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81.
Background: No bariatric operation has been documented to effect adequate weight loss in all patients. Patients with inadequate weight loss or significant weight regain with an anatomically intact short-limb gastric bypass, of which the Fobi pouch operation (FPO) for obesity is a modification, are usually revised to a distal Roux-en-Y gastric bypass (DRYGBP) to enhance weight loss. Method: A retrospective review of the charts of all patients who had a revision to a DRYGBP at our Center during an 8-year period was carried out and the findings analyzed. Results: 65 patients who had the FPO had a revision to the DRYGBP.Most were super obese patients who, even though they had lost significant weight, were still morbidly obese. Some were patients who had not lost adequate weight or <40% excess weight, and a small number were patients who requested more weight loss even though they had a BMI of < 35. 15 patients developed protein malnutrition requiring supplemental feeding. 6 required rerevision to short-limb gastric bypass. Conclusion: Revision of short-limb gastric bypass to DRYGBP usually enhances weight loss but at a cost of an increased incidence of protein malnutrition.  相似文献   
82.
In 1988, Travis and Arms reviewed the literature and collected data to develop a relationship between the octanol-water partition coefficient (Kow) and the uptake of organic compounds into milk and beef (Travis and Arms, 1988). These equations have been utilized for predicting biotransfer factors for organic chemicals when empirical data are lacking. During the external peer review of the draft US Environmental Protection Agency (EPA) guidance entitled Human Health Risk Assessment Protocol for Hazardous Waste Combustion Facilities (US EPA, 1998) and the development of Superfund's Ecological Soil Screening Levels (US EPA, 2000b), questions challenging the derivation and use of these equations were raised. The primary questions raised were: 1) Are the equations presented in Travis and Arms (1988) for the estimation of transfer of organic compounds from contaminated feed to beef and milk technically valid and reproducible? If so, (2) are the equations appropriate across the entire log Kow range? For these reasons, this study was undertaken to validate the original Travis and Arms equations, to review more recent literature, and. if appropriate, to add to the original Travis and Arms data set to obtain updated equations. This paper presents an evaluation of the original Travis and Arms equations, limitations to their use, and steps to reduce uncertainties associated with their use by updating with more current literature.  相似文献   
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84.
The clinicopathological associations of 33 singleton infants who died with intraventricular haemorrhage (IVH) without hyaline membrane disease (HMD) ('IVH only') were compared with those of 39 infants who died with IVH+HMD over the same gestation range in order to determine what factors other than those related to HMD may contribute to the pathogenesis of IVH. The incidence of 'IVH only' was inversely related to gestational age in the Hammersmith birth population, whereas the incidence of IVH+HMD rose to a peak at 28-29 weeks' gestation. Infants with 'IVH only' lived longer on average than those with IVH+HMD despite a lower birthweight and shorter gestation. Infants who died in the first 12 hours from 'IVH only' had suffered severe birth asphyxia but in those who died later the main symptom was recurrent apnoea. Fewer infants with asphyxia but in those who died later the main symptom was.recurrent apnoea. Fewer infants with 'IVH only' were given alkali therapy or were connected to the ventilator as compared to those with IVH+HMD, but there were no differences in alkali therapy in those who lived for 12 hours or more. In the 'IVH only' group there was a high incidence of haemorrhage from other sites and of bacterial infections. It is suggested that, in the absence of HMD, extreme immaturity is the main factor determining the occurrence of IVH. Birth asphyxia, apnoeic attacks, haemorrhage, and infections may play subsidiary roles, possibly through development of metabolic acidosis.  相似文献   
85.
To understand how gene expression patterns are established on the inactive X chromosome during development, we have studied the murine gene Smcx, which is expressed from both the active and inactive mouse X chromosomes. In all tissues assayed, Smcx only partially escapes X inactivation, with expression levels from the inactive X allele approximately 30-65% that of the active X allele. Additionally, inactive X expression levels differed between extraembryonic and embryonic tissues and among different tissues from newborn and adult mice. Imprinted extraembryonic tissue had the lowest levels of inactive X Smcx expression, whereas the highest levels were in heart. These data suggest that the chromosomal basis of X inactivation differs among tissues, perhaps reflecting differences in the timing or regulation of inactivation in these cell lineages.   相似文献   
86.
A group of girls is described with recurrent urinary tract infections characterized by predominantly lower tract symptoms. Clinical, laboratory, and radiography findings during the period of follow-up are presented. Infection persisted in most patients over several years. Response to medical and surgical treatment was unsatisfactory. The mean interval between the initial and most recent radiological study was 6 1/2 years. No case of renal parenchymal scarring was seen.  相似文献   
87.
A model of corrective gene transfer in X-linked ichthyosis   总被引:5,自引:0,他引:5  
Single gene recessive genetic skin disorders offer attractive prototypes for the development of therapeutic cutaneous gene delivery. We have utilized X-linked ichthyosis (XLI), characterized by loss of function of the steroid sulfatase arylsulfatase C (STS), to develop a model of corrective gene delivery to human skin in vivo. A new retroviral expression vector was produced and utilized to effect STS gene transfer to primary keratinocytes from XLI patients. Transduction was associated with restoration of full-length STS protein expression as well as steroid sulfatase enzymatic activity in proportion to the number of proviral integrations in XLI cells. Transduced and uncorrected XLI keratinocytes, along with normal controls, were then grafted onto immunodeficient mice to regenerate full thickness human epidermis. Unmodified XLI keratinocytes regenerated a hyperkeratotic epidermis lacking STS expression with defective skin barrier function, effectively recapitulating the human disease in vivo. Transduced XLI keratinocytes from the same patients, however, regenerated epidermis histologically indistinguishable from that formed by keratinocytes from patients with normal skin. Transduced XLI epidermis demonstrated STS expression in vivo by immunostaining as well as a normalization of histologic appearance at 5 weeks post-grafting. In addition, transduced XLI epidermis demonstrated a return of barrier function parameters to normal. These findings demonstrate corrective gene delivery in human XLI patient skin tissue at both molecular and functional levels and provide a model of human cutaneous gene therapy.   相似文献   
88.
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge.  相似文献   
89.
90.
目的:急性冠状动脉综合征(ACS)置入支架患者使用盐酸替罗非班、阿司匹林、氯吡格雷、低分子肝素(四联)时,评价泮托拉唑对消化道的保护作用.方法:选择ACS置入支架治疗的患者266例,随机分入观察组134例,对照组132例,所有患者均服用阿司匹林、氯吡格雷、低分子肝素和盐酸替罗非班.观察组患者静脉注射泮托拉唑40 mg/d 4~5天,之后改为泮托拉唑片剂40 mg/次,2次/天,服用30天.观察两组间30天全因死亡、再次心肌梗死、再次经皮冠状动脉介入治疗(PCI)、再次住院、颅内出血和消化道出血状况.结果:观察组134例患者30天内全因死亡5例、再次心肌梗死4例、再次PCI4例和再次住院8例;对照组132例患者分别为8例、6例、5例和13例,两组相比差异均无统计学意义(P>0.05);两组均无颅内出血发生.观察组消化道大出血0和总消化道出血事件3例,对照组分别为5例和15例,两组比较观察组消化道大出血和总消化道出血事件少于对照组(P<0.05),差异均有统计学意义.结论:ACS置入支架治疗的患者,盐酸替罗非班治疗是安全有效的,未见颅内出血发生.静脉注射和口服泮托拉唑并不增加30天全因死亡、再次心肌梗死、再次PCI和再次住院发生,同时可以减少30天内消化道出血发生率特别是消化道大出血事件的发生,具有良好的消化道保护作用和安全性.  相似文献   
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