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51.
Işcan M Ada AO Coban T Kapucuoğlu N Aydin A Isimer A 《Biological trace element research》2002,89(2):177-190
When male rats were given a single dose of cadmium (Cd) (3.58 mg CdCl2·H2O/kg, ip) 72 hr prior to sacrifice, the testicular 7-ethoxyresorufin O-deethylase (EROD) and glutathione S-transferase (GST) activities toward the substrates 1-chloro-2,4-dinitrobenzene (CDNB), 1,2-dichloro-4-nitrobenzene (DCNB),
ethacrynic acid (EAA), 1,2-epoxy-3-(p-nitrophenoxy)-propane (EPNP), and cumene hydroperoxide (CHPx) decreased significantly as compared to controls. Cd also inhibited
reduced glutathione (GSH) level while increasing the lipid peroxidation (LP) level significantly. When the animals were given
a single dose of nickel (Ni) (59.5 mg NiCl2·6H2O/kg, ip) 16 hr prior to sacrifice, significant decreases were observed in EROD and GST activities toward CDNB, EAA, EPNP,
and CHPx, and GSH level. No significant alterations were noted in DCNB GST activity and LP level by Ni. For the combined treatment,
rats received the single dose of Ni 56 hr after the single dose of Cd and were killed 16 hr later. In these animals, lesser
depressions were observed on EROD activity and LP level than those of Cd alone. The combination of metals significantly inhibited
GST activities and GSH level but not to a greater degree than noted by Cd or Ni alone. Plasma testosterone levels of Cd-,
Ni-, and combination-treated rats decreased significantly compared to controls. The strongest depression was achieved by Cd
alone. Cd, both alone and in combination with Ni, increased the tissue Ni uptake significantly. Ni, however, did not produce
such an effect on the tissue uptake of Cd in either case. Cd treatment caused interstitial edema and coagulation necrosis
in seminiferous tubules and also caused fibrinoidal necrosis in vascular endothelium. Ni treatment did not produce any pathological
testicular alterations compared to controls. Combined treatment produced fewer pathological alterations (i.e., only interstitial
edema) than that of Cd treatment. These results reveal that the combination of Cd and Ni does not have a synergistic effect
on testicular xenobiotic metabolizing enzymes, and in contrast, Ni has an ameliorating effect on pathological disturbances
caused by Cd alone in the rat testis. 相似文献
52.
53.
Regulation of virus-induced interferon-A genes 总被引:3,自引:0,他引:3
54.
Efficient and selective recognition of DNA by proteins is due to sequence-specific interactions with a target site and nonselective electrostatic interactions that promote the target's rapid location. If synthetic molecules could mimic these functions, they would render a wide range of chromosome sequences accessible to rationally designed probes. Here we describe conjugates between bispeptide nucleic acids (bisPNAs) designed to specifically recognize duplex DNA and peptides that have been designed to promote rapid sequence recognition. Peptide design was based on the surface of staphylococcal nuclease, a cationic DNA binding protein with low sequence selectivity. We observe that attachment of the designed peptide increases rates of strand invasion by 100-fold relative to unmodified bisPNA. The peptide can contain D-amino acids, increasing the likelihood that it will be stable in cell extract and inside cells. Binding of the conjugate containing the D-amino acid peptide occurred over a broad range of experimental conditions and was sensitive to a single mismatch. Strand invasion was efficient at neutral to basic pH, a wide range of temperatures (0-65 degrees C), and in the presence of up to 7 mM Mg(2+) and 100 mM Na(+) or K(+). Our data suggest that attachment of peptides that mimic cationic protein surfaces to PNAs can afford conjugates that mimic the rapid and selective binding that characterizes native DNA binding proteins. Rapid strand invasion over a wide range of experimental conditions should further expand the utility of strand invasion by PNAs. 相似文献
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57.
The simple and effective choice for treatment of chronic calcaneal osteomyelitis: neurocutaneous flaps 总被引:9,自引:0,他引:9
Yildirim S Gideroğlu K Aköz T 《Plastic and reconstructive surgery》2003,111(2):753-60; discussion 761-2
The authors describe their experience with the use of distally based saphenous and sural neurofasciocutaneous flaps for the treatment of calcaneal osteomyelitis in nine cases. Aggressive débridement of all nonviable and poorly vascularized tissue and coverage with a distally based neurofasciocutaneous flap were coupled with a thorough antibiotic course in all cases. The deepithelized peripheral parts of all flaps were buried in the bone cavities after bone débridement. Follow-up periods ranged from 15 to 27 months. All flaps survived completely. All of the wounds except one healed completely. These flaps have adequate blood flow for the management of chronic bone infections. They also have many advantages, such as easy quick elevation, short operative time, and acceptable donor-site morbidity. Moreover, patients treated with neurocutaneous flaps do not require debulking procedures or special shoes. Reconstruction with neurocutaneous flaps after radical débridement is a versatile alternative to the use of local or distant muscle flaps and calcanectomy procedures for patients with osteomyelitis of the os calcis. 相似文献
58.
Reconstruction of the weight-bearing surface of the foot with nonneurosensory free flaps 总被引:3,自引:0,他引:3
Sönmez A Bayramiçli M Sönmez B Numanoğlu A 《Plastic and reconstructive surgery》2003,111(7):2230-2236
Neurotized fasciocutaneous flaps and split-skin grafted muscle flaps are the most frequently used free flap alternatives for the reconstruction of weight-bearing surfaces of the foot. An objective comparison of the innate characteristics of these two flap types, with respect to long-term stability, has not been possible because sensory reinnervation in the fasciocutaneous flaps has been a confounding factor. This study compares nonsensate fasciocutaneous flaps (n = 9) with nonsensate split-skin grafted muscle flaps (n = 11), with mean follow-up periods of 34.3 and 31.3 months, respectively. Patients completed a form that included questions regarding degree of pain at the operative site, presence of ulcers, ability to wear normal shoes, employment status, and time spent standing on foot. Touch and deep sensation were evaluated with Semmes-Weinstein and vibration tests, respectively. Significantly less pain and less ulceration (p < 0.05) were observed in the fasciocutaneous group. Semmes-Weinstein monofilament tests revealed poorer results with split-skin grafted muscle flaps, compared with fasciocutaneous flaps. These results indicate that even if the sensory protection of fasciocutaneous flaps is not considered, these flaps have superior properties, compared with split-skin grafted muscle flaps. 相似文献
59.
The isolation, structural elucidation, and antiprotozoal activities of habropetaline A, a novel naphthylisoquinoline alkaloid from Triphyophyllum peltatum, are described. This alkaloid had previously only been identified on line, by the LC-MS/MS-NMR-CD triad, in the crude extract of the rare and difficult-to-provide related plant species Habropetalum dawei, whose small quantities available had not permitted to isolate the compound. As predicted by quantitative structure-activity relationship (QSAR) investigations, habropetaline A exhibits strong antimalarial activity against Plasmodium falciparum, while it is inactive against other protozoal pathogens (Trypanosoma brucei rhodesience, T. cruzi, and Leishmania donovani). 相似文献
60.