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41.
AIM: To study the effect of nimodipine (Nim) on infectious brain edema (BE). METHODS: An infectious BE model was induced by injection of Bordetella pertussis suspension (BPS) into right internal carotid artery in rabbits. Eighteen rabbits were randomly divided into 3 groups (n = 6). Group BE: BPS (0.6 mL.kg-1) was given; group NS: normal saline was given as control; group Nim: 10 min after injection of BPS, Nim, 10 micrograms.kg-1, was injected i.v. as a bolus followed by continuous infusion of 0.75 microgram.kg-1.min-1. All the rabbits were kept under observation for 4 h. Evans blue staining was assessed; water, calcium, calmodulin (Cal), and sodium contents were determined in the right brain. RESULTS: Nim vs BE: water 82.2 +/- 1.0% vs 84.4 +/- 1.2 (P < 0.01); calcium 10.5 +/- 1.3 mmol.kg-1 dry tissue vs 17.5 +/- 1.4 (P < 0.01); Cal 15.9 +/- 1.8 mumol.kg-1 wet tissue vs 24.0 +/- 3.0 (P < 0.01); sodium 173 +/- 7 mmol.kg-1 dry tissue vs 275 +/- 38 (P < 0.05). No significant difference for Evans blue staining between the two groups. CONCLUSION: Nim had beneficial effect on the infectious BE. 相似文献
42.
The Cancer Committee of the College of American Pathologists has prepared an update of the consensus statement on premalignant breast lesions and breast cancer risk that was originally published in the Archives of Pathology & Laboratory Medicine in 1986. The objective of this publication is to better define the relative breast cancer risk associated with specific histologic abnormalities by incorporating data derived from recent case-control studies. Explanatory notes are used to document and explain specific risk classifications. In addition to refining the degree of risk associated with individual lesions, such as fibroadenoma and atypical hyperplasia, this update includes a discussion of age-specific breast cancer risk and provides examples that can be used when counseling patients. 相似文献
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Although rare, drug abuse problems present a complex set of physical and psychosocial issues that complicate cancer treatment and pain/ symptom management. Most oncologists are not be well versed in either the conceptual or practical issues related to addiction. As a result, they often struggle in their attempts to effectively treat patients who are or have been substance abusers, and they find it difficult to understand issues of addiction in patients with pain who have no history of substance abuse. In the first installment of a two-part series, the authors explore the epidemiology of substance abuse. An examination of the distinctions between abuse and dependence leads to definitions of these terms appropriate for the oncology setting. Guidelines for assessing aberrant drug-taking behavior are also offered. Part 2, which will appear in the next issue of ONCOLOGY, will discuss the clinical management of cancer patients with a history of substance abuse. 相似文献
46.
M Nishikawa P Chowdhury K Takaori GT Blevins PL Rayford 《Canadian Metallurgical Quarterly》1998,9(2):26-30
Excitability of functionally different alpha-motoneurons was studied in 62 patients with gunshot injuries of nervous trunks of lower extremities both before and during process of rehabilitation by means of physical factors. The correlation of reactions of spinal cord motoneurons and the degree of injuries of nervous trunks was observed. Neuroapraxia of nervous trunks was accompanied by multidirectional alterations in reflex activity of large and small alpha-motoneurons. It was depressed in axonothermesis and lost in simultaneous full anatomic interruption of ischiatic nerve and trunks of both fibular and tibial nerves. Under influence of physical factors the function of motoneurons was normalized in neuroapraxia and was improved in axonothermesis of nervous trunks. 相似文献
47.
H Park YM Go PL St John MC Maland MP Lisanti DR Abrahamson H Jo 《Canadian Metallurgical Quarterly》1998,273(48):32304-32311
Shear stress, the dragging force generated by fluid flow, differentially activates extracellular signal-regulated kinase (ERK) and c-Jun NH2-terminal kinase (JNK) in bovine aortic endothelial cells (BAEC) (Jo, H., Sipos, K., Go, Y. M., Law, R., Rong, J., and McDonald, J. M. (1997) J. Biol. Chem. 272, 1395-1401). Here, we examine whether cholesterol-enriched compartments in the plasma membrane are responsible for such differential regulation. Pretreatment of BAEC with a cholesterol-binding antibiotic, filipin, did not inhibit shear-dependent activation of JNK. In contrast, filipin and other membrane-permeable cholesterol-binding agents (digitonin and nystatin), but not the lipid-binding agent xylazine, inhibited shear-dependent activation of ERK. The effect of cholesterol-binding drugs did not appear to be due to membrane permeabilization, since treatment of BAEC with a detergent, Triton X-100 which also permeabilizes membranes, did not inhibit shear-dependent activation of ERK. Furthermore, shear-dependent activation of ERK, but not JNK, was inhibited by cyclodextrin, a membrane-impermeable cholesterol-binding agent, which removes cell-surface cholesterol. Moreover, the effects of cyclodextrin were prevented by adding cholesterol during the incubation. These results indicate that cholesterol or cholesterol-sensitive compartments in the plasma membrane play a selective and essential role in activation of ERK, but not JNK, by shear stress. Although exposure to shear stress (1 h) increased the number of caveolae by 3-fold, treatment with filipin had no effect in either control or shear-exposed cells suggesting that caveolae density per se is not a crucial determinant in shear-dependent ERK activation. In summary, the current study suggests that cholesterol-sensitive microdomains in the plasma membrane, such as caveolae-like domains, play a critical role in differential activation of ERK and JNK by shear stress. 相似文献
48.
The effect of Pseudomonas aeruginosa infection on clinical parameters in steady-state bronchiectasis
PL Ho KN Chan MS Ip WK Lam CS Ho KY Yuen KW Tsang 《Canadian Metallurgical Quarterly》1998,114(6):1594-1598
STUDY OBJECTIVE: To investigate the effect of Pseudomonas aeruginosa infection on clinical parameters in Chinese patients with noncystic fibrosis and steady-state bronchiectasis. DESIGN: Prospective, cross-sectional clinicomicrobiological study with informed consent. SETTING: Consecutive outpatient recruitment from a specialist bronchiectasis respiratory clinic. PATIENTS: Outpatients (n = 100; 62 women; 55.1+/-16.7 years old; FEV1/FVC 1.4+/-0.7/2.1+/-0.9 L), who had stable respiratory symptoms for more than 3 weeks. MEASUREMENTS AND RESULTS: Respiratory pathogens isolated from the sputum were: Pseudomonas aeruginosa (33), Haemophilus influenzae (10), Moraxella catarrhalis (2), other Gram-negative bacilli (5), Streptococcus pneumoniae (6), Staphylococcus aureus (5), mycobacteria (3), and yeast (1). Clinical parameters in patients with positive isolation of P aeruginosa were compared with those without the organism in the sputum culture (non-P aeruginosa). In the P aeruginosa group, the FEV1/FVC ratio and sputum volume were lower (p < 0.005) and higher (p < 0.0001), respectively, than those of the non-P aeruginosa group. The FEV1/FVC ratio (< 60%) and sputum volume (grading > 5) were independently associated with a positive sputum isolation of P aeruginosa with odds ratios of 3.1 (confidence interval [CI] 1.2 to 8.4; p < 0.01) and 4.7 (CI 1.6 to 13.3; p < 0.001), respectively. CONCLUSIONS: P aeruginosa is the predominant respiratory pathogen isolated in the sputum of Chinese patients with steady-state bronchiectasis, and its isolation is associated with high sputum output (> or = 75th quartile) and moderately severe airflow obstruction (FEV1/FVC < 60%). 相似文献
49.
OBJECTIVE: To assess the ability of certain derivatives of beta-cyclodextrin to treat sheep affected by tunicaminyluracil toxicity, using tunicamycin poisoning as a model system. DESIGN: Controlled treatment trial. ANIMALS: One hundred and sixty Merino wethers were used in the studies. PROCEDURE: Groups of sheep were experimentally poisoned with tunicamycin. Derivatives of beta-cyclodextrin, with or without magnesium sulphate and magnesium gluconate, were administered to treatment groups daily for 2 to 3 days. Treatment groups were compared with untreated groups in terms of survival. RESULTS: A significant increase in survival was observed following treatment of tunicamycin-affected sheep with hydroxypropyl-beta-cyclodextrin (HP beta-CD) and magnesium sulphate in solution (P < 0.05). In subsequent trials, formulation of the cyclodextrin in the form of a magnesium gluconate gel suspension demonstrated significant protection (P < 0.01) and was equally as effective as the cyclodextrin in solution, but required half the frequency of administration, even when the treatment was not commenced until 24 h after the final toxin dose. Beta-cyclodextrin-epichlorohydrin copolymer also improved the survival rate. After toxin administration, the sheep lost significantly less weight if treatment with HP beta-CD was commenced early (P < 0.001). CONCLUSION: Protection studies using these two beta-cyclodextrin derivatives suggest that they may be effective in increasing the survival of sheep poisoned by tunicamycin and warrant further testing in field outbreaks of annual ryegrass toxicity. 相似文献
50.
GA Storch RS Buller TC Bailey NA Ettinger T Langlois M Gaudreault-Keener PL Welby 《Canadian Metallurgical Quarterly》1994,32(4):997-1003
This study compared PCR and an assay for cytomegalovirus (CMV) pp65 antigenemia (CMV-vue; INCSTAR Corp.) with a quantitative shell vial culture (QSVC) technique for the detection of CMV in serial blood specimens from 46 solid-organ transplant recipients. In a comparison based on 535 specimens tested by PCR and QSVC, CMV was detected by PCR in 41 and by QSVC in 37 of 43 recipients at risk of CMV infection. The mean number of days after transplantation of initial detection of CMV was 29.9 for PCR and 34.0 for QSVC (P = 0.01). The antigenemia assay was performed on 395 specimens, including 304 of those also tested by PCR. In these specimens, CMV was detected by the antigenemia assay, QSVC, and PCR in 30, 32, and 35 (respectively) of 38 patients at risk, with no statistically significant difference in the time to detection. Each of the assays detected CMV in similar proportions of patients with and without clinically significant CMV infection. PCR stayed positive longer after transplantation than the other assays but frequently returned to negative when more than 6 months had elapsed after transplantation. The antigenemia assay and PCR stayed positive longer after institution of antiviral therapy than QSVC. PCR can provide highly sensitive detection of CMV viremia, but a PCR assay for CMV is not yet available in kit form. The pp65 antigenemia assay and shell vial culture are quantifiable and comparable in sensitivity. Either is recommended for rapid detection of CMV in blood specimens from solid-organ transplant recipients. 相似文献