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81.
DA Partrick  DD Bensard  FM Karrer  SZ Ruyle 《Canadian Metallurgical Quarterly》1998,33(7):1090-2; discussion 1093-4
BACKGROUND/PURPOSE: Herniorrhaphy is the most common general surgical procedure performed on children, and hernia sac material is one of the most common tissue specimens microscopically examined in the authors' surgical pathology laboratory. The risk of accidental vas deferens ligation has prompted the recommendation that all hernia sacs be examined pathologically. The authors hypothesized that the incidence of unrecognized vas deferens or epididymis ligation is actually very low and may not warrant routine pathological examination of all pediatric hernia sacs. METHODS: Over a 3-year period (1994 to 1996), pathology reports from all hernia repairs at the authors' institution were reviewed. A total of 1,494 inguinal hernia sacs were pathologically evaluated from 1,077 pediatric patients (417 were bilateral). Pathological diagnoses not affecting clinical management (ie, chronic inflammation, irritated hernia sacs, embryonal remnants, adrenal cortical rests) were classified as incidental findings. Identification of true vas deferens was classified as a positive finding. RESULTS: The study population had a mean age of 3.9 +/- 0.1 years and 963 (89%) were boys. The incidence of vas deferens injury from herniorrhaphy was found to be 0.13% (2 of 1,494), and these were recognized by the pediatric surgeon in the operating room. CONCLUSIONS: When vas deferens injury is suspected, the sample should always be sent to the pathology department for confirmation. However, no occult carcinoma or other pathology was identified, and the remainder of the histological findings did not change the clinical treatment of any child. Given a fixed cost of pathological analysis, elimination of routine hernia sac examination may result in substantial annual savings. Therefore, in the current era of cost containment, recommendations for routine pathological examination of excised pediatric hernia sacs should be reevaluated.  相似文献   
82.
裸眼取换套管工艺是随着油水井老井及腐蚀损坏而开展的一项新的工艺技术。钻井二公司运用该项技术成功地取换修复了因套管腐蚀老化而停产的5口油水井。在取换套管施工过程中,对工具的配套准备、套管割铣工艺及套管回接技术等进行了应用研究,取得了良好的效果。5口井经试压达到了甲方设计要求的,均已恢复了注水及采油生产。  相似文献   
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AIM: To investigate thrombin (500 U.L-1)-, ADP (0.1-30 mumol.L-1)-, and 5-hydroxytryptamine (5-HT, 3 mumol.L-1)-induced aggregation, secretion of ATP and cytosolic-free calcium mobilization in density subpopulations of human washed platelets. METHODS: Using Percoll discontinuous gradient. RESULTS: The human platelets were separated into high density (HD), intermediate density (ID), and low density (LD) subpopulations, and their sizes were diminished with decreasing density (r = 0.978, P < 0.01). The magnitude of aggregations by thrombin, ADP, and 5-HT was more significant in HD platelets than that in LD platelets (P < 0.01). The amount of secretion of ATP induced by thrombin and ADP in HD platelets was also much higher than that in LD platelets (P < 0.01), except for 5-HT which did not cause the ensuring release reaction in any subpopulation of human platelets. Thrombin (1500 U.L-1)-, ADP (mumol.L-1)-, and 5-HT (3 mumol.L-1)-induced cytosolic-free calcium mobilization was evaluated as well. Results showed that the resting level of cytosolic-free calcium concentration ([Ca2+]i) was the same in all subpopulations, about 80-90 nmol.L-1. However, the level of [Ca2+]i mobilization was entirely different, heightened with increasing density. CONCLUSION: The function of HD platelets was much stronger and more active than that of LD platelets in human.  相似文献   
85.
Idiopathic epidural spinal lipomas are rare: only 13 cases have been described in the literature. We report a further case in an obese patient without known etiological factors. Diagnosis of epidural lipomatosis was performed by MRI. Weight reduction was obtained by conservative treatment, reserving surgery in case symptoms did not disappear. Of the 8 obese patients with idiopathic epidural spinal lipomatosis described in the literature, 3 were treated conservatively, with complete regression of symptoms in 2 cases, partial in the other one. In our patient, the radicular symptomatology disappeared once he had lost weight.  相似文献   
86.
PURPOSE: To determine the radiographic, clinical, surgical, and histologic findings in children with cystic fibrosis who develop strictures of the colon. MATERIALS AND METHODS: Ten children (five boys, five girls; age range, 2.5-9.0 years; mean age, 5.5 years), who were treated at the practices of the authors, were retrospectively identified and their medical records reviewed. RESULTS: Radiographic manifestations of the colonic disease included mucosal irregularity and spiculation with nodular thickening of the colonic wall and loss of normal colonic haustration. Luminal narrowing involved long segments of the colon. Longitudinal shortening of the colon was also a prominent feature. The decrease in caliber of the bowel ranged from mild narrowing to complete occlusion of the lumen. Histologic examination revealed severe submucosal fibrosis and fatty infiltration with transmural extension of the fibrosis to involve the serosa in some cases. Unlike in Crohn disease, however, acute inflammatory changes were minimal or absent. CONCLUSION: Colonic stricture in children with cystic fibrosis is due to irreversible and frequently progressive narrowing of the colonic lumen.  相似文献   
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An integral equation approach was recommended for modelling and simulation of heat and mass transfer processes. It was shown that several mixing models that have been dealt with up to now dlfferently, can be unified in a single integral equation. An effective numerical method was developed for the solution of non-linear integral equation. A construction method for the source and kernel functions were lntroduced in connection with the simulation and control of heat treatlng processes taking place in tunnel kiln and heat and mass transfer processes in tunnel dryer.

We have concluded that our method is advantageous If the slmulated process 1s slgnlficantly affected by the degree of mixing and/or the kernel function can be determined by direct measurement of the streaming phases including feedback, recirculation etc.  相似文献   
90.
Genistein, found in soy products, is a phytochemical with several biological activities. In the current study, our research focused on the estrogenic and proliferation-inducing activity of genistein. We have demonstrated that genistein enhanced the proliferation of estrogen-dependent human breast cancer (MCF-7) cells in vitro at concentrations as low as 10 nM, with a concentration of 100 nM achieving proliferative effects similar to those of 1 nM estradiol. Expression of the estrogen-responsive gene pS2 was also induced in MCF-7 cells in response to treatment with a concentration of genistein as low as 1 microM. At higher concentrations (above 20 microM), genistein inhibits MCF-7 cell growth. In vivo, we have shown that dietary treatment with genistein (750 ppm) for 5 days enhanced mammary gland growth in 28-day-old ovariectomized athymic mice, indicating that genistein acts as an estrogen in normal mammary tissue. To evaluate whether the estrogenic effects observed in vitro with MCF-7 cells could be reproduced in vivo, MCF-7 cells were implanted s.c. in ovariectomized athymic mice, and the growth of the estrogen-dependent tumors was measured weekly. Negative control animals received the American Institute of Nutrition (AIN)-93G diet, the positive control group received a new s.c. estradiol (2 mg) pellet plus the AIN-93G diet, and the third group received genistein at 750 ppm in the AIN-93G diet. Tumors were larger in the genistein (750 ppm)-treated group than they were in the negative control group, demonstrating that dietary genistein was able to enhance the growth of MCF-7 cell tumors in vivo. Increased uterine weights were also observed in the genistein-treated groups. In summary, genistein can act as an estrogen agonist in vivo and in vitro, resulting in the proliferation of cultured human breast cancer cells (MCF-7) and the induction of pS2 gene expression. Here we present new information that dietary genistein stimulates mammary gland growth and enhances the growth of MCF-7 cell tumors in ovariectomized athymic mice.  相似文献   
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