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91.
92.
The circulatory anatomy of the iliofemoral region was elucidated by doing detailed angiography in 50 cases, and we classified the vessels into 4 types. In most cases, the s.c.i.a. predominated over the s.i.e.a. Therefore, it is probably better to plan free flaps supplied by this artery. This vessel usually arises approximately two or three fingerbreadths inferior to the intersection of the femoral artery and the inguinal ligament, and the skin flap should be designed in the area inferior and parallel to the inguinal ligament.  相似文献   
93.
1. Circulating concentrations of iodothyronines, luteinizing hormone(LH), estradiol(E2), progesterone and corticosterone were measured in hens before, during, and after a forced molt induced by fasting. 2. Corticosterone increased at the onset of molt, peaked at the maximal molt and returned to pre- and post-molt levels. LH, E2 and progesterone declined during the molt, and the decline was coincident with the cessation of egg production. 3. Thyroxine(T4), triiodothyronine (T3) and reverse triiodothyronine(rT3) increased during the molt. The increases of T4 and T3 were not abolished even if the forced molt was conducted in mild weather.  相似文献   
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96.
Using ethyl methane sulfonate (EMS) treatment of the seeds ofline SGE, a new mutant of pea (Pisum sativum L.) with alterationsin root development was obtained. The mutant phenotype dependson the density of the growth substrate: on sand (a high densitysubstrate) the mutant forms a small compact curly root systemwhereas on vermiculite (a low density substrate) differencesbetween the root systems of the mutant and wild type plantsare less pronounced. Genetic analysis revealed that the mutantcarries a mutation in a new pea gene designedcrt (curly roots).Gene crt has been localized in pea linkage group V. The mutantline named SGEcrt showed increased sensitivity to exogenousauxin and an increased concentration of endogenous indole-3-aceticacid (IAA) in comparison with the wild type line SGE. Copyright2000 Annals of Botany Company Pisum sativum L., root development, garden pea mutant, curly roots, auxin, environmental stimulus response  相似文献   
97.
Membrane-bound and secreted IgA contain structurally different alpha-chains   总被引:3,自引:0,他引:3  
Three different forms of alpha-chains are synthesized by BF0.3 and 615.2, two cloned cell lines derived from the murine B lymphoma 1.29. The three forms of alpha-chains differ in size, pI, cellular location, and rate of turnover. They were identified by means of lactoperoxidase-catalyzed radioiodination, internal 14C or 35S labeling, and immunofluorescence techniques as membrane-bound(alpha m), secreted (alpha s), and intracellular (alpha ic) proteins. Comparison of immunoglobulin products of the two lymphoma lines with those of a hybridoma cell line, Id 150, which secretes IgA of the 1.29 idiotype but lacks membrane IgA, confirmed the assignments of alpha m, alpha s, and alpha ic. Results of biosynthetic labeling of BF0.3, 615.2, and Id 150 in the presence and absence of tunicamycin suggest that the difference in m.w. and charge observed between alpha m and alpha s can be attributed to differences in primary amino acid structure rather than different degrees of glycosylation.  相似文献   
98.
Cell division in fertilized sea urchin eggs was reversibly inhibited when the ketoaldehyde phenyl glyoxal (PG) at a concentration of 0.1 mM was added to eggs for ten minutes prior to the formation of the mitotic spindle. We investigated whether inhibition of mitosis was due to PG binding to the cell surface (as previously suggested by Stein and Berestecky, '74) or to some intracellular effect. When 14C-PG was added to eggs, label was readily taken up into the egg cytoplasm; very little label was associated with the egg surface. In the cytoplasm PG combined with equimolar amounts of reduced glutathione (GSH), decreasing the levels of cellular GSH to less than 15% of normal and accounting for at least 50% of the PG taken up by eggs. The concentrations of oxidized and protein-bound glutathione were unaffected by PG treatment. We showed that glyoxalase enzymes were present in sea urchin eggs and were capable of metabolizing the PG-GSH complex, thereby restoring GSH to normal levels after PG was removed from the sea water. Though some other effect of PG cannot be ruled out, the major fate of PG in eggs was to combine with GSH, and the transient decrease in GSH which resulted could lead to inhibition of mitosis. While other reports (Nath and Rebhun, '76; Oliver et al., '76) have shown that reagents which oxidize GSH disrupt microtubule-related events, our results showed that such inhibition could be caused by decreased GSH levels alone.  相似文献   
99.
Toxin gamma is a basic, low-molecular-weight, neurotoxic protein, isolated from the venom of the Brazilian scorpion, Tityus serrulatus. Raman spectra (400-1800 cm-1 region) of this toxin in both the lyophilized state and in 0.1 M acetate buffer (pH 4.5) and the infrared spectrum (700-4000 cm-1 region) of a solid film were investigated. From the vibrational spectra, it can be concluded that the polypeptide backbone of toxin gamma consists of a mixture of the different secondary structures, with predominance of beta-sheet, followed by unordered structure and alpha-helix, with some evidence of beta-turn structures. The four disulfide bridges assume the gauche-gauche-gauche conformation of the CCSSCC fragments. The intensity ratio of the doublet at 853 and 828 cm-1 suggests that four out of the five tyrosine residues are exposed. The three tryptophan residues are exposed on the surface, and the single methionine residue assume the gauche-gauche conformation. Toxin gamma retains full activity in the pH 4.5-7.5 range, but is almost completely inactivated at pH 11.5.  相似文献   
100.
H. Haibach  Y. W. Yesus  J. J. Doggett 《CMAJ》1984,130(9):1165-1166
A 46-year-old man with pentazocine-induced agranulocytosis is described. In previously reported cases of a complete absence of mature neutrophils in the peripheral blood and bone marrow the patients had undergone marrow-depressing treatment with radiation and antineoplastic drugs. This case is unique in that the patient had complete agranulocytosis without predisposing factors.  相似文献   
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