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81.
Ultracryotomy: development and application (with examples from the yeast cytology) (author's transl)
Konrad Joachim Böhm 《Acta histochemica》1980,66(1):59-84
The preparation steps usually necessary for obtaining ultrathin frozen sections of biological material (chemical prefixation, enclosing, cryoprotective treatment, freezing, sectioning, and post-staining the sections for transmission electron microscopy) are submitted to a critical analysis. The application of cryo-ultramicrotomy, in particularly for cytochemical purposes, is reviewed. Fundamental considerations of chemical prefixation and poststaining are supported by examples from yeast cytology. Furthermore, the efficiency of the cryo-ultramicrotomy (electron optical resolution of ultrastructural details) is demonstrated on yeast cells and protoplasts. 相似文献
82.
Two mediated smoking cessation programs were subjected to a field evaluation. The Quit Kit is a printed self-help package, and "Calling It Quits" consists of five segments which were aired on the local television news. A sample of 239 persons requested the Quit Kit and were followed. At the 2-month and 12-month follow-ups, respectively, 13.6% and 17.9% of those surveyed reported abstinence. Results indicate the potential of mediated interventions. 相似文献
83.
F M Baker 《General hospital psychiatry》1985,7(2):138-143
In response to the spiraling anger and frustration voiced by the emergency room (ER) medical staff and the observed negative interactions between the alcohol-dependent patient and the ER staff, the author completed a 6-month retrospective review of all patients evaluated by the ER service with a complaint of alcohol abuse, chronic alcoholism, or requesting detoxification. As a result of that study, an ER-based comprehensive approach to the management of this population was proposed. Utilizing an existing Connecticut state statute, a specific approach to manage the skid-row alcoholic arriving repeatedly in the ER was developed. I report on this ER-based model and an approach to "capturing" the skid-row alcoholic. 相似文献
84.
M. C. Malet-Martino P. Servin J. Bernadou J. P. Armand R. Martino 《Investigational new drugs》1987,5(3):273-279
The urinary excretion of doxifluridine (5 dFUrd) and its metabolites was determined during five days of chemotherapy using fluorine-19 nuclear magnetic resonance spectrometry. The daily urinary excretion of 5 dFUrd and its metabolites was high (-100% of the 5 dFUrd administered) and nearly constant through out the treatment. By far the major excreted compounds were unchanged 5 dFUrd and -fluoro--alanine which made up respectively -40% and -50% of the total. Neither accumulation of 5 dFUrd nor significant modifications in its metabolism were observed during the treatment. 相似文献
85.
Lineage relationship of chronic lymphocytic leukemia and hairy cell leukemia: studies with TPA 总被引:2,自引:0,他引:2
F Caligaris-Cappio G Janossy D Campana M Chilosi L Bergui R Foà D Delia M C Giubellino P Preda M Gobbi 《Leukemia research》1984,8(4):567-578
The tumor promoting agent TPA (phorbol ester; 1.6 X 10(-8)M) was used to induce the differentiation in vitro of B-chronic lymphocytic leukemia (B-CLL) cells from 14 untreated patients. The uninduced phenotype was SIg+, Mrbc+, RFT-1+, RFA-4-, FMC7-. After 72 h incubation with TPA, B-CLL cells became RFA-4+, FMC7+ and lost the capability of Mrbc rosetting. Large proportions of the "induced" cells also showed morphological and ultrastructural changes, such as undulating membranes and bleblike protusions and became strongly positive for tartrate resistant acid phosphatase (TRAP+) and also contained cytoplasmic immunoglobulins. These features are very similar to the features of hairy cell leukemia (HCL). These observations confirm previous clinical findings that B-CLL and HCL are related disorders of the B lineage. The development of "hairy" features in induced B-CLL and in HCL seems to be a malignancy-associated feature because the Mrbc+ normal B cells (B-CLL-equivalent cells) isolated from tonsil also develop TRAP positivity but no membrane aberrations. 相似文献
86.
Yoonyoung Jang Yoon-Jung Choi Youn-Hee Lim Kyung-Shin Lee Bung-Nyun Kim Choong Ho Shin Young Ah Lee Johanna Inhyang Kim Yun-Chul Hong 《Yebang Ŭihakhoe chi》2021,54(1):37
ObjectivesBisphenol A (BPA) is used in the electrical, mechanical, medical, and food industries. Previous studies have suggested that BPA is an endocrine disruptor. Regulation of BPA has led to increased use of bisphenol F (BPF) and bisphenol S (BPS). However, few studies have investigated the associations of BPF and BPS with thyroid dysfunction in children. Our study investigated the associations of prenatal BPA and early childhood BPA, BPF, and BPS exposure with thyroid function in 6-year-old children.MethodsPrenatal BPA concentrations were measured during the second trimester of pregnancy in an established prospective birth cohort. We measured urinary BPA, BPF, and BPS concentrations and thyroid hormone levels (thyroid-stimulating hormone, total T3, and free T4) in 6-year-old children (n=574). We examined the associations between urinary bisphenol concentrations and percentage change of thyroid hormone concentrations using multivariate linear regression. We also compared thyroid hormone levels by dividing the cohort according to BPA, BPF, and BPS concentrations.ResultsThe associations between prenatal BPA and total T3 levels were statistically significant in all models, except for girls when using a crude model. The associations between urinary BPA and BPS concentrations and levels of all thyroid hormones were not statistically significant. However, we observed that lower free T4 levels (−1.94%; 95% confidence interval, −3.82 to −0.03) were associated with higher urinary BPF concentrations in girls only.ConclusionsOur findings identified significant associations between prenatal BPA exposure and total T3 levels in all children and between BPF exposure and free T4 levels in girls only. 相似文献
87.
中华眼镜蛇毒F组分对沙鼠脑缺血再灌注损伤的保护作用 总被引:1,自引:1,他引:0
目的:研究中华眼镜它毒F组分脑缺血再灌注损伤的保护作用,方法:结扎沙鼠双侧颈总动脉1h,造成前脑缺血模型,用比色法测定脑匀浆过氧化脂质的最终产物丙二醛(MDA)的含量及超氧化物歧化酶(SOD)的活性,结果:F组分0.9,0.3,0.1mg/kg可显著抑制脑内脂质过氧化,降低MDA的含量,并提高超化物歧化酶的活,性且呈一定的量效关系,同缺血再灌组比较P<0.05,同阳性对照药尼莫通比较,P>0.05,结论:中华眼镜蛇毒F组分对脑缺血再灌注损伤有保护作用,可能与抑制自由基的生成和促进自由基的清除有关。 相似文献
88.
目的 建立准确测定姜黄属4种中药材挥发油中莪术醇含量。方法 以高效毛细管柱序升温气相色谱法测定莪术醇的含量。结果 本法能准确测定莪术醇的含量,回收率为101.4%,RSD为0.4%,还测定了4种姜黄属药物(温郁金、姜黄,桂莪术,蓬莪术)中莪术醇的含量,发现4种药材中莪中醇的含量差异显著。结论 为姜黄属药材质量的分析控制提供可行的含量测定方法。 相似文献
89.
目的 探讨切线时间常数 ( τt)在慢性阻塞性肺疾病 ( COPD,慢阻肺 )和肺心病患者 F- V曲线形状转变中的变化及临床意义。方法 测定了 90例缓解期 COPD患者 (慢支 43例 ,肺气肿 47例 )及 31例合并肺心病患者的 F- V曲线。并在 F- V曲线上测量高、中、低肺容积的切线时间常数 τt75 、τt5 0 、τt2 5 ,与正常人和吸烟者的 τt作对比分析。结果 1正常范围内 F- V曲线形状呈平台型、直线型、凸型和凹型 4种 ,| τt75 | >1s或 <1s,τt2 5 <1s,τt关系呈“青少年式”或“老年式”;2轻、中度异常的 F- V曲线呈凸型 ,| τt75 | <1s,τt2 5 ≈ 1s或 >1s,τt 关系呈“喇叭式”改变 ;3严重异常的 F- V曲线形状呈双曲线型 ,| τt75 | <1s,τt2 5 =4s~ 10 s,τt关系呈“塔式”改变。结论 双曲线型、τt2 5 极度延长和“塔式”改变是判断病情严重性的三大重要标志。该方法简便准确 ,利于在临床推广应用 相似文献
90.
目的 采用代谢组学的方法探究商陆Phytolacca acinosa醋制前后正丁醇部位肝肾毒性的差异及减毒作用机制。方法 采用UPLC-Q-TOF/MS的方法对商陆醋制前后正丁醇部位的成分变化进行研究。小鼠ig商陆生醋品正丁醇部位低、高剂量(27、54 mg/kg)28 d后,通过血清生化指标和病理切片评价商陆醋制前后的肝肾毒性差异;采用UPLC-Q-TOF/MS对血清进行数据采集;通过QI、HMDB及MetaboAnalyst 5.0寻找与商陆炮制减毒相关的差异代谢物及代谢通路。结果 商陆醋制后部分皂苷类成分含量下降显著,并能够明显降低生品导致的肝肾功能指标的异常升高。病理切片结果显示,与对照组比较,生品组的肝、肾组织病变明显;醋制后病变程度显著减轻。通路富集分析发现胆汁酸代谢可能与商陆醋制减毒密切相关;进一步对胆汁酸进行半定量分析发现,商陆醋制后能够改善生品导致的结合型胆汁酸含量的下降及次级胆汁酸含量的升高,从而改善胆汁酸代谢紊乱。结论 商陆生品具有肝肾毒性,醋制后皂苷类成分含量下降,毒性显著降低,其作用机制可能与改善胆汁酸代谢紊乱密切相关。 相似文献