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101.
Congenital midgut malrotation, a rare anatomic anomaly that can lead to duodenal or small bowel obstruction, rarely is recognized
beyond the first year of life. We report a case of unrecognized congenital midgut malrotation that resulted in midgut volvulus,
causing intestinal obstruction and requiring emergent reoperation after laparoscopic cholecystectomy. This unusual complication,
first reported in 1994, involved a 56-year-old man and resulted in cecal infarction recognized and treated on the second postoperative
day. This second case describes a less acute postoperative course, with multiple bouts of partial bowel obstruction leading
to two readmissions and finally resulting in a reexploration and definitive treatment on the 19th postoperative day.
Received: 16 February 1999/Accepted: 22 March 1999 相似文献
102.
103.
Abrams P Schäfer W Tammela TL Barrett DM Hedlund H Rollema HJ Matos-Ferreira A Nordling J Bruskewitz R Andersen JT Hald T Miller P Kirby R Mustonen S Cannon A Jacobsen CA Gormley GJ Malice MP Bach MA 《The Journal of urology》1999,161(5):1513-1517
PURPOSE: We assess the effect of finasteride, a 5alpha-reductase inhibitor, on objective voiding parameters in men with lower urinary tract symptoms and benign prostatic enlargement on digital rectal examination (known as clinical benign prostatic enlargement) in a double-blind placebo controlled multicenter study using strict standard pressure flow study techniques. MATERIALS AND METHODS: A modification of the Abrams-Griffiths nomogram was used by 1 reader to ensure that all patients met objective criteria for bladder outlet obstruction at baseline. After performing a pressure flow study patients with obstruction were randomized 2:1 to receive 5 mg. finasteride (81) or placebo (40) daily. A second pressure flow study was performed at month 12. At baseline and month 12 free urinary flow studies and transrectal ultrasound were performed, and International Prostate Symptom Score questionnaires were completed. Patients were treated between May 1994 and July 1996. RESULTS: Finasteride caused a significant decrease (-8.1 cm. water) in detrusor pressure at maximum flow (p <0.05 versus placebo p = 0.02), increase (+1.1 ml. per second) in maximum flow rate (p <0.05 versus placebo p = 0.02) and decrease (-22.8%) in prostate volume (p <0.05 versus placebo p <0.001). Men with prostates larger than 40 cc had greater improvement in detrusor pressure at maximum flow (between group difference -14.5 cm. water, 95% confidence interval -26.2 to -2.6, p = 0.02) and maximum flow rate (mean treatment effect +1.6 ml. per second, 95% confidence interval -0.2 to 3.0, p = 0.02) compared to those with prostates 40 cc or less (between group differences not significant). CONCLUSIONS: Finasteride treatment resulted in improvements in urodynamic parameters, which were greater in men with large prostates. 相似文献
104.
The ability to discriminate perfect from imperfect mirror symmetry was examined at the fovea and at eccentricities out to 10 degrees in the nasal visual field. A 2-AFC method of constant stimuli was employed in which a bilaterally symmetric pattern was presented in one interval and a degraded version of this symmetric pattern in the other. The subject's task was to decide which interval contained the perfectly symmetric pattern. Pattern size was varied by changing the viewing distance. Probit analysis revealed the degree of asymmetry corresponding to 75% correct performance. Given sufficient size scaling, perfectly symmetric stimuli can be discriminated from degraded symmetric stimuli in extra-foveal vision. Spatial scaling with an E2 value similar to that for positional acuity was successful in removing the eccentricity dependence for the task. 相似文献
105.
106.
Rationale: Defining the mechanism of tolerance development to hallucinogenic drugs will help to explain their mechanism of action. Objectives: The present study was conducted to determine first, if tolerance develops to the discriminative stimulus (DS) properties
of the hallucinogen, 2,5 dimethoxy-4-iodo-amphetamine (DOI) and second, the mechanism mediating tolerance. Methods: Rats were trained to discriminate 0.75 mg/kg DOI from saline on a concurrent VI-30-min schedule of reinforcement with a
15-min time-out for incorrect responses. To evaluate tolerance development, rats were assigned to one of four groups and treated
with either chronic saline or chronic DOI. Prior to chronic treatment, two groups were tested for choice behavior following
vehicle administration while the remaining two groups were tested following the administration of 0.375 mg/kg DOI. One group
from each pre-test condition was injected with either saline or DOI (1 mg/kg) for 8 days. Twenty-four hours after the last
chronic injection the pre-test treatments were replicated. Using receptor autoradiography, the density of 5-HT2A and 5-HT2C receptors was measured in independent groups of rats that had received identical treatment conditions. Results: Animals receiving chronic DOI showed a 60% decrease in DOI lever responding (from 100% to 40%) when tested on 0.375 mg/kg
DOI, while animals receiving chronic saline showed no change in percent choice (100%) on the DOI lever. Significant changes
in binding were observed in 5-HT2A receptors but not 5-HT2C receptors. The results of tests with antagonists were consistent with the changes in binding. Conclusions: These results suggest that behavioral tolerance to DOI reflects neuroadaptive changes in 5-HT2A receptors.
Received: 17 July 1998 / Final version: 19 January 1999 相似文献
107.
Rationale: Previous research using an amphetamine (AM)-haloperidol (HA) drug- drug discrimination task has shown that predominant responding
on the HA-appropriate lever occurs 24 h after a single or multiple administrations of 10 mg/kg AM. Conversely, rebound responding
on the AM-appropriate lever occurs following single or multiple administrations of 1 mg/kg HA. HA-appropriate responding was
also observed 24 h following a single injection of AM using a three-lever, AM-vehicle-HA discrimination task. However, a single
administration of HA did not produce robust rebound responding on the AM-appropriate lever. The present studies seek to clarify
the discrepancy between responding following HA in the two- and three-choice tasks. Objective: Experiment 1 examined the extent of rebound responding that could be achieved following ten daily administrations of either
10 mg/kg AM or 1 mg/kg HA. Experiment 2 explored potential differences between the two- and three-choice tasks in characterizing
the post-HA cue. Methods: Animals were trained to discriminate 0.35 mg/kg AM, vehicle, and 0.033 mg/kg HA. In experiment 1, animals received ten daily
injections of 10 mg/kg AM, vehicle, or 1 mg/kg HA, and were tested 24 h after the final injection, and again 8, 15, and 22
days post-treatment. In experiment 2, animals were retrained and then treated daily with either vehicle or 1.0 mg/kg HA for
10 days, and then tested 24 h after the final injection, and again 5 and 11 days post-treatment, with either all three levers
or with only the AM- and HA-appropriate levers available. Results: In experiment 1, multiple injections of AM produced robust HA lever responding, which is consistent with results from previous
studies that used the two-choice, AM-HA discrimination task. However, multiple injections of HA did not produce predominant
responding on the AM-appropriate lever. In experiment 2, animals treated with either vehicle or HA responded predominantly
on the vehicle-appropriate lever when tested with all three levers present. When tested with the vehicle lever removed, however,
animals treated with vehicle responded predominantly on the HA-appropriate lever, whereas those treated with HA responded
predominantly on the AM-appropriate lever. Conclusions: These results suggest that the two-choice and three-choice task used here differ in how the post-HA withdrawal cue is characterized.
This finding emphasizes the importance of knowing the relative locations of the agonist-, vehicle-, and antagonist-produced
cues on the interoceptive stimulus continuum established by discrimination training.
Received: 3 December 1997/Final version: 16 November 1998 相似文献
108.
The serotonin3 (5-HT3) receptor plays an important role in the aminoprivic feeding model. Other neurochemical systems, including cholecystokinin (CCK) and dopamine (DA), are known to affect food intake. We pretreated rats systemically with tropisetron, a 5-HT3 receptor antagonist, alone and combined with antagonists of DA1 and DA2 receptors, and measured intake of an amino acid-imbalanced diet (IMB). As expected, tropisetron significantly increased intake of IMB. SCH-23390, a DA1 antagonist, increased IMB anorexia. When combined with tropisetron, DA2 antagonism with eticlopride reduced short-term intake of both the basal diet (BAS) and IMB. In the IMB model, specificity of 5-HT3-DA2 interactions, and of 5-HT3-CCK(A) interactions from previous studies, prompted investigation of CCK(A)-DA2 interactions; there appeared to be none. SKF-38393, a DA1 agonist, combined with the CCK(A) receptor antagonist, devazepide, increased BAS and tended to increase IMB intake. Thus, CCK(A)-DA1 interactions were not specific for IMB. These data suggest that DA1 receptor activity opposes IMB anorexia, possibly via an interaction with the 5-HT3 receptor. 相似文献
109.
Barrett JS Hochadel TJ Morales RJ Rohatagi S DeWitt KE Watson SK DiSanto AR 《American journal of therapeutics》1996,3(10):688-698
This open-label, two-phase cross-over study compared the safety and pharmacokinetics of transdermally administered selegiline and orally administered selegiline hydrochloride in elderly men and women (n = 6/gender). Single oral doses of 10 mg selegiline hydrochloride and single 1/2 and 1 selegiline transdermal system (STS) (delivering similar3.4 and 6.3 mg over 24 h) administered topically were safe and well tolerated in all subjects. Plasma concentrations of selegiline (SEL) and its N-desmethylselegiline (DMS), L-amphetamine (AMP), and L-methamphetamine (MET) metabolites were measured using an HPLC/MS/MS method with lower quantitation limits of 10, 50, 200, and 200 pg/mL, respectively. No significant gender-related differences were observed following single 10-mg oral doses of selegiline hydrochloride or single 24-h applications of 1/2 and 1 STS to elderly males and females. The low level of dermal irritation as assessed by erythema and edema rating scales suggests that the STS was similar to Band-Aid (Johnson & Johnson, Skillman, NJ) controls. The transdermal administration of SEL bypasses the first-pass metabolism, that is significant after oral administration (first-pass extraction >90%). Peak plasma levels of 1.19, 23.22, 4.78, and 14.08 ng/mL were observed for SEL, DMS, AMP, and MET after a single 10-mg oral dose to the elderly. By contrast, peak plasma levels of 2.10, 0.85, 1.06, and 2.71 ng/mL were observed for SEL, DMS, AMP, and MET after a single 24-h application of 1 STS. Comparison of dose-corrected areas under the curve (AUCs) (made under the assumption of linear pharmacokinetics) indicate the SEL exposure after transdermal application was more than 50-fold greater than that obtained orally. This increase in systemic SEL exposure at the expense of metabolite formation that is reduced to <70% of that obtained orally for N-DMS, L-AMP, and L-MET is hypothesized to be of therapeutic value in patients with a variety of neurodegenerative and psychiatric disorders. 相似文献
110.
Randall ME Barrett RJ Spirtos NM Chalas E Homesley HD Lentz SL Hanna M 《International journal of radiation oncology, biology, physics》1996,34(1):139-147
PURPOSE: To determine outcomes and treatment toxicities in patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma treated with three courses of cisplatin-cyclophosphamide, surgical reassessment (SRA), and hyperfractionated whole abdominal irradiation (WAI). METHODS AND MATERIALS: Forty-two eligible patients entered this prospective Phase II study conducted by the Gynecologic Oncology Group (GOG). Disease characteristics were as follows: age range, 32-76 years (median 58); Stage IIIA (n = 1, 2%), IIIB (n = 2, 5%), IIIC (n = 39, 93%); histology-serous papillary (n = 21, 50%); other (n = 21, 50%); Grade 1 (n = 1, 2%); 2 (n = 14, 33%); 3 (n = 27, 54%); residual disease after initial surgery (present: n = 23, 55%; absent: n = 19, 45%). Five patients progressed while on chemotherapy, could not be effectively cytoreduced, and were not eligible for WAI. Of the remaining 37 patients, 35 received WAI. Surgical reassessment was not performed in five patients. RESULTS: Of 37 patients with known SRA status after chemotherapy, 21 (57%) were grossly positive, 4 (11%) were microscopically positive, and 12 (32%) were negative. Based on measurements recorded following initial laparotomy and surgical reassessment, progression during chemotherapy was noted in 40%, stage disease in 37%, and objective response in 23%. Toxicity during hyperfractionated WAI was limited and reversible. No patient beginning WAI failed to complete or required a significant treatment break. Following WAI, six patients underwent laparotomies for abdominal symptoms; five had recurrent disease. Five additional patients were managed conservatively for small bowel obstruction (SBO) or malabsorption, of whom three subsequently developed recurrence. Twenty-two patients having pelvic boosts were significantly more likely to require management for gastrointestinal morbidity (p = 0.0021). Considering all eligible patients, median disease-free and overall survivals were 18.5 and 39 months, respectively. Considering patients completing chemotherapy and WAI, median disease-free and overall survivals were 24 and 46 months, respectively. CONCLUSIONS: (a) Disease progression occurred within three cycles of cisplatin and cyclophosphamide chemotherapy in 40% of patients with optimal (< or = 1 cm residual) Stage III ovarian carcinoma. (b) Following limited chemotherapy, hyper-fractionated WAI was acutely well tolerated. (c) Late radiation-related toxicity was observed in only three patients (8.6%) in the absence of recurrent disease. Late gastrointestinal morbidity was significantly associated with the administration of a pelvic radiotherapy (RT) boost. (d) Short duration chemotherapy followed by SRA and hyperfractionated WAI without a pelvic boost is a promising management option for patients with optimal Stage III ovarian cancer. A Phase III trial will be necessary to determine how this treatment strategy compares with chemotherapy or RT alone in this patient population. 相似文献