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121.
BACKGROUND: Management of the gallbladder in patients undergoing laparoscopic Roux-en-Y gastric bypass (LRYGBP) is controversial. We reviewed our experience in patients undergoing LRYGBP without routine gallbladder screening. METHODS: The data of 644 patients who underwent LRYGBP at our institution were analyzed. Preoperative ultrasonography was routinely obtained early in our series and selectively thereafter in patients with suspected symptomatic biliary disease. Cholecystectomy at LRYGBP was performed in symptomatic patients with positive ultrasound findings. Postoperatively, patients with intact gallbladders were prescribed ursodiol for 6 months. RESULTS: Of the 644 patients, 155 (24%) had history of cholecystectomy. A total of 104 patients underwent preoperative ultrasonography. Of the 104 patients, 20 had positive ultrasound findings and symptoms consistent with biliary disease and underwent concomitant cholecystectomy. Twelve patients had positive ultrasound findings and no biliary symptoms and did not undergo cholecystectomy. At a mean follow-up of 26.4 months, only 1 (8.3%) of the 12 patients had required cholecystectomy. Of the 104 patients, 72 had negative ultrasound findings. At a mean follow-up of 21.2 months, 5 of them (6.9%) had required cholecystectomy. The remaining 385 patients did not undergo any gallbladder screening. At a mean follow-up of 14 months, 32 (8.3%) of 385 patients had required cholecystectomy. Compliance with ursodiol for >4 months was only 39%. A time-to-event analysis did not reveal a significant difference in the cholecystectomy rate between asymptomatic patients with preoperative gallbladder screening and patients with no screening. CONCLUSION: Omission of gallbladder screening in asymptomatic patients undergoing LRYGBP is a reasonable approach that spares the patient a potentially unnecessary procedure with all its associated risks.  相似文献   
122.
Athletes have a high prevalence (11-50%) of exercise-induced asthma, which may be caused by the hyperventilation accompanying repetitive bouts of strenuous exercise. We hypothesized that recreational exercisers would display a similar trend. Eucapnic voluntary hyperventilation (EVH) bronchoprovocation (breathing 21% O2, 5% CO2, and 74% N2 at 60% of MVV for 5 minutes) was performed to determine the prevalence of airways hyperresponsiveness (AHR) in adults (n=212, 146 males, mean +/- standard deviation, age 32 +/- 10 years) who exercised regularly (10 +/- 10 years, 31 +/- 28% of their lives): none had a previous diagnosis of asthma. AHR was defined by at least a 10%, 20%, or 25% decline in FEV1, FEF(25-75), or PEFR, respectively, by spirometry at 1, 5, 10, and 15 minutes post-EVH. Forty-one of 212 (19%) tested positive for AHR: 20 of 41 (49%) were positive by FEV1, 28 of 41 (68%) by FEF(25-75), and 27 of 41 (66%) by PEFR. Comparing responders with nonresponders: pre-EVH lung function was equivalent, except for FEV1, which was reduced (p<0.05) in responders (96 +/- 13 vs. 102 +/- 12% predicted). Mean maximal negative deflections for responders were: for FEV1, -17 +/- 7%; FEF(25-75), -31 +/- 10%; PEFR, -38 +/- 11%. Ranges of decline for responders were: FEV1, -10 to -33%; FEF(25-75), -20 to -59%; PEFR, -25- to -70%. We conclude that in these regular exercisers, the prevalence of AHR is high and comparable with some athletic populations.  相似文献   
123.
Cells of the immune system are shown to produce peptide hormones whose production was once thought to be restricted to neuroendocrine tissue. Interestingly, in some cases, very specific stimuli elicit the production of one species of neuropeptide hormone. In other instances, it appears that some peptide hormones are constitutively produced. In either situation, the various immunocyte-derived hormones have biological activity in endocrinological assays. In the present report, a review of the various neuroendocrine hormones produced by cells of the immune system is discussed.  相似文献   
124.
A retrospective study was performed to compare intravenous lorazepam and intravenous diazepam in the treatment of status epilepticus. Forty-five episodes of status epilepticus in children between the ages of 2 weeks and 18 years were reviewed. Lorazepam and diazepam proved similar in efficacy of seizure control and incidence of adverse effects. The dose of lorazepam required to control status epilepticus ranged from 0.03 to 0.22 mg/kg with a mean of 0.11 mg/kg (S.D. = 0.05 mg/kg). Among children treated with lorazepam, only children younger than 2 years of age had respiratory depression which required intubation.  相似文献   
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127.
A feedforward network is used to recognize short, digitized, isolated utterances. A high, multispeaker recognition rate is achieved with a small vocabulary with a single training utterance. This approach makes use of the pattern recognition property of the network architecture to classify different temporal patterns in the multidimensional feature space. The network recognizes the utterances without the need of segmentation, phoneme identification, or time alignment. We train the network with four words spoken by one single speaker. The network is then able to recognize 20 tokens spoken by 5 other speakers. We repeat the above training and testing procedure using a different speaker's utterances for training each time. The overall accuracy is 97.5%. We compare this approach to the traditional dynamic programming (DP) approach, and find that DP with slope constraints of 0 and 1 achieve 98.5% and 85% accuracies respectively. Finally we validate out statistics by training and testing the network of a four-word subset of the Texas Instruments (Tl) isolated word database. The accuracy with this vocabulary exceeds 96%. By doubling the size of the training set, the accuracy is raised to 98%. Using a suitable threshold, we are able to raise the accuracy of one network from 87% to 98.5%. Thresholding applied to all networks would then raise the overall accuracy to well over 99%.

This technique is especially promising because of the low overhead and computational requirements, which make it suitable for a low cost, portable, command recognition type of application.  相似文献   

128.
Ferroquine (SSR97193) has been shown to be a promising antimalarial, both on laboratory clones and on field isolates. So far, no resistance was documented in Plasmodium falciparum. In the present work, the metabolic pathway of ferroquine, based on experiments using animal and human hepatic models, is proposed. Ferroquine is metabolized mainly via an oxidative pathway into the major metabolite mono-N-demethyl ferroquine and then into di-N,N-demethyl ferroquine. Some other minor metabolic pathways were also identified. Cytochrome P450 isoforms 2C9, 2C19, and 3A4 and, possibly in some patients, isoform 2D6, are mainly involved in ferroquine oxidation. The metabolites were synthesized and tested against the 3D7 (chloroquine-sensitive) and W2 (chloroquine-resistant) P. falciparum strains. According to the results, the activity of the two main metabolites decreased compared with that of ferroquine; however, the activity of the mono-N-demethyl derivative is significantly higher than that of chloroquine on both strains, and the di-N-demethyl derivative remains more active than chloroquine on the chloroquine-resistant strain. These results further support the potential use of ferroquine against human malaria.  相似文献   
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