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81.
Summary A total of 824 chain-saw operators who were employed in felling trees in the forestry industry were exposed to local vibration, which produced peripheral blood-flow disorders and lesions in the joints and hand bones. In the last 10 years, they have undergone 24-day balneoclimatic treatment at the Kolobrzeg Health Resort. It was found that a stay in the spa and certain balneological treatments exert a favorable effect on the peripheral blood-flow disorders produced by the local vibration of chain saws. The symptoms (chills and numbing of the fingers, etc.) disappeared in nearly 40% of these workers. An improvement in the objective indices of the peripheral circulation (thermographic and plethysmographic tests) was observed in about 90% of patients treated with brine baths combined with underwater vibratory massage (rotatory) or brine baths alone. The brine bath and vibratory massage have a direct beneficial influence on the peripheral blood flow of pectoral limbs. 相似文献
82.
83.
An electron-cytochemical investigation was made of oxidation of 3,3-diaminobenzidine (DAB) in the brain of rats and man at different times after death. The oxidation product of DAB was localized in the mitochondria, lipofuscin granules, and erythrocytes. Oxidation of DAB by rat and human brain mitochondria was shown to be only very slightly depressed even 2 days after death.Laboratory of Experimental Pathology and Pathomorphology of the Brain, Institute of Psychiatry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. V. Snezhnevskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 6, pp. 757–759, June, 1976. 相似文献
84.
Gerald R. Buzzell Armando Menndez-Pelez Roger A. Hoffman Carmen Rodríguez Isaac Antolin 《Anatomical record (Hoboken, N.J. : 2007)》1994,240(1):52-58
Background: The porphyrin concentrations of the Harderian glands of Syrian hamsters show marked sexual differences, with male levels being much lower than those of females. Porphyrinogenesis is inhibited by androgens, so orchidectomy leads to elevated male porphyrin concentrations; however, a number of other procedures (some of which also lower androgen levels) prevent this. We studied the effects of short-day photoperiods and melatonin on Harderian porphyrin concentrations. Methods: Intact, castrated, or pinealectomized hamsters of both sexes were exposed to long-day or short-day photoperiods. Intact or castrated hamsters were given melatonin injections in the morning or the afternoon, or were given beeswax pellets containing melatonin. After a variable period, Harderian glands were dissected and porphyrins were measured. Results: Prolonged short-day exposure (13 weeks) led to increased Harderian porphyrin concentrations and this rise was prevented by pinealectomy. The rise in Harderian porphyrins following short-day exposure was small, compared with that following castration. Short-day photoperiods also prevented the rise in porphyrin levels associated with castration and this effect was prevented by removal of the pineal. Melatonin injections, whether given in the morning or in the afternoon, had no effect on Harderian porphyrin concentration of castrated male hamsters. Continuous release melatonin pellets reduced the postcastrational rise in porphyrin levels in one experiment, while having no effect in another. In female hamster, neither short photoperiods nor melatonin pellets influenced Harderian porphyrin concentrations. Conclusions: These results suggested that a factor from the pineal gland helps maintain the low levels of porphyrin which are characteristic of male Harderian glands, despite the decrease in androgen levels which typically results from exposure to short days. Morning and afternoon injections of melatonin and continuous release melatonin pellets failed to resolve the question of whether this pineal factor is melatonin. Our results demonstrated that low male and high female porphyrin levels are maintained in Syrian hamsters, despite seasonal variations in the hormonal milieu, suggesting that these sexual differences are important for the (still unestablished) function of the Harderian glands in this species. © 1994 Wiley-Liss, Inc. 相似文献
85.
Primary malignant melanoma of the esophagus 总被引:2,自引:0,他引:2
Dr. Ernst -Dietrich Kreuser 《Virchows Archiv : an international journal of pathology》1979,385(1):49-59
Summary A case of primary malignant melanoma of the esophagus in a 74-year-old male is described. There was a diffuse pigmentation of the lower third of the esophagus macroscopically. Sections from this area revealed melanocytes in the basal layer of the epithelium. This melanosis was not caused by malignant melanoma cells, but obviously by preexisting ectopic and pigmented melanocytes a condition for which the term esophageal melanocytosis is proposed. It is suggested that esophageal melanocytosis as well as the presence of junctional changes may determine the primary nature of malignant melanoma of the esophagus. Furthermore, in order to outline the histologic criteria and the pathological features of primary esophageal melanomas, 64 cases have been reviewed. 相似文献
86.
Lorenzo Moretta Maria Cristina Mingari Daniela Pende Cristina Bottino Roberto Biassoni Alessandro Moretta 《Journal of clinical immunology》1996,16(5):243-253
Natural Killer cells are likely to play an important role in the host defenses because they kill virally infected or tumor cells but spare normal self-cells. The molecular mechanism that explains why NK cells do not kill indiscriminately has recently been elucidated. It is due to several specialized receptors that recognize major histocompatibility complex (MHC) class I molecules expressed on normal cells. The lack of expression of one or more HLA class I alleles leads to NK-mediated target cell lysis. Different types of receptors specific for groups of HLA-C, HLA-B, and, very recently, HLA-A alleles have been identified. While in most instances, they function as inhibitory receptors, an activatory form of the HLA-C-specific receptors has been identified in some donors. Molecular cloning of HLA-C-, HLA-B- or HLA-A-specific receptors has revealed new members of the immunoglobulin superfamily with two or three Ig-like domains, respectively, in their extracellular portion. While the inhibitory form is characterized by a long cytoplasmic tail associated with a non-polar transmembrane portion, the activatory one has a short tail asociated with a Lys-containing transmembrane portion. Thus, these human NK receptors are different from the murine Ly49, that is a type II transmembrane protein characterized by a C-type lectin domain. A subset of activated T lymphocytes expresses NK-type class I-specific receptors. These receptors exert an inhibiting activity on T cell receptor-mediated functions and may provide an important mechanism of downregulation of T cell responses. 相似文献
87.
Nora Ostrzega 《Diagnostic cytopathology》1993,9(4):457-460
The cytologic findings of juvenile papillomatosis (JP) have been rarely described. The clinical and cytologic findings were suggestive of a fibroadenoma, but due to the presence of 2 cc of clear fluid during the aspiration, fibrocystic change was in the differential diagnosis. Operation and subsequent examination of the mass identified a case of JP (so-called Swiss cheese disease of the breast). Because JP is a marker for breast carcinoma for the patients' families, and the patients may themselves be at increase risk for malignancy, it is important that this entity be considered in the differential diagnosis. The observations in this case indicate that it is difficult to diagnose JP only by cytology, but the combination of clinical findings—a well-circumscribed mass in a young patient with cystic fluid, but with a residual mass after aspiration due to the multicystic nature of JP—with the cytologic findings—sheets of hyperplatic breast epithelium with areas resembling fibroadenoma, macrophages, and apocrine cells—that appear to be sufficiently characteristic to suggest the diagnosis of JP. 相似文献
88.
Douglas M. Strong John R. Ortaldo Franco Pandolfi Annette Maluish Ronald B. Herberman 《Journal of clinical immunology》1982,2(3):214-221
Cryopreserved human peripheral blood mononuclear cells (PBMC) were tested for natural killer (NK) and antibody-dependent cellular cytotoxicity (ADCC) and for high-affinity (29°C) and total (4°C) rosette formation with sheep erythrocytes. PBMC produced variable NK activity following freezing and thawing, but consistently reacted well in ADCC. A significant correlation was found between low NK activity and a decreased percentage of low-affinity rosette-forming cells. On the contrary, the number of large granular lymphocytes (LGL), among which NK cells are restricted, and the reactivity with the monoclonal antibody OKT10, which recognizes the majority of LGL in the peripheral blood, were not significantly altered by cryopreservation. Cryopreserved cells proved to be excellent controls for determining the day-to-day variability of the NK assay and for selecting optimum conditions for this test in the clinical immunology laboratory. 相似文献
89.
Jean E. Merrill 《Journal of clinical immunology》1983,3(1):42-50
Though purported to be identical cells (or in identical populations of cells), the natural killer (NK) cell mediating spontaneous natural cytotoxicity and the killer (K) cell mediating antibody-dependent cellular cytotoxicity (ADCC) may not be totally identical, at least in susceptibility to regulation by the immunomodulators prostaglandin E1 (PGE1) and interferon (IFN). We demonstrate here that NK cells are always enhanced by IFN, while K cells are inhibited from binding targets, resulting in fewer effectors at optimal concentrations of antibody. Only at 10- to 100-fold suboptimal concentrations of antibody is ADCC activity enhanced. As measured by magnitude of inhibition and dose-response titration, ADCC activity is less sensitive to the effects of PGE1 than is NK activity in the51Cr release assay and single-cell assay. After overnight incubation with or without PGE1, whatever sensitivity ADCC activity had to PGE1 is lost. However, NK cells incubated in the presence of PGE1 overnight are still sensitive to inhibition. Indomethacin boosts NK activity without having any effect on ADCC activity. Finally, NK activity is substantially reduced by overnight incubation of cells at room temperature, which has no effect on K cells. 相似文献
90.
西部开发中的虫媒病传播问题 总被引:1,自引:1,他引:1
陆宝麟 《寄生虫与医学昆虫学报》2003,10(4):212-217
西部开发地区存在许多虫媒病 ,即昆虫和蜱螨传播的疾病 ,为了保障开发人群的健康 ,首先需要对这些疾病的传播 ,特别是有些疾病的自然疫源地或流行区有所了解。本文列述了 13种虫媒病及其在这个地区的分布 ,对其中值得我们更重视的 4类重要疾病 ,包括鼠疫、莱姆病、疟疾和登革热的病原体传播媒介或有的贮存宿主以及重要性等作了扼要的介绍。本文并提出了这类疾病在开发中和开发后可能产生的危害性 ,以及防止或减少它们危害的建议。作者认为从开发地区的长远利益出发 ,应该重视开发中自然环境改变对上述虫媒病传播影响的研究 相似文献