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51.
M. Rogol I. Sechter H. Falk Y. Shtark S. Alfi Z. Greenberg R. Mizrachi 《European journal of clinical microbiology & infectious diseases》1983,2(6):588-590
A report is given on an outbreak of enteritis which occurred in July 1982 in a kibbutz near Jerusalem. About 150 of the 512 inhabitants were affected.Campylobacter jejuni was isolated from ten out of 42 stool samples examined toward the end of the outbreak. No other enteric pathogen was found. Strong circumstantial evidence indicated an association between the outbreak and the use of water from an unprotected reservoir, but no bacteriological confirmation was obtained. 相似文献
52.
Linkage of Chido and HL-A 总被引:6,自引:0,他引:6
53.
Oxytocin treatment in rats induces long-lasting antistress and growth promoting effects. This study investigated whether prolyl-leucyl-glycinamide (PLG) (the c-terminal tripeptide of oxytocin) or tocinoic acid (the ring structure of oxytocin) could induce some of these effects in male rats. For this purpose, PLG (2 or 10 mg/kg, s.c.) or tocinoic acid (1 mg/kg, s.c.) was administered to rats once a day for 3 or 5 days. Blood pressure, heart rate, spontaneous motor activity, nociceptive thresholds, and the survival of ischaemic musculocutaneous flaps were measured. In addition, endogenous oxytocin levels and plasma levels of some hormones known to be influenced by oxytocin were determined. PLG (2 mg/kg, s.c., but not 10 mg/kg, s.c.) decreased diastolic blood pressure (p<0.05) and locomotor activity (p<0.05). PLG (10 mg/kg, s.c.) decreased gastrin (p<0.05) and endogenous oxytocin levels in plasma (p<0.01). Tocinoic acid decreased locomotor activity (p<0.05), but did not affect any of the other parameters measured. In conclusion, this study showed that both PLG and tocinoic acid decrease locomotor activity. In addition, PLG also induced some other effects similar to those induced by oxytocin treatment but when administered in high doses it decreased oxytocin levels. 相似文献
54.
Kerstin Lyttkens MD Tomas Kirkhorn Mikael Kehler Berth Andersson Anders Ebbesen Peter Hochbergs Olof Jarlman Claes-Göran Lindberg Nils-Gunnar Holmer 《Journal of digital imaging》1994,7(2):61-68
Paper copies of digital radiographs printed with the continuous ink-jet technique have proved to be of a high enough quality for demonstration purposes. We present a study on the image quality of ink-jet printed paper copies of digital chest radiographs, based on receiver operating characteristic (ROC) analysis. Eighty-three digital radiographs of a chest phatom with simulated tumors in the mediastinum and right lund, derived from a computed radiography (CR) system were presented in two series of hard copies as ink-jet printed paper copies and as laser recorded film. The images, with a matrix of 1,760×2,140 pixels, were printed with a spatial resolution of 10 pixels/mm in the CR film recorder as well as in the ink-jet printer. On film, every image was recorded in two versions, one optimized for the mediastinum and one for the lungs. On paper, only one image was printed; this constituted an effort to optimize both the mediastinum and the lungs. The ink-jet printed images, printed on a matt coated paper, were viewed as on-sight images with reflected light. The exdaminations were reviewed by six radiologists, and ROC curves were constructed. No significant difference was found between the performance of film and that of ink-jet paper prints. Because the cost for a paper copy is only a tenth of that of film, remarkable cost reductions can be achieved by using the ink jet technique instead. Our results show that further quality studies of ink-jet printed images are worthwhile. 相似文献
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57.
Peptide motifs of closely related HLA class I molecules encompass substantial differences. 总被引:11,自引:0,他引:11
Olaf Rtzschke Kirsten Falk Stefan Stevanovi Günther Jung Hans-Georg Rammensee 《European journal of immunology》1992,22(9):2453-2456
The peptides presented by major histocompatibility complex class I molecules adhere to strict rules concerning peptide length and occupancy by certain amino acid residues at anchor positions. Peptides presented by HLA-A*0201 molecules, for example, are generally nonapeptides requiring Leu or Met at position 2 and an aliphatic residue, predominantly Val, at position 9. A closely related molecule, HLA-A*0205, differing from the former at four amino acid residues, has a related but substantially different peptide motif. A*0205-presented peptides are still nonapeptides, and position 9 is still aliphatic, although it is preferentially occupied by Leu instead of Val. Position 2 not only allows aliphatic residues but also polar ones. Occupancy at position 6, considered as an auxiliary anchor in A*0201, as well as non-anchor residues at positions 3, 4, and 8 are relatively well conserved between the two peptide motifs. Thus, although a number of the T cell epitopes presented by the two HLA-A2 forms is expected to be identical, a considerable number of epitopes should be different. 相似文献
58.
Cook Graham P.; Meyer Kerstin B.; Neuberger Michael S.; Pettersson Sven 《International immunology》1995,7(1):89-95
The activity of the IgH (Eµ) enhancer in the T lymphocytelineage has been investigated using both transgenic mice andtransfection studies. Thymocyte fractionation experiments indicatethat a transgene consisting of the bacterial chloramphenicolacetyl transferase (CAT) gene, linked to Eµ and the SV40early promoter (Eµ–CAT), is expressed only in thymocyteswith a mature medullary phenotype and not in immature cells.Transfection of this same construct into two thymoma cell linesrepresenting different stages of thymocyte development mimicsthe pattern of activity observed in vivo. Further transfectionexperiments suggest that this pattern of expression might beattributed to the differential activity of the E2E3 and octanucleotidemotifs of Eµ during development. In contrast, an Ig transgene(linked to Eµ and an Ig V promoter) is expressed in themajority of thymocytes. We envisage that the different patternsof expression of the two transgenes reflect interactions betweentheir respective promoters and the factors which are bound toEµ at different stages of thymocyte development. Althoughdiffering in their pattern of expression within the thymus,the two transgenes share the property of extinction in peripheralT lymphocytes. These results indicate that the expression ofEµ-linked transgenes in the thymus cannot simply be explainedby activation of the enhancer in a lymphoid progenitor cellprior to B/T lineage divergence. Rather, the enhancer (or componentsof it) must be independently activated (and inactivated) duringT lymphocyte development. Furthermore, this activity is consistentwith the developmental timing of Ig DH–JH rearrangementsin these cells. 相似文献
59.
60.
This study examined the effects of anonymity, gender, and erotophilia on the quality of self-reports of socially sensitive health-related behaviors. A sample of 155 male and 203 female undergraduate students was randomly assigned to an anonymous and a confidential (i.e., nonanonymous) assessment condition. Gender, erotophilia, self-reports (of substance use, sexual behaviors, illegal activity), and perceived item threat were assessed by questionnaire. Data quality was strongly affected by experimental condition and gender. Thus, terminations were more frequent in the confidential condition and among women. In the confidential condition, women were significantly more likely to prefer not to respond to sensitive items compared to men. Both female gender and confidential condition were associated with lower frequency reports of sensitive health behaviors, and greater perceived threat of the assessment questions. Self-reported engagement in sensitive behaviors was positively related to both perceived question threat and erotophilia. Path analyses suggest that question threat mediates the effects of anonymity manipulations and gender on data quality (item refusal, termination), and that erotophilia mediates the effects of gender on incidence and frequency self-reports. The results indicate that anonymous assessments as well as male gender are associated with better data quality. 相似文献