversed by local cooling of pMS cortex in the opposite hemisphere. Two cats sustained large unilateral ablations of the contiguous visual areas, and cooling loops were placed in the pMS sulcus, and in contact with adjacent area 7 or posterior ectosylvian (PE) cortex of the opposite hemisphere. In both instances cooling of pMS cortex, but neither area 7 nor PE, restored a virtually normal level of orienting performance to stimuli presented anywhere in the previously hemianopic field. The reversal was highly sensitive to the extent of cooling deactivation. In a third cat, cooling deactivation of the superficial layers of the contralateral superior colliculus also restored orienting performance to a cortical ablation-induced hemianopia. This reversal was graded from center-to-periphery in a temperature-dependent manner. Neither the cortical ablation nor any of the cooling deactivations had any impact on an auditory detection and orienting task. The deactivations were localized and confirmed by reduced uptake of radiolabeled 2-deoxyglucose to be limited to the immediate vicinity of each cooling loop. The results are discussed in terms of excitation and disinhibition of visual circuits. 相似文献
14.
Feline leukaemia virus: protective immunity is mediated by virus-specific cytotoxic T lymphocytes 总被引:3,自引:0,他引:3 下载免费PDF全文
Feline leukaemia virus (FeLV) nucleic acid vaccination of domestic cats affords protection against viraemia and the development of latency without inducing antiviral antibodies.1 To determine the contribution of cell-mediated immunity to the control of virus replication and clearance from the host, FeLV-specific cytotoxic T lymphocyte (CTL) responses were compared in vaccine-protected, transiently viraemic, and persistently viraemic cats. Vaccinal immunity was associated with the detection of higher levels of virus-specific effector CTL in the peripheral blood and lymphoid organs to FeLV Gag/Pro and Env antigens than those observed in unvaccinated control, persistently viraemic cats (P<0.001). Likewise, higher levels of virus-specific CTLs were also observed in transiently viraemic cats which recovered following exposure to FeLV. In cats that controlled their infection, recognition of Gag/Pro antigens was significantly higher than the recognition of Env antigens. This is the first report highlighting the very significant role that virus-specific CTL have in determining the outcome of FeLV infection in either vaccinated cats or cats recovering naturally from FeLV exposure. 相似文献
15.
To study the effects of improved control of blood glucose on markers of renal glomerular and tubular function, we initially determined, by radioimmunoassay technics, urinary excretion rates of albumin and beta2 microglobulin in 17 nondiabetic subjects and in 43 insulin-dependent, clinically nonproteinuric diabetic patients. Duration of diabetes ranged from six months to 39 years, and the patients were studied while receiving conventional therapy. Mean urinary albumin excretion was significantly elevated in the diabetics, but beta2-microglobulin excretion rates were not different from those of the controls, suggesting that the increased albumin excretion was due to increased transglomerular loss of albumin. Seven patients with long-term diabetes (duration of six to 33 years), selected because of elevated albumin excretion, were studied before and during a continuous, subcutaneous insulin infusion for a period of one to three days. Urinary albumin excretion was significantly reduced during the insulin infusion, but mean beta2-microglobulin excretion did not change. Strict control of blood glucose, even in the short term, may reverse a functional renal abnormality in long-duration, insulin-dependent diabetes. 相似文献
16.
Hew WS Carey FA Kernohan NM Heppleston AD Jackson R Jarrett RF 《Journal of clinical pathology》2002,55(1):61-63
Lymphoma of the salivary gland accounts for 5% of cases of extranodal lymphoma and 10% of malignant salivary gland tumours. Most primary salivary gland lymphomas are B marginal zone lymphomas arising on a background of sialadenitis associated with autoimmune disorders such as Sjorgen's syndrome. Primary T cell lymphoma of the salivary gland is rare. This report describes a case of primary T cell lymphoma arising in the parotid gland of an elderly white man, which was notable for its striking resemblance to a B cell extranodal marginal zone lymphoma. Immunohistochemistry and gene rearrangement studies confirmed the clonal T cell nature of the tumour. There was no molecular evidence of Epstein-Barr virus (EBV) infection of neoplastic or surroundings cells. Only 14 cases of primary T cell lymphoma of the salivary glands have been recorded in the literature, most being from the Orient and having extremely variable prognosis. Those with a T/natural killer cell phenotype are associated with EBV infection. This case highlights the fact that T cell lymphoma in the salivary gland can mimic closely the morphological features of B cell extranodal marginal zone lymphoma. 相似文献
17.
A A Bernard J N O'Hara S Bazin B Humby R Jarrett N S Dwyer 《Journal of pediatric orthopedics》1987,7(3):277-282
A screening programme for congenital dislocation of the hip in which physiotherapists examine all neonates is described, together with the results over a 7-year period. All easily reducible dislocated and dislocatable hips are splinted within 2-5 days of birth. Subluxable or "slidey" hips are identified and followed up but not splinted. Risk groups are also identified and followed up. There was a progressive decrease in the number of late diagnosed cases, a result suggesting that even late-presenting acetabular dysplasia can be eliminated by neonatal screening. 相似文献
18.
The intention of a surveillance program to monitor prostate cancer patients is to detect recurrence of disease as soon as possible and institute therapy at the time of recurrence in order to improve the chance of cure or extend survival. We analyzed the cost of four surveillance programs for prostate cancer. As PSA levels are more sensitive than the bone scan, prostatic acid phosphatase and alkaline phosphatase, a surveillance program which utilizes these latter tests provides no additional clinically useful information beyond a PSA level and is costly. Adopting a strategy of eliminating these tests from a surveillance program would reduce national annual expense by approximately $1.5 billion in the year 2000. 相似文献
19.
To study the role of nutritional factors in the genesis of diabetes, estimations of blood sugar concentration, food intake, and adiposity (as body mass index; BMI) were carried out on three normal population samples--namely, 961 employees of Beecham Ltd, 1005 employees of the Greater London Council, and 1488 middle-aged male civil servants (Whitehall study). Blood sugar concentrations and indices of glucose tolerance correlated positively with the degree of adiposity but tended to be negatively correlated with total food energy intake and its component nutrients (total carbohydrate, sucrose, and fat). This inverse trend was largely accounted for by highly significant inverse correlations between food energy intake and adiposity, a relation found in both sexes and in all three population samples and which extended across the whole range of nutrient intake and BMI. These findings suggest that greater degrees of adiposity are associated with lower than average food energy intakes and hence lower total energy expenditures. The association of increased adiposity with low food energy consumption may indicate an underlying "low energy throughput" state, and it may be the mechanisms of this, as well as the obesity, that are responsible for disease. 相似文献
20.
Chan DY Jarrett TW 《Journal of endourology / Endourological Society》2000,14(3):269-72; discussion 272-3
Standard percutaneous nephrolithotomy is highly effective for the removal of renal calculi. However, significant morbidity has been associated with this procedure. Consequently, many urologists inappropriately defer to a less effective procedure to reduce patient morbidity. This practice may increase the total number of procedures needed for treatment and result in a substantial increase in health care costs. Mini-percutaneous nephrolithotomy using a 13F ureteroscopy sheath is described to reduce the morbidity associated with standard percutaneous nephrolithotomy while maintaining its efficiency and effectiveness for stone removal. The indications and technique for mini-percutaneous nephrolithotomy and our results are summarized. 相似文献