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61.
62.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
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64.
It has been suggested that proliferation of enterobacteriaceae and/or anaerobes in the duodenum of some children with acute diarrhoea determines whether the episode becomes persistent. A review of published studies and the comparison of cultures of duodenal aspirates from Peruvian children with acute and persistent diarrhoea and diarrhoea-free children did not support this hypothesis. Although many children had enterobacteriaceae and/or anaerobes cultured there was no correlation with clinical and nutritional outcome. Age, nutritional status, the environment and the aetiology of the episode were determinants of the duodenal microflora independent of diarrhoea. Culture of the duodenal aspirates did not increase the yield of enteropathogens which were isolated more frequently from stools than from the duodenum. Despite the presence of a single strain or serotype of enterobacteriaceae suggesting that these bacteria were colonizing the duodenum, we were unable to demonstrate any adherence mechanisms in the majority of them. Two often bacteria with no other evidence of virulence caused diarrhoea in the RITARD rabbit model.  相似文献   
65.
It is important that a routine search be done roentgenographically for intramural intestinal gas. Several different patterns may be present, but unfortunately, classification of the findings is not helpful in predicting either the cause, or the presence, of gangrene. Also, the clinical circumstances in which intramural intestinal gas is discovered are important--if seen in a patient with acute pain in the abdomen, panmural gangrene is nearly always present and early operation desirable. However, if first discovered in the early postoperative period, a more selective approach is possible. Although many of the patients with intramural intestinal gas died, approximately one-quarter will survive. Hopefully, more timely recognition of intramural intestinal gas will allow earlier surgical intervention in some patients with ischemia of the intestine.  相似文献   
66.
BACKGROUND: Minimally invasive surgical techniques have become routinely applied to the evaluation and treatment of patients with isolated diaphragmatic injuries due to penetrating trauma. The objective of the study was to compare the healing of diaphragm injuries as determined by macroscopic inspection, histologic appearance, and tensile strength following repair by open suturing, laparoscopic suturing, and laparoscopic stapling techniques in an animal model. METHODS: Using a pig model, three injuries were created and repaired in each hemidiaphragm of five animals, for a total of 30 lacerations. These injuries were repaired using single-layer open repair, single-layer laparoscopic repair, or laparoscopic stapling. After a 6-week healing period the animals were sacrificed. The gross integrity, histologic appearance using H+E and trichrome satins, and tensile strength of each repair were assessed. RESULTS: All injuries were grossly intact without dehiscence or herniation. Histologic examination revealed no difference in the collagen deposition between the three groups. The tensile strengths of each type of repair were similar. CONCLUSION: Laparoscopic techniques used to repair diaphragmatic injuries allow for adequate healing equivalent to open sutured repairs. Simple approximation of the peritoneum with laparoscopic staples allows full-thickness healing of these injuries.  相似文献   
67.
Very-low-birthweight (VLBW) neonates are more prone to complications and death than term infants are. In a 15-year period, 19 neonates with VLBW were operated on for necrotizing enterocolitis (NEC). Indications for operation were pneumoperitoneum in 12 and deterioration of general condition in 7. Bowel resection and intestinal diversion was performed in 12, a lateral enterostomy at the site of perforation was created in 5, and 2 neonates with necrosis of the whole bowel underwent an exploratory laparotomy without any further surgical treatment. Surgical complications were found in one-third of the patients. The mortality rate was significantly higher when the ileum was affected. The survival rate was 68%. Prior to 1984 the survival rate was 37% (3/8); subsequently, it has improved to 91% (10/11) as a result of improved intensive therapy.  相似文献   
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The injection of a γ-emitting tracer in backward-facing step flow was modelled. Flow and concentration fields were calculated by CFD and detector responses by a Monte-Carlo code. The objective was to show the influence of the radiotracer energy on the detector response, so as to interpret better data from radiotracer experiments. The radiotracer selection is important in obtaining reliable results, each specific case requiring careful analysis of the experimental data. However, more work is still required to achieve the prescribed goal aimed at.  相似文献   
70.
We sampled, using the brain dialysis technique, interstitial fluid adenosine from the frontal cortex of newborn piglets subjected to hemorrhagic hypotension while measuring sagittal sinus blood flow, cerebrovascular resistance (CVR), and cerebral O2 delivery. In group 1 (n = 8), MABP was reduced in successive steps from 76 to 30 mm Hg with decrements of approximately 10 mm Hg. At 60 mm Hg, CVR decreased by 19% (p less than 0.001), but sagittal sinus blood flow and interstitial fluid adenosine remained unchanged. At 50 mm Hg, both sagittal sinus blood flow and CVR decreased by 19% (p less than 0.001) and interstitial fluid adenosine rose 4.7-fold (p less than 0.05). At 40 and 30 mm Hg, sagittal sinus blood flow decreased further but CVR remained steady, whereas interstitial fluid adenosine rose 10- and 16-fold, respectively. In group 2 (n = 7), an abrupt reduction of MABP from 80 to 47 mm Hg produced no change in sagittal sinus blood flow and a 29% decrease in CVR (p less than 0.01). Interstitial fluid adenosine increased twofold (p less than 0.01). In group 3 (n = 7), an abrupt reduction of MABP from 79 to 40 mm Hg decreased sagittal sinus blood flow and CVR by 24 and 30%, respectively (p less than 0.01). Interstitial fluid adenosine rose threefold (p less than 0.01). In groups 1, 2, and 3, the increases in interstitial fluid adenosine accompanied decreases in cerebral O2 delivery. In group 4 (n = 7), artificial CSF with a PO2 of 152 mm Hg was perfused through the brain dialysis cannula during graded hypotension.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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