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101.
The possible hypocholesterolaemic properties of milk and fermented milk products have been investigated in groups of albino rats given a basal diet, basal diet plus cholesterol, and basal diet plus cholesterol together with whole milk or standard or bifidus yogurt. The yogurts were fortified with skim milk powder, condensed whey or lactose-hydrolysed condensed whey. After 30 d, triacylglycerols, total cholesterol, HDL-cholesterol and LDL-cholesterol were measured in serum. Whole milk and ordinary yogurt had no hypocholesterolaemic effect, but standard yogurt containing lactose-hydrolysed condensed whey and all bifidus yogurts lowered serum cholesterol. In general, yogurts changed HDL-cholesterol little, but tended to raise triacylglycerols. There was marked lowering of LDL-cholesterol in rats given either type of yogurt fortified with whey proteins. This study has demonstrated in a rat model that bifidus yogurts and yogurts fortified with whey proteins can reduce total and LDL-cholesterol, and suggests that if they have the same effect in human subjects they have potential value in cholesterol-lowering diets.  相似文献   
102.
Total parenteral nutrition (TPN) is used routinely to maintain patients with the Short Bowel Syndrome (SBS). Until recently, TPN has been the only available therapeutic modality for patients with SBS. Currently, it is the treatment of choice for such individuals and occasionally, when the loss of bowel is extensive, it may be the only way of maintaining life. Unfortunately, TPN is expensive and markedly restrains an individual's lifestyle. Despite the overall success of TPN, the numerous risks associated with its use and the many complications of having an intravenous indwelling for years have served as the stimulus for alternative treatments such as small bowel transplantation (SBT). The first attempts at small bowel transplantation in clinical medicine were by Detterling almost 25 years ago. Patient death or graft loss in these early attempts was caused by the failure to control graft rejection and/or the inability to prevent Graft Versus Host Disease (GVHD). A stimulus for renewed clinical interest in SBT was provided by Starzl et al in 1988 with a report of prolonged graft survival without graft rejection or GVHD in a patient who was the recipient of a multivisceral graft consisting of the entire small bowel and other abdominal organs. Since 1964, 78 Small Bowel transplants have been performed in humans. Several variations of the multivisceral procedure in which the liver and the small bowel constitute the major components of the graft were adopted. The longest survival has been in a child who is still alive with a working graft for more than two years, as reported by Goulet from Paris in 1989. The introduction in SBT of the new immunosuppressive agent FK 506 had provided results which are superior to those achieved with Cyclosporine A (CsA). This latter observation prompted the Pittsburgh group to initiate a large series of isolated and composite intestinal grafts. The remarkable results have demonstrated the clinical utility of intestinal transplantation. This paper will try to summarize the history of the small bowel transplantation until the end of the year 1992, with the current progress in use today.  相似文献   
103.
OBJECTIVE: To analyze the levels of free carnitine and carnitine esters in the muscles of patients with inflammatory myopathies. METHODS: Six men and 7 women with inflammatory myopathy and 25 age-matched healthy controls were studied. Free carnitine and carnitine esters in muscle homogenates were measured by a radiochemical procedure. Muscle histochemical staining and measurement of respiratory chain enzyme activity were also performed. RESULTS: Eleven patients had muscle carnitine insufficiency. Five of them had subsarcolemmal oxidative accumulations, 5 had lipid droplets, and 4 had defects of the respiratory chain enzyme complexes. CONCLUSION: Abnormal distribution of muscle carnitine is present in patients with inflammatory myopathies and could impair muscle function. Coexistent mitochondrial dysfunction may contribute to carnitine insufficiency.  相似文献   
104.
Macrophage activation and tumor necrosis factor-alpha (TNF-alpha) production are critical in tuberculosis immunity but may result in increased human immunodeficiency virus (HIV) expression and accelerated HIV disease progression in HIV-infected persons. Pentoxifylline inhibits expression of TNF-alpha and HIV. A double-blind, placebo-controlled study of adjunctive therapy with pentoxifylline (1800 mg/day) as a timed-release formulation was done in Ugandan HIV-infected patients with pulmonary tuberculosis. Subjects had early HIV disease (mean CD4 cell count, 380/microL) and did not receive other antiretroviral drugs. Pentoxifylline resulted in decreased plasma HIV RNA and serum beta 2-microglobulin and, in a subset of moderately anemic patients, improved blood hemoglobin levels. Trends were noted toward reduced TNF-alpha production in vitro and improved performance scores, but these did not reach statistical significance. No effect was noted on body mass, CD4 cell count, or survival. Additional studies of more potent TNF-alpha inhibitors in HIV-positive subjects with tuberculosis are warranted.  相似文献   
105.
A method for constructing decodable de Bruijn sequences   总被引:1,自引:0,他引:1  
We present two related methods of construction for de Bruijn (1946) sequences, both based on interleaving “smaller” de Bruijn sequences. Sequences obtained using these construction methods have the advantage that they can be “decoded” very efficiently, i.e., the position within the sequence of any particular “window” can be found very simply. Sequences with simple decoding algorithms are of considerable practical importance in position location applications  相似文献   
106.
107.
We reviewed the clinical features of 44 patients with invasive group A streptococcal (GAS) disease who were treated at two teaching hospitals in southern Taiwan from 1991 to 1994. Genes encoding streptococcal pyrogenic exotoxin types A (speA), B (speB), C (speC), and F (speF) and serotypes of M1, M6, and M12 were determined by polymerase chain reaction to target specific sequences in the 44 isolates recovered from these patients and in 28 isolates recovered from upper respiratory sites in 28 additional patients during the study period. The protease activity of these isolates was tested by using the casein plate method. Of the 44 patients with invasive diseases, 25 (57%) had no obvious underlying diseases, and 14 (32%) had preexisting neoplastic diseases or had previously used steroids. Twenty-five patients (57%) presented with cellulitis or necrotizing fasciitis, 24 (55%) had bacteremia, and eight (18%) had streptococcal toxic shock syndrome (STSS). Eight patients (18%) died of invasive GAS disease; seven had STSS, and seven had underlying diseases. All eight patients died within 48 hours after hospitalization. The presence of speA, speC, or speF was not implicated in any particular clinical syndrome in patients with invasive GAS disease. High-level protease activity and the M1 serotype of the isolates were significantly associated with the clinical signs of STSS and with mortality. M1 serotype and protease activity, as well as host immune status, might play significant roles in the pathogenesis of invasive GAS disease in Taiwan.  相似文献   
108.
Insufficient use of anti-inflammatory drugs, such as inhaled corticosteroids and cromoglycate, may contribute to the disease burden associated with asthma. Conversely, aggressive treatment of mild disease may result in avoidable costs and/or adverse drug effects. The aim of this study was to determine the relationship between asthma severity and inhaled corticosteroid/cromoglycate use in a large (n=4,909) random sample of children, aged 8-11 yrs, in NSW, Australia. Asthma and its treatment were assessed by questionnaire responses. Asthma, defined as diagnosis plus current wheeze, was present in 901 children (18% of the sample), of whom 225 (5%) had moderate asthma, defined as asthma plus additional symptoms (sleep disturbance), utilization (hospital, casualty), or disability (reduced activity, school absence). Use of inhaled corticosteroid/cromoglycate was reported by 636 children (13% of the sample). Determinants of use included: asthma diagnosis, current wheeze, and troublesome dry nocturnal cough. There was also a strong relationship between anti-inflammatory treatment and a multicomponent asthma severity score constructed for each child. Inhaled corticosteroids and/or cromoglycate were used by 56% of the children with asthma (24% daily) and by 76% of children with moderate asthma (42% daily). Undertreatment, defined as less than daily inhaled corticosteroids/cromoglycate in moderate asthma, was identified in 130 children (14% of those with asthma or 3% of the sample). Conversely, apparently aggressive treatment, defined as inhaled corticosteroid/cromoglycate use in children with persistent minimal symptoms (asthma severity score of less than 3) was identified in 101 children (2% of the sample). Although there were significant differences between regions in the choice of anti-inflammatory drugs and in the prevalence both of undertreatment and apparently aggressive treatment, there was no clear relationship to regional utilization of emergency and hospital services for asthma. Nevertheless, the frequency of undertreatment suggests an opportunity to reduce asthma morbidity by more consistent application of current therapeutic guidelines.  相似文献   
109.
The purpose of this study was to analyse the validity and the economic efficiency of a portable monitor of respiratory parameters (PMRP), used in a home setting for the diagnosis of sleep apnoea/hypopnoea syndrome (SAHS). Eighty nine patients with suspected SAHS were studied in two settings: in the sleep laboratory using full-polysomnography (full-PSG); and at the patient's home using a PMRP. In the home setting, 50 patients were assisted by a technician and 39 set up the equipment themselves. SAHS (apnoea/hypopnoea index (AHI) >10 events x h(-1) by means of full-PSG) was diagnosed in 75 of the 89 patients. An acceptable agreement was obtained between the AHI measured by full-PSG and PMRP, according to the Bland and Altman method of concordance (mean bias 2.56; 95% confidence interval 3.25). Sensitivity and specificity of PMRP were adequate for diagnostic purposes; however, their values rely on the prior PMRP-AHI cut-off point selected with reference to full-PSG-AHI >10. The clinical therapeutic decision taken after PMRP agreed with that taken with full-PSG in 79 patients (89%). Although 10% of the studies with an individual set-up needed repetition, both of the domiciliary modalities (with and without a technician's intervention) were, economically, about three times more efficient than full-PSG. In conclusion, we believe that patients with a suspected sleep apnoea/hypopnoea syndrome should initially be studied in a home setting with a portable monitor of respiratory parameters, since it is a reliable method with an acceptable cost-effective profile.  相似文献   
110.
Astronauts adopt a variety of neuromuscular control strategies during space flight that are appropriate for locomoting in that unique environment, but are less than optimal upon return to Earth. We report here the first systematic investigation of potential adaptations in neuromuscular activity patterns associated with postflight locomotion. Astronaut-subjects were tasked with walking on a treadmill at 6.4 km/h while fixating a visual target 30 cm away from their eyes after space flights of 8-15 days. Surface electromyography was collected from selected lower limb muscles and normalized with regard to mean amplitude and temporal relation to heel strike. In general, high correlations (more than 0.80) were found between preflight and postflight activation waveforms for each muscle and each subject: however relative activation amplitude around heel strike and toe off was changed as a result of flight. The level of muscle cocontraction and activation variability, and the relationship between the phasic characteristics of the ankle musculature in preparation for toe off also were altered by space flight. Subjects also reported oscillopsia during treadmill walking after flight. These findings indicate that, after space flight, the sensory-motor system can generate neuromuscular-activation strategies that permit treadmill walking, but subtle changes in lower-limb neuromuscular activation are present that may contribute to increased lower limb kinematic variability and oscillopsia also present during postflight walking.  相似文献   
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