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91.
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Despite its nephrotoxic potential, the aminoglycoside antibiotic gentamicin (GM) is still considered to be an important agent against life-threatening infections. The goal of reducing or protecting against its nephrotoxicity has attracted much effort and attention during the last decade. This article reviews some of the literature published during the last decade on the effects of agents that ameliorate or augment GM nephrotoxicity. Notable among the ameliorating agents are antioxidant agents. These include different classes of compounds that include beta blockers (e.g. carvedilol), superoxide dismutase mimetic agents (e.g. M40403), hormones (e.g. melatonin), iron chelators (e.g. deferrioxamine), vitamins (vitamin C and E) and medicinal plants (e.g. garlic). Other ameliorating agents include antibiotics (e.g. ceftriaxone), antiplatelet drugs (e.g. trapidil) and Ca++ agents that may augment GM nephrotoxicity include cyclosporin and the Ca++-channel blocker verapamil.  相似文献   
93.
Dates are commonly consumed, especially in the Middle East, but their effect on gastrointestinal transit (GIT) has not been quantified. The effect of water and ethanol extracts from date flesh and date pits on the GIT in mice was studied. Fasted unanaesthetized male mice received by gavage either the vehicle (0.02 m/kg), or the extracts at doses of 0.01, 0.02 or 0.04 ml/kg. Two separate groups received either clonidine (1 mg/kg) or yohimbine (2 mg/kg). Two hours later, all animals were given a test meal containing charcoal and gum arabic in water. Thirty min thereafter, they were killed and the distance the charcoal column had traveled along the small intestine was measured. Compared with the control, the animals that received the ethanol and water extracts of both date flesh and pits emptied, in a dose-dependent manner, more of their gastrointestinal content. The increase in the GIT ranged from 4 to 22%. However, water extract from dialyzed date flesh induced a dose-dependent decrease in GIT that ranged from 4 to 24%. Clonidine exerted a significant decrease (68%), and yohimbine a significant increase (30%) in the GIT. Depending on the method of extraction, the date extracts may exert an increase or a decrease in GIT.  相似文献   
94.
Purpose. The purpose of this study was to characterise the water mobility in the gel layer of hydrating HPMC tablets. Water mobility in the gel layer of different HPMCs was studied. Methods. NMR imaging, a non-invasive technique, has been used to measure the spatial distribution of self-diffusion coefficient (SDC) and T2 relaxation times across the gel layer. Results. It has been shown that there is a water mobility gradient across the gel layer of HPMC tablets. Although SDC and T2 relaxation times in the outer parts of the gel layer approached that of free water, in the inner parts they decreased progressively. Water mobility and SDC in the gel layer of different HPMCs appeared to vary with degree of substitution of the polymer and the lowest values were obtained across the gel layer of K4M tablets. Conclusions. Water mobility varies across the gel layer of hydrating HPMC tablets and it is dependent on the degree of substitution of the polymer.  相似文献   
95.
Flow-directed pulmonary artery catheters provide important information regarding intravascular volume status, cardiac function and vascular resistance. We describe an unusual complication of pulmonary artery catheterization in which a knot formed at the distal end was torn away from the catheter body and migrated from its original position in the right subclavian vein to a distal branch of the right pulmonary artery. Careful attention to insertion and withdrawal techniques could prevent this potentially serious complication.  相似文献   
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Ten patients with complex non-union of the tibia were treated by locked intramedullary nailing. These patients had scarred skin as a result of initial severe open fractures, multiple debridement or fasciotomies with external fixators and skin grafts applied. Seven of the patients also had previous osteomyelitis or pin track infections. Fully pain-free walking was achieved in all patients and radiological union in nine patients without the need for a bone graft. Four patients developed infection after nailing, of which three resolved with treatment.  相似文献   
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Abdominal Stab Wounds in Children: an 18-Year Experience   总被引:1,自引:0,他引:1  
Objective: Evaluation of the diagnosis, management, and the role of selective treatment in children with abdominal stab wounds. Patients and Methods: 59 children (56 male and three female) were included in the study. The patients' median age was 11.8 years (range, 5–14 years). Time between injury and admission was about 3 h. Laparotomy was performed in 44 patients (74%). Solid organ injury was detected in 32 of these patients (73%) and could not be observed in twelve (27%). 15 patients (26%) were treated conservatively, and only one (6.6%) underwent laparotomy during the follow-up. The stomach was the most frequently injured organ (ten patients), followed by the intestines (nine patients). Types of surgical treatment were as follows: primary suture in 28 patients, resection-anastomosis in three, and osteotomy in two. Results: Some prognostic factors such as presence of abdominal organ evisceration and pneumoperitoneum were not significantly correlated with intraabdominal organ injury, whereas some other risk factors such as acute abdomen on admission (p < 0.002) or abdominal clinical and hemodynamic findings (p < 0.001) showed significant correlation with intraabdominal organ injury. The relative risk (odds ratio) of developing an intraabdominal organ injury was > 2 for patients with signs of an acute abdomen on admission. Postoperative complications were observed in five patients with organ injuries. None of our patients died. Conclusions: Conservative treatment can be safely performed in most children with abdominal stab injuries. Signs of major internal hemorrhage or generalized peritonitis are an absolute indication for emergency operation for abdominal stab wounds. Peritoneal penetrations, free air on the abdominal X-ray, and omental or intestinal evisceration are poor indicators of significant organ injuries, and patients presenting these signs shold be closely followed up for developing acute abdominal symptoms. Received: November 2, 2001; revision accepted: February 15, 2002  相似文献   
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