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1.
流行病学研究的目的在于查明一个社区中某种疾病的分布及其决定因素。麻风的这种研究就是估计其感染和临床疾病的流行率和发生率,监测其传染情况及所采取的各种防治施措的效果。在对麻风菌还不能做体外培养的情况下,血清学便成了研究麻风流行病学的重要方法。为诊断麻风,临床症状学、涂片查菌和组织学检查,便成了常规方法,但它们又都有各自的限度,以致对早期麻风有时很难做出诊断,有些病例要断定它已不活动也同样很难。另一重要问题就是缺少关于亚临床感染的可靠信息,以致此类研究主要是根据临床疾病的发生情况。已有充分的证据, 相似文献
2.
The essential oils from 9 populations of MENTHA LONGIFOLIA (L.) L., ssp. LONGIFOLIA and ssp. PETIOLATA (Boiss.) Kokkini, growing wild in Greece, were investigated by means of GLC and GLC-MS. Piperitone oxide has been found as the main component in the essential oils of both subspecies while carvone only in some individuals of ssp. PETIOLATA (chemotype 2). 相似文献
3.
The capability of integrated flow cytometry to detect, in real time, moving cells in their natural states in vivo is demonstrated in a study of circulating red and white blood cells in lymph and blood flow of rat mesentery. This system combines dual pump-probe photothermal (PT) techniques, such as PT imaging, the PT thermolens method, and PT velocimetry, with high-resolution (up to 0.3 microm), high-speed (up to 1000 fps) transmission digital microscopy (TDM) and fluorescence imaging. All PT techniques are based on irradiation of cells in rat mesenteric microvessels with a spectrally tunable laser pulse (420 to 570 nm, 8 ns, 0.1 to 300 microJ) and on detection of temperature-dependent variations of the refractive index with a second continuous probe laser beam (633 nm, 1.4 mW). We focus on intravital monitoring of the integral PT response from single, moving, unlabeled cells (from 100 to 500 cells in one measurement). Potential in vivo applications of this new optical tool, called PT flow cytometry (PTFC), are discussed, including identification of selected cells with differences in natural absorptive properties and sizes, determination of laser-induced cell damage, estimation of flow velocity, and monitoring of circulating cells labeled with PT probes. 相似文献
4.
Dutta Roy T Simon JL Ricci JL Rekow ED Thompson VP Parsons JR 《Journal of biomedical materials research. Part A》2003,67(4):1228-1237
The current study analyzes the in vivo performance of porous sintered hydroxyapatite (HA) bone repair scaffolds fabricated using the TheriForm solid freeform fabrication process. Porous HA scaffolds with engineered macroscopic channels had a significantly higher percentage of new bone area compared with porous HA scaffolds without channels in a rabbit calvarial defect model at an 8-week time point. An unexpected finding was the unusually large amount of new bone within the base material structure, which contained pores less than 20 microm in size. Compared with composite scaffolds of 80% polylactic-co-glycolic acid and 20% beta-tricalcium phosphate with the same macroscopic architecture as evaluated in a previous study, the porous HA scaffolds with channels had a significantly higher percentage of new bone area. Therefore, the current study indicates that scaffold geometry, as determined by the fabrication process, can enhance the ability of a ceramic material to accelerate healing of calvarial defects. 相似文献
5.
Performance characteristics of a rapid new immunochromatographic test for detection of antibodies to human immunodeficiency virus 总被引:1,自引:0,他引:1
Ribeiro-Rodrigues R Ferreira da Silva Pinto Neto L Cunha CB Cabral VP Dietze R 《Clinical and diagnostic laboratory immunology》2003,10(2):303-307
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers. 相似文献
6.
Simon JL Roy TD Parsons JR Rekow ED Thompson VP Kemnitzer J Ricci JL 《Journal of biomedical materials research. Part A》2003,66(2):275-282
Tight control of pore architecture in porous scaffolds for bone repair is critical for a fully elucidated tissue response. Solid freeform fabrication (SFF) enables construction of scaffolds with tightly controlled pore architecture. Four types of porous scaffolds were constructed using SFF and evaluated in an 8-mm rabbit trephine defect at 8 and 16 weeks (n = 6): a lactide/glycolide (50:50) copolymer scaffold with 20% w/w tri-calcium phosphate and random porous architecture (Group 1); another identical design made from poly(desaminotyrosyl-tyrosine ethyl ester carbonate) [poly(DTE carbonate)], a tyrosine-derived pseudo-polyamino acid (Group 2); and two poly(DTE carbonate) scaffolds containing 500 microm pores separated by 500-microm thick walls, one type with solid walls (Group 3), and one type with microporous walls (Group 4). A commercially available coralline scaffold (Interpore) with a 486-microm average pore size and empty defects were used as controls. There was no significant difference in the overall amount of bone ingrowth in any of the devices, as found by radiographic analysis, but patterns of bone formation matched the morphology of the scaffold. These results suggest that controlled scaffold architecture can be superimposed on biomaterial composition to design and construct scaffolds with improved fill time. 相似文献
7.
8.
Babmindra VP Novozhilova AP Bragina TA Kreĭchman GS Miasnikova OE Zhilinskaia NT Kolla GV 《Morfologii?a (Saint Petersburg, Russia)》1998,114(6):22-27
Using light and electron microscopy structural bases for intracellular, extracellular and integrative regulation of synaptic efficiency and neuron sensitivity were established in rat sensomotor cortex. Intracellular regulation is realized basically through modulation of postsynaptic components of the synapse, while extracellular one is provided by synaptic endings of "recurrent" axons on GABA-ergic relay and interneurons. Integrative regulation is realized by means of concentration of similar axonal terminals in restricted cortical area and arrangement of "neuromediatory" pool. 相似文献
9.
Deletion of decay-accelerating factor (CD55) exacerbates autoimmune disease development in MRL/lpr mice 总被引:7,自引:0,他引:7 下载免费PDF全文
Miwa T Maldonado MA Zhou L Sun X Luo HY Cai D Werth VP Madaio MP Eisenberg RA Song WC 《The American journal of pathology》2002,161(3):1077-1086
Decay-accelerating factor (DAF, CD55) is a glycosylphosphatidylinositol-anchored membrane protein that restricts complement activation on autologous cells. It is also a ligand for CD97, an activation-associated lymphocyte antigen with seven transmembrane domains. It is widely expressed on cells of both the hematopoietic and nonhematopoietic lineages. Although deficiency of DAF on human erythrocytes is associated with the hemolytic anemia syndrome paroxysmal nocturnal hemoglobinuria, the in vivo biology of DAF is still poorly understood. We addressed the in vivo function of DAF in a knockout mouse model and describe here that deletion of DAF exacerbates autoimmune disease development in MRL/lpr mice, a model for human systemic lupus erythematosus. Compared to DAF-sufficient littermate controls, DAF-deficient female MRL/lpr mice developed exacerbated lymphadenopathy and splenomegaly, higher serum anti-chromatin autoantibody levels, and aggravated dermatitis. Consistent with the phenotype of aggravated dermatitis in DAF-deficient mice, Northern and Western blots and immunofluorescence studies showed DAF to be expressed abundantly in the mouse skin, suggesting that it may play a particularly important role in this tissue. Histology and immunostaining demonstrated inflammatory infiltrate and focal C3 deposition in early skin lesions, mostly along the dermal-epidermal junction. These results reveal a protective function of DAF in the development of a systemic autoimmune syndrome and suggest that dysfunction or down-regulation of DAF may contribute to autoimmune disease pathogenesis and manifestation. 相似文献
10.
Razin BV Inzhevatkin EV Nefedova VV Egorova AB Kazbanov VI Nefedov VP 《Bulletin of experimental biology and medicine》2001,131(6):568-569
We studied the effects of cis-dichlorodiammine platinum (II) on different pathways of cell death in cultured Ehrlich ascites carcinoma in vitro and on subsequent growth of transplanted tumor in vivo. One-hour incubation with the cytostatic modulated apoptosis in cell culture. However, exposure of cell culture to a minimal effective concentration of cis-platinum(II)diammine dichloride promoted the growth of transplanted tumor. 相似文献