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141.
SR Sharar NN Chapman LC Flaherty JM Harlan TF Tedder RK Winn 《Canadian Metallurgical Quarterly》1996,157(6):2555-2563
Neutrophil (PMN) recruitment into systemic inflammatory sites in vivo is thought to be initiated by selectin-mediated endothelial adherence. We explored the role of L-selectin (CD62L) in leukocyte emigration following instillation of bacteria into the peritoneum or s.c. skin in rabbits. Pretreatment with blocking mAb against L-selectin (LAM1.3) reduced peritoneal PMN emigration 4 h after i.p. inoculation with 10(10) CFU of Escherichia coli by only 17% compared with animals receiving a nonblocking L-selectin mAb (LAM1.14). Peritoneal PMNs from saline-treated rabbits demonstrated a complete absence of L-selectin, whereas those from LAM1.3-treated animals retained 43% of their baseline L-selectin expression. This suggests that L-selectin shedding is not a requisite event for PMN emigration under these conditions. In rabbits given s.c. inoculations with either Staphylococcus aureus or E coli, pretreatment with mAb LAM1.3 did not significantly impair PMN emigration at 24 h, nor increase the incidence, size, or associated mortality of resulting abscesses at 7 days compared with animals receiving nonblocking mAb LAM1.14. We conclude that: 1) mAb blockade of L-selectin in vivo only modestly affects acute, E. coli-induced peritoneal PMN emigration; and 2) L-selectin blockade does not increase infectious sequelae associated with s.c. bacterial inoculation. These findings of only mildly reduced PMN emigration into the peritoneum and no alteration in s.c. host defense differ from those reported with L-selectin blockade under other, nonbacterial inflammatory conditions, and suggest that redundant selectin-mediated mechanisms (P- and E-selectin) are sufficient for normal PMN emigration in response to bacterial stimulation. 相似文献
142.
SKh al-Shukri NN Petrishchev AG Gorbachev IA Mikha?lova IuA Bobkov IV Kuz''min SIu Borovets IB Savel''eva MV Korokhodkina 《Canadian Metallurgical Quarterly》1997,42(3):38-41
Continuous monitoring of dynamic changes of transcranial regional cerebral oxygenation (rSO2) was performed in 7 healthy volunteers (mean age 40.9 +/- 12.6 years; range 25-62 years) during normo- and hyperbaric oxygenation (HBO at 2.5 and at 1.95 ATA) using an INVOS 3100 cerebral oximeter. A significant change between HBO and control phase could be found in rSO2, alterations (p < 0.05; ANOVA, Tukey test). The results suggest that the calculation of rSO2 may be a useful method to monitor changes of oxygen saturation under hyperbaric conditions. However, the absolute quantification of rSO2 is useless at the moment and needs further investigation. 相似文献
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145.
Diagnostic criteria of T-cell lymphoma and Hodgkin's disease are presented which are the basis of the European-American classification schema (REAL). Brief morphological, immunophenotypical, genetic and clinic characteristics of every tumor type (subtypes variants) are given. The comparison of this REAL section with the Kiel's classification is made with some critical notes concerning, in particular, the Hodgkin's disease classification. 相似文献
146.
Whether there is an endogenous ligand for sigma receptors remains unknown. A total lipid fraction was isolated from the porcine liver, which was then subjected to chromatographic separation, yielding nine chromatographic fractions eluated at various chloroform/methanol ratios: each fraction was tested for its capacity of inhibiting the binding of (+)-[3H]SKF 10047 to hepatic sigma-receptors. The chromatographic fraction 7 + 7A (eluated at chloroform/methanol ratios of 60:40-10:90) which consisted mainly of phospholipids was found to have the highest activity. However, a complex analysis of this fraction revealed no relationship of its sigma-inhibiting activity to phospholipids. It is suggested that the non-competitive inhibition of (+)-[3H]SKF 10047 binding by the isolated active fraction is due to its presence of an endogenous ligand which, interacting with sigma-2 receptor, allosterically inhibits the binding of the labelled (+)-benzomorphan. 相似文献
147.
G Chidlow MS Nash C Crowhurst AJ Bron NN Osborne 《Canadian Metallurgical Quarterly》1996,63(4):463-469
OBJECTIVES: To determine the intraprostatic pathologic changes following accurately measured doses of transurethral microwave thermal energy in patients with benign prostatic hyperplasia. METHODS: Eight patients scheduled for prostate surgery were treated for approximately 1 hour without anesthesia using a newly designed microwave treatment catheter that allows a close impedance match to prostate tissue and concentrates thermal energy preferentially in the anterior and lateral prostate gland. Interstitial, urethral, and rectal temperatures were continuously measured using a novel stereotactic thermal mapping technique. Serial sections of prostate tissue harvested during subsequent surgery were evaluated pathologically with prostate mapping. RESULTS: Microwave treatment resulted in marked and continuous intraprostate temperature elevation, while urethral and rectal temperatures remained low. Peak intraprostate temperatures in individual patients reached as high as 80 degrees C. Mean temperature reached a maximum of 54 degrees C at a radial distance of approximately 0.5 cm from the urethra and remained 45 degrees C or higher up to a distance of 1.6 cm. The predominant pathologic findings were uniform hemorrhagic necrosis and tissue devitalization without significant inflammation. The mean distance from the urethra to the viable-necrotic tissue border was 1.6 +/- 0.2 cm (range, 0.5 to 2.5). At this border, no more than 1 mm in thickness, temperature averaged 45.7 +/- 0.6 degrees C, and there was a suggestion that pure stromal nodules were more resistant to thermal injury. CONCLUSIONS: Microwave treatment can destroy obstructive prostate tissue while maintaining innocuous urethral and rectal temperatures. Temperatures of 45 degrees C or higher for approximately 1 hour cause uniform thermoablation of prostate tissue. 相似文献
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149.
AB Druzhko SK Chamorovsky EP Lukashev AA Kononenko NN Vsevolodov 《Canadian Metallurgical Quarterly》1995,35(2-3):129-132
Photochromic and electrochromic spectral properties of 4-keto-bacteriorhodopsin (4-keto-BR) embedded in a polymer matrix were studied. The light-induced spectral changes were found to be similar to those for 4-keto-BR in suspension, but the duration of the photocycle is substantially longer (up to ten of h). Application of a constant electric field induces a bathochromic shift of the main absorption band, the amplitude of the field-induced spectral changes, showing a quadratic dependence on the field strength. Polymer films containing bacteriorhodopsin analogs show promise as new spectrally-selective photochromic and electrochromic materials. 相似文献
150.