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Studies were conducted to evaluate the effect of experimental protocol on the ability of benzidine (BZD), dimethylbenzanthracene (DMBA) and mitomycin C (MMC), administered by intraperitoneal injection, to induce micronuclei in polychromatic erythrocytes (PCE) of B6C3F1 mice. Three different treatment/sampling protocols were used, involving from one to three consecutive daily treatments and from three to one, respectively, consecutive daily samplings beginning 24 h after the last injection. DMBA and MMC elicited a significant micronucleus response in all three experimental protocols, while BZD induced a significant response only in the multiple injection protocols. Of the three protocols, the 3-day injection/single sample time protocol offers the greatest efficiency in minimizing the number of animals required in a study, in decreasing the time needed for scoring and in simplifying the statistical analysis. In addition, a comparison of the frequency of micronucleated PCE in peripheral blood and bone marrow following the treatment of mice with either BZD or DMBA suggests that, following a three injection protocol, either tissue can be used with equal efficacy.  相似文献   
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The term 'blood substitute' is commonly used to describe products which can carry and deliver oxygen. These products are also referred to as 'oxygen carriers' or 'oxygen therapeutics'. Blood substitutes are a new generation of oxygen therapeutics and their introduction will redefine treatment approaches in a wide range of medical and surgical practices. There are two major classes of this new generation of oxygen therapeutics (1) modified haemoglobin solutions, referred to as haemoglobin-based blood substitutes (HBBS) and (2) perfluorocarbon emulsions. Tremendous progress has been made in the past four years with the development of HBBS. In comparison, not much progress has been made in the development of perfluorocarbons as oxygen carriers. In the present review we have limited our discussion to the development of HBBS. Several types of HBBS have been developed and are in different phases of clinical trials. Free haemoglobin has been crosslinked, conjugated, polymerised or encapsulated to prevent its dissociation into dimers. The stability and purity of HBBS are extremely important in overcoming most of the significant toxicities of these products. Commercial manufacturers have utilised better proprietary formulations and purification technologies, and HBBS developed by these organisations have demonstrated safety in both preclinical and clinical studies. Recent research activities suggest a broad range of therapeutic applications for these new generation of oxygen therapeutics, 'blood substitutes'. The introduction of HBBS in critical care medicine will introduce a new approach of not only improving perfusion, but delivering oxygen to tissues.  相似文献   
15.
Out of 50 children (100 ears) undergoing adeno-tonsillectomy, 34 ears had hearing threshold 20–50 dB (20dB is normal) and 32 ears showed negative middle ear pressure of 100 to 400 mmH2O (100 mmH2O is normal). Post-operatively only 7 ears had hearing threshold of 20–30 dB and negative middle ear pressure of 100 to 200 mmH2O. Thus adenoidectomy improves eustachian tube functions.  相似文献   
16.
Acinetobacter baumannii is emerging as a major cause of nosocomial infections particularly in high risk patients. Being resistant to adverse environmental conditions, it can stay for prolonged periods in the hospital environment. We report an outbreak in the medical oncology ward where nine patients suspected of bacteraemia were blood culture positive forA. baumannii from the two samples each, one collected through the i.v. cannula and another through the peripheral venous puncture. The bacteria was also isolated from the environmental sources from the various samples collected. The biotype, antibiogram, cellular protein profiles on SDS-PAGE and the restriction enzyme analysis patterns of the patient isolates and the environmental isolates were similar. This points to the environment as a source of infection. With reinforcement of proper barrier nursing and use of disposable heparine ampoules it was possible to control the outbreak.  相似文献   
17.
Here 15 cases of advanced Juvenile angiofibroma are presented. Advantages of wide tumour exposure and preoperative embolization are discussed.  相似文献   
18.
Here we present 10 cases of rhinocerebral aspergillosis. In this study we included only invasive type of cases. In 4 of these disease had extended into the brain parenchyma and in remaining cases diseases had extended intracranially but dura was not invaded. Details about the operative procedure and followup is presented. Till date only 3 of these cases are surviving.  相似文献   
19.
Mutations of the p53 tumor suppressor gene have been used as molecular genetic markers of disease and serve as a prognostic indicator in various malignancies including non-Hodgkin's lymphoma (NHL). Alterations in the p53 gene were investigated in a bone marrow sample from a NHL patient admitted for autologous bone marrow transplantation. Diffuse mixed small and large cell NHL, was initially diagnosed which eventually progressed to large cell lymphoma at relapse following poly-chemotherapy. A sequential technique of polymerase chain reaction-mediated single-strand conformational polymorphism (PCR-SSCP) of the p53 gene revealed a shift in one band of exon 6 in the bone marrow, collected at the time of initial diagnosis. No mutations were detected in exons 5, 7, 8 and 9. Direct sequencing of exon 6 detected a single base change from G to C resulting in an amino acid substitution from glycine to histidine. Results of this study and data reviewed from other publications suggest that the missense p53 mutation seen in this patient at the time of diagnosis may perhaps have been used to predict the eventual outcome of the disease. This could, therefore, serve as an important genetic disease marker particularly in bone marrow or peripheral blood samples initially collected and cryopreserved for future possible autologous transplantation.  相似文献   
20.
Bilateral congenital eventration of the diaphragm almost uniformly presents in infancy with respiratory compromise and is associated with a high mortality rate. Delayed presentation of diaphragmatic eventration in older children and adults may be associated with acute gastric volvulus. Thus, any patient with abdominal pain, vomiting, or nonspecific gastrointestinal symptoms in association with abnormal diaphragmatic findings on chest x-ray should undergo further diagnostic workup with upper gastrointestinal series or computed tomography (CT) scan. Treatment of gastric volvulus requires immediate surgical repair to prevent subsequent necrosis and perforation. The authors describe a case report of bilateral congenital diaphragmatic eventration complicated by a perforated gastric volvulus in a 13-year-old boy. Emergent reduction of the volvulus, closure of the perforated stomach, plication of the diaphragm, and placement of gastrostomy was performed successfully.  相似文献   
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