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51.
A baby with unilateral cleft lip, midline cleft palate and hypertelorism developed meningitis in the first 48 h of life. Examination of the nasopharynx showed a soft tissue mass, which was confirmed as a basal encephalocele by computed tomography. There was also congenital hydrocephalus and the corpus callosum was absent. Surgical treatment included repair of the anterior basal skull defect, repair of the lip and palate, and ventriculo-peritoneal shunt. There is currently evidence of developmental delay and right-sided visual impairment due to Morning Glory syndrome. This case demonstrates that basal encephalocele should be considered in any baby with midline facial deformity who develops meningitis.  相似文献   
52.
Esthesioneuroblastoma: the University of Virginia experience 1960-1985   总被引:1,自引:0,他引:1  
Twenty-six cases of esthesioneuroblastoma were treated by the Department of Otolaryngology-Head and Neck Surgery from 1960 to 1985. This period was divided into the precraniofacial period (1960 to 1975) and the craniofacial period (1976 to 1985) to denote the transition to a more aggressive combined therapeutic approach. Of the eight patients in the precraniofacial group (group I), only 37.5% are alive without disease. In group II (the craniofacial group), 82% of the patients are alive without disease with an average follow-up of 4 years. This latter survival rate compares favorably with the survival rate of group I and the cure rate of 10% to 67% as stated in other studies.  相似文献   
53.
Moser  GJ; Wolf  DC; Wong  BA; Goldsworthy  TL 《Carcinogenesis》1997,18(5):1075-1083
Unleaded gasoline (UG) vapor (2056 ppm) increased the incidence of liver tumors in a chronic bioassay and exhibited tumor-promoting activity in N-nitrosodiethylamine (DEN)-initiated female mouse liver. Estrogen inhibited mouse liver tumor development and the hepatocarcinogenic and tumor-promoting dose of UG produced uterine changes suggestive of estrogen antagonism. To directly test the hypothesis that UG-induced tumor-promoting ability is secondary to its interaction with the mouse liver tumor inhibitor, estrogen, we compared the tumor-promoting ability of UG in ovariectomized (Ovex) mice with the hepatic tumor-promoting ability of UG in intact mice. Ovaries were surgically removed at 4 weeks of age. Exposure to wholly vaporized UG (2018 ppm) under bioassay and tumor-promoting conditions began at 8 weeks of age. After 4 months of exposure, UG increased relative liver weight and hepatic microsomal cytochrome P450 pentoxyresourfin-O- dealkylase and ethoxyresorufin-O-deethylase activity to a similar extent in intact and Ovex mice. Non-focal hepatocyte proliferation, as measured by the incorporation of bromo-deoxyuridine, was not changed by UG exposure and was similar in all treatment groups. After 4 months of exposure to DEN-initiated mice, UG significantly increased the volume fraction of liver occupied by foci (three-fold) as compared to control intact mice. As expected, volume of foci was elevated in DEN/Ovex/control mice as compared to DEN/intact/control mice. In DEN/Ovex mice UG did not significantly increase the focal volume fraction. Thus, the tumor promoting activity of UG, as demonstrated by increased volume fraction of liver occupied by hepatic foci in intact mice, is greatly attenuated in Ovex mice. The volume fraction data in Ovex mice support the hypothesis that the tumor promoting activity of UG is dependent upon the interaction of UG with ovarian hormones. These data also indicate that hepatic microsomal cytochrome P450 PROD and EROD induction, hepatomegaly and non-focal hepatic LI are not specific markers of hepatic tumor promoting activity of UG.   相似文献   
54.
Transgenic mice with both alleles of the p53 tumor suppressor gene product 'knocked out' by gene targeting are susceptible to early development of tumors, chiefly lymphomas and sarcomas. Compared with the control group, administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male p53-deficient mice extended their lifespan by delaying death due to neoplasms (from 105 to 166 days on study, P = 0.002), primarily by suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P = 0.010). Treatment with a synthetic DHEA analog, 16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet also increased lifespan, to 140 days for mice that developed tumors (P = 0.037). The effects of these steroids on lifespan and tumor development did not appear to be strongly related to inhibition of food consumption and weight gain, in that a group pair-fed with control diet to the reduced food consumption of the DHEA-treated group developed and died of the same types of neoplasms at the same rate as the controls fed ad libitum. The chemopreventive effect of these steroids has been proposed to be due to suppression of DNA synthesis by inhibition of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway. Although DHEA and its analog are strong non- competitive inhibitors of this enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide pools in the liver, as would have been predicted. The chemopreventive effect of DHEA in this model may be due to steroid-induced thymic atrophy and suppression of T cell lymphoma, permitting these mice to survive long enough to develop tumors with longer latency.   相似文献   
55.
Hemolytic uremic syndrome spontaneously arises in a few patients with advanced cancer, but it is more commonly related to the use of certain chemotherapeutic agents. Mitomycin-C is, etiologically, the most common causative agent inducing hemolytic uremic syndrome, in a dose dependent manner. We report this syndrome, attributable to mitomycin-C at a cumulative dose of 40 mg/m2, in a gastric cancer patient. A 42-year-old female with stage III gastric cancer underwent radical gastrectomy and was given mitomycin-C at 10 mg/m2 intravenously every four weeks as adjuvant therapy. Hemolytic uremic syndrome was diagnosed three months after the last dose of mitomycin-C administration. The most prominent symptoms included pallor, hypertension and anasarca, with laboratory evidence of microangiopathic hemolytic anemia, azotemia and hyperkalemia. Her disease was progressive, but fortunately stabilized after staphylococcus column A dialysis. Her disease remained in remission for 24 months from the time of diagnosis, and then relapsed in the form of peritoneal carcinomatosis with partial intestinal obstruction.   相似文献   
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Background

The sudden increase in incidence and magnitude of mine blast injuries prompted us to highlight the problem and its management.

Methods

The cases of mine blast injuries occurring during mining and demining in a particular geographical area were analysed. Total 27 cases of mine blast injuries occurred during mining or demining operations in a period of 13 months.

Results

Various body regions were involved in the mine blast injuries but the main brunt was borne by feet and legs followed by multiple body regions due to splinters. 14 patients underwent below knee (BK) amputation while 4 patients required through knee (TK) amputations. The effect of blast was so severe that most of the cases required 2 to 5 times wound debridements. The initial aggressive debridement / open stump amputation saved the limb and life of all patients.

Conclusion

A mine blast causes extensive injuries and psychological trauma. Management is needed urgently, surgery is difficult, and amputation is often inevitable. Maximum lives and limbs can be saved with aggressive debridement, repeated inspections and dressings under anaesthesia and definitive closure at optimum time.Key Words: Amputation, Antipersonnel mine, Crush syndrome, Debridements, Mine blast injury, Secondary missiles, Shrapenels  相似文献   
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The antagonistic effect of zinc on inhibibition of human aminolevulinic acid dehydratase (ALAD) by lead was examined in vitro. The phenomenon was studied at pH 6.5-7.5 . Zinc and lead were added at concentrations ranging from physiological levels to levels far in excess of those expected in heavy industrial exposure. ALAD activity of normal blood assayed in the presence of zinc was unaffected by exogenous lead if the added zinc concentration was above 0.53 mmol/l blood, or double the normal endogenous level, and was of the order found in heavy industrial exposure to zinc. In this case, ALAD assay values were appreciably raised and might have fallen into the normal range in spite of a dangerous total blood lead of over 0.0048 mmol/l. When zinc was added in vitro to blood from a worker with a blood lead level of 0.0043 mmol/l the ALAD values obtained were also raised and did not reflect the dangerous level of lead in the patient.  相似文献   
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