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31.
Anaerobic, Gram-positive cocci were obtained from chicken feces by direct isolation, which grew on the purines uric acid, xanthine, 6,8-dihydroxypurine, guanine, and hypoxanthine. Adenine and glycine were fermented, but not as readily. Acetate, formate, ammonia, and CO2 were products. The isolated strains were nutritionally non-fastidious, however, they required selenite, molybdate, and tungstate as micronutrients. The cells were spherical and 0.5–0.9 m in diameter. The addition of bile salts enhanced the growth rate in most cases. The organisms proved to be quite resistant to lysis. The guanosine-plus-cytosine (G+C) content of their deoxyribonucleic acid was 33.6 to 34.8 mol%. The peptidoglycan was of the same structure (Gly-Lys-d-Asp) as reported for the anaerobic cocci of Hare group IX. However, the latter strains could only utilize glycine, not purines. Therefore, it is proposed to form a new species, Peptostreptococcus barnesae sp. nov.This paper is dedicated to Prof. Dr. Norbert Pfennig on the occasion of his 60th birthday 相似文献
32.
于国内五个常见白蚁种肠道内共记录到十七个鞭毛虫种。鞭毛虫种群具特异性和稳定性。群落相的变异度反映了宿主白蚁亲缘关系的离散度。异域同种白蚁肠道鞭毛虫群落显示稳定的同一相,同属异种白蚁的鞭毛虫群落部分相同;异科异属或同科异属白蚁的鞭毛虫群落绝然相异。 鉴于传统的生物分类法已明显地显示出其片面性及局限性,为此,人们正试图从其它学科领域,各个不同角度去探索能更客观反映各物种在系统发生上关系的新分类法。迄今,精确定性的生化分类、免疫分类和以群体力对象的定量的数量分类等已倪露头角,从而为以形态描述为主的经典生物分类学注入了新的活力。 本文试图通过对白蚁肠道鞭毛虫群落及种群的研究而借以探讨其在宿主白蚁系统分类研究中的潜在意义。 相似文献
33.
Summary The vacuolar system in the absorptive cells of the goldfish hindgut was studied by rapid freeze-substituted and cytochemical techniques. The apical cytoplasm of the absorptive cells contained two types of vacuoles: endosomes and lysosomes. The former were characterized by an absence of acid phosphatase activity, a dot-like distribution of material at the peripheral rim, the labelling of the inner surface with horseradish peroxidase (HRP), and by frequent connections to cytoplasmic tubules (CT), which were also free of acid phosphatase activity. The latter vacuole was preferentially located in the deeper cytoplasm and was characterized by the presence of acid phosphatase activity, an electron-dense interior matrix, a peripheral electron-lucent region (a halo), and by the detachment of HRP from the inner surface. Connections between CTs and these latter vacuoles were rarely seen. In the deeper cytoplasm, fusion between endosomes and lysosomes was sometimes observed. These results suggest that the vacuoles which are associated with CTs are endosomes, but not lysosomes, and that internalized materials are transported through the endosome-lysosome system to a giant food vacuole in the cell. 相似文献
34.
Taenia solium: cell reactions to the larva (Cysticercus cellulosae) in naturally parasitized, immunized hogs 总被引:1,自引:0,他引:1
In hogs naturally infected with Taenia solium larvae (i.e., Cysticercus cellulosae), we studied the host response induced by antigens obtained from the larvae. Histopathological studies of cysticerci removed after 4 and 8 weeks of immunization showed an intense inflammatory reaction surrounding the larvae. The response was greater in the 8-week specimens. A dense layer of eosinophils was in close contact with the external membrane of the bladder wall and, in several cases, the eosinophils had infiltrated this tegument. Many eosinophils were seen in the spiral canal of larvae. This infiltration by eosinophils increased with time. Preparations from the 8-week samples showed many degenerated and disrupted eosinophils whose granules were found in close contact with the outer membrane of the larval tegument and, in some cases, had entered through the broken surface of this structure. More than 90% of the larvae were found in various stages of degeneration; the rest were completely destroyed and surrounded by a mass of eosinophils. After immunization, peripheral blood eosinophilia increased to 17%, whereas the eosinophilia of the control hog was 4% throughout the study. The larval worms removed from control hogs showed intact structures, with a low degree of infiltration by eosinophils and a discrete inflammatory reaction surrounding the bladder wall of the larvae. 相似文献
35.
Antti Penttilä 《Cell and tissue research》1969,102(2):193-204
Summary Methods for light and electron microscopic comparison of individual argentaffin and argyrophil enterochromaffin cells (EC) in the sheep duodenal mucosa are described. These silver procedures were applied for light microscopy to Epon-embedded sections. The adjacent sections were examined with the electron microscope. The most specific characteristics of the argentaffin and argyrophil EC in electron microscopy are highly osmiophilic cytoplasmic granules. In one cell type these granules are smaller and more roundish than in the another type. These two cell types are stainable both by the argentaffin and argyrophil reactions. No essential difference can be observed in the localization of these elements. It is suggested that both cell types belong to the enterochromaffin system. Both silver methods are also suitable for the light microscopic identification of other intestinal structures in sections adjacent to that sectioned for electron microscopy.This work was supported by a grant from the Yrjö Jahnsson Foundation, Helsinki, Finland.The electron microscopic observations were carried out in the Electron Microscope Laboratory, University of Helsinki. 相似文献
36.
我们选择了几种药性不同的中药,使用各种选择性培养基,对给药组和正常动物组的地鼠肠菌群进行了研究,结果表明,黄芪组与正常动物组比较需氧菌的量有所增加,统计学差异显著(P<0.001)。而其他几味苦寒药(大黄、黄芩、白芍等)对需氧菌的作用不明显。在各类厌氧菌的分离结果中,各给中药组与正常组比较均有明显差异。给药组之间比较,药性相同的组之间没有显著变化,药性不同的组之间变化显著。通过实验我们发现中药对正常地鼠的肠道菌群是有明显影响的,与正常动物组相比及不同药性组间相比各类菌的增长或减少都具有统计学意义。 相似文献
37.
本工作研究了巯基物质在消炎痛引起大鼠胃粘膜损伤中的可能作用。在胃粘膜损伤发生过程中、胃粘膜内非蛋白及蛋白结合的巯基物质含量均无明显降低。虽然半胱胺灌胃(132或264μmol)或皮下注射(132μmol)后均明显抑制消炎痛溃疡的发生,其抑制率分别为82%,92%和75%,但同样具有巯基的半胱氨酸却无保护作用。半胱胺(132μmol)皮下注射可使消炎痛大鼠胃酸分泌抑制46%,而灌胃则无此作用。两种途径给予的半胱胺均不影响胃壁结合粘液的分泌。这些结果表明,胃粘膜内巯基物质似不参与消炎痛的致溃疡过程。半胱胺在此种模型上虽有强烈的细胞保护作用,但似乎不是由于其分子上所带的巯基所致。因此,巯基物质在消炎痛引起的胃粘膜损伤模型上没有细胞保护作用。 相似文献
38.
A preliminary report on the use of transfer factor for treating stage D3 hormone-unresponsive metastatic prostate cancer 总被引:4,自引:0,他引:4
Dr. Giancarlo Pizza Caterina De Vinci Diego Cuzzocrea Domenico Menniti Ernesto Aiello Paolo Maver Giuseppe Corrado Piero Romagnoli Ennio Dragoni Giuseppe LoConte Umberto Riolo Aldopaolo Palareti Paolo Zucchelli Vittorio Fornarola Dimitri Viza 《Biotherapy》1996,9(1-3):123-132
As conventional treatments are unsuccessful, the survival rate of stage D3 prostate cancer patients is poor. Reports have
suggested the existence of humoral and cell-mediated immunity (CMI) against prostate cancer tumour-associated antigens (TAA).
These observations prompted us to treat stage D3 prostate cancer patients with an in vitro produced transfer factor (TF) able
to transfer, in vitro and in vivo, CMI against bladder and prostate TAA. Fifty patients entered this study and received one
intramuscular injection of 2–5 units of specific TF monthly. Follow-up, ranging from 1 to 9 years, showed that complete remission
was achieved in 2 patients, partial remission in 6, and no progression of metastatic disease in 14. The median survival was
126 weeks, higher than the survival rates reported in the literature for patients of the same stage. 相似文献
39.
Prof. Renato Meduri Emilio Campos Lucia Scorolli Caterina De Vinci Giancarlo Pizza Dimitri Viza 《Biotherapy》1996,9(1-3):61-66
Recurrent ocular herpes is an insoluble problem for the clinician. As cellular immunity plays an important role in controlling
herpes relapses, and other studies have shown the efficacy of HSV-specific transfer factor (TF) for the treatment of herpes
patients, an open clinical trial was undertaken in 134 patients (71 keratitis, 29 kerato-uveitis, 34 uveitis) suffering from
recurrent ocular herpetic infections. The mean duration of the treatment was 358 days, and the entire follow-up period 189121
before, and 64062 days after TF treatment. The cell-mediated immune response to the viral antigens, evaluated by the lymphocyte
stimulation test (LST) and the leucocyte migration test (LMT) (P<0.001), was significantly increased by the TF treatment.
The total number of relapses was decreased significantly during/after TF treatment, dropping from 832 before, to 89 after
treatment, whereas the cumulative relapse index (RI) dropped, during the same period, from 13.2 to 4.17 (P<0.0001). No side
effects were observed. It is concluded that patients with relapsing ocular herpes can benefit from treatment with HSV-specific
TF. 相似文献
40.
Using a blood cell separator, lymphocytes were collected from otherwise healthy convalescents suffering from herpetic infections.
A specific anti-herpes dialysate (AH-DLE) was prepared from the lymphocytes, using standard procedures. Patients with recurrent
herpetic infections were treated with a single dose of the dialysate, at the initial signs of herpetic infection (group A),
with two doses (group B) or with three doses (group C). A total number of 37 patients (29 women, 8 men, age range 15–73 years)
were treated. No improvement was observed in 7 patients (18.9%), whilst 7 patients did not manifest any exacerbation of their
herpetic infection in the course of the one-year follow-up. The remaining 62.2% of the patients showed a marked improvement:
decrease of the frequency and/or duration or relapses. Before AH-DLE administration, the mean number of herpes relapses in
this group of patients was 12 p.a.. After therapy, the number of relapses decreased to 3.5 p.a.. No statistically significant
difference was observed between groups A and B. The least favourable results were registered in group C. However, this group
included 6 female patients extremely resistant to the previously therapeutic attempts, including inosiplex, non-specific DLE
or acyclovir. Thus, even in this group, the therapy was successful in 50% of the patients. 相似文献