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61.
Summary The appearance of perinucleolar electron-dense spots in the nuclei of macroconidia ofNeurospora crassa incubated at 46C and their disaggregation after shift-down to 25 C have been investigated by high-resolution autoradiography after (5-3H) uridine pulses with or without chase periods. The RNA of these ribonucleoprotein-rich dense spots has been found to originate mainly from the heatsensitive nucleolus; after return to 25 C, the nucleolar activity was recovered and the RNA material stored either in an unprocessed or a mature rRNA form in the dense spots was found to be progressively extruded into the cytoplasm.  相似文献   
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Summary The possibility of giving C. parvum intrapleurally (i.p.) was investigated. C. parvum was given post-operatively either i.p. only or i.p. and intravenously (i.v.) simultaneously. The dose varied from 0.1–10 mg i.p. All patients had been operated for a bronchial carcinoma. Results: (1) Subjective complaints of either dyspnoea, thoracic pain, chills or nausea occured in 31 of 63 patients. No clear dose relation was found. A feeling of discomfort and fever could occur for another 3–4 days after the above more acute symptoms had disappeared. (2) Increased fever (0.5° C) occurred in 71% of the patients injected i.p. only. (3) No anaphylactic reaction was observed. (4) Increased total white blood cell counts (<20%) occurred in 38 patients. The WBC increase was mainly due to higher number of neutrocytes and granulocytes. Total lymphocyte, monocyte, eosinophilic, and basophilic granulocytes values per mm3 circulating blood remained unchanged, except at the dose of 7 mg C. parvum i.p. when monocyte values were increased significantly from 576±247 to 1100±578/mm3. (5) Moderate to severe effusions were observed radiologically in three patients after C. parvum intrapleurally.The study group is: M. Kaufmann, J. Stjernswärd (Ludwig Institut for Cancer Research, Lausanne Branch, Switzerland), M. Zelen, K. Stanley (Frontier Science and Technology Research Foundation, Inc. Amherst, New York, USA), D. S. Freestone, R. Bomford, M. T. Scott, T. Priestman (The Wellcome Research Laboratory, Beckenham, England), C. Mouritzen, G. Ahlbom (Dept. of Thoracic and Cardiovascular Surgery, Aarhus Kommunehospital, Aarhus, Denmark), N. Konietzko, D. Greschuchna (Ruhrland Klinic, Essen-Haidhausen, Germany), P. Hilgard (Innere Klinik und Poliklinik [Tumorforschung] Essen, Germany), J. Vogt-Moykopf, D. Zeidler, H. Toomes (Thoraxchirurgische Spezial-Klinik, Heidelberg-Rohrbach, Germany), F. Krause, R. Rios (Thoraxchirurgische Abt., Fachkrankenhaus für Lungen- und Bronchialerkrankungen, Löwenstein, Germany), J. Orel, M. Benedik, B. Hrabar (Clinical Center, Dept. of Thoracic Surgery, Ljubljana, Yugoslavia), S. Plesnicar (The Institute of Oncology, Ljubljana, Yugoslavia), H. A. Rostad, J. R. Vale (Rikshospital, Oslo, Norway), S. Hagen, S. Birkeland, (Ulleval Hospital, Oslo, Norway), T. Harbitz, R. Nissen-Meyer (Aker Hospital, Oslo, Norway), L. Rodriguez, V. O. Björk, K. Böök (Karolinska Sjukhuset, Thoracic Clinic, Stockholm, Sweden), E. Gradel, J. Hasse, P. Holbro (Kantonsspital, Thoraxchirurgische Klinik, Basel, Switzerland), L. Eckmann (Tiefenauspital, Chir. Univ.-Klinik, Bern, Switzerland), B. Nachbur, T. Liechti (Inselspital, Dept. of Thoracic and Cardiovascular Surgery, Bern, Switzerland), H. Cottier (Inst. of Pathology, Inselspital, Bern, Switzerland), W. Maurer, M. Kaufmann, P. Froelicher (Bürgerspital, Surgical Dept., Solothurn, Switzerland), H. Denck, N. Pridun (Krankenhaus der Stadt Wien-Lainz, Chir. Abt., Vienna, Austria), K. Karrer (Institute for Cancer Research, University of Vienna, Austria) Reprint requests should be addressed to any of the members listed above, or to the Ludwig Lung Cancer Trial, Operation Office, LICR, CH-1066 Epalinges, Switzerland. (For Current Contents, etc., please use above address)  相似文献   
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1. The effect of dimethyl sulfoxide (Me2SO) and ethylene glycol on two different preparations of the sarcoplasmic reticulum, i.e. native membranes and membranes whose phospholipids were hydrolyzed by phospholipase A, were investigated using ATP and p-nitrophenylphosphate as substrates. 2. Me2SO and ethylene glycol inhibit both calcium-dependent ATP hydrolysis and ATP-supported calcium transport by native vesicles. 3. In contrast, calcium-dependent p-nitrophenylphosphatase activity as well as p-nitrophenyl-phosphate-supported calcium transport are activated by both agents at concentrations lower than 30% (v/v). 4. Me2SO strongly stimulates p-nitrophenylphosphate activity of vesicles treated with phospholipase A, but has relatively little effect on p-nitrophenylphosphatase activity of native vesicles. 5. Up to a concentration of approximately 40% Me2SO (v/v) the inhibiting effect on the calcium-dependent ATPase is fully reversible, but only partially reversible on calcium transport. 6. In the concentration range where Me2SO inhibits ATP hydrolysis and calcium transport, it does not affect ATP binding to the membranes nor calcium-dependent formation of phospho-protein. 7. The rate of dephosphorylation as well as the rate of Pi exchange between ATP and ADP are markedly reduced by the presence of 30% Me2SO (v/v). 8. While Me2SO inhibits passive calcium efflux, ethylene glycol produces a considerable activation. 9. ADP-dependent calcium efflux and ATP synthesis are activated by 15% Me2SO (v/v). Ethylene glycol reduces both activities. 10. The results suggest that the respective substrate-enzyme complexes are differently affected by the agents, resulting either in inhibition or stimulation  相似文献   
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寻螨属Zetzellia在中国曾报道了两种:苹果寻螨Z.mail(Ewing)和北京寻螨Z.beijing Wang and Xu1987.本文描述了寻螨属一新种,庐山寻螨Z.lushanensis sp.nov.模式标本保存于江西大学生物系.文内测量单位为μm。  相似文献   
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李贵山  梁妮 《蛇志》1991,3(4):4-5
本文选用金黄地鼠的微血管,利用显微高速摄影技术,放大微观流场和血细胞,连续地“冻结”短瞬间的变化状态,把物理图象呈现在胶片上,经图像分析和数据处理,从定性及定量方面研究血液微流变学,为生命科学和医学研究提供了又一种新的方法。  相似文献   
66.
BackgroundIn Phase II/III randomized controlled clinical trials for the treatment of acute uncomplicated malaria, pyronaridine–artesunate demonstrated high efficacy and a safety profile consistent with that of comparators, except that asymptomatic, mainly mild-to-moderate transient increases in liver aminotransferases were reported for some patients. Hepatic safety, tolerability, and effectiveness have not been previously assessed under real-world conditions in Africa.Methods and findingsThis single-arm, open-label, cohort event monitoring study was conducted at 6 health centers in Cameroon, Democratic Republic of Congo, Gabon, Ivory Coast, and Republic of Congo between June 2017 and April 2019. The trial protocol as closely as possible resembled real-world clinical practice for the treatment of malaria at the centers. Eligible patients were adults or children of either sex, weighing at least 5 kg, with acute uncomplicated malaria who did not have contraindications for pyronaridine–artesunate treatment as per the summary of product characteristics. Patients received fixed-dose pyronaridine–artesunate once daily for 3 days, dosed by body weight, without regard to food intake. A tablet formulation was used in adults and adolescents and a pediatric granule formulation in children and infants under 20 kg body weight. The primary outcome was the hepatic event incidence, defined as the appearance of the clinical signs and symptoms of hepatotoxicity confirmed by a >2× rise in alanine aminotransferase/aspartate aminotransferase (ALT/AST) versus baseline in patients with baseline ALT/AST >2× the upper limit of normal (ULN). As a secondary outcome, this was assessed in patients with ALT/AST >2× ULN prior to treatment versus a matched cohort of patients with normal baseline ALT/AST. The safety population comprised 7,154 patients, of mean age 13.9 years (standard deviation (SD) 14.6), around half of whom were male (3,569 [49.9%]). Patients experienced 8,560 malaria episodes; 158 occurred in patients with baseline ALT/AST elevations >2×ULN. No protocol-defined hepatic events occurred following pyronaridine–artesunate treatment of malaria patients with or without baseline hepatic dysfunction. Thus, no cohort comparison could be undertaken. Also, as postbaseline clinical chemistry was only performed where clinically indicated, postbaseline ALT/AST levels were not systematically assessed for all patients. Adverse events of any cause occurred in 20.8% (1,490/7,154) of patients, most frequently pyrexia (5.1% [366/7,154]) and vomiting (4.2% [303/7,154]). Adjusting for Plasmodium falciparum reinfection, clinical effectiveness at day 28 was 98.6% ([7,369/7,746] 95% confidence interval (CI) 98.3 to 98.9) in the per-protocol population. There was no indication that comorbidities or malnutrition adversely affected outcomes. The key study limitation was that postbaseline clinical biochemistry was only evaluated when clinically indicated.ConclusionsPyronaridine–artesunate had good tolerability and effectiveness in a representative African population under conditions similar to everyday clinical practice. These findings support pyronaridine–artesunate as an operationally useful addition to the management of acute uncomplicated malaria.Trial registrationClinicalTrials.gov NCT03201770.

Gaston Tona Lutete and co-workers report on safety and effectiveness of the antimalarial drug pyronaridine-artesunate in African countries.  相似文献   
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