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651.
This study was undertaken to determine the effect of low-dose gamma irradiation on aseptically admixed total parenteral nutrition (TPN) solutions to which large inocula of three test bacterial species were added. Microbiological safety levels were quantified in terms of sterility assurance levels (SALs), indicating the probability of contamination occurring expressed as 10-n. The radiation sensitivity (D10 values) of test bacteria in TPN solutions inoculated with a series of bacteria recognized as common contaminants of these products, was determined. Attainable SALs of TPN solutions containing test bacteria were subsequently calculated from the D10 values. Results showed that a minimum absorbed radiation dose as low as 1.5 kGy improved the SAL of aseptically prepared TPN solutions from a probability value of 10-3 to a value of less than 10-8 for the microorganisms investigated. At an absorbed dose as high as 8.3 kGy, no measurable changes in amino acid, electrolyte, glucose and lipid components of the solutions were detected. These findings have important implications for the enhancement of microbiological safety levels of aseptically prepared intravenous fluids in general.  相似文献   
652.
Effects of taurine on rat aorta in vitro   总被引:3,自引:0,他引:3  
The effects of taurine on vascular tone of isolated thoracic aortic rings were investigated. We have observed that: 1) taurine is able to induce reduction of the basal contractile tone; 2) taurine exerts a relaxing action in artery segments preconstricted with high potassium medium noradrenaline; 3) the effect of taurine is either dependent on endothelium, nor mediated by adrenoceptors or muscarinic cholinoceptors; 4) in vessels with basal tone or in those preconstricted with noradrenaline, the presence of endothelium reduces the taurine-induced relaxation; 5) the actions of taurine are independent of extracellular calcium; 6) taurine increases the vasodilatation induced by a perfusion with a calcium-free medium. The physiological role of taurine in the maintenance of vascular tone in normal and pathological situations is discussed.  相似文献   
653.
Parry–Romberg syndrome: A possible association with borreliosis   总被引:1,自引:0,他引:1  
Progressive facial hemiatrophy or Parry-Romberg syndrome is a rare entity characterized by unilateral atrophy of the skin, subcutaneous tissue and the underlying bony structures. This syndrome has many features of linear scleroderma 'en coup de sabre' but is distinguished by more extensive involvement of the lower face with only slight cutaneous sclerosis. The onset typically occurs in childhood or young adult years. The aetiology of the condition is unknown. A case of progressive hemifacial atrophy occurring in a 30-year-old woman is reported, in which the aetiology is thought to be Lyme disease, a borrelial infection first recognized in 1975 that has since become the most commonly reported vector-borne disease in the world. No sure link is established between these two disease states, but their coincident occurrence in this patient is noted. We hypothesize that the aetiology of Parry-Romberg syndrome involves borreliosis.  相似文献   
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Some now seemingly bizarre childbirth practices of the Middle Ages, such as "child-breaking," baptism in utero, excessive modesty, and use of the obstetric chair and tools, are described. Also outlined are the slow, painful steps in the climb out of these dark times: education for midwives, permitting the male in the lying-in room, aseptic technique, und the use of anesthesia.  相似文献   
656.
Cross sectional data reporting the height, weight, and body mass index of UK patients with cystic fibrosis are presented. During the first decade of life height and weight in patients with cystic fibrosis are maintained at about 0.5 SD below those of the general population, which reflects an improvement over earlier published observations. Postpubertal stature and weight maintenance in the cystic fibrosis population still show substantial deficits which may be related to treatment.  相似文献   
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659.
A directly agglutinating murine monoclonal antibody of the IgG3 isotype has been produced after mice were immunized with papain-treated Bombay phenotype, e-positive red cells (RBCs). The antibody strongly agglutinated all e-positive RBCs and gave negative reactions with RBCs from Rhnull persons and those homozygous for Rh deletion genes. Variable reactivity was found with e-negative RBCs, ranging from weak to negative with R2R2, slightly stronger with r"r", and stronger still with RzRz. These reactions, together with results from tests with a large panel of Rh-variant RBCs, suggested a specificity for an epitope that is part of the e mosaic but is also expressed at least partially on e-negative RBCs and is influenced by the presence of C. This antibody has been standardized for use as a screening reagent for R2R2 cells by a microplate technique, and over 6000 donations have been screened in this way. No discrepancies have been found in confirmatory tests for e-negative status using human anti-e.  相似文献   
660.
The authors obtained atrophied and hypertrophied small intestinal tissue from a patient undergoing jejunoileal (JI) bypass reversal. Tissue from both segments was examined for insulin, insulin-like growth factor-I (IGF-I) and IGF-II receptors, and alkaline phosphatase and sucrase. We were interested in the potential of the atrophied segment to respond to luminal stimulation once the food train was re-established. Within the atrophic segment, flow cytometric evaluation of the receptors revealed (expressed as percent positive staining cells): Insulin, 17.1%; IGF-I, 33.6%; and IGF-II, 60.8%, while the immunoreactive sucrase was 87.7% and alkaline phosphatase was 88.6%. Actual sucrase activity (expressed as glucose generated) in this segment was 17.9ng/min/μg protein and alkaline phosphatase was 28.0 U/L/μg protein as assessed by conventional methods. Receptor evaluation in the hypertrophic segment demonstrated 9.7% positive staining cells for insulin, 26.6% for IGF-I and 70.2% for IGF-II. Immunoreactive sucrase was 91.2% and alkaline phosphatase was 91.4%. Enzyme activity for sucrase was 10.4ng/min/μg protein and for alkaline phosphatase was 59.4U/L/μg protein. This data suggests that even in atrophied bowel insulin and IGF receptors as well as sucrase and alkaline phosphatase enzymes are present and may assist in the rapid recovery of the atrophied portion following reversal of the JI bypass.  相似文献   
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