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91.
The D2 peptide derived from an S. aureus fibronectin-binding protein (FnBP) was expressed on the surface of the icosahedral cowpea mosaic virus (amino acids 1-30 of D2) or on the rod-shaped potato virus X (amino acids 1-38 of D2), termed CPMV-MAST1 and PVX-MAST8, respectively. Mice and rats were immunized subcutaneously with CPMV-MAST1 and mice with PVX-MAST8 in adjuvant and high titres of FnBP-specific antibody were obtained. The mouse IgG was predominantly of the IgG2a and IgG2b isotypes, which strongly bound complement component C1q, suggesting a TH1-bias in the peptide-specific responses. Sera from mice and rats immunized with CPMV-MAST1 and from mice immunized with PVX-MAST8 were shown to completely inhibit the binding of fibronectin to immobilised recombinant FnBP and rat sera against CPMV-MAST1 were able to block adherence of S. aureus to fibronectin. These studies demonstrate that the D2 peptide is highly immunogenic when expressed on 2 different plant viruses and highlight the potential of plant virus-based vaccines to protect against S. aureus infections.  相似文献   
92.
In April 1998 an outbreak of salmonellosis amongst guests at a wedding feast was investigated. Of the 58 attendees interviewed 38 (66%) subsequently developed gastrointestinal symptoms. Stool cultures from 7 cases grew Salmonella Typhimurium RDNC A045. Food samples were culture-negative for Salmonella spp. A cohort study implicated spatchcock (RR 2.5, 95% CI 1.09-5.77) and scampi (RR 2.0, 95% CI 1.05-3.89). Temperature abuse and cross-contamination within the kitchen during preparation and cooking are likely to have been the main contributing factors to this outbreak. Control measures included staff education in safe food handling and improvements in poultry processing methods to minimise carcass contamination.  相似文献   
93.
Pentose shunt activity in developing chick retina and pigment epithelium was studied by measuring the rate of 14CO2 evolution from glucose selectively labelled in the C-1 and C-6 positions. In the retina, shunt activity declines from appreciable levels at stages 29–31 to minimal activity in the 2-week-old hatched chick. Overall retinal metabolism also declines up to stage 45, but dramatically increases again after hatching. Developing chick pigment epithelium has minimal shunt activity at all stages studied. In contrast, cultured chick pigment epithelium has appreciable shunt activity which is constant over a period of several weeks in culture. This appears to be a switch in biochemical differentiation which could form the basis at least in part for subsequent changes in cell types observed in cultured pigment epithelial cells byEguchi and Okada (1973).  相似文献   
94.
Creutzfeldt-Jacob disease manifests clinically as a form of presenile dementia. It is now known to be caused by a transmissible agent, probably a "slow virus". Rapidly progressive atrophic changes on serial computed tomograms of the brain are highly suggestive of the disease. Neuroradiographic and pathological findings in two cases of Creutzfeldt-Jacob disease are documented.  相似文献   
95.
Brigham and Women's Hospital initiated a study of the quality of care centering on self-reporting of potential medical injuries by providers. The goal of the study is to decrease the incidence of such injuries through a continuous quality methodology that integrates providers into the identification phase and incorporates all hospital employees in the development of new practices. This article provides an overview of the investigation methodology and discusses the conceptual relationships between clinical epidemiological analyses and industrial quality improvement.  相似文献   
96.
Summary Two years after para-aortic node radio-therapy following removal of a non-seminomatous germ cell tumour (NSGCT) of the left testis, M. R., a 32 year old caucasian male developed haemoptysis and a hoarse voice. Chest x-ray revealed a left hilar mass and serum alphafoetoprotein (AFP) and -human chorionic gonadotrophin (HCG) levels were elevated. In spite of VB3 [1] therapy plus cis-platinum and mediastinal radiotherapy his voice remained hoarse, although serum markers returned to normal, and the hilar mass was reduced in size.Four months after stopping therapy serum AFP levels began to rise, although no clinical evidence of recurrence could be discovered in abdomen, brain or chest.Chemotherapy was restarted using VP16-213 + bleomycin + cis-platinum [2]. After the first course of therapy the serum AFP level fell to normal and his hoarse voice disappeared.The patient received five courses of the above regimen, following which complete remission has been maintained for 7 months to date.This case suggests that VP16-213 combined with bleomycin + cis-platinum has great activity against NSGCT of the testis and may have a different spectrum of activity from vinblastine, bleomycin, and cis-platinum, making it a valuable addition to the drugs available for the management of these tumours.In this patient it would seem the complete eradication of the metastatic mass allowed complete and immediate recovery of function of the trapped nerve in spite of it having been paralysed for 15 months.  相似文献   
97.
Changes in serum zinc and copper levels were studied in 19 tumor bearing patients undergoing parenteral nutrition (TPN) for five to 42 days. Before initiation of intravenous feeding mean serum zinc and copper concentrations were within normal limits but during TPN levels decreased significantly below those measured prior to parenteral nutrition. During TPN nitrogen, zinc, and copper intake, urinary output and serum levels were studied prospectively in nine of these patients. These nine patients exhibited positive nitrogen retention based upon urinary nitrogen excretion, but elevated urinary zinc and copper excretion and lowered serum zinc and copper concentrations. Neither blood administration nor limited oral intake was consistently able to maintain normal serum levels of zinc or copper. Zinc and copper supplementation of hyperalimentation fluids in four patients studied for five to 16 days was successful in increasing serum zinc and copper levels in only two. The data obtained suggest that patients undergoing parenteral nutrition may require supplementation of zinc and copper to prevent deficiencies of these elements.  相似文献   
98.
Validity of the tritiated water assay technique for tyrosine hydroxylase activity as a qualitative method was demonstrated with mushroom tyrosinase. Using this method, isolated murine melanoma "tyrosinase" (L-dopa oxidase) showed no tyrosine hydroxylase activity. This finding supports previous studies in our laboratory which used a variety of histochemical and biochemical methods. The nonenzymatic production of tritiated water caused by tritium exchange with hydrogen peroxide complicates the use of the tritiated water assay technique with crude systems, since hydrogen peroxide is generated by a variety of oxidase reactions. For this reason, previous studies using the tritiated water assay technique with crude systems are ambiguous.  相似文献   
99.
A booklet, "Assessment of Maternal Nutrition," has been published by the American College of Obstetricians and Gynecologists in cooperation with The American Dietetic Association as a useful guide for physicians, nurses, dietitians, and nutritionists. Nutritional risks during pregnancy are clearly outlined. Clinical, dietary, and biochemical factors, as well as medical, obstetric, and social factors, are delineated as components of nutritional assessment. An A.D.A. Liaison Committee had major responsibility for the development of the "Eating Habits Questionnaire," a tool to screen dietary intake for major deficits and excesses, which is included in the booklet. It should be useful also as a starting point for nutrition education. Additional evaluation of the use and reliability of the screening tool is recommended.  相似文献   
100.
A randomised controlled trial was carried out on 100 patients to compare the effects of discharge after certain pre-specified clinical criteria had been fulfilled--"right" stay--with those of discharge at an arbitrary 10 days after surgery--"fixed" stay. The operations concerned (cholecystectomy and vagotomy) were more hazardous than those previously included in studies of early discharge. Patients in the right-stay group were discharged, on average, 7-6 days after operation--that is, two days earlier than those in the fixed-stay group. In terms of clinical progress, social factors such as return to work, and the acceptability to patients and relatives of the implications of right stay, patients in this group fared as well as those in the fixed-stay group, and in some respects slightly better. Right stay entailed the transfer of some work from hospital to community medical and nursing staff, but this also was acceptable. The concept and use of the right-stay principle is of value in planning the postoperative discharge of suitable patients.  相似文献   
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