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1.
C Harro GL Braden AB Morris GS Lipkowitz RL Madden 《Canadian Metallurgical Quarterly》1997,24(5):955-957
Nontuberculous mycobacteria are increasingly recognized as important pathogens in peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD). Mycobacterium gordonae rarely causes human infection and is the least likely mycobacterium to produce clinical infection in CAPD patients. We describe a patient with persistent M. gordonae peritonitis acquired while undergoing CAPD. During 18 months of treatment, clinical improvement occurred but a microbiological cure could not be achieved. Principles of therapy for mycobacterial peritonitis developing during CAPD are reviewed, and potential explanations for our patient's failure to respond to therapy are discussed. 相似文献
2.
GS Kelner JM Minnerath MK Jenkins R Jemmerson 《Canadian Metallurgical Quarterly》1993,23(8):1992-1998
Male and female A/J mice were examined for their ability to elicit T lymphocyte and antibody (Ab) responses to the male-specific Ag, mouse testicular cytochrome c (Mt cyt). T lymphocytes from both male and female mice primed in vivo responded to the Ag in in vitro proliferation assays, and the dose-response curves were statistically indistinguishable. In addition, similar levels of Ab to Mt cyt were observed in immunized male and female mice. The B cells producing the Ab had switched isotypes to IgG1 and IgG2a, indicating that the self-reactive T helper (Th) cells in male mice were functional. Thus, male mice do not appear to be immunologically tolerant to Mt cyt, at least at the Th and B lymphocyte levels. No evidence for disease was found in male mice primed with Mt cyt. Major histocompatibility complex (MHC) class II-positive antigen-presenting cells are present in the testes and these were shown in vitro to process and present Mt cyt to a T cell hybridoma specific for the synthetic peptide Mt cyt 93-104. However, the hybridoma was not activated in the absence of exogenous Mt cyt 93-104 or Mt cyt, indicating that endogenous Mt cyt is not normally processed in sufficient quantity to effectively load MHC class II molecules with this particular Mt cyt-derived peptide. Notwithstanding any immunologic privilege of the testes, the lack of tolerance to Mt cyt and its failure to elicit an autoimmune disease could extend from the low levels of processed Mt cyt Ag available for T cell recognition. The T cell response elicited by Mt cyt contrasts the lack of response to mouse somatic cytochrome c which differs from Mt cyt at 13 amino acid residues and is expressed in most tissues and at higher levels. 相似文献
3.
S Moss B Ibbotson H Prosser D Goldberg P Patel N Simpson 《Canadian Metallurgical Quarterly》1997,32(6):344-354
The Psychiatric Assessment Schedule for Adults with Developmental Disability (PAS-ADD) is a semi-structured interview for use with respondents who have learning disability and for key informants. This report investigates the ability of the instrument to detect symptoms that had been found to exist during routine clinical assessment of the patients. Field trials involved 95 referred patients with learning disability and a key informant for each sample member. Clinical opinions of the referring psychiatrists were sought using a symptom checklist. Referrer checklist symptoms and PAS-ADD data were both factor analysed. Validity testing involved (a) computation of correlations between PAS-ADD factors and checklist data and (b) comparison of PAS-ADD and referrers' diagnoses. Results indicated good validity for the PAS-ADD in relation to psychotic symptoms and depressive symptoms. Anxiety symptom identification was not well validated, probably due to small numbers. Expansive mood identified by the referrers was not detected by the PAS-ADD because there is currently no corresponding section in the interview. Where the PAS-ADD produced a diagnosis (in 58 members of the sample), 44 were in agreement with the referrer. Probability of diagnosis by PAS-ADD increased with the number of relevant active symptoms identified by the referrer. The PAS-ADD has been shown in a previous report to have the sensitivity to detect mental disorders not known to psychiatric services. For psychotic and depressive conditions, our results showed that symptom detection was in good agreement with the information provided by the referring psychiatrists on their patients. The PAS-ADD needs a section on hypomania and further investigation of its detection of anxiety disorders. 相似文献
4.
There is growing evidence that the amino-terminal globular domain of apolipoprotein B (apoB) is essential for lipoprotein particle formation in the hepatic endoplasmic reticulum. To identify the structural requirements for its function in lipoprotein assembly, cysteine (Cys) pairs required to form the seven disulfide bonds within the amino-terminal 21% of apoB were replaced in groups or individually by serine. Substitution of Cys pairs required for formation of disulfide bonds 1-3 or 4-7 (numbered from amino to carboxyl terminus) completely blocked the secretion of apoB28 in transfected HepG2 cells. To identify the specific disulfide bonds required for secretion, Cys pairs were mutated individually. Substitution of Cys pairs required for disulfide bonds 1, 3, 5, 6, or 7 had little or no impact on apoB28 secretion or buoyant density. In contrast, individual substitution of Cys pair 2 (amino acid residues 51 and 70) or 4 (218 and 234) severely inhibited apoB28 secretion and its capacity to undergo intracellular assembly with lipid. The same assembly and secretion defects were observed when these mutations were expressed as part of apoB50. These studies provide direct evidence that the ability of the internal lipophilic regions of apoB to engage in the recruitment and sequestration of lipid during translation is critically dependent upon a structural configuration contained within or affected by the amino-terminal 5% of the protein. 相似文献
5.
Previous studies in children have shown inconsistent, poorly reproducible GH responses to exogenous GH-releasing factor (GRF), with wide individual variability. In the present study, we tested the hypothesis that prior administration of the long-acting somatostatin analog, SMS 201-995 (SMS), will enhance GH responsiveness to a subsequent GRF challenge. Two study protocols were employed in 37 children with short stature [M = 31, F = 6, ages 11.8 +/- 1.6 yr (mean +/- SEM), height -2.25 +/- 0.55 SDS (SD scores)]. In both studies, each subject served as his/her own control. In the first study, which was designed to determine optimal SMS dose and regimen, SMS, in doses ranging from 0.8-2.2 micrograms/kg sc, was randomly administered or omitted at 0800 h after an overnight fast, and a GRF bolus (50 micrograms, iv) was given 4 h later. In the second study, we employed a protocol identical to study 1 except for the use of standard doses of SMS (1 microgram/kg, sc) and GRF (1 microgram/kg, iv) and an additional 1-h delay of the GRF injection. Plasma GH levels were measured every 20 min from 0800 h until 2 h after the GRF injection in both studies. In study 1 (n = 12; M = 10, F = 2), SMS significantly suppressed spontaneous GH secretion (expressed as the mean +/- SEM GH AUC during the 4-h SMS-GRF interval, AUC 1:2.2 +/- 0.4 vs. 6.2 +/- 0.9 micrograms/L.h; P < 0.001), GH responsiveness to GRF (GH AUC during the 2 h after the GRF injection, AUC 2: 41.5 +/- 7.8 vs. 85.0 +/- 13.5 micrograms/L.h; P < 0.001), and the GH peak response (17.4 +/- 3.1 vs. 36.0 +/- 6.2 micrograms/L; P < 0.001), compared to control tests. In contrast, in study 2 (n = 25; M = 21, F = 4), whereas spontaneous GH secretion was still suppressed during the 5-h SMS-GRF interval (AUC 1:3.8 +/- 0.4 vs. 7.4 +/- 1.1 micrograms/L.h; P < 0.001), both the GH peak response (56.7 +/- 5.5 vs. 30.5 +/- 3.0 micrograms/L; P < 0.0001) and the GH AUC (AUC 2: 103.7 +/- 10.3 vs. 77.5 +/- 6.8 micrograms/L.h; P < 0.05) after GRF administration were significantly augmented by pretreatment with SMS, compared to control tests. Taken together, these results indicate that a priming SMS dose of 1 microgram/kg has a significant permissive effect on GH responsiveness to exogenous GRF administered 5 h later.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
6.
E La Hey J de Vries CT Langerhorst GS Baarsma A Kijlstra 《Canadian Metallurgical Quarterly》1993,116(3):327-340
After reviewing the records of 111 patients with Fuchs' heterochromic iridocyclitis, we studied the therapy and prognosis of secondary glaucoma in 30 of these 111 patients (27%) who had glaucoma or could be considered glaucoma suspects. Maximal medical therapy was unsuccessful in 22 of the 30 patients (73%). Surgical intervention (mostly trabeculectomies, half with 5-fluorouracil) successfully controlled intraocular pressure (< or = 21 mm Hg with or without medication) in 13 of the 18 operated-on patients (72%) after a mean follow-up of 26 months. All successfully operated-on patients retained a visual acuity of 20/80 or better. We had favorable results, possibly because of modern surgical techniques (use of 5-fluorouracil, sodium hyaluronate) or earlier surgical intervention, or both. 相似文献
7.
Ipratropium bromide is a synthetic derivative of atropine with little absorption when used in inhalation, and therefore little secondary effects. The authors review its pharmacological properties and therapeutic efficacy in the treatment of asthma in children. Combined nebulized inhalation of ipratropium bromide and beta 2 sympathomimetic results in a more efficient and more sustained bronchodilatation than beta 2 sympathicomimetic alone in the treatment of acute asthma in children. Ipratropium bromide should be usefully introduced in the therapeutic scheme of acute asthma in children. Further studies will be necessary in order to determine its efficacy and tolerance in infants. 相似文献
8.
Moss C.D. Teixeira F.L. Yang Y.E. Jin Au Kong 《Geoscience and Remote Sensing, IEEE Transactions on》2002,40(1):178-186
A three-dimensional (3D) finite-difference time-domain (FDTD) scheme is introduced to model the scattering from objects in continuous random media. FDTD techniques have been previously applied to scattering from random rough surfaces and randomly placed objects in a homogeneous background, but little has been done to simulate continuous random media with embedded objects where volumetric scattering effects are important. In this work, Monte Carlo analysis is used in conjunction with FDTD to study the scattering from perfectly electrically conducting (PEC) objects embedded in continuous random media. The random medium models under consideration are chosen to be inhomogeneous soils with a spatially fluctuating random permittivities and prescribed correlation functions. The ability of frequency averaging techniques to discriminate objects in this scenarion is also briefly investigated. The simulation scheme described in this work can be adapted and used to help in interpreting the scattered field data from targets in random environments such as geophysical media, biological media, or atmospheric turbulence 相似文献
9.
Shokooh-Saremi M. Ta'eed V.G. Littler I.C.M. Moss D.J. Eggleton B.J. Ruan Y. Luther-Davies B. 《Electronics letters》2005,41(13):738-739
The first ultra-strong, near-perfect, raised-apodised Bragg gratings in As/sub 2/S/sub 3/ chalcogenide rib waveguides using /spl lambda/=532 nm light and a modified Sagnac holographic writing setup are demonstrated. Good agreement is achieved between the experimental results and the numerical modelling of the gratings using the transfer matrix analysis for thin film structures. 相似文献
10.
HJ Voeller M Augustus V Madike GS Bova KC Carter EP Gelmann 《Canadian Metallurgical Quarterly》1997,57(20):4455-4459
Loss of heterozygosity at chromosome 8p21-22 is common in human prostate cancer, suggesting the presence of one or more tumor suppressor genes at this locus. A homeobox gene that is expressed specifically in adult human prostate, NKX3.1, the expression of which is regulated by androgen, maps to chromosome 8p21. Fine structure in situ mapping showed that NKX3.1 is proximal to MSR32 (macrophage scavenger receptor type II) and LPL (human lipoprotein lipase) and very close to NEFL (human neurofilament light chain) on 8p21. Single-strand conformational polymorphism analysis of 48 radical prostatectomy cancer specimens and 3 metastases for the entire coding region of NKX3.1 showed no tumor-specific sequence alterations in 50 specimens and total absence of the gene in 1 specimen known to have a biallelic deletion of 8p21. NKX3.1 was found to have a polymorphism at nucleotide 154 in codon 52 that resulted in a CGC-->TGC sequence change and an Arg-->Cys amino acid alteration (R52C). This polymorphism was present in 20% of DNA samples. If NKX3.1 is a target of the 8p21 LOH, it is not via disruption of the coding region of the gene. 相似文献