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101.
Hakan Özkardeş Cankon Germiyanoğlu Ümit Kurt Levent Peşkircioğlu Uğur Altuğ Demokan Erol 《Pediatric surgery international》1995,10(7):488-491
Between 1983 and 1993, 41 patients underwent a first-stage Belt-Fuqua operation for penile hypospadias repair and 39 completed the second stage. Minor complications were observed after the first stage. The primary success rate following the second stage was 82%. Major complications noted after the second stage consisted mainly of fistula formation. The surgical technique is described and alternative methods are discussed. 相似文献
102.
Ahmet Nayir Alev Kadioĝlu Aydan Şirin Sevinç Emre Erdem Tonguç Ilmay Bilge 《Pediatric nephrology (Berlin, Germany)》1995,9(6):729-733
The primary disorders of 50 children with increased renal medullary echogenicity on renal ultrasound were studied; 28 girls and 22 boys aged from 1 month to 16 years were classified into four groups based on underlying disease and ultrasound findings. Group 1 was composed of 17 patients with distal renal tubular acidosis (34%); intense echoes throughout the pyramid were predominant. Group 2 consisted of 14 patients with vitamin D toxicity (28%) and an intense echogenic rim around the pyramids. Group 3 included 10 patients with different types of tubulopathies. A slight hyperechogenic rim around the sides and tip of the medullary pyramids was detected. Group 4 was made up of 9 patients with rare underlying conditions. Abdominal X-rays detected medullary calcinosis in only 12 (24%) of the total 50 patients. Ultrasonography appears to be an important tool in the early diagnosis of increased renal medullary echogenicity and medullary nephrocalcinosis. 相似文献
103.
P. E. Erkul O. M. Ariyürek D. Altinok A. Bakkaloĝlu E. Kotiloĝlu 《Pediatric radiology》1994,24(2):145-146
A 7-year-old girl with an unremarkable family history was admitted with complaints of diarrhea containing mucus and blood, abdominal pain, weight loss and fever for 10 months. Although her symptoms, physical examination and laboratory results were highly suggestive of inflammatory bowel disease, radiologic studies and colonoscopy demonstrated multiple colonic polyps. A bilateral and symmetric lamellar periosteal reaction and osteopenia were present on her extremity radiographs. The chest radiograph and thoracic CT scan were normal. The histologic nature of the polyps was determined as hamartoma. One month after subtotal colectomy, the patient's symptoms resolved and she gained 7kg in weight. The association of generalized juvenile polyposis and hypertrophic osteoarthropathy has previously been described in five cases; arteriovenous malformations were present in four of them. In our case the polyps were hamartomatous and localized in the colon, without associated arteriovenous malformation. 相似文献
104.
Age-Related Alterations in Antioxidant Enzymes, Lipid Peroxide Levels, and Somatosensory-Evoked Potentials: Effect of Sulfur Dioxide 总被引:4,自引:0,他引:4
P. Yargiçoğlu A. Ağar S. Gümüşlü S. Bilmen Y. Oğuz 《Archives of environmental contamination and toxicology》1999,37(4):554-560
The effect of sulfur dioxide (SO2) on somatosensory-evoked potentials (SEPs), thiobarbituric acid reactive substances (TBARS), and the activities of Cu,Zn-superoxide
dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) were investigated in young (3 months), middle-age (12
months), and old (24 months) Swiss male albino rats. Ten ppm SO2 was administrated to the animals of SO2 groups in an exposure chamber for 1 h/day × 7 days/week × 6 while control groups were exposed to filtered air in the same
condition. SO2 exposure caused increased levels of brain Cu,Zn-SOD activity and decreased levels of brain GSH-Px activity in all experimental
groups with respect to their corresponding control groups. Brain CAT activities were unaltered. Brain TBARS levels of all
SO2-exposed groups were significantly increased in comparison with their respective control groups. The mean latencies of P1, P2, and N2 components in the older group were either significantly different from the young or from the middle-age groups. The mean
latency of the N1 component in the older group and that of P1 and N1 in the middle-age group were significantly increased compared with the young group. SO2 exposure caused the prolongation of all components in the young group, whereas it affected only the P2 component in the middle-age group, but it did not result in any latency change in the older group in comparison with their
corresponding control groups.
Received: 22 December 1998/Accepted: 7 April 1999 相似文献
105.
Sarkarati B Cokuğraş AN Tezcan EF 《Comparative biochemistry and physiology. Part C, Pharmacology, toxicology & endocrinology》1999,122(2):181-190
Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with a procedure including ammonium sulfate fractionation (55-70%) with acid step at pH 4.5 and procainamide-Sepharose 4B affinity chromatography. The purified enzyme exhibited negative cooperativity with respect to butyrylthiocholine (BTCh) binding at pH 7.5. Ks was found to be 0.128 +/- 0.012 mM. Inhibition kinetics of the enzyme by Cd2+, Zn2+ and Al3+ were studied in detail. The 1/v vs 1/[BTCh] plots in the absence (control plot) and in the presence of different concentrations of cations intersected above 1/[BTCh]-axis. The data were analyzed by means of a nonlinear curve fitting program. The results demonstrated that all of the three cations are the linear mixed-type inhibitors of BChE. Ca2+ and Mg2+ had no effect on the enzyme activity in the experimental conditions. But when the enzyme was inhibited by 0.5 mM Cd2+ or Zn2+, Ca2+ and Mg2+ partially reactivated the inhibited allosteric form of BChE. Results were compared with data obtained from brain BChE purified from sheep. 相似文献
106.
In dentistry, acrylates have been used for preparing denture bases for 50 years. Although polymethylmethacrylates (PMMA) are known to be an ideal base material, they possess some undesirable mechanical properties, especially their impact strength and tensile strength, which appear to be unsatisfactory for some applications. Additives and fibers have therefore been used to enhance and improve these properties over the last two decades. The present article describes the mechanical properties, impact and tensile strength of PMMA reinforced with chopped ultra-high molecular weight polyethylene fiber (6 mm long). It was found that, although the processing involved for high loading of fibers into the PMMA was difficult, the resulting improvement of impact strength was substantial. 相似文献
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