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991.
992.
We assessed differences in food reinforced behavior between obese and lean Zucker rats with a progressive ratio schedule
3 (PR3) in which a subject emitted three additional lever-presses each time a reinforcer was delivered. The number of responses
required for a reinforcer eventually exceeded its value, termed the ”break point”, a sensitive measure of food motivated behavior.
Break points were higher in obese rats than lean controls for grain pellets (27.5 versus 9.5, P=0.01) but not for sweet pellets (51.6 versus 38.5, P=0.31). We determined if naloxone (0.01–3.0 mg/kg, SC), which reduces free food intake in obese Zucker rats, affects food
motivated behavior in obese Zuckers and lean controls. Naloxone reduced break points in both obese and lean rats to a similar
extent when working for either grain pellets or sweet pellets. Under free-access feeding conditions, naloxone again decreased
pellet intake similarly in the obese and lean Zucker rats. Naloxone appeared to decrease free-access pellet consumption to
a greater extent than break point in both groups. These results show that (1) obese rats exhibit higher levels of performance
for food than lean rats only when working for the less valued grain pellet, (2) naloxone reduces both break points and free-access
pellet consumption independent of genotype, and (3) naloxone appears to decrease food more effectively in rats given free
access to food than in rats working for food.
Received: 4 April 1998 / Final version: 19 August 1998 相似文献
993.
Rationale: Altered hormonal stress responsiveness has been implicated in psychostimulant responsivity, and early handling represents
a mild environmental manipulation which alters the hormonal profile following stress exposure. Objective: The present experiments examined whether early handling in rats would alter locomotor effects of amphetamine, as well as
cross-sensitization of locomotor responsiveness after chronic stress. Conditioned place preference (CPP) for amphetamine was
also measured. Methods: Handling consisted of daily 15-min isolation periods from days 1–12 postnatally. Novelty- and amphetamine (0, 1.5 mg/kg)-induced
locomotion were examined using circular corridors in adult rats that were either restrained repeatedly over 8 days or not
disturbed prior to testing. The effects of handling on amphetamine (0, 1, 2, 5 mg/kg) conditioned place preference (CPP) were
also examined following 3 days of drug-compartment pairings. Results: Early handling produced a more rapid post-stress recovery in corticosterone levels. Handled animals also exhibited a significant
attenuation in amphetamine-induced CPP compared to non-handled controls. Locomotor responsiveness to novelty and amphetamine
was not altered by early handling. Although no cross-sensitization was observed, evidence for stress sensitization was seen,
but was unaffected by early handling. Conclusions: Handled animals showed an attenuated CPP for amphetamine, data suggesting that sensitivity to the reward value of drugs
of abuse in adulthood may be susceptible to relatively minor environmental manipulations early in life. This effect of handling
on CPP does not seem to reflect differences in locomotor sensitivity to amphetamine.
Received: 5 August 1998 / Final version: 2 November 1998 相似文献
994.
Rationale: Facial expressions appear to be processed by at least partially separable neuro-cognitive systems. Given this functional
specialisation of expression processing, it is plausible that these neurocognitive systems may also be dissociable pharmacologically.
Objective: The present study therefore compared the effects of diazepam (15 mg) with placebo upon the ability to recognise emotional
expressions. Methods: A double blind, independent group design was used to compare the effects of diazepam and matched placebo in32 healthy volunteers.
Participants were presented morphed facial expression stimuli following a paradigm developed for use with patients with brain
damage and asked to name one of the six basic emotions (sadness, happiness, anger, disgust, fear and surprise). Results: Diazepam selectively impaired subjects’ ability to recognise angry expressions but did not affect recognition of any other
emotional expression. Conclusions: The findings are interpreted as providing further support for the suggestion that there are dissociable systems responsible
for processing emotional expressions. It is suggested that these findings may have implications for understanding paradoxical
aggression sometimes elicited by benzodiazepines.
Received: 27 May 1999 / Accepted: 7 July 1999 相似文献
995.
Howard L. Kaufman M.D. Dr. Andrew H. Fischer M.D. Mitchell Carroll M.D. Dr. James M. Becker M.D. 《Diseases of the colon and rectum》1996,39(6):705-710
Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with a variety of gastrointestinal side effects. Effects on the large intestine have been reported with increasing frequency. Recognition of NSAID-induced colonic lesions has been confounded by variable clinical presentations, variable pathologic findings, and unfamiliarity of this entity among clinicians. We have recently seen three cases of NSAID-induced cecal ulcerations in patients undergoing right colectomy. A correct preoperative diagnosis was not made in our patients, one of whom presented with an acute abdomen and two in whom there was an inability to rule out carcinoma. The gross, radiographic, and histologic findings in each case consisted of a characteristic transverse ulceration with thin diaphragm-like scarring. NSAID-induced cecal ulcers can have a variety of presentations to the general surgeon, are likely to be misdiagnosed preoperatively, but may be recognized based on characteristic gross features evident by radiography and colonoscopy, along with a careful history. Review of recent literature suggests that laparotomy can be avoided when diagnosis is considered, but operation is indicated for complications, such as hemorrhage, obstruction, or perforation, and when carcinoma cannot be adequately excluded. 相似文献
996.
Morris E. FranklinJr. Daniel Rosenthal Daniel Abrego-Medina James P. Dorman Jeffrey L. Glass Richard Norem Antonio Diaz 《Diseases of the colon and rectum》1996,39(10):S35-S46
Laparoscopy for colonic diseases began in 1990 and has established a role in benign disease. Early observations and experiences demonstrated feasibility of laparoscopic surgery for a variety of colonic disease processes, but the applicability to colonic carcinoma was unclear. METHODS: In 1990, we began a comparative study of open (OCR)vs.laparoscopic (LCR) approach to colon cancer. The study progressed 65 months, with 224 patients in OCR group and 191 patients in LCR group. Parameters studied are stage, location, length of specimen, number of lymph nodes resected, margins, postoperative course, wound complications, recurrence rates, and immediate and long-term survival. OCR were standardized by one group, and LCR were standardized by a second group. All patients undergoing LCR were given freedom to choose either OCR or LCR, and informed consent was obtained. RESULTS: Equal or greater lymph node retrieval, resections, and distal margins were evident with LCR. Benefits with LCR were shown with shorter hospitalization (5.7vs.9.7 days), less blood loss, less wound problems (1vs.14), and quicker return of bowel function. Survival, recurrence, and death rates were essentially the same. There were no trocar implants in the LCR group. CONCLUSION: After five years, this study shows that laparoscopy does no harm to the patient, offers comparable oncologic resections, and seems to be patient-friendly, with less pain, quicker return of bowel functions, shortened hospitalization, and quicker return to full activity. 相似文献
997.
Pieter H. Van der Graaf Nigel P. Shankley James W. Black 《Naunyn-Schmiedeberg's archives of pharmacology》1996,354(3):389-392
We have studied the effects of idazoxan in rat aorta and small mesenteric artery. In the aorta, idazoxan behaved as a partial agonist (pKA=6.30). Prazosin produced rightward shift (pA2=9.88) and steepening of the idazoxan curve. In contrast, idazoxan had no effect of basal tension in the mesenteric artery, but shifted the noradrenaline curve to the right in a parallel manner (pA2=6.12). The selective al-adrenoceptor agonist, indanidine, also behaved as a partial agonist in the aorta and produced no significant contractions of the small mesenteric artery. Since idazoxan and indanidine have been reported to raise blood pressure in the pithed rat via an action at vascular 1-adrenoceptors, these results call into question the reliability of the small mesenteric artery assay as a predictor for 1-adrenoceptor-mediated pressor activity in vivo. 相似文献
998.
James N. Ingle MD Carl G. Kardinal Vera J. Suman James E. Krook Alan K. Hatfield 《Investigational new drugs》1996,14(2):235-237
Summary Octreotide is a synthetic somatostatin analogue which has shown inhibitory activity against human breast cancer cells in culture. Ten patients with metastatic breast cancer and no prior hormonal therapy exposure received octreotide at 150 g subcutaneously thrice daily. No objective responses were observed and the median time to treatment failure was short at 57 days. 相似文献
999.
Clinical Guidelines Panel on Erectile Dysfunction: Summary Report on the Treatment of Organic Erectile Dysfunction 总被引:4,自引:0,他引:4
Drogo K. Montague James H. Barada Arnold M. Belker Laurence A. Levine Perry W. Nadig Claus G. Roehrborn Ira D. Sharlip Alan H. Bennett 《The Journal of urology》1996,156(6):2007-2011
Purpose
The American Urological Association convened the Clinical Guidelines Panel on Erectile Dysfunction to analyze the literature regarding available methods for treating organic erectile dysfunction and to make practice recommendations based on the treatment outcomes data.Materials and Methods
The panel searched the MEDLINE data base for all articles from 1979 through 1994 on treatment of organic erectile dysfunction and meta-analyzed outcomes data for oral drug therapy (yohimbine), vacuum constriction devices, vasoactive drug injection therapy, penile prosthesis implantation and venous and arterial surgery.Results
Estimated probabilities of desirable outcomes are relatively high for vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis therapy. However, patients must be aware of potential complications. The outcomes data for yohimbine clearly indicate a therapy with marginal efficacy. For venous and arterial surgery, based on reported outcomes, chances of success do not appear high enough to justify routine use of such surgery.Conclusions
For the standard patient, defined as a man with acquired organic erectile dysfunction and no evidence of hypogonadism or hyperprolactinemia, the panel recommends 3 treatment alternatives: vacuum constriction devices, vasoactive drug injection therapy and penile prosthesis implantation. Based on the data to date, yohimbine does not appear to be effective for organic erectile dysfunction and, thus, it should not be recommended as treatment for the standard patient. Venous surgery and arterial surgery in men with arteriolosclerotic disease are considered investigational and should be performed only in a research setting with long-term followup available. 相似文献1000.
Nicholas A. Kimberley Susan M. Kirkpatrick James M. Watters 《Canadian journal of surgery》1996,39(4):312-316