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61.
Ryohei Kuwatsuru David M. Shames Andreas Mühler Jan Mintorovitch Vladimir Vexler Jeffry S. Mann Frederic Cohn David Price John Huberty Robert C. Brasch M.D. 《Magnetic resonance in medicine》1993,30(1):76-81
Magnetic resonance imaging enhanced with a macromolecular contrast medium (MMCM), albumin-Gd-DTPA, was used to estimate the plasma volume in vivo in the myocardium, lung, liver, and skeletal muscle of 10 normal rats. The plasma volumes of the same tissues in a parallel group of six rats were estimated in vitro by a conventional radioisotopic technique (111In-transferrin). Plasma volumes of myocardium, lung, liver, and skeletal muscle estimated by the MR technique (μl plas. ia cc-1 of tissue) were 101,109,163, and 11.0, respectively, while plasma volumes measured by the In-transferrin radioisotope technique (mg plasma g-1 of tissue) were 78.6, 215,143, and 11-2, respectively. Assuming a ratio of densities of aerated lung to blood of 0.45 and of other tissues to blood of 1.0, correlation between the methods was excellent (R2 = 0.99) indicating that MR imaging enhanced with MMCM permits reliable in vivo estimation of tissue plasma volume in the rat. 相似文献
62.
母血中胎儿细胞体外培养富集研究 总被引:1,自引:1,他引:0
对41名妊娠8~36周健康孕妇的外周血采用“空气培养”和“密闭培养”两种方法,通过含有胎牛血清、植物蛋白血凝素、人绒毛膜性腺激素、三磷酸腺苷酸钠、胰岛素等不同细胞培养条件的8种组合,比较分析了各种条件下对富集孕妇外周血中胎儿细胞的作用。实验表明:空气培养法及含有人绒毛膜促性腺激素和三磷酸腺苷酸钠等培养条件,有利于胎儿细胞的富集,但富集倍数相对低。并对其影响因素,假阳性和假阴性原因进行了讨论。 相似文献
63.
Michel A. Ghossain Jean-Noël Buy Alain Ruiz Denis Jacob Catherine Sciot Danile Hugol Dominique Vadrot 《Journal of magnetic resonance imaging : JMRI》1998,8(6):1203-1206
A case of hyperreactio luteinalis in an otherwise normal pregnancy is reported. Ascites was present, but no peritoneal implants or adenopathy were seen. Findings that would have suggested the correct diagnosis are the symmetrical and bilateral pattern of the mass, as well as the rather uniform size of the loculi, which were 1 to 3 cm in diameter. 相似文献
64.
目的 探讨大学生睡眠质量、负性情绪在错失恐惧与社交媒体倦怠间的中介作用。 方法 采用错失恐惧量表、社交媒体倦怠量表、匹兹堡睡眠质量指数量表、抑郁-焦虑-压力量表简体中文版对306名大学生进行调查。 结果 错失恐惧、社交媒体倦怠、睡眠质量和负性情绪之间呈两两正相关;错失恐惧能正向预测社交媒体倦怠;睡眠质量和负性情绪在错失恐惧和社交媒体倦怠之间起单独中介作用,且睡眠质量和负性情绪在错失恐惧与社交媒体倦怠之间起链式中介作用,负性情绪各维度效应皆成立。 结论 睡眠质量和负性情绪能够为错失恐惧对社交媒体倦怠的影响提供一个解释机制,大学生的错失恐惧既可以直接影响其社交媒体倦怠水平,也可以通过睡眠质量、负性情绪的独立中介效应以及睡眠质量-负性情绪的链式中介效应间接影响。 相似文献
65.
Terry L. Riss Masami Ogasawara Kenneth P. Karey David Danielpour Betty H. Stewart David A. Sirbasku 《Methods in Cell Science》1986,10(2):133-150
Summary Serum-free defined media have been developed for assay of the mitogenic effects of growth factors on human MCF-7, human T-47D, and mouse COMMA-D mammary cells as well as for identification of mitogens and inhibitors of GH4C1 rat pituitary tumor cell growth. These lines were shown to grow in vivo in response to a variety of hormones including estrogens and thyroid hormones. With mammary cells, complete hormonally and nutritionally defined media were established that supported continuous passage at 50 to 90% of the serum stimulated rate. The strategy used to measure mitogens for mammary cells was to identify nutritional conditions where the growth rate was reduced greatly without impairing the response to picomolar to nanomolar concentration of growth factors. The effects of polypeptide growth factors and tissue extracts were estimated by their addition to basal medium and measuring cell number increases or labeled thymidine incorporation into DNA. In a variation of this methodology, the MTW9/PL2 rat mammary cells were used to identify secreted autocrine growth factors; nutritionally defined conditions were sought for growth of these rat cells in the complete absence of exogenous growth factors. The factors secreted into the medium were detected by bioassays with COMMA-D or MCF-7 mammary cell lines. The effects of growth factors-inhibitors on pituitary cells were measured by a related method; the GH4C1 cells were grown at less than optimal rates in a defined medium designated TRM-1. Addition of mitogens to TRM-1 stimulated pituitary cell growth whereas addition of inhibitors caused reduced levels of growth. The methods described in this report offer new means of assaying growth factors-inhibitors for a range of mammary and pituitary tumor cells. 相似文献
66.
67.
V. Kvedariene P. Martins L. Rouanet P. Demoly 《Clinical and experimental allergy》2006,36(8):1072-1077
Background Iodinated contrast media (ICM) hypersensitivity reactions represent a serious problem. Very few clinical data concerning systematic skin testing to ICM are available. Objective To evaluate the utility of ICM skin testing in patients with ICM hypersensitivity. Material and methods All patients referred over a 6‐year period for ICM hypersensitivity past reactions were skin tested for (a) the implicated ICM, or (b) a set of ICM if they were positive for the implicated ICM or if its name was unknown. Results Forty‐four patients, with a median age of 56 years, were studied (15 males, 29 females). The ICM skin tests were positive in 10 patients (23%): one had a positive skin prick test, seven an immediate positive intradermal test (IDT) and two a delayed positive IDT. Skin tests were more often positive in patients with immediate (9/32) as compared with those with non‐immediate reactions (1/11). The time interval between the reaction and skin testing was shorter for those patients with an immediate ICM reaction and a positive skin test result (3 months [2.5–174.0]) as compared with those with an immediate ICM reaction and a negative skin test (48 months [6.8–159.0]), (P<0.05). Respiratory allergy was more frequent in the positive group (6/10 vs. 7/34, P<0.05). Conclusions Skin tests with ICM are positive in a subgroup of patients with ICM hypersensitivity and may play an important role in the diagnosis of ICM allergy. 相似文献
68.
Lymphoid and non-lymphoid cells in the adenoid of children with otitis media with effusion: a comparative study 总被引:1,自引:0,他引:1 下载免费PDF全文
E B van Nieuwkerk C J de Wolf E W Kamperdijk S van der Baan 《Clinical and experimental immunology》1990,79(2):233-239
We characterized on immuno- and enzymecytochemical level the lymphoid and non-lymphoid cells in the adenoid of children with upper respiratory tract infections (URI) and otitis media with effusion (OME) and compared these with the adenoid of children with URI without OME and with the adenoid of 'healthy' children and adults. Besides macrophages and dendritic cells we also showed the presence of MHC class II positive, ciliated, epithelial cells. These non-lymphoid cells were present in all adenoids. However, their number was less than 1% of all cells. We found no difference in lymphocyte subsets from children with URI + OME compared with those from children with URI alone. These two groups showed a significant decrease of CD8-positive (suppressor/cytotoxic) cells and a slight increase in CD22-positive B cells in comparison to 'healthy' children. No difference was found in percentages of CD4-positive (helper/inducer) cells. The localization of the lymphoid subsets in adenoids of children with URI and/or OME did not differ from those of 'healthy' children and adults. 相似文献
69.
分泌性中耳炎中耳积液和血清中sIL-2R水平的初步研究 总被引:2,自引:0,他引:2
应用酶联免疫吸附法(ELISA)对30例正常人血清(对照组)和60例分泌性中耳炎患者(SOM组)中耳积液和血清中可溶性白细胞介素2受体(sIL-2R)进行了检测。结果示SOM组血清sIL-2R水平明显高于对照组,MEF中其含量明显高于血清;鼻咽癌组血清及MEF中sIL-2R水平明显高于─般SOM组;粘液组高浆液组;慢性组高于急性组(均P<0.01)。提示:血清及MEF中sIL-2R水平的测定有助于对SOM患者免疫状态的评估;MEF中sIL-2R可能主要由局部中耳粘膜产生;MEP中高浓度的sIL-2R存在可能是SOM迁延不愈的─个原因。 相似文献
70.
目的 :探讨保留部分上鼓室外侧壁鼓室成形术的临床价值。方法 :对 4例慢性化脓性中耳炎患者行保留部分上鼓室外侧壁鼓室成形术的临床资料进行回顾性分析。结果 :经随访半年 ,听力提高 10~ 2 0dB ,鼓膜外形正常 ,全部干耳。结论 :保留部分上鼓室外侧壁鼓室成形术能有效提高听力和干耳率 ,且手术安全 相似文献