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91.
A series of substituted 2,2′-bipyridine derivatives was prepared using the Kröhnke reaction and alkylation of 4,4′-dimethyl-2,2′-bipyridine. These compounds were screened for fungicidal activity against 9 plant diseases. 5-Phenyl-2,2′-bipyridine exhibited strong preventative and curative fungicidal activity against wheat powdery mildew (Erisyphe graminis) and wheat leaf rust (Puccinia recondita).  相似文献   
92.
Summary X-inactivation patterns were studied by replication analyses both in lymphocytes and skin fibroblasts of two patients carrying balanced X-autosome translocations, t(X;10)-(pter;q11) and t(X;17)(q11;q11), and one patient with an unbalanced translocation t(X;22)(p21;q11). Preferential late replication of the normal X chromosome was found in lymphocytes of both patients carrying balanced translocations and in skin fibroblasts of the patient carrying the translocation t(X;17). However, skin fibroblasts of the patient with a translocation t(X;10) showed preferential late replication of the abnormal der(X) chromosome with no spreading of late replication to the autosomal segment. In the case of unbalanced translocation t(X;22) there was preferential late replication of the der(X) chromosome both in lymphocytes and skin fibroblasts. The abnormal phenotype of the patients is discussed in relation to the observed X-inactivation patterns and the variability of the patterns in different tissues.  相似文献   
93.
Résumé Un extrait de S. schenckii a été préparé à partir de levures vivantes provenant d'une culture agitée pendant 3 jours à 35° C et à l'obscurité dans du milieu BHI (brain heart infusion). Il a été obtenu par broyage au broyeur cellulaire MSK et amélioré par une congélation-décongélation. Ses constituants, séparés par électrophorèse, ont été révélés par leur activité enzymatique; 30 bandes ont ainsi pu être caractérisées. Ces activités enzymatiques ont été recherchées au niveau des fractions de l'extrait révélées par un hyperimmunsérum de lapin: 16 sur les 22 précipités sont identifiés par leur pouvoir catalytique. L'ordre d'apparition des premiers anticorps chez le lapin immunisé et leur identification complètent cette étude. Les conditions de culture et de préparation permettant d'améliorer la qualité de l'extrait sont également précisées.
An extract from living yeast forms of S. schenckii was prepared. The yeasts originated from a shake culture in B.H.I. broth (Difco) incubated for 3 days at 35°C in darkness; they were harvested, washed and disrupted with glass beads in a model MSK Braun mechanical cell homogenizer; a freezing-thawing was added to improve the extract.After electrophoretic separation in agarose gel, the extract's components were characterized by their enzymic activity; with this technique, 30 bands were revealed. These enzymic activities were also investigated on the antigenic fractions of the extract revealed by a rabbit hyperimmunserum: 16 among 22 immunoprecipitates are identified by their catalytic properties. Study of the earliest precipitating antibodies (appearing-order and enzymic caracterization) in rabbits just immunized completes this work. How to ameliorate the quality of the extract by culture and extraction conditions is also specified.
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94.
Data on home treatment for patients with haemophilia A (factor VIII deficient haemophilia) were compiled for 1975 and 1976 from questionnaires answered by directors of haemophilia centres throughout the United Kingdom. There were 48 haemophilia centres in 1975 and 71 in 1976. The number of patients on or in training for home treatment increased from 267 to 488 in the two years, and a further 241 haemophiliacs were considered suitable for home therapy by the end of 1976. Apart from a small (but increasing) number of haemophiliacs on prophylactic treatment, most patients were on low-dose (250-500 units) on-demand regimens, using a mean of 20 000 factor VIII units per patient per year in 1976. An estimated 55% of the blood product used for home therapy in the UK in 1976 was imported from commercial sources. Despite the fact that the numbers of patients on home treatment have increased, so that about 60% of the potential population were receiving or being considered for home treatment in 1976, inadequacies in the service still remain. In some centres follow-up is clearly inadequate; about 15% of patients still rely on cryoprecipitate; and too little money has been invested in making the NHS self-sufficient in factor VIII production.  相似文献   
95.
96.
Within ventricular myocardial cells of the mouse, the myoplasmic regions located immediately adjacent to the Z lines of the sarcomeres contain a variety of structures. These include: (1) transversely oriented 10 nm (‘intermediate’) filaments that apparently contribute to the cytoskeleton of the myocardial cell; (2) the majority of the transverse elements of the T-axial tubular system; (3) specialized segments of the sarcoplasmic reticulum (SR) that are closely apposed to the sarcolemma or T-axial tubules (junctional SR); (4) ‘extended junctional SR’ (‘corbular SR’) that exists free of association with the cell membrane; (5) ‘Z tubules’ of SR that are intimately apposed to the Z line substance; and (6) leptofibrils. In addition, fasciae adherentes supplant Z lines where myofibrils insert into the transverse borders (intercalated discs) of the cells. The concentration of these myocardial components at the level of the Z lines suggests that a particular specialization of structural and physiological activities exists in the Z-level regions of the myoplasm. In particular, it appears that the combination of intermediate filaments, T tubules, and Z-level SR elements forms a series of parallel planar bodies that extend across each myocardial cell to impart transverse rigidity. The movement and compartmentation of calcium ion (Ca2+) would seem especially active near the Z lines of the myofibrils, in view of the preferential location there of Ca2+-sequestering myocardial structures such as T tubules, junctional SR, extended junctional SR and Z tubules.  相似文献   
97.
Under precise conditions, SDS PAGE allows purification of a photoactive P700-chla-protein complex from eucaryotic cells. The yield of P700 recovery is close to 100%. A total protein content equivalent to about 140 kD for one mole of P700 has been estimated by chemical analysis, and electrophoresis revealed the presence of two peptidic chains with MWs close to 65 kD. Photochemical and structural properties of this complex are given and compared with those of other complexes previously isolated.  相似文献   
98.
Summary The contribution of natural cell-mediated cytotoxicity (NCMC) to tumor-directed cytotoxicity is unknown. This study was undertaken to correlate changes in NCMC to a single target cell (K-562) with responses to therapy in patients with small cell carcinoma of the lung, resectable stage I non-small cell carcinoma of the lung, and stage I and II melanomas. Data from these studies suggested that these patients have depressed levels of NCMC to K-562 compared with a normal age-matched control population. However, NCMC levels appear to fluctuate with tumor burden, being highest in patients with large tumor masses and lowest in patients with no clinical evidence of tumor following a successful response to therapy.  相似文献   
99.
The effects of 19-hydroxyprostaglandins (19-OH-PGs) were tested in vivo on the rabbit oviduct and uterus and on the rhesus monkey (Macaca mulatta) uterus. The 19-OH-PGEs suppressed spontaneous oviductal and uterine activity in the rabbit. The qualitative effect on the rabbit oviduct of 19-OH-PGEs was similar to that of PGE2. However, the typical response of the rabbit uterus to PGE2 was an increase in muscle activity. With regard to the rabbit oviduct, 19(R)-OH-PGE2 was as potent as PGE2, but 19(S)-OH-PGE2 was approximately 1/2 as potent as PGE2. Based on the dose of 19-OH-PGEs usually required to cause a minimal suppression and the dose of PGE2 required to cause a minimal stimulation of rabbit uterine activity, 19(R)-OH-PGE2 was twice as potent as PGE2 while 19(S)-OH-PGE2 was 1/2 as potent as PGE2. Stimulatory effects on the rabbit oviduct and uterus were observed following administration of 19-OH-PGFs and PGF2alpha. The potency on the rabbit oviduct of 19(S)-OH-PGF2alpha was about 1/5 to 1/10 that of PGF2alpha; the potency of 19(R)-OH-PGF2alpha was about 1/10 to 1/20 that of PGF2alpha. Both 19-OH-PGFs were approximately 1/5 to 1/10 as potent as PGF2alpha on the rabbit uterus. At the doses tested 19-OH-PGFs were inactive on the monkey uterus. Thus, these compounds are at least 1/5 as active as PGF2alpha. In contrast, 19(R)-OH-PGE2 had approximately the same potency as PGE2 in stimulating monkey uterine activity; but 19(S)-OH-PGE2 was approximately 1/3 as potent as PGE2.  相似文献   
100.
The effects of prostaglandin (PG)F2alpha and PGF2alpha, 1-15 lactone were compared in luteal phase, non-pregnant and in early pregnant rhesus monkeys. Animals treated with either PG after pretreatment with human chorionic gonadotropin (hCG) had peripheral plasma progesterone concentrations that were not statistically different from those in animals treated with hCG and vehicle. However, menstrual cycle lengths in monkeys treated with PGF2alpha, 1-15 lactone were significantly (P less than 0.02) shorter than those in vehicle treated animals. In the absence of hCG pretreatment, plasma progesterone concentrations were significantly (P less than 0.008) lower by the second day after the initial treatment with either PGF2alpha or PGF2alpha, 1-15 lactone than in vehicle treated monkeys. Menstrual cycle lengths in monkeys treated with either PG were significantly (P less than 0.04) shorter than those in animals treated with vehicle. There were no changes in plasma progesterone concentrations in early pregnant monkeys treated with PGF2alpha, and pregnancy was not interrupted. In contrast, plasma progesterone declined and pregnancy was terminated in 5 of 6 early pregnant monkeys treated with PGF2alpha, 1-15 lactone. These data indicate that PGF2alpha, 1-15 lactone decreases menstrual cycle lengths in non-pregnant rhesus monkeys. More importantly, PGF2alpha, 1-15 lactone terminates early pregnancy in the monkey at a dose which is less than an ineffective dose of PGF2alpha.  相似文献   
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