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111.
We describe a new pyeloureteral drainage catheter that can be used for both genitourinary tract stenting and drainage, as well as tamponade of bleeding from the renal parenchyma or subcutaneous tissue. Primary indications for the use of this catheter and recommendations on insertion techniques are presented. With the exception of one case of minor kinking of the catheter, we have had no complications or failures with this catheter. While insertion through an unprotected tissue track is somewhat difficult, we have had good success introducing the catheter through a 24-F or larger Teflon working sheath. The catheter has excellent patient retention properties. It can be converted from external to internal drainage or vice versa simply and quickly on the ward.  相似文献   
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Background

Enteral feeding of very low birth weight (VLBW) infants is a challenge, since metabolic demands are high and administration of enteral nutrition is limited by immaturity of the gastrointestinal tract. The amino acid glutamine plays an important role in maintaining functional integrity of the gut. In addition, glutamine is utilised at a high rate by cells of the immune system. In critically ill patients, glutamine is considered a conditionally essential amino acid. VLBW infants may be especially susceptible to glutamine depletion as nutritional supply of glutamine is limited in the first weeks after birth. Glutamine depletion has negative effects on functional integrity of the gut and leads to immunosuppression. This double-blind randomised controlled trial is designed to investigate the effect of glutamine-enriched enteral nutrition on feeding tolerance, infectious morbidity and short-term outcome in VLBW infants. Furthermore, an attempt is made to elucidate the role of glutamine in postnatal adaptation of the gut and modulation of the immune response.

Methods

VLBW infants (gestational age <32 weeks and/or birth weight <1500 g) are randomly allocated to receive enteral glutamine supplementation (0.3 g/kg/day) or isonitrogenous placebo supplementation between day 3 and 30 of life. Primary outcome is time to full enteral feeding (defined as a feeding volume ≥ 120 mL/kg/day). Furthermore, incidence of serious infections and short-term outcome are evaluated. The effect of glutamine on postnatal adaptation of the gut is investigated by measuring intestinal permeability and determining faecal microflora. The role of glutamine in modulation of the immune response is investigated by determining plasma Th1/Th2 cytokine concentrations following in vitro whole blood stimulation.
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A major drawback of currently used exchange guide wires is insufficient stiffness, causing them to buckle or dislodge when used during catheter exchanges. A new heavy-duty exchange guide wire is described that facilitates catheter exchanges around sharp corners, such as those encountered during various cardiac interventional procedures. The wire was successfully used in experimental valvuloplasty and experimental dilation of the ductus arteriosus.  相似文献   
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Obstruction of urine flow and urine leaks are potentially life-threatening complications in renal transplant patients. The diagnosis is difficult, and definite treatment may therefore be delayed. This paper reviews the clinical course of ten renal transplant patients with urologic complications, discusses the limitations of the standard tests used to investigate such problems, and describes the role of percutaneous antegrade pyelography and nephrostomy drainage catheter placement as safe and accurate diagnostic and therapeutic procedures.  相似文献   
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To gain more understanding about the changes that follow balloon angioplasty, an electron and light microscopic study was carried out in normal canine arteries. Thirty-five arterial segments were dilated with balloon catheters. Early changes consisted of denudation of the intima with widespread necrosis of myocytes and dehiscence of collagen fibers. After three days, myocytes had disappeared leaving empty spaces and edematous ground substance. After two weeks, reendothelization occurred and there was evidence of intimal hyperplasia persisting up to two months. Repair of the dilated arterial segments occurred by proliferation of myocytes, formation of intima, and proliferation of collagen. In two to three months, repair of the intima and media was completed. After six months, dilated segments were characterized by persistent intimal hyperplasia and increased collagen content in the media.  相似文献   
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