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A high-pressure liquid chromatographic procedure for the simultaneous determination of niacin and niacinamide in multivitamin preparations was developed and evaluated. Reversed-phase liquid chromatography with dioctyl sodium sulfosuccinate in the mobile phase is utilized for the analysis. The accuracy and precision of the procedure were compared with those of the currently official procedure.  相似文献   
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Increased numbers of peritoneal macrophages have been repeatedly associated with infertility. Because the factors contributing to this intraperitoneal exudate are unknown, this study was carried out to determine which anatomic or endocrinologic abnormalities in infertile women might be associated with an increase in leukocyte numbers. The peritoneal fluid from 103 women was analyzed. Nonparametric data analysis demonstrated significantly greater cell counts in infertile women with endometriosis, compared with other infertile women (P less than 0.01) or fertile control subjects (P less than 0.005). Multiple regression analysis was then used to determine the relationship of individual variables to cell number without the influence of confounding factors. These data demonstrate that the best correlation with elevated macrophage number is in women who have infertility and no mechanical fertility factors (of which mild endometriosis is a subgroup). Thus, an increase in peritoneal macrophage number is not restricted to women with endometriosis but, rather, is seen in a subset of infertile women generally without mechanical or endocrinologic infertility factors.  相似文献   
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A pseudocyst developed in a child following acute pancreatitis and spontaneously drained into the common bile duct, a rare occurrence previously described only in adults. The imaging findings are similar to those of a choledochal cyst; serial sonograms enabled diagnosis by documenting evolution of the lesion and should be of value in demonstrating resolution.  相似文献   
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A 23-year-old male originally presented in a chiropractor's office for low back pain and leg pain. The case is followed through using conservative procedures without lasting relief. Procedures and special studies are related for determining referral for chemonucleolysis which satisfactorily relieved the condition. Need for proper protocol in problem low back cases is discussed.  相似文献   
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Common complaints among shift workers are sleep disruptions and increased sleepiness while working, which may contribute to shift workers being more susceptible to diminished performance and work-related accidents. The purpose of this double-blind, within-participant study was to examine the effects of the alerting agent modafinil on cognitive/psychomotor performance, mood, and measures of sleep during simulated shift work. In all, 11 participants completed this 23-day residential laboratory study. They received a single oral modafinil dose (0, 200, 400 mg) 1 h after waking for three consecutive days under two shift conditions: day shift and night shift. Shifts alternated three times during the study, and shift conditions were separated by an 'off' day. When participants received placebo, cognitive performance and subjective ratings of mood were disrupted during the night shift, relative to the day shift. Objective and subjective measures of sleep were also disrupted, but to a lesser extent. Modafinil reversed disruptions in cognitive performance and mood during the night shift. While modafinil produced few effects on sleep measures during the night shift, the largest dose produced several sleep alterations during the day shift. These data demonstrate that abrupt shift changes produced cognitive performance impairments and mood disruptions during night shift work. Therapeutic doses of modafinil attenuated night-shift-associated disruptions, but the larger dose produced some sleep impairments when administered during day-shift work.  相似文献   
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Background/Purpose: Controversy surrounds the justification of a second course of extracorporeal membrane oxygenation (ECMO) for patients that deteriorate after initial decannulation. The authors' experience with a small number of patients requiring recannulation led them to investigate the results of a second ECMO course from all institutions that report to the ELSO registry. Methods: The ELSO neonatal registry for patients that underwent multiple ECMO courses was reviewed and mortality and complication rates between first and second courses were compared. Complications were classified according to the following ELSO registry defined categories: hemorrhagic, mechanical, metabolic, infectious, renal, pulmonary, neurologic, and cardiac. Results: Of the 16,450 patients in the ELSO neonatal registry in January 2000, 205 patients (1.25%) have required multiple ECMO courses. There have been 201 patients (1.22%) who have needed 2 courses of ECMO and 4 patients (0.024%) have undergone 3 ECMO runs. A total of 557 complications occurred during the first ECMO course in these 205 patients, and 672 complications developed during the second course. This represents an increase in the complication rate by 20.6% during the second ECMO course. Although mechanical complications were the most common, there was no change in the incidence between first and second courses. However, the frequency of complications increased in all other classifications during the second course when compared with the first. The largest increases occurred with neurologic and infectious complications (134% and 79% increases, respectively). Renal and metabolic complications also were markedly elevated (35% and 24%, respectively). Seventy-six of 201 (38%) patients who required 2 courses of ECMO and 1 of 4 patients undergoing 3 runs survived. Survival was more likely for patients with meconium aspiration. Primary pulmonary hypertension and total anomalous pulmonary venous return had low survival rates. Conclusions: A small subset of patients may require recannulation and a second ECMO course. Although survival may be achieved in more than one third of these patients, complication rates are increased during the second course. Specifically, neurologic, infectious, renal, and metabolic complication rates are increased. Long-term consequences of recannulation are unknown. Selection criteria identifying patients that may benefit from recannulation have not been established. J Pediatr Surg 37:845-850.  相似文献   
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