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91.
Zusammenfassung
Eine neu aufgetretene Dyspnoesymptomatik und eine symmetrische, apikal betonte retikulonodul?re Zeichnungsvermehrung im R?ntgen-Thorax
bei jungen rauchenden Erwachsenen müssen an das seltene Krankheitsbild der pulmonalen Histiocytosis X denken lassen. Klinischer
Befund, laborchemische- und Lungenfunktionsuntersuchungen zeigen unspezifische Befunde. Neue radiologische Verfahren wie die
hochaufl?sende Computertomographie (HRCT) leisten bei gezielter Indikationsstellung eine entscheidende differentialdiagnostische
Hilfestellung.
Dieser Fall verdeutlicht die M?glichkeit einer Diagnosesicherung durch transbronchiale Biopsien unter Verzicht auf offene
Lungenbiopsien. Eine ambulante Diagnostik war m?glich, das h?here Risiko eines operativen Eingriffes konnte vermieden werden.
Die Indikation zur Therapie ist nicht gesichert und wird daher durch den Grad der subjektiven bzw. funktionellen Einschr?nkung
sowie den Verlauf bestimmt. 相似文献
92.
Macrophages, dendritic cells or B lymphocytes have been shownto play a major role in the presentation of soluble antigensto CD4+ T cells. In contrast, the capacity of these cells topresent particulate antigens such as bacterial or parasiticantigens to T cells remains controversial. To investigate thisquestion, well defined particulate antigens were prepared bycovalent linkage of proteins or peptides to 1 µm in diametersynthetic microspheres. The T cell immunogenicity of such particulateantigens was analyzed in vitro and in vivo. In vitro, a solubleprotein such as hen egg lysozyme (HEL) coupled to beads stimulateda strong proliferative T cell response of lymph node cells fromHEL-primed mice or of specific T cell hybridomas. HEL coupledto beads was presented to the specific T cell hybridomas bysplenocytes or by peritoneal macrophages, but not by lymphomaB cells. Immunization of mice with several different proteinantigens or with a synthetic peptide covalently linked to beadsinduced strong CD4+ T cell responses in the absence of adjuvant.The strong in vivo immunogenicity of proteins coupled to beadsdid not result from a non-specific adjuvant effect of beadssince covalent linkage of the antigen to beads was strictlyrequired to induce T cell responses in the absence of adjuvant.In vivo treatment by carrageenan showed that macrophages arerequired for the in vivo stimulation of T cell responses bythese particulate antigens. Thus, these results demonstratedthe role of phagocytic cells, especially macrophages, for invivo presentation of particulate antigens. These particulateantigens represent an interesting approach for the developmentof new vaccines, and for the in vivo analysis of the role ofvarious antigen presenting cells in T cell activation and differentiation. 相似文献
93.
Five commercially available nitropolyclyclic aromatic hydrocarbons (nitro-PAH), namely, 4-nitrobiphenyl, 2-nitrofluorene, 9-nitroanthracene, 1-nitropyrene, and 2,7-dinitrofluorene, were exposed under restricted sunlight in the open air. The direct-acting mutagenicities of the samples after an exposure of 45 days were measured in order to compare them with those of the original samples in the Ames Salmonella typhimurium bioassay. It was found that the mutagenicities of some nitro-PAH do not change significantly while the mutagenicities of others increase or decrease after exposure. A preliminary study of nitro-PAH reaction products after exposure using GC, GC/MS, and FT-IR is also reported. 相似文献
94.
我院耐甲氧西林金黄色葡萄球菌的耐药性及肠毒素分析 总被引:12,自引:0,他引:12
收集了我院1994年10月至1995年4月金黄色葡萄球菌100株,应用药敏试验筛选MRSA,并检测其对12种抗生素的耐药性,计算MIC50和MIC90,应用乳胶凝集试验法,测定其肠毒素产生率。结果我院总的MRSA阳性率为60%,烧伤科的MRSA的阳性率为67.4%,内科62.5%,骨科44.5%,MRSA耐药性低于50%的有万古霉素(3.3%)去甲万古霉素(5%),丁胺卡那霉素(21.5%)3种, 相似文献
95.
96.
97.
Twenty-one patients, under 6 years of age, with root avulsion of the brachial plexus were treated from 1975 to 1987. Among them, 9 had root avulsion of the upper trunk, 2 root avulsion of the lower trunk with middle trunk broken, and 10 root avulsion of the whole brachial plexus. Follow-up of 16 patients showed excellent results in 2 patients, good in 11, fair in 1 and poor in 2. It is suggested that good results can be obtained if multi-paired nerve transfer is adopted in treatment. We conclude that owing to anatomical and physiological characteristics of the respiratory system in children, it is harmful to perform phrenic nerve transfer concomitantly with intercostal nerve transfer. Advisably, two-stage operation is required, otherwise dyspnea and pneumonia are liable to occur. In addition, the time of the operation could be extended to 4-5 years after injury in children, but best results are obtained if the operation is performed within 1 year.
相似文献
98.
Within a number of physiological preparations, the effects of alcohol and cocaine in combination are reported to be greater
than the effects of either drug given alone. Little has been reported, however, on the behavioral effects of the interaction.
The present study investigated this issue by assessing the effects of cocaine and alcohol (alone and in combination) on schedule-controlled
responding. Specifically, rats were trained to respond on an FR20 schedule for a water reinforcer. They were then administered
cumulative doses of cocaine or alcohol. Following this, subjects were administered ineffective doses of alcohol prior to further
dose-response assessments with cocaine and with ineffective doses of cocaine prior to further dose-response assessments with
alcohol. Cocaine and alcohol alone produced dose-related decreases in responding. Furthermore, the dose-response function
for cocaine was shifted to the left by alcohol and the dose-response function for alcohol was shifted to the left by cocaine.
An isobolographic analysis revealed that the interaction between cocaine and alcohol was additive in nature. The possible
bases for the interaction (e.g., changes in cocaine pharmacokinetics by alcohol and the formation of cocaethylene following
co-administration of cocaine and alcohol) were discussed.
Received: 22 February 1996 / Final version: 23 August 1996 相似文献
99.
目的:研究依那普利(Ena)对豚鼠乳头状肌电生理特性,哇巴因诱发的延迟后除极(DAD)和触发电活动(TA)的直接作用方法与结果,采用标准玻璃微电极技术记录豚鼠乳头状肌动作电位,Ena呈浓度依赖性增加静息膜电位(RP)和动作电位幅度(APA),而对0期最大除极,超射,和动作电位时程无明显影响Ena10μmol.L^-1则可明显抑制哇巴因0.5μmol.L^-1则可明显抑制哇巴因0.5μmol.L^- 相似文献
100.