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71.
72.
V. Jiráček I. Macháčková J. Koštíř 《Cellular and molecular life sciences : CMLS》1972,28(9):1007-1009
Summary The intoxication of 15-day-old green pea seedlings with 1% gaseous SO2 causes an important concentration fall of some free ketoacids (pyruvic, oxalacetic, -ketoglutaric) and of glyceraldehyde in the roots and shoots. This fall is a consequence of the reaction of these carbonyl compounds with SO2 in the plant tissue under the formation of bisulphite adducts (-hydroxysulfonic acids), which have been chemically proved and quantitatively estimated. 相似文献
73.
74.
V. Schreiber A. Eckertová Z. Franc J. Kočí M. Rybák V. Kmentová 《Cellular and molecular life sciences : CMLS》1961,17(6):264-265
Zusammenfassung Die elektrophoretisch isolierte Franktion des hypothalamischen Extraktes erhöhtin vitro die Sekretion des thyreotropen Hormons aus der Adenohypophyse der Ratte in der Krebs-Phosphat-Ringerlösung mit 300 mg% Glukose. Die Fraktion selbst besitzt keine TSH-Wirkung. 相似文献
75.
Records of 19 species and one subspecies of water beetles of four families: Gyrinidae (two species), Dytiscidae (seven species), Hydrophilidae (10 species), and Spercheidae (one subspecies) from Pakistan are listed, based on collected material. Four genera and 10 species are recorded from Pakistan for the first time. The newly recorded genera are: Patrus, Helochares, Sternolophus and Coelostoma. The newly recorded species are: Dineutus spinosus (Fabricius, 1781), Patrus haemorrhous (Régimbart, 1891), Copelatus freudei Guignot, 1955, Copelatus sp1, Copelatus sp2, Enochrus ater (Kuwert, 1888), Helochares anchoralis Sharp, 1890, Sternolophus rufipes (Fabricius, 1792), Paracymus aeneus (Germar, 1824) and Coelostoma stultum (Walker, 1858). Zoogeographic affinities of the recorded species are discussed. According to their current distribution, the 18 species known from Pakistan can be classified into five zoogeographical categories. 相似文献
76.
AbdurRashid GhulamMustafa 《中国科学技术大学学报》2003,33(5):547-554
采用带限制算子的傅立叶拟谱方法近似求解了Burgers方程,分别证明了它的(Burgers方程)一般化的稳定性和收敛性,并获得了数值结果. 相似文献
77.
78.
Maria Luiza Beçak Sylvia M. Carneiro W. Beçak 《Cellular and molecular life sciences : CMLS》1977,33(1):25-27
Summary C banded mouse pachytene chromosomes were studied with the light and electron microscopes by the whole mount technique. The X and Y chromosomes show pairing by the long, by the short or by both long and short arms. Assuming Lyon's hypothesis, the latter suggests that the Y segment transferred to the X is intercalar. With the light microscope, a negative image of the synaptonemal complex is evidenced.This work was supported by grants of the Brazilian Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) and Fundo Especial de Despesas do Instituto Butantan (FEDIB).We acknowledge Dr. N. Leon for his editorial suggestions. 相似文献
79.
Gremlin is the BMP antagonist required for maintenance of Shh and Fgf signals during limb patterning 总被引:13,自引:0,他引:13
During limb outgrowth, signaling by bone morphogenetic proteins (BMPs) must be moderated to maintain the signaling loop between the zone of polarizing activity (ZPA) and the apical ectodermal ridge (AER). Gremlin, an extracellular Bmp antagonist, has been proposed to fulfill this function and therefore be important in limb patterning. We tested this model directly by mutating the mouse gene encoding gremlin (Cktsf1b1, herein called gremlin). In the mutant limb, the feedback loop between the ZPA and the AER is interrupted, resulting in abnormal skeletal pattern. We also show that the gremlin mutation is allelic to the limb deformity mutation (ld). Although Bmps and their antagonists have multiple roles in limb development, these experiments show that gremlin is the principal BMP antagonist required for early limb outgrowth and patterning. 相似文献
80.
J. Beuth H. L. Ko M. Steuer G. Pulverer 《Cellular and molecular life sciences : CMLS》1993,49(6-7):547-550
Acute (hepatitis) and chronic (cirrhosis) liver injuries were experimentally induced in BALB/c-mice by administration of D-galactosamine and carbon tetrachloride, respectively. In both experimental liver diseases the incidence of hepatic tumor colonization of sarcoma L-1 was significantly reduced as compared to non-treated control animals. Thus, it seems that either dysfunction or loss of organ-characteristic lectins (galactosyl-specific hepatic lectins) prevented liver colonization. Histochemical staining of liver sections from D-galactosamine or carbon tetrachloride-treated mice with appropriate galactose-containing (neo) glycoproteins supported this hypothesis, since the lectin-dependent binding was greatly reduced as compared to sections from non-treated animals. 相似文献