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21.
R. Condon W. P. Colquhoun P. Knauth R. Plett B. Neidhart D. DeVol S. Eickhoff J. Rutenfranz 《International archives of occupational and environmental health》1988,61(1-2):39-49
Summary Daily diary records of sleep and activity, and 4-h measurements of body temperature, performance and subjective alertness were collected on board ship from 15 watchkeepers on the 4-on/8-off system, and from 28 dayworkers, on both westward and eastward transatlantic voyages. The data from a balanced sample of the subjects were analysed over selected 8-d periods of the voyages where four or five time zones were crossed. During these periods the average amount of daily sleep obtained by dayworkers on the eastward voyage was more than 1 h less than that on the westward voyage, and its quality was rated lower. Watchkeepers' main sleep was also shorter when travelling eastward, but this reduction was partially compensated for by a slightly longer secondary sleep. With the exception of subjective alertness on the eastward voyage, the basic phase of the circadian rhythms in the measured variables adjusted appropriately to the clock changes associated with the time zone crossings. The normal shape of the average daily curves was, however, altered differentially in the two directions of travel; as a result, morning levels of all variables were lower on the eastward voyage than on the westward, but evening levels were higher. These distortions of rhythm waveforms, which probably arose from a combination of endogenous and exogenous factors, add another dimension to the basic problem caused by the effects of circadian rhythms on operational efficiency in the shipboard situation. This problem can only be solved by the development of alternative watchkeeping systems which take full account of these rhythms.Partly supported by a grant from the West German Ministry for Technology and Research, Project Schiff der Zukunft, Part ET 83b 相似文献
22.
猪卵透明带单克隆抗体的研制 总被引:1,自引:1,他引:0
用热溶猪卵透明带抗原免疫BALB/C 小鼠,取其脾细胞和SP2/O 细胞融合产生的杂交瘤。用间接免疫荧光和ELISA 方法筛选,经四次克隆化后,获得三株分泌猪卵透明带单克隆抗体杂交瘤细胞株(LPD_8,LPC_4,LPD_2)。通过间接免疫荧光试验,其中二株单克隆抗体(LPD_8,LPC_4)与人卵透明带有交叉反应。但它们在猪与人卵透明带上呈现的荧光部位有明显的不同,LPD_8位于整个透明带上,而LPC_4只见于透明带外层。LPD_2荧光位于透明带内层且与人卵无交叉反应。我们认为这种差别是由于抗原决定簇的不同所致。 相似文献
23.
Lymphotoxin but not tumor necrosis factor functions to maintain splenic architecture and humoral responsiveness in adult mice 总被引:1,自引:0,他引:1
Fabienne Mackay Gerard R. Majeau Pornsri Lawton Paula S. Hochman Jeffrey L. Browning 《European journal of immunology》1997,27(8):2033-2042
To compare the function of the tumor necrosis factor (TNF) and lymphotoxin (LT)α/β systems in the mature immune system, these two pathways were blocked with soluble receptor-immunoglobulin (R-Ig) fusion proteins in normal adult mice. Inhibition of LTα/β signaling using LTβR-Ig or a blocking monoclonal antibody against murine LTβ had profound effects. The spleen lacked discrete B cell follicles and the marginal zone was altered. Less marked changes were detected in lymph nodes. LTα/β inhibition also prevented germinal center formation in the spleen and impaired Ig production in response to sheep red blood cells (SRBC) immunization. These results show that the LTα/β system is required for the maintenance of splenic architecture and normal immune responses, and not simply for the development of peripheral immune organs during ontogeny. In contrast, inhibition of the TNF/LTα pathway with TNF-R55-Ig did not affect the splenic architecture or the anti-SRBC response. Splenic defects and impaired antibody responses are seen in TNF-deficient mice, suggesting that TNF is important during development. Therefore relative to TNF, the LT system has the dominant influence on splenic organization and anti-SRBC Ig formation in the adult mouse. 相似文献
24.
25.
API2-MALT1融合基因变异体在粘膜相关淋巴组织结外边缘区B细胞淋巴瘤中的分布及凋亡的关系 总被引:2,自引:0,他引:2
目的探讨API2-MALT1融合基因变异体在粘膜相关淋巴组织结外边缘区B细胞淋巴瘤(extranodal marginal zone B—cell lymphoma of mucosa—associated lymphoid tissue,MALT)中的分布特点及其转录与肿瘤凋亡的关系。方法将逆转录-聚合酶链反应和巢式聚合酶链式反应结合,检测62例不同部位MALT淋巴瘤中API2-MALT1融合基因的多种变异体;通过TdT介导脱氧核苷酸缺口末端标记技术进行肿瘤细胞的原位凋亡检测;通过逆转录-聚合酶链反应和免疫组化染色检测API2的mRNA和蛋白水平。结果62例MALT淋巴瘤中28例检出API2-MALT1融合基因(45.16%),为变异体A1446-M1123或A1446-M814,但未检出A1446-M541和A1446-M1150。A1446-M1123(18/28)的检出明显多于A1446-M814(10/28)。融和基因转录在甲状腺MALT淋巴瘤中检出最低,在其它部位的分布无差异。在API2-MALT1^ 组(API2-MALT1mRNA表达阳性组)肿瘤凋亡水平明显高于API2-MALT1^-组(API2-MALT1mRNA表达阴性组),API2的mRNA和蛋白水平低于阴性组。A1446-M1123^ 与A1446-M814^ 病例之间凋亡和API2的变化无差异。结论MALT淋巴瘤中t(11;18)(q21;q21)的发生有部位差异,A1446-M1123可能是中国人MALT淋巴瘤中API2-MALT1融合基因变异体的主要类型。API2-MALT1融合基因转录与MALT淋巴瘤的凋亡水平和API2的变化有关。 相似文献
26.
成年大鼠去皮层血管引起前脑室下区祖细胞增殖迁移并形成迁移路至损伤部位(一)祖细胞增殖迁移的部位在背外侧脑室下区 总被引:3,自引:1,他引:3
成年哺乳动物脑室下区(SVZ)富有神经干细胞、神经细胞祖细胞和胶质细胞祖细胞,它们能生成新的神经细胞、星状胶质细胞和少突胶质细胞。SVZ中的神经细胞祖细胞能形成切线形式的嘴侧迁移流(RMS)到嗅球,在嗅球分化成成熟的中间神经元。近年来证明成年动物实验性脑损伤和变性疾病都能引起SVZ细胞增生并能向非嗅球区迁移。本研究将成年大鼠一侧大脑皮层血管去除,15d和30d后取前脑作冠状及矢状连续切片,用BrdU和PCNA抗体显示前脑室下区正在分裂的细胞;用Tuj1抗体显示神经元祖细胞;用GFAP和vimentin抗体显示胶质细胞祖细胞。结果证明去除一侧皮层血管引起术侧及其对侧的背外侧脑室下区(dl-SVZ)的上述免疫反应阳性细胞明显增多,并向胼胝体迁移,在胼胝体内形成放射形式迁移路至损伤部位。本研究表明背外侧脑室下区的范围应包括背外侧角、外侧伸展和侧脑室上壁的SVZ,它们是切线形式和放射形式两种不同方向的迁移路祖细胞的共同源地。 相似文献
27.
天然角蛋白自身反应性B细胞亚群及功能的分析 总被引:2,自引:0,他引:2
目的:明确天然角蛋白反应性B细胞的亚群及解剖定位,初步分析其分泌天然抗角蛋白自身抗体(anti-keratinautoantibody,AKautoAb)的能力。方法:取SPF级C57BL/6小鼠的脾细胞和腹腔细胞,荧光抗体染色后用流式细胞仪分析角蛋白反应性B细胞亚群。将脾脏和腹腔淋巴细胞体外培养后,用ELISA分析AKautoAb的滴度,用ELISPOT法分析分泌AKautoAb的B细胞数。结果:腹腔中几乎所有结合角蛋白的B细胞均为B-1a细胞,脾脏中结合角蛋白的B细胞以边缘带B细胞为主。腹腔细胞中分泌AKautoAb的细胞数显著多于脾细胞,其培养上清中AKautoAb的滴度显著高于脾细胞。结论:角蛋白反应性B细胞存在于3个成熟B细胞亚群:B-1细胞、滤泡B细胞和边缘带B细胞,其中CD5 的B-1a细胞具有活跃的分泌AKautoAb的能力。 相似文献
28.
N. V. Samosudova V. P. Reutov N. P. Larionova 《Bulletin of experimental biology and medicine》2008,146(1):9-13
Ultrastructure of synaptic vesicles in axon terminals of granule cells from isolated cerebellum of Rana temporaria frogs under the influence of NO-generating compound NaNO2 in various concentrations and electrical stimulation was evaluated by the method of electron microscopy. NO-generating compound
in low concentration induced translocation of synaptic vesicles and formation of small clusters. The size and structure of
synaptic vesicles remained unchanged under these conditions. Increasing the concentration of NaNO2 led to swelling of synaptic vesicles, formation of arranged heaps from individual vesicles or fusion of their content. Electrical
stimulation of the cerebellum in the presence of NaNO2 increased damage to synaptic vesicles. These experimental data model some stages observed in stroke. The formation of clusters
from synaptic vesicles is a compensatory and adaptive response maintaining the structure of synaptic vesicles and protecting
neurons from high concentrations of glutamate. Glutamate produces a toxic effect on nerve cells and glial cells of the cerebellum
under pathological conditions, which is accompanied by impairment of signal transduction from presynaptic to postsynaptic
neurons.
__________
Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 7, pp. 13–17, July, 2008 相似文献
29.
J. HAU P. SVENDSEN J. CHEMNITZ B. TEISNER J.G. WESTERGAARD 《American journal of reproductive immunology (New York, N.Y. : 1989)》1983,3(3):124-126
ABSTRACT: Two pregnancy-associated murine proteins, PAMP-1 and PAMP-2, have been found to be immunologically cross-reacting analogues to the human proteins pregnancy zone protein (PZP) and pregnancy-specific beta1-glycoprotien (SP-1), respectively. In this study, the physiochemical and biological properties of the proteins are compared and the effect on pregnancy of administration of monospecific antibodies against the proteins is reported. 相似文献
30.
A "floral" variant of nodal marginal zone lymphoma 总被引:1,自引:0,他引:1
Karube K Ohshima K Tsuchiya T Yamaguchi T Kawano R Suzumiya J Harada M Kikuchi M 《Human pathology》2005,36(2):202-206
We describe 6 cases of a specific variant of nodal marginal zone lymphoma with "floral" lymph follicles in patients ranging in age from 18 to 66 years. All 6 patients had lymphadenopathy, either local (n = 5) or systemic (n = 1), and good performance status (0), and none had fever, weight loss, or night sweating. They all underwent excisional biopsy. Histologically, all lesions had a distinctive morphology, with proliferation of medium-sized atypical lymphoid cells in the marginal zone, hyperplastic lymph follicles with enlarged germinal centers, and a thickened mantle zone. In places, folliculolysis was observed. On immunohistochemical staining, the atypical lymphoid cells showed a B-cell phenotype (CD20 +), IgM positivity in 2 of 5 cases, and negativity for CD5, CD10, CD23, CD43, bcl-6, and IgD. Polymerase chain reaction examination for immunoglobulin heavy chain in 5 cases showed monoclonality in all. Five patients did not receive adjuvant chemotherapy and had no recurrences. The patient with systemic lymphadenopathy received chemotherapy and had a complete response without relapse. This variant should be differentiated from the usual nodal marginal zone lymphoma because of its specific clinical and pathological features. 相似文献