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871.
Twelve adult, bilaterally vasectomized dogs were used to compare two different procedures for reuniting the severed vas deferens. Approximately 5 months postvasectomy six dogs had vasovasostomies utilizing Silastic stents and the vasa deferentia of six additional dogs were rejoined with intravasal chromic stents. Ejaculates were subsequently obtained at 2-week intervals and evaluated for sperm count, motility, viability, and seminal ion concentrations. All of the dogs in which Silastic had been utilized as the stent had sperm reappear in the ejaculate, whereas only 40% of the dogs in which chromic catgut had been utilized had reappearance of spermatozoa. The over-all quality of the ejaculate was also better in the animals in which Silastic had been utilized. Testicular and epididymal histology was normal in most dogs of both groups, but three of the dogs with chromic stents in which the anastomosis had not been a success had abnormal histology, with reduced numbers of spermatocytes, spermatids, and spermatozoa. The data suggest that Silastic stents are better than chromic stents for vas reanastomosis. They also suggest that some dog testes react negatively to vasectomy and do not recover by 1 year postvasectomy when vas patency is not reversed. 相似文献
872.
The Beck Anxiety Inventory was administered to 105 outpatients between 13 and 17 years old who were diagnosed with various types of psychiatric disorders. A principal factor analysis was performed, and two factors were found representing subjective and somatic symptoms of anxiety. The item compositions of these factors were comparable to those previously described for adolescent inpatients. The results are discussed as supporting the use of the inventory for evaluating self-reported anxiety in outpatient adolescents. 相似文献
873.
AT Karapetian GA Terzikian NM Megrabian SG Arutiunian PO Vardevanian 《Canadian Metallurgical Quarterly》1995,29(4):841-847
The theory of the cooperative transition of DNA.ligand complexes have been developed, in which a model was implied where the multimodal ligands simultaneously interacted with DNA. Obtained formula express the dependence of the experimentally estimated values of the changes of transition point and width of transition on the concentration of the ligands. These expressions make possible to obtain the thermodynamic parameters of the interaction of the multimodal ligands with DNA (binding constants, number of base pairs corresponding to one binding site of DNA etc.) by comparing the theoretical and the experimental data. 相似文献
874.
The incidence of epiploic entrapment of the small intestine in horses undergoing celiotomy for colic was 5%. The condition was more prevalent in older (mean 9.81 years) gelding and Thoroughbred horses. Preoperative peritoneal protein level was a good prognostic indicator as it was significantly greater in the nonsurvivor (39.4 +/- 5.10) group than in the survivor group (26.6 +/- 14.0) (P<0.05). Abdominal ultrasonography allowed earlier diagnosis and surgical intervention in nonpainful cases with inconclusive rectal findings. Surgery was completed in 46 horses and 44 horses recovered from anaesthesia. Nine horses were either subjected to euthanasia in surgery (7 horses) or died in recovery (2 horses). Repeat laparotomies were pursued in 27% (12/44) of the horses. Seven horses (16%) showed post operative adynamic ileus which was the most common post operative complication. The incidence (6%) of adhesion formation was lower than previously reported. Other post operative complications included gastric ulceration, liver disease, diarrhoea and weight loss. Short and long term survival rates were 79% (35/44) and 70% (31/44) respectively. Improved rates were attributed to earlier referral and diagnosis and prompt surgical intervention. The aggressive use of repeat celiotomy and a more effective treatment of the endotoxic horse in the perioperative period contributed to survival. 相似文献
875.
AT Scher 《Canadian Metallurgical Quarterly》1980,58(1):27-30
Hyperextension injuries of the cervical spine, previously considered rare, are now being diagnosed more frequently. The radiological features of these injuries are subtle, and their significance as an indication of hyperextension trauma is often overlooked. Six different hyperextension injuries are described, illustrating the varying radiological appearances. 相似文献
876.
BS Baker JB Boyd AT Carpenter MM Green TD Nguyen P Ripoll PD Smith 《Canadian Metallurgical Quarterly》1976,73(11):4140-4144
Recombination-defective meiotic mutants and mutagen-sensitive mutants of D. melanogaster have been examined for their effects on meiotic chromosome behavior, sensitivity to killing by mutagens, somatic chromosome integrity, and DNA repair processes. Several loci have been identified that specify functions that are necessary for both meiotic recombination and DNA repair processes, whereas mutants at combination and DNA repair processes, whereas mutants at other loci appear to be defective in only one pathway of DNA processing. 相似文献
877.
The effects of vasectomy on the development and maintenance of spermatogenesis was studied using immature and mature dog testes. Bilateral vasectomy in immature dogs delayed the development of advanced spermatocytes, spermatids, and spermatozoa for about 3 months postsurgery. Spermatogenesis appeared to be recovered to control levels by 4 months postvasectomy. Spermatogenesis in mature dogs was also altered after bilateral vasectomy. Decreased numbers of advanced spermatocytes as well as maturation arrest was observed by 3 weeks postvasectomy. Seminiferous tubule cell layers quickly decreased to one to three layers as the lumina became occluded with sloughed cells by 3 to 6 weeks postvasectomy. Recovery in terms of the numbers of spermatocytes, spermatids, and spermatozoa was evident by 13 weeks postvasectomy, although occasional dog testes did not recover and appeared to be more sensitive to vasectomy-induced damage. It thus appears that vasectomy temporarily inhibits both the development and maintenance of spermatogenesis in immature as well as mature dog testes. Spermatogenesis does recover but may be maintained at somewhat lower levels after vasectomy. Changes are rapid in onset and take several weeks to be reversed. Some dog testes appear to be more sensitive to the damage and it may be irreversible in these testes. 相似文献
878.
A cytogenetic survey was carried out on 200 patients with mental retardation and multiple congenital anomalies, and on 200 normal adult controls. Patients with a known syndrome were excluded from the survey. Chromosome analyses were carried out on 'blind-coded' slides using the ASG banding technique as the routine stain. After the initial analyses (at least 15 cells per person) the slides were decoded, destained and reused for C and Q band polymorphism studies. Five major chromosome abnormalities were detected in the patient group during the survey. They included three patients with de novo, apparently balanced, reciprocal translocations, karyotypes 46,XY,rcp(3;16)(q21;p12); 46,XX,rcp(5;8)(p15;q22); and 46,XX,rcp(5;12)(p11;q24); one with karyotype 47,XX,+mar and one with karyotype 46,XX,der(13),t(13;?)(q34;?). One additional patient whose karyotype in lymphocytes was 46,XX,inv(9)(p11;q13) was found to have a mosaic karyotype 46,XX,inv(9)(p11;q13)/46,XX,inv(9) (p11;q13), der(12),t(12;?)p13;?) in cultured skin fibroblasts. None of the 200 controls had a major chromosome abnormality. From the combined results of this and previous surveys it is now apparent that about 6.2% of the unclassifiable mentally retarded patients with three or more congenital anomalies and about 0.7% of the controls reveal major chromosome abnormalities. 相似文献
879.
880.