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61.
INTRODUCTION: We retrospectively reviewed the CT findings of the acute abdomen patients examined in the last two years to investigate the frequency of a new CT sign of intestinal infarction, the pneumoretroperitoneum, and its association with other CT findings highly suggestive of this condition. MATERIAL AND METHODS: The CT findings of 60 patients with diagnostic confirmation of intestinal infarction were retrospectively reviewed. CT was performed without (no. = 55) and with (no. = 5) oral administration of contrast material and without (no. = 3) and with (no. = 57) the i.v. injection of nonionic contrast agents in repeated 50 mL boluses. To assess the specificity of this sign, we selected a control group of 400 patients submitted to CT for acute abdomen, but not blunt trauma; 19 of these patients had pneumoretroperitoneum. RESULTS: Pneumoperitoneum was found in five patients with intestinal infarction; it was an isolated sign in two cases and it was associated with few small perihepatic air bubbles in one case. Finally, it was associated with highly suggestive findings of late intestinal infarction in the other two cases. All cases of pneumoretroperitoneum in the control group had been correctly referred to other diseases by previous plain film and/or CT findings and surgery and/or endoscopy confirmed this diagnosis. DISCUSSION AND CONCLUSIONS: Pneumoretroperitoneum has been described as a complication of different benign or severe disorders; prompt recognition of its origin is essential since surgical and/or septic conditions may be involved. However, if the patient's history is negative for abdominal trauma, gastroduodenal ulcer or sepsis, pneumoretroperitoneum is generally cured with conservative treatment. Intestinal infarction or severe ischemia, a usually surgical conditions, should be considered among the different causes of pneumoretroperitoneum alone or associated with pneumoperitoneum or with highly suggestive late findings of infarction such as portal venous gas or pneumatosis intestinalis. This sign had a non-negligible incidence in intestinal infarction in our review (8.5%), but it should be known of and sought with specific window setting to enhance gas depiction on CT images to avoid false negatives. 相似文献
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AE Medvedev T Flo RR Ingalls DT Golenbock G Teti SN Vogel T Espevik 《Canadian Metallurgical Quarterly》1998,160(9):4535-4542
This study was undertaken to evaluate the role of CD14 and complement receptors type 3 (CR3) and 4 (CR4) in mediating TNF release and NF-kappaB activation induced by LPS and cell wall preparations from group B streptococci type III (GBS). LPS and GBS caused TNF secretion from human monocytes in a CD14-dependent manner, and soluble CD14, LPS binding protein, or their combination potentiated both LPS- and GBS-induced activities. Blocking of either CD14 or CD18, the common beta-subunit of CR3 and CR4, decreased GBS-induced TNF release, while LPS-mediated TNF production was inhibited by anti-CD14 mAb only. Chinese hamster ovary cell transfectants (CHO) that express human CD14 (CHO/CD14) responded to both LPS and GBS with NF-kappaB translocation, which was inhibited by anti-CD14 mAb and enhanced by LPS binding protein. While LPS showed fast kinetics of NF-kappaB activation in CHO/CD14 cells, a slower NF-kappaB response was induced by GBS. LPS also activated NF-kappaB in CHO cells transfected with either human CR3 or CR4 cDNA, although responses were delayed and weaker than those of CHO/CD14 cells. In contrast to LPS, GBS failed to induce NF-kappaB in CHO/CR3 or CHO/CR4 cells. Both C3H/OuJ (Lps[n]) and C3H/HeJ (Lps[d]) mouse peritoneal macrophages responded to GBS with TNF production and NF-kappaB translocation, whereas LPS was active only in C3H/OuJ macrophages. Thus, LPS and GBS differentially involve CD14 and CR3 or CR4 for signaling NF-kappaB activation in CHO cells and TNF release in human monocytes, and engage a different set of receptors and/or intracellular signaling pathways in mouse macrophages. 相似文献
64.
Sixty cats which underwent an ovariohysterectomy were randomly allocated into four treatment groups. One group (controls) received no analgesics postoperatively, and the others received either a single dose of buprenorphine (0.006 mg/kg) intramuscularly, or pethidine (5 mg/kg) intramuscularly, or ketoprofen (2 mg/kg) subcutaneously. The analgesia obtained after each treatment was assessed by three measures. There were significant differences between the groups both for the requirement for intervention analgesia (P = 0.0008) and for the overall clinical assessment (P = 0.0003) with ketoprofen requiring least intervention analgesia and having the best overall clinical assessment, followed by buprenorphine then pethidine. The control group required the most intervention analgesia and had the worst overall clinical assessment. Visual analogue scale scoring for pain produced significant differences between the groups from one hour after the operation, with the cats which were given ketoprofen tending to have lower pain scores than the other groups. 相似文献
65.
AE Eggen 《Canadian Metallurgical Quarterly》1993,46(11):1297-1304
In a cross-sectional survey carried out in Troms? in 1986-7, 19,137 men and women aged 12-56 years from the general population were asked about their use of drugs during the preceding 14 days. Use of analgesics was very common. On average 28% of the women and 13% of the men had used analgesics. Drug use due to menstruation discomfort contributed only partly to the gender difference. Drug use was independent of age from 20 years of age. Factors having an impact on analgesic drug use were analyzed by logistic regression. The most significant predictors of analgesic use were suffering from headache (OR = 14.2(women) OR = 24.4(men)) and infections (OR = 2.0(women) OR = 2.4(men)). Drug users also tended to suffer from symptoms of depression (women) and sleeplessness (men). Lifestyle and sociodemographic factors were also significant predictors, but were of marginal importance (OR < 1.5) compared with occurrence of pain and infections. 相似文献
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M Mack B Luckow PJ Nelson J Cihak G Simmons PR Clapham N Signoret M Marsh M Stangassinger F Borlat TN Wells D Schl?ndorff AE Proudfoot 《Canadian Metallurgical Quarterly》1998,187(8):1215-1224
CCR5, a chemokine receptor expressed on T cells and macrophages, is the principal coreceptor for M-tropic HIV-1 strains. Recently, we described an NH2-terminal modification of the CCR5 ligand regulated on activation, normal T cell expressed and secreted (RANTES), aminooxypentane-RANTES (AOP-RANTES), that showed potent inhibition of macrophage infection by HIV-1 under conditions where RANTES was barely effective. To investigate the mechanism of AOP-RANTES inhibition of HIV infectivity we examined the surface expression of CCR5 using a monoclonal anti-CCR5 antibody, MC-1. We demonstrate that AOP-RANTES rapidly caused >90% decrease in cell surface expression of CCR5 on lymphocytes, monocytes/ macrophages, and CCR5 transfected Chinese hamster ovary (CHO) cells. RANTES also caused a loss of cell surface CCR5, although its effect was less than with AOP-RANTES. Significantly, AOP-RANTES inhibited recycling of internalized CCR5 to the cell surface, whereas RANTES did not. When peripheral blood mononuclear cells are cultured for prolonged periods of time in the presence of RANTES, CCR5 expression is comparable to that seen on cells treated with control medium, whereas there is no CCR5 surface expression on cells cultured in the presence of AOP-RANTES. Immunofluorescence indicated that both AOP-RANTES and RANTES induced downmodulation of cell surface CCR5, and that the receptor was redistributed into endocytic organelles containing the transferrin receptor. When RANTES was removed, the internalized receptor was recycled to the cell surface; however, the receptor internalized in the presence of AOP-RANTES was retained in endosomes. Using human osteosarcoma (GHOST) 34/CCR5 cells, the potency of AOP-RANTES and RANTES to inhibit infection by the M-tropic HIV-1 strain, SF 162, correlated with the degree of downregulation of CCR5 induced by the two chemokines. These differences between AOP-RANTES and RANTES in their effect on receptor downregulation and recycling suggest a mechanism for the potent inhibition of HIV infection by AOP-RANTES. Moreover, these results support the notion that receptor internalization and inhibition of receptor recycling present new targets for therapeutic agents to prevent HIV infection. 相似文献
69.
RP Millman CL Rosenberg CC Carlisle NR Kramer DM Kahn AE Bonitati 《Canadian Metallurgical Quarterly》1998,113(4):992-996
Twenty-four patients who failed uvulopalatopharyngoplasty (UPPP) for obstructive sleep apnea (OSA) had an adjustable oral (Herbst) appliance made to treat the persistent apnea. Six patients discontinued the device prior to sleep evaluation. Eighteen patients had polysomnographic evaluations at baseline, post-UPPP, and with the Herbst appliance in place. The apnea-hypopnea index baseline (AHI) and arterial oxygen saturation (SaO2) nadir were 42.3+/-6.1 and 83.6+/-1.8%, respectively. There was no significant change in either parameter with surgery. With the oral appliance, the AHI fell to 15.3+/-4.4 (p < or = 0.01) and the SaO2 nadir increased to 87.9+/-1.2% (p < or = 0.05). Ten of the patients had control of the OSA with the Herbst appliance with a fall in the AHI to < 10. There were, in addition, two partial responders as defined by an AHI of <20 and a >50% fall in AHI compared with baseline and post-UPPP values. All but one of the responders and partial responders had complete resolution of subjective symptoms of daytime sleepiness with the appliance. An adjustable oral appliance appears to be an effective mode of therapy to control OSA after an unsuccessful UPPP. 相似文献
70.