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51.
Five patients suffering from periodic affective disorders with short mood-cycles were treated with rubidium chloride, producing peak erythrocyte concentrations between 9 and 13 mmol/l. Loading with rubidium was associated with decreased total body potassium, but red-cell potassium was unchanged. Regular mood-cycling was disturbed, together with the associated body-weight changes. There was a slight extracellular "metabolic" acidosis. Electrolyte concentrations fluctuate abnormally in these patients, and two muscle biopsy specimens had very low potassium contents.  相似文献   
52.
A randomized, prospective clinical trial was performed to compare the Marco MT-336 automated perimeter with Goldmann-type manual kinetic perimetry. The number of true and false, positive and negative scotomas were counted, as determined by the findings on the Marco perimeter, assuming that the Goldmann perimeter was the "gold standard." For eight of the available programs, the accuracy specificity, sensitivity, positive predictive value and negative predictive value were determined. Chi-squared testing across and within programs was performed to determine the degree of agreement between the tests as to the presence or absence of scotomas. Additionally, McNemar's test was used to determine the amount of random disagreement between the two methods of testing. Although there are inherent difficulties in the analysis, the authors conclude that the Marco MT-336 perimeter is an accurate instrument for both detecting and ruling out the presence of visual field defects.  相似文献   
53.
Oesophageal duplications are rare congenital abnormalities. Most of them do not communicate with the oesophageal lumen. We present a very uncommon finding of communicating oesophageal duplication in which the connection between the oesophagus and its duplicate portion was demonstrated by CT.  相似文献   
54.
The overall success of orthotopic liver transplantation (OLTX) includes not only survival, but quality of life (QOL) as well. We studied one controversial group of OLTX recipients, patients transplanted for alcoholic liver disease (Laennec's), to determine if their post-OLTX QOL was similar to that of patients transplanted for non-alcoholic liver disease (non-Laennec's). Over a 10-yr period, patients undergoing OLTX at our institution were asked to complete a QOL questionnaire addressing a wide range of topics from demographics and employment to symptom distress/frequency, activities of daily living, and effect of loss of health on daily life. Twenty-four Laennec's and 100 non-Laennec's OLTX recipients completed the questionnaire at both their 2- and 5-yr follow-up visits at our institution. Both groups were well-matched in age, race, and patient location status at the time of OLTX. No significant differences could be detected between Laennec's and non-Laennec's scores regarding overall QOL, including one's ability to function, health perception, and self-perception at 2 and 5 years post-OLTX, and between 2 and 5 years post-OLTX. Although not between groups, a significant difference was noted regarding patients' satisfaction with life, with less satisfaction reported at the 5-yr versus the 2-yr time point post-OLTX. Rates of current/recent employment between both groups were also similar at 2 years post-OLTX, and again at 5 years post-OLTX. We conclude that overall QOL and employment levels appear similar between patients transplanted for alcoholic and non-alcoholic liver disease. This similarity appears to extend to 5 years post-OLTX.  相似文献   
55.
The Dallas (Texas) Public Schools established the first school-based health center in the United States in 1969. In 1993 a partnership between two school principals, a school mental health professional, and the medical director of the county mental health center was the impetus for the first comprehensive school-based mental health center in Texas. In 1995 the programs joined together as Youth and Family Centers (YFCs) to provide physical health, mental health, and other support services to students and their families. The 10 strategically located school-based centers are directed by licensed mental health professionals employed by the district who lead a multidisciplinary team of physical health and mental health providers. Students served by the YFCs have fewer discipline problems, course failures, and school absences.  相似文献   
56.
The aim of this study was to assess the bioequivalence of H13CO-3 and H14CO-3, by administering both labels simultaneously by single infusion and comparing their recovery in breath CO2 and urinary urea. Six healthy male subjects (age range 24-41 years; weight 76.7 (sd, 18.6) kg; height 1.79 (sd 0.05) m) were infused with unprimed solutions of HCO3- (110.0 mmol/kg) labelled with 13C (0.76 mmol 13C/h) and 14C (48 Bq/h) at a constant rate for 6 h, in a whole-body calorimeter (1400 litres) for measurement of CO2 production. Samples of breath were collected hourly in a Douglas bag and all urine was collected into two batches (0-4 h and 4-6 h) for estimating recovery of infused label by measurement of enrichment or specific activity. Recovery in breath CO2 of both labels increased from about 25 % for the first hour to 88 % and above for hours 3-4 onwards. Mean recovery of 13C in breath CO2 was slightly higher than that of 14C for all periods (mean difference always less than 1 % of infused label) but was significant only for the first 3 h (P < 0.05). Recovery of 14C in urea was significantly higher (P < 0.01) than 13C, but was confounded by substantial variability and uncertainties concerning 13CO2 background enrichments. These results suggest that there is no compelling need to alter factors currently used for recovery of 14C in breath when using 13C instead, and vice versa.  相似文献   
57.
Leavitt  SA; DeAngelo  AB; George  MH; Ross  JA 《Carcinogenesis》1997,18(11):2101-2106
Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.   相似文献   
58.
BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent.  相似文献   
59.
60.
Immediate closed reduction and application of a well-molded hip spica cast is a safe and effective treatment option for closed, isolated femur fractures in children who weigh between 10 and 100 pounds. Between 1988 and 1996, 190 immediate hip spica casts were placed on children with isolated femoral shaft fractures who weight between 10 and 100 pounds. Fifteen patients were lost to followup leaving 175 children who were evaluated and followed up for at least 2 years after the hip spica cast was removed (range 2-10 years). The femur fractures were reduced closed and placed in a 1 1/2 hip spica cast in the emergency room with the patient under conscious sedation or in the operating room with the patient under general anesthesia. All of the children returned home within 24 hours of the procedure. All 175 femur fractures united within 8 weeks. The only complication was a refracture in a 25 pound child who fell 1 week after the cast was removed. No significant residual angular deformities were present in any of the children at last followup. None of the children required external shoe lifts, epiphysiodesis, antibiotics, irrigation and debridements, or limb lengthening procedures for leg length inequalities. The authors think that immediate closed reduction and placement of a well-molded hip spica cast is a safe and reliable treatment option for isolated, closed femur fractures in children from birth to 10 years of age who weigh less than 80 pounds.  相似文献   
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