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951.
PURPOSE: We report a straightforward surgical technique for the correction and anatomical alignment of the skin in patients with various degrees of buried penis. MATERIALS AND METHODS: A combined series of 74 patients 7 months to 10 years old who were treated for buried penis at 2 institutions during a 7-year period. Patients presented with various symptoms, including balanitis, urinary tract infection, painful voiding, ballooning of the foreskin and urinary retention. In 29 patients (38%) trapped penis was due to previous circumcision. In our estimation the major anatomical defect in buried penis is an insufficient attachment of the dartos fascia and penile skin to Buck's fascia. Our technique involves making a circumferential incision of the inner preputial skin layer proximal to the corona, unfurling it from the shaft skin and leaving a coronal collar of approximately 1 cm. The annular band that usually constricts the corpora on retraction of the penile skin is incised, and the remaining proximal penile skin and dartos fascia are dissected off Buck's fascia proximally to the base of the penis. The penile dermis is sutured to the lateral aspect of the tunica albuginea at the penopubic junction and mid shaft of the penis. This technique restores normal anatomical relationships with excellent cosmetic results and negligible complications. RESULTS: At a median 5-year followup cosmesis was excellent in all cases. Two patients with micropenis who required revision responded to endocrine therapy. CONCLUSIONS: Excellent cosmetic results were obtained in all cases using this surgical technique. 相似文献
952.
L Parnetti DT Lowenthal O Presciutti GP Pelliccioli R Palumbo G Gobbi P Chiarini B Palumbo R Tarducci U Senin 《Canadian Metallurgical Quarterly》1996,44(2):133-138
AIM: To study whether the effect of captopril (Cap) on vascular structure and function may be seperated from its effect on blood pressure. METHODS: Captopril treatment (group Cap A and B, 20 and 100 mg.kg-1.d-1) was given to SHR rats during pregnancy, weaning, and up to 16 wk of age. Study performed at 40 wk. Blood pressure (BP) was measured by tail-cuff sphygmomanometer, and wall/lumen ratio of mesenteric artery 3rd grade branch was assessed by morphometric assay. Resistance vessel properties were determined by hindquarter perfusion pressure responses to incremental doses of phenylephrine, in the presence of N omega nitro-L-arginine methyl ester (L-NAME) or the L-arginine, the precursor of nitric oxide synthesis. RESULTS: Both doses of Cap prevented hypertrophy of blood vessels to an extent comparable to that of the untreated WKY rats (wall/lumen ratio of mesenteric artery, Cap A: 0.38 +/- 0.08, Cap B: 0.29 +/- 0.05 vs WKY: 0.34 +/- 0.11, P > 0.05, respectively). The parameters derived from hindquarter perfusion pressure curves in Cap treated group were almost identical to that of WKY, significantly different from that of untreated SHR (EC50, Cap B 4.05 +/- 2.58 vs SHR 1.15 +/- 0.96 mL.L-1, P < 0.01; vs WKY 5.13 +/- 1.97 mL.L-1, P > 0.05). Addition of L-NAME or L-arginine in the perfusate augmented or attenuated the vasoconstriction responses in the Cap treated group. CONCLUSION: Cap initiated from intrauterine period normalized the vascular structure and vasoconstrictive responses in SHR when BP still sustained at a higher level vs WKY. 相似文献
953.
GP Teitelbaum MA Lefkowitz SL Giannotta 《Canadian Metallurgical Quarterly》1998,50(4):300-11; discussion 311-2
954.
MA Sinatra GP Young DJ St John D Blake S Ratnaike 《Canadian Metallurgical Quarterly》1998,13(4):396-400
The effects of chromium (Cr) supplementation on diet-induced insulin resistance produced by feeding a high-fat, low-Cr diet were studied in rats to ascertain the role of Cr in insulin resistance. Wistar male rats were maintained for 16 weeks after weaning on a basal diet containing 40% lard, 30% sucrose, and 25% casein by weight and adequate vitamins and minerals without added Cr (-Cr). Fasting levels of insulin, glucose, and triglycerides and the responses during an intravenous glucose tolerance test (IVGTT) were compared as indices of insulin resistance and the effectiveness of dietary Cr. IVGTTs and blood sampling for data analyses were performed over a 40-minute period after IV glucose injection (1.25 g/kg body weight) in overnight-fasted animals under pentobarbital anesthesia (40 mg/kg body weight). All animals were normoglycemic (-Cr, 109 +/- 3 mg/dL; +Cr, 119 +/- 5), with fasting insulin levels elevated in the -Cr group (65 +/- 10 microU/mL) versus the +Cr group (31 +/- 4 microU/mL). Increases in plasma triglycerides in the -Cr group were not significant. Following glucose injection, the rate of glucose clearance was lower in the -Cr group (1.74 +/- 0.22 v2.39 +/- 0.11%/min), and 40-minute glucose areas in the -Cr group tended to be higher than in the +Cr group. The insulin response to glucose injection was 20% higher in the -Cr group. Forty-minute plasma triglyceride areas were lower in +Cr rats (875 +/- 62 v 1,143 +/- 97 mg/dL.min in -Cr rats). These data demonstrate that the insulin resistance induced by feeding a high-fat, nutrient-stressed diet is improved by Cr. 相似文献
955.
A rare case of primary malignant melanoma of the oral cavity is reported and a literature review of etiopathogenesis, biological bases and prognosis is made. The hypotheses to explain the very severe prognosis of malignant melanoma of the oral cavity with respect to that of skin are discussed. The therapeutic approaches are described as well as the frequent difficulty to perform them in relation to the anatomical region and the wide extension of the tumoral lesion. 相似文献
956.
Topical directions of developing the medical expert systems (MES) are considered. The problems to be solved by using programming and informational means as part of MES are discussed. A classification of the knowledge of expert physicians who directly deal with decision making is proposed. The characteristics of the developed MES well appreciated by the results of their operation are given. They show new trends associated with the update of medical knowledge and the developmental level of information technologies. 相似文献
957.
E Andreadou C Yapijakis GP Paraskevas P Stavropoulos C Karadimas VP Zis P Davaki N Karandreas M Rentzos C Tsakanikas D Vassilopoulos C Papageorgiou 《Canadian Metallurgical Quarterly》1996,243(3):225-230
Cluster outbreaks of lymphoma and leukemia have been associated with viral infections in many species including humans, cattle, and cats. This study describes epidemiological, clinical, and pathological features of cluster outbreaks of lymphoma in multiferret households and examines and compares the Aleutian disease virus (ADV) and feline leukemia virus (FeLV) status of cases, ferrets at risk, and controls. Three ferret groups with 21 cases of histologically diagnosed lymphoma (12.6% cumulative incidence) and their cohabitants (n = 35) were examined and compared with three control groups (n = 52) of cohabitating ferrets without lymphoma. A familial distribution was observed in one group but most cases were not consanguinous. Ferrets greater than 3 years of age developed chronic disease in two of the groups and 2-year-old adults had acute disease in the remaining group. Lymphocytosis, splenomegaly, and lymphadenopathy were prominent features. Histologically, predominantly small noncleaved cell and polymorphous lymphoid lesions were observed. All of the ferrets with lymphoma that were tested for ADV and FeLV using serology or PCR were negative. The rate of ADV antibody among cases or ferrets at risk was not significantly different from controls. None of the cluster ferrets were seropositive for FeLV p27 antigen using a monoclonal ELISA. Infection with a novel ferret virus is suspected, but an etiological agent has not yet been identified. 相似文献
958.
MF Denissenko TB Koudriakova L Smith TR O'Connor AD Riggs GP Pfeifer 《Canadian Metallurgical Quarterly》1998,17(23):3007-3014
Sequence-dependent formation and lack of repair of polycyclic aromatic hydrocarbon-induced DNA adducts correlates well with the positions of p53 mutational hotspots in smoking-related lung cancers (Denissenko et al, 1996, 1998). The mycotoxin aflatoxin B1 (AFB1) is considered to be a major causative agent in hepatocellular carcinoma (HCC) in regions with presumed high food contamination by AFB1. A unique mutational hotspot, a G to T transversion at the third base of codon 249 of the p53 gene is observed in these tumors. To test whether a selectivity of AFB1 adduct formation is related to this peculiar mutational spectrum, we have mapped AFB1-DNA adducts at nucleotide resolution using ligation-mediated PCR and terminal transferase-dependent PCR. Human HepG2 cells were exposed to AFB1 metabolically activated in the presence of rat liver microsomes. Significant adduct formation was seen at the third base of codon 249. However, this was not the major site of AFB1 adducts and strong adduction was also observed at codons 226, 243, 244, 245 and 248 in exon 7 of the p53 gene and at several codons in exon 8. The damage at codon 249 does not consist of a unique abasic site or ring-opened aflatoxin B1 adduct but rather is consistent with the principal N7-guanine adduct of AFB1. Time course experiments indicate that, under the conditions used, AFB1 adducts are not removed in a strand-selective manner and adduct removal from the third base of codon 249 proceeds at a relatively fast rate (50% in 7 h). The incomplete correspondence between sites of persistent AFB1 damage and the specific codon 249 mutation suggests that AFB1 may not be involved in mutation of this site or that additional mechanisms such as parallel infection with hepatitis B virus may be required for selection of codon 249 mutants in HCC. 相似文献
959.
960.
V Fischer U Schmitt H Weigmann B Von Keller S Reuss C Hiemke N Dahmen 《Canadian Metallurgical Quarterly》1998,22(7):1129-1139
1. Adult, female rats were treated orally for 23 days with 1.6 mg/kg haloperidol or 36 mg/kg clozapine per day, to study chronic effects of the two neuroleptics. 2. At five time points during the neuroleptic treatment, animal behavior was recorded in an open field and locomotive activity was analysed. At the end of the experiment, rats were decapitated, blood samples were collected and serum concentrations of haloperidol and clozapine were determined by a radioreceptor or HPLC assay, respectively. RNA was isolated from each brain, without cerebellum, and subjected to differential RNA display. 3. Mean serum concentrations were 8 ng/ml for haloperidol and 21 ng/ml for clozapine. Analysis of open field behavior showed that haloperidol and clozapine decreased the total distance moved and the velocity as measures of the overall activity, whereas the number of rearings and the number of entries into the center, reflecting risk assessment behavior, were differentially affected. Three neuroleptic-regulated gene fragment bands were identified in differential RNA display experiments. Two gene fragments of 281 bp and 266 bp were sequenced. 4. We conclude that our study design that used behavioral, pharmacokinetic and molecular analysis increase the likelihood of finding relevant molecular events underlying the pharmacotherapeutic effects of neuroleptics in animal models. 相似文献