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191.
Arai K Toh S Tsubo K Nishikawa S Narita S Miura H 《Plastic and reconstructive surgery》2002,109(7):2301-2306
The clinical results and complications of the vascularized fibular graft for the reconstruction of various long bone defects were reviewed in 60 cases. Bony reconstruction was achieved in 57 of the 60 cases; however, various postoperative complications occurred in 54 percent of the cases. One case of arterial thrombosis of an anastomosed vessel and nine cases of venous congestion of the monitoring flap occurred in the early postoperative periods. The authors managed the nine cases of venous congestion of the flap conservatively, and all flaps survived. Partial necrosis of the flap was noted in eight of these nine cases, but additional surgical intervention was required in only four cases. Treatment included a gastrocnemius musculocutaneous flap in one case and a full-thickness skin graft in three cases. The vascularized fibula survived and bony fusion was achieved in all of these cases. The one case of arterial thrombosis resulted in graft failure due to a delay in the decision to perform a thrombectomy. Graft fracture occurred in 13 cases as the mechanical stress to the graft increased. In two cases of femoral reconstruction, graft fracture occurred during dynamization of the graft, despite the use of an Ilizarov external fixator. Correct alignment between the recipient bone and the external fixator is a prerequisite to preventing graft fracture. Vascularized fibular grafting offers the patient a great deal of benefit; however, this graft has a concomitant high risk of complications. Great attention to detail must be paid to prevent postoperative complications. 相似文献
192.
193.
Med was found as a positive regulator for comK, a master regulator for late competence genes. It was found by Western analysis that the ComK level was decreased in a med mutant. Experiments using an alkaline phosphatase fusion with Med and Western analysis of Med were done because a putative lipo-modification signal is found at the N-terminus of Med. The results obtained are consistent with the localization of Med at the cell surface. An implication of the cell-surface localization of Med is discussed in terms of comK regulation. 相似文献
194.
Hashimoto T Nonaka Y Minato K Kawakami S Mizuno M Fukuda I Kanazawa K Ashida H 《Bioscience, biotechnology, and biochemistry》2002,66(7):1610-1614
To investigate the effects of lentinan from Lentinas edodes and polysaccharides from Agaricus blazei (ABPS) on the expression of cytochrome P450s (CYPs), lentinan (10 mg/kg/day) or ABPS (200 mg/kg/day) was administered to female BALB/c mice four times every other day by intraperitoneal injection. Lentinan and ABPS suppressed both the constitutive and 3-methylcholanthrene-induced CYP1A expression and ethoxyresorufin-O-deethylation activity in the liver. 相似文献
195.
We examined morphological changes in the first-formed protoxylem vessels in Arabidopsis seedlings. Between 2.5 and 8 days after imbibition, mean hypocotyl and root length increased 1.52 and 23.3 times, respectively. In the 2.5-day-old seedlings, two continuous protoxylem vessels were present in the hypocotyl-root axis. In the 8-day-old upper hypocotyls, six protoxylem vessels were observed, and in the lower hypocotyls, four protoxylem vessels and one or two metaxylem vessels were observed. In the 8-day-old roots, there were two protoxylem vessels and two or three metaxylem vessels. Two protoxylem vessels in the hypocotyls connected to two metaxylem vessels in the roots of 8-day-old seedlings. At the 0.3-mm part below the hypocotyl-root boundary, the mean intervals of neighboring annular secondary wall thickenings in protoxylem vessels in 8-day-old roots were 12.9% larger than those in 2.5-day-old roots. In more apical parts of 8-day-old roots, the mean intervals fluctuated between 1.71 and 2.29 microm. In 8-day-old seedlings, metaxylem vessels were formed between 0.4 mm above the hypocotyl-root boundary and 17 mm below the boundary. The intervals in these regions were not extended so much as protoxylem vessels were collapsed. The first-formed protoxylem vessels presumably retain their water-conductive function after metaxylem formation. 相似文献
196.
Seko T Kato M Kohno H Ono S Hashimura K Takenobu Y Takimizu H Nakai K Maegawa H Katsube N Toda M 《Bioorganic & medicinal chemistry letters》2002,12(17):2267-2269
This study was performed to determine the structure-activity relationships (SAR) of L-cysteine based N-type calcium channel blockers. Basic nitrogen was introduced into the C-terminal lipophilic moiety of L-cysteine with a view toward improvement of its physicochemical properties. L-Cysteine derivative 9 was found to be a potent and selective N-type calcium channel blocker with IC(50) of 0.33 microM in calcium influx assay using IMR-32 cells and was 15-fold selective for N-type calcium channels over L-type channels. Compound 9 showed improved oral analgesic efficacy in the rat formalin induced pain model and the rat chronic constriction injury (CCI) model, which is one of the most reliable models of chronic neuropathic pain, without any significant effect on blood pressure or neurological behavior. 相似文献
197.
Goto DB Ogi M Kijima F Kumagai T van Werven F Onouchi H Naito S 《Genes & genetic systems》2002,77(2):89-95
Met-overaccumulating mutants provide a powerful genetic tool for examining both the regulation of the Met biosynthetic pathway and in vivo developmental responses of gene expression to altered Met levels. We have previously reported the identification of two Arabidopsis thaliana Met over-accumulation (mto) mutants, mto1-1 and mto2-1, that carry mutations in the genes encoding cystathionine gamma-synthase (CGS) and threonine synthase (TS), respectively. A third mutant, mto3-1, has recently been reported to carry a mutation in the gene encoding S-adenosylmethionine synthetase 3 (SAMS3). Here, we report the isolation of a new ethionine-resistant A. thaliana mutant that over-accumulates soluble Met approximately 20-fold in young rosettes. The causal mutation was determined to be a single, recessive mutation that was mapped to chromosome 3. Sequence analysis identified a single nucleotide change in the gene encoding SAMS3 that was distinct from the mto3-1 mutation and altered the amino acid sequence of the enzyme active site. This mutation was therefore referred to as mto3-2. Although Met over-accumulation in the mto3-2 mutant was similar to that in the mto2-1 mutant, CGS mRNA levels did not respond to the mto3-2 mutation and were similar to that in equivalent wild-type plants. 相似文献
198.
Hori H Nagasawa H Ishibashi M Uto Y Hirata A Saijo K Ohkura K Kirk KL Uehara Y 《Bioorganic & medicinal chemistry》2002,10(10):3257-3265
A series of 2-hydroxyarylidene-4-cyclopentene-1,3-diones were designed, synthesized, and evaluated with respect to protein tyrosine kinase (PTK) inhibition, mitochondrial toxicity, and antitumor activity. Our results show that the cyclopentenedione-derived TX-1123 is a more potent antitumor tyrphostin and also shows lower mitochondrial toxicity than the malononitrile-derived AG17, a potent antitumor tyrphostin. The O-methylation product of TX-1123 (TX-1925) retained its tyrphostin-like properties, including mitochondrial toxicity and antitumor activities. However, the methylation product of AG17 (TX-1927) retained its tyrphostin-like antitumor activities, but lost its mitochondrial toxicity. Our comprehensive evaluation of these agents with respect to protein tyrosine kinase inhibition, mitochondrial inhibition, antitumor activity, and hepatotoxicity demonstrates that PTK inhibitors TX-1123 and TX-1925 are more promising candidates for antitumor agents than tyrphostin AG17. 相似文献
199.
Phosphoinositide turnover is closely connected to modulation of synaptic function and is part of an important second messenger-producing system. New radioligands for imaging second messenger systems by positron emission tomography have been developed: carbon-11-labeled 1,2-diacylglycerols. The theoretical background of second messenger imaging is described in detail and the relation between the biologically active compounds and potential tracers for imaging second messenger systems is discussed. We report informative findings on postsynaptic biological responses in the living human brain of healthy normal subjects and with various diseases. 相似文献
200.
Reported crystallographic data and calculated molecular models indicated that chlorophyll (Chl) a and bacteriochlorophyll (BChl) a tend to bind the fifth ligand on the side of the macrocycle where the C132-(R)-methoxycarbonyl moiety protrudes (denoting the ‘back’ side). The crystal structures of 34 photosynthetic proteins possessing
(B)Chl cofactors revealed that most of Chl a and BChl a (and b) are coordinated by any peptidyl residue (e.g., histydyl-imidazolyl group), peptidyl backbone or water from the ‘back’ side.
Almost all the cofactors that bind a water molecule as the fifth ligand in these proteins have a ‘back’ configuration. Theoretical
model calculations for methyl chlorophyllide a (MeChlid a) and methyl bacteriochlorophyllide a (MeBChlid a) bound to an imidazole molecule indicated that the ‘back’ side is energetically favored for the ligand binding. These results
are consistent with the fact that ethyl chlorophyllide a (EtChlid a) dihydrate crystal consists of the ‘back’ complex. The modeling also showed that both removal and stereochemical inverse
of the C132-methoxycarbonyl group affect the relative stability between the ‘back’ and ‘face’ complexes. The effect of the C132-moiety on the choice of the macrocycle side for the ligand binding is discussed in relation to the function of P700.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献