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71.
Fine needle aspiration cytology in the diagnosis of sinuses and ulcers of the body surface (skin and tongue) 总被引:1,自引:0,他引:1
Both fine needle aspiration (FNA) and conventional scraping were used to obtain cytodiagnostic samples from ulcers and sinuses of the skin (18 cases) and tongue (3 cases). These included 14 cases of tuberculosis, 5 squamous-cell carcinomas and 2 cases of nonspecific infection. The FNA smears contained characteristic tuberculous granulomas or epithelioid cells in 10 of the 14 tuberculosis cases and ample diagnostic material in 4 of the 5 carcinoma cases; in contrast the scraping smears predominantly contained necrotic material on which a diagnosis was not possible. Of the 19 cases of tuberculosis and malignancy, 12 were diagnosed only by FNA, 6 were diagnosed by both methods and the FNA sample was negative while the scrape was positive in 1 case. Hence, the diagnosis was made in 18 of 19 by FNA cytology, but in only 7 of 19 cases by scraping cytology, strongly indicating the diagnostic superiority of the former in diagnosing many lesions of the body surface. 相似文献
72.
Influence of complement C5 and V beta T cell receptor mutations on susceptibility to collagen-induced arthritis in mice 总被引:8,自引:0,他引:8
S Banerjee G D Anderson H S Luthra C S David 《Journal of immunology (Baltimore, Md. : 1950)》1989,142(7):2237-2243
SWR/J mice are resistant to collagen-induced arthritis (CIA) despite having a susceptible H-2q haplotype. We have earlier demonstrated the possible role of the V beta TCR mutation of SWR in the resistance to CIA. To investigate the influence of the C5 deficiency of SWR in this resistance, crosses were made between SWR and A/J (C5 deficient, TCRwild, H-2a), and between SWR and C3H.A (C5 sufficient, TCRwild, H-2a). Upon immunization with bovine type II collagen in adjuvant, there was a similar incidence and severity of arthritis in H-2q-bearing mice in the back-crosses A x (SWR x A) ad C3H.A x (SWR x C3H.A). The absence of hemolytic complement was confirmed in the arthritic A x (SWR x A) back-cross mice by standard SRBC hemolytic assays. In addition C57L (H-2b) mice, which were C5 sufficient but had a V beta TCR deletion mutation similar to SWR, could not complement for CIA susceptibility in H-2q-bearing C57L x (SWR x C57L) back-crosses and in (C57L x SWR)F2 hybrids. These studies show that complement C5 does not play a significant role in CIA susceptibility, and further implicate the V beta TCR mutation in the resistance to CIA in SWR mice. 相似文献
73.
74.
Anand A Luthra A Dunham-Ems S Caimano MJ Karanian C LeDoyt M Cruz AR Salazar JC Radolf JD 《Journal of bacteriology》2012,194(9):2321-2333
Identification of Treponema pallidum rare outer membrane proteins (OMPs) has been a longstanding objective of syphilis researchers. We recently developed a consensus computational framework that employs a battery of cellular localization and topological prediction tools to generate ranked clusters of candidate rare OMPs (D. L. Cox et al., Infect. Immun. 78:5178-5194, 2010). TP0117/TP0131 (TprC/D), a member of the T. pallidum repeat (Tpr) family, was a highly ranked candidate. Circular dichroism, heat modifiability by SDS-PAGE, Triton X-114 phase partitioning, and liposome incorporation confirmed that full-length, recombinant TprC (TprC(Fl)) forms a β-barrel capable of integrating into lipid bilayers. Moreover, TprC(Fl) increased efflux of terbium-dipicolinic acid complex from large unilamellar vesicles and migrated as a trimer by blue-native PAGE. We found that in T. pallidum, TprC is heat modifiable, trimeric, expressed in low abundance, and, based on proteinase K accessibility and opsonophagocytosis assays, surface exposed. From these collective data, we conclude that TprC is a bona fide rare OMP as well as a functional ortholog of Escherichia coli OmpF. We also discovered that TprC has a bipartite architecture consisting of a soluble N-terminal portion (TprC(N)), presumably periplasmic and bound directly or indirectly to peptidoglycan, and a C-terminal β-barrel (TprC(C)). Syphilitic rabbits generate antibodies exclusively against TprC(C), while secondary syphilis patients fail to mount a detectable antibody response against either domain. The syphilis spirochete appears to have resolved a fundamental dilemma arising from its extracellular lifestyle, namely, how to enhance OM permeability without increasing its vulnerability to the antibody-mediated defenses of its natural human host. 相似文献
75.
Zoe Inman Helen Martin SA Paul Chubb 《The Clinical biochemist. Reviews / Australian Association of Clinical Biochemists》2009,30(3):141-151
Background
The lack of guidelines on reporting standards for protein electrophoresis may have led to significant differences in reports from different laboratories.Objective
To determine the extent of variation in reporting of protein electrophoresis results in Australia and New Zealand.Method
Questionnaires were distributed to laboratories throughout Australia and New Zealand asking about protein electrophoresis practices and reporting.Results
Extensive variation was found in the following reporting practices: (a) units for urine Bence Jones protein (BJP); (b) reporting absence of a paraprotein rather than a normal pattern; (c) numerical reporting of all protein fractions or only the paraprotein; (d) warning of possible inaccuracy in the serum immunoglobulin result of the paraprotein type; (e) co-migration of a paraprotein with a normal serum protein; (f) use of a confirmatory test when a known paraprotein is no longer detectable.Conclusions
A working party should be established to make recommendations on the reporting of protein electrophoresis. Implementation of such recommendations should reduce both report variation between laboratories and the risk of misinterpretation of reports. 相似文献76.
THAÍSA SALA MICHELAN SIDINEI MAGELA THOMAZ ROGER PAULO MORMUL PRISCILLA CARVALHO 《Freshwater Biology》2010,55(6):1315-1326
1. The issue of freshwater species being threatened by invasion has become central in conservation biology because inland waters exhibit the highest species richness per unit area, but apparently have the highest extinctions rates on the planet. 2. In this article, we evaluated the effects of an exotic, invasive aquatic grass (Urochloa subquadripara– tropical signalgrass) on the diversity and assemblage composition of native macrophytes in four Neotropical water bodies (two reservoirs and two lakes). Species cover was assessed in quadrats, and plant biomass was measured in further quadrats, located in sites where tropical signalgrass dominated (D quadrats) and sites where it was not dominant or entirely absent (ND quadrats). The effects of tropical signalgrass on macrophyte species richness, Shannon diversity and number of macrophyte life forms (a surrogate of functional richness) were assessed through regressions, and composition was assessed with a DCA. The effects of tropical signalgrass biomass on the likelihood of occurrence of specific macrophyte life forms were assessed through logistic regression. 3. Tropical signalgrass had a negative effect on macrophyte richness and Shannon and functional diversity, and also influenced assemblage composition. Emergent, rooted with floating stems and rooted submersed species were negatively affected by tropical signalgrass, while the occurrence of free‐floating species was positively affected. 4. Our results suggest that competition with emergent species and reduction of underwater radiation, which reduces the number of submersed species, counteract facilitation of free‐floating species, contributing to a decrease in plant diversity. In addition, homogenisation of plant assemblages shows that tropical signalgrass reduces the beta diversity in the macrophyte community. 5. Although our results were obtained at fine spatial scales, they are cause for concern because macrophytes are an important part of freshwater diversity. 相似文献
77.
目的对长爪沙鼠线粒体DNA控制区全序列进行测定,并对其进行鉴定及进化分析。方法根据长爪沙鼠已知基因序列设计引物,采用PCR产物测序法,对所得的片段进行测序鉴定。结合已公布啮齿类动物D-loop区序列,分析其碱基组成、遗传距离、并基于最小进化法和UPGMA法构建系统进化树。结果获得长爪沙鼠D-loop区序列,其与家鼠、小家鼠和仓鼠平均同源性为58%;碱基组成分析显示,长爪沙鼠与啮齿类动物有相似的碱基组成和碱基偏离,其A-skew和G-skew分别为0.0047和-0.28。进化分析结果显示,长爪沙鼠与家鼠(0.35)、黑家鼠(0.38)和仓鼠(0.39)具有较近的遗传距离,其分化顺序为跳鼠、蔗鼠、长爪沙鼠、仓鼠、家鼠和小家鼠。结论本研究获得长爪沙鼠D-loop区全序列,确定了长爪沙鼠与仓鼠、家鼠、小家鼠及其它啮齿动物的进化关系,为长爪沙鼠进化研究、线粒体的结构和功能研究奠定基础。 相似文献
78.
Background
Hyperplasia of usual type (HUT) is a common proliferative lesion associated with a slight elevated risk for subsequent development of breast cancer. Cell cycle-related proteins would be helpful to determine the putative role of these markers in the process of mammary carcinogenesis. The aim of this study was to analyze the expression of cell cycle related proteins in HUT of breast specimens of patients with and without breast cancer, and compare this expression with areas of invasive carcinomas. 相似文献79.
OBJECTIVE--To assess the efficacy of visual screening for cervical cancer in the maternal and child health setting. DESIGN--Clinical and cytological screening. SETTING--Maternal and child health centres, Delhi. SUBJECTS--44,970 women attending the centres from May 1988 to March 1991. RESULTS--238 cancers in early stages (0-IIa) were detected cytologically and proved through biopsy. Prevalence of cancer in women defined as high risk through examination by speculum was 29/1000 as compared to 1.53/1000 among women with a normal looking cervix. Though only 11.4% women belonged to the high risk category, 63% had early stage cancer. If all women with bleeding symptoms were included in the high risk category, the yield of cancer would be 71.4% (170/238) by referring only 15.6% of women attending maternal and child health centres for further evaluation through cytology or colposcopy. CONCLUSION--Though visual screening is a suboptimal strategy in comparison to the cytological screening, it may be useful where there is a heavy load of prevalent cancer and where cytological screening may not be available for years to come. 相似文献
80.
ROGER HÄRDLING ÅSA BORG DAVID CARRASCO MARI KATVALA ARJA KAITALA 《Ecological Entomology》2007,32(5):575-577