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81.
In order to evaluate the efficacy of albendazole for the treatment of taeniasis, regimens of 400 mg x 1 day, 800 mg x 2 days, 800 mg x 3 days, 1200 mg x 2 days, and 1200 mg x 3 days were compared. Of 66 cases treated and investigated 7-14 days after treatment, 52 were still expelling proglottids. Three months posttreatment, these cases were re-treated with atabrine at 1.2 g per case for males and 1.0 g per case for females. Fifty-seven patients expelled worms or parts of tapeworms. The nine negatives may represent the number cured by the treatment with albendazole. The cure rates with albendazole for various regimens were up to 50% for 800 mg x 3 days, 1200 mg x 2 days or 1200 mg x 3 days, 14.3% for 800 mg x 2 days, and 0% for 400 mg x 1 day or 800 mg x 1 day. This study shows that albendazole is not very effective in the treatment for taeniasis. 相似文献
82.
83.
日本落叶松人工林针叶中矿质营养元素的季节吸收特点及其相互关系 总被引:3,自引:1,他引:2
本文测定了日本落叶松人工林针叶中N、P、K、Ca、Mg、Cu、Zn、Fe、Mn9种矿质营养元素含量并研究了生长期内元素含量的变化规律。结果表明,在生长期内各元素含量随季节变化可用修正指数曲钱描述;探讨了落叶松针叶中常量元素与某些土壤化学因子之间的关系。土壤有机质仅与土壤全量氮、水解氮表现了显著的线性相关,与落叶松针叶中的氮没有直接的线性相关。土壤中钙镁的含量则表现出明显的对针叶中磷、钾的含量的制约关系。在日本落叶松针叶中的氮、磷、钾3个元素之间,氮、磷的比值与钾的含量有显著的线性负相关,而磷与钾之间则表现为显著的线性正相关关系。 相似文献
84.
The sporulation gene spoVK of Bacillus subtilis was cloned by use of the insertional mutation spoVK::Tn917 omega HU8. The spoVK gene was shown to be the site of an incorrectly mapped mutation called spoVJ517. Thus, a separate spoVJ gene as defined by the 517 mutation does not exist and is instead identical with spoVK. 相似文献
85.
K Fan Q Ruan L Sensenbrenner B D Chen 《Journal of immunology (Baltimore, Md. : 1950)》1992,149(1):96-102
Murine peritoneal exudate macrophages (PEM) display multiple CSF receptors. In this study, the expression of granulocyte-macrophage (GM)-CSF receptors in PEM was studied. PEM displayed over 5000 single type, high affinity GM-CSF receptors/cell with a Kd = 38 to 42 pM and an apparent molecular mass of 86,000 Da. Treatment of PEM with low, but not high, concentrations of recombinant murine (rMu) GM-CSF continuously for 24 h resulted in a marked up-regulation of GM-CSF receptors in PEM. A similar up-regulation of GM-CSF receptors also was detected in PEM cultures treated with rMuIL-3 (1-100 ng/ml) for 24 h or longer, regardless the doses of rMuIL-3 added in this case. Scatchard analysis of equilibrium binding showed that the enhanced binding activities in both cases were due to an increase in total number of GM-CSF receptors rather than changes in receptor affinity. Contrariwise, treatment with recombinant human macrophage-CSF (greater than 100-1000 ng/ml) partially inhibited the expression of GM-CSF receptors in PEM. Removal of rMuGM-CSF from culture medium 24 h after treatment led to a further up-regulation of GM-CSF receptors over a 4 to 24-h period, depending on the doses of initial treatment. On the other hand, removal of rMuIL-3 from culture medium after prolonged treatment did not result in further increase in GM-CSF receptors. The protein synthesis inhibitor cycloheximide abrogated GM-CSF receptor up-regulation induced by both rMuIL-3 and rMuGM-CSF, whereas actinomycin D inhibited only the second (8-24 h) phase of GM-CSF receptor up-regulation induced by exposure to high concentrations rMuGM-CSF (10 ng/ml). These findings suggest that rMuGM-CSF and rMuIL-3 up-regulate GM-CSF receptors in PEM in part through similar or identical metabolic pathways and provide further evidence of a close linkage between IL-3 and GM-CSF receptors. 相似文献
86.
Shih-fang Fan M. M. Dewey B. Gaylinn B. Chu 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1992,162(6):508-512
Summary In dynamic light scattering, measurements of the intensity-intensity time correlation function from a suspension of rod-like particles of length L could reveal dynamical information related to translational and internal motions of those particles. For a suspension of thick filaments isolated from the myosin-regulated, striated muscles of Limulus at KL>1 (where K is the scattering vector), the average characteristic linewidth (
) increased with the addition of Ca2+ or with the depletion of ATP. The increase in the
with the addition of Ca2+ could be due to the presence of energy-requiring, high-frequency motions of the crossbridges activated by Ca2+. The increase in
which occurred with the depletion of ATP was assumed to be mainly due to the thermal motions of the crossbridges after they had moved radially away from the filament backbone. The percentage increase in
following the addition of Ca2+ was found to be seasonal, i.e., values of
obtained from thick filaments isolated between the middle of June and the middle of September were smaller than those obtained during the rest of the year. The effect of temperature on the percentage increase in
was also different. The increase showed a maximum at about 35°C during the summer and at about 25°C at other times. However, the percentage increase in
developed under ATP-depleted conditions showed no temperature-related maximum. The number of bound Ca2+ per myosin molecule was 1 during the summer and 2 at other times.Abbreviations DLS
dynamic light scattering
- L
length
- K
scattering vector
- SDS-PAGE
sodium dodecyl sulfate polyacrylamide gel electrophoresis
-
average characteristic line width
Deceased 相似文献
87.
Eosin Y staining of proteins in polyacrylamide gels. 总被引:1,自引:0,他引:1
A staining method is described in which various proteins in polyacrylamide gels can be stained by using eosin Y. After a brief incubation of a polyacrylamide gel in an acidic solution of 1% eosin Y, various proteins, including human erythrocyte membrane sialoglycoproteins which are not detectable by Coomassie blue R-250 (CB), can be detected with a sensitivity of 10 ng protein. This is far more sensitive than CB staining and is comparable to the sensitivity of silver staining. In a Western blot, the antigenicity of an eosin Y stained protein is retained. In addition, proteins on an immunoblot sheet can be detected by eosin Y staining. The method described is rapid, sensitive, and reproducible with various proteins in polyacrylamide gels and has the added advantage of also staining sialoglycoproteins. 相似文献
88.
Q-Band ENDOR studies on carbon monoxide dehydrogenase (CODH) from the acetogenic bacterium Clostridium thermoaceticum provided unambiguous evidence that the reaction of CO with CODH produces a novel metal center that includes at least one nickel, at least three iron sites, and the carbon of one CO. The 57Fe hyperfine couplings determined by ENDOR are similar to the values used in simulation of the M?ssbauer spectra [Lindahl et al. (1989) J. Biol. Chem. 265, 3880-3888]. EPR simulation using these AFe values is equally good for a 4Fe or a 3Fe center. The 13C ENDOR data are consistent with the binding of a carbon atom to either the Ni or the Fe component of the spin-coupled cluster. The 13C hyperfine couplings are similar to those determined earlier for the C0-bound form of the H cluster of the Clostridium pasteurianum hydrogenase, proposed to be the active site of hydrogen activation [Telser et al. (1987) J. Biol. Chem. 262, 6589-5694]. The 61 Ni ENDOR data are the first nickel ENDOR recorded for an enzyme. The EPR simulation using the ENDOR-derived hyperfine values for 61Ni is consistent with a single nickel site in the Ni-Fe-C complex. On the basis of our results and the M?ssbauer data [Lindahl et al. (1989) J. Biol. Chem. 265, 3880-3888], we propose the stoichiometry of the components of the Ni-Fe-C complex to be Ni1Fe3-4S greater than or equal to 4C1, with four acid-labile sulfides. 相似文献
89.
从培养在液体培养基中的香菇、美味侧耳和平菇的单核菌丝用酶法分离了原生质体。施加0.5MHz、500PV/cm的正弦波和μs、6000PV/cm方形脉冲的电场诱导下使其电融合。电融合后的融合子和原生质体在固体培养基上植板培养成菌落。在显微镜下检查融合子菌株菌丝的锁状联合选出从融合子长成的菌株。香菇和美味侧耳的融合菌株产生频率为61.53%,香菇和平菇的融合菌株产生频率为32.58%。根据融合菌株与亲本的拮抗作用和他们的过氧化物同工酶和酯酶同工酶的电泳酶谱与其亲本酶谱的不同,证实这些融合菌株是从融合的异核体生长成的。同时讨论了电融合方法和结果。 相似文献
90.
John A. Demoss T.Y. Fan Randolph H. Scott 《Archives of biochemistry and biophysics》1981,206(1):54-64
Nitrate reductase from Escherichia coli, purified to homogeneity after release from membranes by deoxycholate treatment, was composed of two subunits of 155,000 (α) and 58,000 (β) daltons and contained no cytochrome b1. Analysis of fractions at different stages of purification by gel electrophoresis and immunoprecipitation revealed that during the early steps of the purification cytochrome b1 dissociated from the enzyme and the β subunit was altered in size as determined by sodium dodecyl sulfate-gel electrophoresis. Analysis of the peptide patterns obtained by partial proteolysis of isolated α and β subunits established that these subunits are composed of distinct sequences and ruled out a precursor-product relationship between the two subunits. The β subunit was altered during the purification by loss of a 2000-dalton fragment, apparently from its carboxyl terminus. The protease inhibitor tosyllysine chloromethylketone protected nitrate reductase from more extensive degradation by endogenous proteases during the purification but did not prevent the removal of the 2000-dalton fragment. This carboxyl terminal fragment was part of a 15,000-dalton sequence which was removed by trypsin and which was required for the self-associating character of the unmodified enzyme monomers. From the structural changes which occurred during the purification procedure, it is proposed that the carboxyl terminal segment of the β subunit is involved in the binding of nitrate reductase to cytochrome b1 and its association with the membrane. 相似文献