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BACKGROUND AND METHODS: Major trauma or abdominal injury may lead to the development of increased intra-abdominal pressure (IAP) and the onset of the abdominal compartment syndrome. Although the effect of raised IAP on systemic and splanchnic hemodynamics have been described, the consequences of the resultant gut hypoperfusion in this setting are unknown. Bacterial translocation (BT) occurs after a period of splanchnic ischemia and may contribute to later organ failure. A rodent model was used to examine the effect of raised IAP on ileal mucosal blood flow (MBF) and BT. IAP was increased to 25 mm Hg for 60 minutes and mean arterial blood pressure was maintained with fluid. Animals were killed 24 hours later and examined for BT. RESULTS: Increased IAP resulted in a decrease of MBF to 63% of baseline despite maintaining normal mean arterial blood pressure. BT occurred principally to the mesenteric lymph nodes after 60 minutes of IAP at 25 mm Hg. CONCLUSIONS: Increased IAP leads to decreased MBF and to BT, which may contribute to later septic complications and organ failure.  相似文献   
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Transbronchial needle aspiration (TBNA) is a valuable, minimally invasive procedure for diagnosing and staging lung cancer in patients, but it is underutilized by practicing pulmonologists. To assess the approach to TBNA of current pulmonary Fellows, we recorded their computerized interactive responses during the 1995 American College of Chest Physicians Fellows' Conference. Among 109 Fellows attending, only 10% reported that they routinely (> or = 85% of cases) performed TBNA to diagnose or stage malignant disease, and 40% noted that they rarely (< or = 5% of cases) performed it. They estimated their diagnostic TBNA yields in patients with mediastinal cancer as follows: > or = 80% by 2% of Fellows; between 25% and 80% by 54% of Fellows; and < 25% by 45% of Fellows. They noted that the main limitations of TBNA at their institutions were suboptimal bronchoscopy technique (30%), technician support (1%), cytopathology support (14%), all of these factors (25%), or the belief that TBNA is not useful (30%). TBNA is currently underutilized and/or underemphasized at bronchoscopy training programs. Major modifications of Fellow experiences are necessary if TBNA is to impact optimally on patient management.  相似文献   
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Therapeutical efficacy of laferon (J2-interferon) was in children of preschool and school ages with acute respiratory viral infections. Endonasal employment of the drug during 3 days of acute period of the illness significantly decreases the duration of the period of catarrh and intoxication, being accompanied by positive immunological reactions on the part of T-cellular immunity and immunoglobulin synthesis.  相似文献   
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Pharmacokinetics was studied of kefsole administered by intravenous and endolymphatic routes to patients (n = 23) with acute pancreatitis. The studies made showed that intravenous route for the drug administration makes for a quicker entering of the antibiotic into the peritoneal exudate. Apart from these reasons, endolymphatic antibacterial therapy does not appear to avert the development of complications involving pus-formation/discharging in acute pancreatitis and does not seem to be essential in the complex of therapeutic measures to be applied for treating the above patients.  相似文献   
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The causes of post operative pyrexia in an orthopaedic unit was studied prospectively in 520 patients who underwent surgery. Two hundred patients (38.4%) developed postoperative pyrexia as defined by having recorded high temperatures of over 38 degrees C on two occasions within 24 hours (excluding the first 24 hours post-operatively). The commonest causes of post-operative pyrexia were wound infection in 70 (13.4%), respiratory tract infections in 40 (7.6%) and malaria in 30 (5.7%) patients, while other causes were urinary tract infection in 20 (3.8%), thrombophlebitis in 15 (2.8%) and deep vein thrombosis in 15 (2.8%) of the patients; while ten (1.9%) patients had pyrexia of undetermined cause despite exhaustive clinical and laboratory workup. The other associated conditions in patients who developed pyrexia were diabetes mellitus in 20 (3.8%), HIV seropositivity and malignancy in 30 (5.7%) and six (1.1%) patients, respectively.  相似文献   
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Few studies have been directed toward elucidating the action of calcitonin (CT) and parathyroid hormone (PTH) on growth plate chondrocytes, cells directly involved in longitudinal bone growth and provisional calcification. In this study, primary cultures of avian growth plate chondrocytes that calcify without the supplement of beta-glycerophosphate were used to investigate the effects of synthetic human CT and 1-34 bovine PTH on (1) cell division and growth; (2) the deposition of Ca2+ and inorganic phosphate (Pi); (3) the activity of alkaline phosphatase (AP), an enzyme long associated with the mineralization process; (4) the levels of proteoglycans; and (5) the synthesis of collagens. Added continually to preconfluent cultures from day 6 until harvest, CT (1-30 nM) and PTH (0.1-1.0 nM) increased mineral deposition; the maximal increase was seen between days 18-21 at 10 nM CT (175-260%) and 0.5 nM PTH (approximately 170-280%), both p < 0.001. CT had no significant effect on cellular protein, or AP-specific activity, whereas PTH increased cellular protein, DNA, proteoglycan, and collagen content of the cultures in a dosage-dependent manner. AP activity and levels of Type II and X collagens and fibronectin in the culture medium showed a biphasic response to PTH; maximal increases were seen at 0.5 nM between days 15-18. Longer exposure (days 21-27) to PTH at higher levels (5-10 nM) caused a marked decreased in AP activity but a lesser decrease in the collagens. These results indicate that CT and PTH can act directly on chondrocytes to stimulate mineralization, but that PTH specifically stimulated cell division and synthesis of cellular and extracellular proteins by growth plate chondrocytes. The implications of these findings with regard to Ca2+ homeostasis and bone formation are discussed.  相似文献   
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