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81.
The relationship between cytotoxicity and prognostically significant histologic changes in lymph nodes from patients with cancer of the breast.
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Axillary lymph nodes obtained from 37 patients with cancer of the breast were used in a microcytotoxicity assay against a human mammary cancer cell line, ALAB. Cell suspensions made from 60 individual lymph nodes and 51 lymph node pools were tested. Each lymph node was graded for the extent of the histologic changes of sinus histiocytosis (SH), paracortical hyperplasia (PCH), and germinal center hyperplasia (GCH). High levels of cytotoxicity correlated significantly with the presence of SH and PCH. When multiple lymph nodes of individual patients were pooled and tested, a high intensity of GCH correlated with a low degree of cytototoxicity. The cytotoxic activity of pooled lymph nodes from different axillary regions was studied in 20 patients. In 7 of these patients, low axillary lymph node cells were more cytotoxic than high axillary node cells. The reverse was found for 7 patients, and there was no difference in cytotoxicity between axillary regions in 6. Cytotoxic lymph node pools had high SH and low GCH whether they were obtained from the low or high region. Noncytotoxic lymph node pools from the high axillary region had a low intensity of all three histologic reactions. In contrast, noncytotoxic lymph node pools from the low axillary regions had high intensities of SH, PCH, and GCH. These results suggest that germinal center hyperplasia in the lymph nodes nearest an advancing tumor is associated with a local suppression of cytotoxic cell activity. 相似文献
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86.
Green Steven; Fishel Simon; Hall Jenny; Hunter Alison; Fleming Steven; Hobson Geoffrey; Roe Heather; Dowell Ken; Thornton Simon; Klentzeris Lucas 《Human reproduction (Oxford, England)》1995,10(6):1430-1434
Utilizing real-time computer image analysis, individual spermatozoawere selected using microaspiration. Selection criteria werebased on potential hyperactivation motility characteristics;the amplitude of lateral head displacement >7.5 µm,curvilinear velocity >70 µm/s and linearity of <30%.For this pilot study, 16 patients (eight in each group) wererecruited. Using subzonal insemination (SUZI), up to five (mean= 4.4 ± 0.3) spermatozoa selected using computer-imagesperm selection (CISS) were microinjected, or up to 15 (mean= 12.8 ± 1.3 SD) unselected spermatozoa. In the groupwhich utilized CISS, 28 out of 49 (57%) oocytes were fertilizedcompared with 13 out of 52 (25%) utilizing conventional SUZI(P < 0.04); polyspermy was 20% (n = 10) and 2% (n = 1) respectively.CISS with SUZI showed increased efficiency in achieving fertilizationand is a novel approach to studying individual sperm functionin a sperm egg bioassay where gamete ratios are close to unity. 相似文献
87.
F Ito E F Hunter R W George B L Swisher S A Larsen 《Journal of clinical microbiology》1991,29(3):444-448
To date, tissue sections prepared from Formalin-fixed tissues have not been successfully stained with Treponema pallidum subspecies-specific antibody in a direct fluorescent-antibody assay. While current methods stain T. pallidum, they do not distinguish T. pallidum from other spirochetes such as Borrelia burgdorferi (E. F. Hunter, P. W. Greer, B. L. Swisher, A. R. Simons, C. E. Farshy, J. A. Crawford, and K. R. Sulzer, Arch. Pathol. Lab. Med. 108:878-880, 1984). Because trypsin pretreatment of tissue sections has enhanced other immunofluorescent-antibody (IFA) applications, we compared the use of the trypsin digestion method with the current 1% ammonium hydroxide (NH4OH) method as a means to obtain specific staining of T. pallidum in tissues by both direct and indirect IFA techniques. Pretreated T. pallidum-infected tissues sections from rabbits, hamsters, and humans were quantitatively examined with the direct fluorescent-antibody-T. pallidum test conjugate absorbed with Treponema phagedenis, the Reiter treponeme. For indirect staining, a serum specimen from a patients with syphilis absorbed by affinity chromatography with T. phagedenis was used as the primary reagent, and a fluorescein isothiocyanate-labeled rabbit anti-human globulin was used as the secondary reagent. Serum specificity was established first by examining antigen smears of T. pallidum subsp. pallidum, T. pallidum subsp. pertenue, B. burgdorferi, T. phagedenis, and Treponema denticola MRB and then by examining tissues infected with these pathogens plus those infected with four Leptospira serovars. When we stained tissue using the direct IFA method that is currently a standard method for the examination of chancre smears, we found it to be unsuitable for use with tissue. Trypsin digestion did not offer an improvement over the NH4OH pretreatment method in the specific identification of T. pallidum by direct IFA. However, specific identification of T. pallidum in tissue sections was obtained by the indirect IFA technique after either trypsin or NH4OH pretreatment. 相似文献
88.
Use of modified resistogram to type Candida albicans isolated from cases of vaginitis and from faeces in the same geographical area. 总被引:1,自引:0,他引:1
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Ninety strains of Candida albicans were isolated from vaginal swabs taken by general practitioners from cases of vaginal candidosis. One hundred and nine strains were also isolated from 300 specimens of faeces received from outpatients living in the same geographical area. These strains were typed using a modification of the resistotyping method. We were unable to find any significant differences between the two populations of strains. This suggests that no particular resistotype has an increased ability to cause vaginitis. 相似文献
89.
Scrapie is a transmissible spongiform encephalopathy in which there is an accumulation of the abnormal form of the prion protein, PrPsc, in the lymphoreticular system and nervous system. There is a particular accumulation of PrPsc on follicular dendritic cells within the germinal centre of B-cell follicles. Because accumulation of PrPsc in the nervous system leads to neuronal cell loss we have examined PrPsc accumulation in the prescapular and mesenteric lymph nodes in relation to lymph node architecture of scrapie-challenged sheep. We demonstrate that an accumulation of PrPsc in the lymph node fails to result in gross defects in the microanatomy and phenotype of T- and B-cell areas in the lymph nodes. 相似文献
90.
Chemical synthesis and serology of disaccharides and trisaccharides of phenolic glycolipid antigens from the leprosy bacillus and preparation of a disaccharide protein conjugate for serodiagnosis of leprosy. 总被引:9,自引:3,他引:9
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We examined the structural requirements within the species-specific 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- alpha-L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose unit of the phenolic glycolipid I antigen of Mycobacterium leprae for binding to anti-glycolipid immunoglobulin M from human leprosy sera. We used chemically defined, partially deglycosylated fragments of phenolic glycolipid I, two other minor M. leprae-specific phenolic glycolipids (those containing 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-L-rhamnopyranose and 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-3-O-methyl-alpha- L-rhamnopyranosyl-(1 leads to 2)-3-O-methyl-alpha-rhamnopyranose units), and phenolic glycolipids from other mycobacteria. Additionally, the trisaccharide of phenolic glycolipid I, the 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2, 3-di-O-methyl-alpha-L-rhamnopyranose, the 6-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose, and the beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl-alpha- L-rhamnopyranose disaccharides were synthesized and characterized, and their activities were examined. Only the phenolic glycolipids containing 3,6-di-O-methyl-beta-D-glucopyranosyl at the nonreducing terminus were efficient in binding the anti-glycolipid immunoglobulin M, and the 3,6-di-O-methyl-beta-D-glucopyranosyl-containing di- and trisaccharides were the most effective in inhibiting this binding. Thus, the 3,6-di-O-methyl-beta-D-glucopyranosyl substituent was recognized as the primary antigen determinant in phenolic glycolipid I. With this information, bovine serum albumin containing reductively aminated 3,6-di-O-methyl-beta-D-glucopyranosyl-(1 leads to 4)-2,3-di-O-methyl- L-rhamnose was prepared and shown to be highly active in the serodiagnosis of leprosy. 相似文献