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91.
BACKGROUND: Supraclinoid carotid aneurysms have traditionally been classified according to their relation to the major carotid branches, but considerable variation exists with respect to site of origin, projection, and relationship to the skull base. Distal internal carotid aneurysms with a superior or medial projection are uncommon vascular lesions, with an unusually high incidence of operative complications. METHODS: Surgical experience with five patients suffering from subarachnoid hemorrhage due to ruptured aneurysms of the dorsomedial wall of the distal internal carotid artery is presented, with emphasis on their angiographic appearance, anatomical features, and operative management. RESULTS: All five patients underwent surgical clipping. Intra-operative rupture occurred in two cases, with avulsion of the aneurysm from the internal carotid artery in both. A third patient experienced recurrent subarachnoid hemorrhage three days after uneventful surgery, due to the clip shearing off of the parent vessel. CONCLUSIONS: Distal internal carotid aneurysms do not conform to the usual principles of aneurysm formation and are unique in their dorsomedial location unrelated to an arterial bifurcation. Although their anatomy is straightforward and exposure is not restricted by bone or dural structures of the skull base, they possess extremely fragile necks which make surgical management particularly hazardous. 相似文献
92.
OA Ayangbile JP Fontenot PP Graham DJ Kirk VG Allen 《Canadian Metallurgical Quarterly》1998,76(3):686-693
Exacerbations of asthma have been associated with exposure to ozone or particles with a 50% cut-off aerodynamic diameter of 10 microm (PM10). We postulated in this study that the association of summertime air pollution (i.e. ozone and PM10) with acute respiratory symptoms, medication use and peak expiratory flow differs among patients grouped according to asthma severity. During the summer of 1995, effects of ambient air pollution on these parameters were studied in a panel of 60 nonsmoking patients with intermittent to severe persistent asthma. These patients were recruited from our Pulmonary Out-patient Clinic. Subgroup analysis was performed on the degree of hyperresponsiveness and lung steroid use before the start of the study, as indictors for the severity of asthma. Associations of the parameters studied with ozone, PM10, nitrogen dioxide (NO2), sulphur dioxide (SO2) and black smoke were evaluated using time series analysis. Several episodes with increased summertime air pollution occurred during the 96 day study period. Eight hour average ozone concentrations exceeded the World Health Organization (WHO) Air Quality Guidelines (120 microg x m(-3)) on 16 occasions. Daily mean levels of PM10 were moderately elevated (range 16-98 microg x m(-3)). Levels of the other measured pollutants were low. There was a consistent, positive association of the prevalence of shortness of breath (maximal relative risk (RRmax) 1.18) with ozone, PM10, black smoke and NO2. In addition, bronchodilator use was associated with both ozone and PM10 levels (RRmax 1.16). Stratification by airway hyperresponsiveness and steroid use did not affect the magnitude of the observed associations. No associations with peak expiratory flow measurements were found. We conclude that the severity of asthma is not an indicator for the sensitivity to air pollution. 相似文献
93.
Drug reactions in patients with HIV infection, e.g. fever or rash, are a frequently occurring clinical problem. These side effects particularly are observed with sulfonamides; however, many other drugs have also shown to induce allergic reactions when given to patients with HIV infection. The production of hydroxylamines has been put forward as one of the explanations for these high incidence of reactions on drugs. Since sulfonamides are the first choice of therapy for the treatment and prophylaxis of Pneumocystis carinii pneumonia, several strategies have been developed to circumvent drug reactions. In general rechallenge or desensitization are recommended in literature. This article discusses the results and risks of rechallenge and desensitization with sulfonamides or other drugs, as mentioned in the literature. Furthermore preliminary results of rechallenge with a sulfonamide, which is not metabolized into hydroxylamines, are presented. From the data in the literature it is concluded that desensitization should be preferred to rechallenge. 相似文献
94.
95.
PP Weinstein 《Canadian Metallurgical Quarterly》1998,84(4):730-738
In this prospective, multicenter, double-blind study, the efficacy of ciprofloxacin was compared with that of clarithromycin as therapy for patients with acute bacterial exacerbations of chronic bronchitis (ABECB) from whom a pretherapy pathogen was isolated; the efficacy was measured by the infection-free interval. Clinical and microbiological responses at the end of therapy were secondary efficacy variables. Patients randomly received either ciprofloxacin or clarithromycin (500 mg twice a day for 14 days). Three hundred seventy-six patients with acute exacerbations of chronic bronchitis were enrolled in the study of whom 234 had an ABECB. Clinical resolution was observed in 90% (89 of 99) of ciprofloxacin recipients and 82% (75 of 91) of clarithromycin recipients for whom efficacy could be evaluated. The median infection-free interval was 142 days for ciprofloxacin recipients and 51 days for clarithromycin recipients (P = .15). Bacteriologic eradication rates were 91% (86 of 95) for ciprofloxacin recipients and 77% (67 of 87) for clarithromycin recipients (P = .01). In summary, compared with clarithromycin, treatment of ABECB with ciprofloxacin was associated with a trend toward a longer infection-free interval and a statistically significantly higher bacteriologic eradication rate. 相似文献
96.
ES Hwang B Samli KN Tran PP Rosen PI Borgen KJ Van Zee 《Canadian Metallurgical Quarterly》1998,5(8):757-763
The N-terminal domain (1-318 amino acids) of mouse NFkappaB (p65) has been purified to homogeneity from the soluble fraction of Escherichia coli cells expressing this protein. Its complex with a full-length ikappaB-alpha (MAD3, 1-317 amino acids) molecule was generated by binding the E. coli-derived ikappaB-alpha to the purified NFkappaB and purifying the complex by sequential chromatography. The stoichiometry of NFkappaB to ikappaB in the complex was determined to be 2 to 1 by light scattering and SDS-polyacrylamide gel electrophoresis. The secondary structure of the NFkappaB (p65) determined by Fourier-transform infrared (FTIR) spectroscopy is in good agreement with that of the p50 in the crystal structure of the p50/DNA complex, indicating that no significant structural change in NFkappaB occurs upon binding of DNA. The FTIR spectrum of the NFkappaB/ikappaB complex indicates that its secondary structure is composed of 17% alpha-helix, 39% beta-strand, 18% irregular structures, and 26% beta-turns and loops. By comparing these data to the FTIR data for NFkappaB alone, it is concluded that the ikappaB (MAD3) in the complex contains 35% alpha-helix, 27% beta-strand, 22% irregular structures, and 16% beta-turns and loops. Circular dichroism (CD) analysis of a shorter form of ikappaB (pp40) indicates that it contains at least 20% alpha-helix and that the ikappaB subunit accounts for nearly all of the alpha-helix present in the NFkappaB/ikappaB complex, consistent with the FTIR results. The stabilities of NFkappaB, ikappaB, and their complex against heat-induced denaturation were investigated by following changes in CD signal. The results indicate that the thermal stability of ikappaB is enhanced upon the formation of the NFkappaB/ikappaB complex. 相似文献
97.
E Hanon G Meyer A Vanderplasschen C Dessy-Doizé E Thiry PP Pastoret 《Canadian Metallurgical Quarterly》1998,72(9):7638-7641
Bovine herpesvirus 1 (BHV-1) induces apoptotic cell death in bovine peripheral blood mononuclear cells and B-lymphoma cells. Using a BHV-1 glycoprotein H null mutant, we have demonstrated that although penetration of BHV-1 is not required, attachment of BHV-1 viral particles is essential for the induction of apoptosis. 相似文献
98.
99.
Identification and characterization of an endogenous P2X7 (P2Z) receptor in CHO-K1 cells 总被引:1,自引:0,他引:1
AD Michel IP Chessell AD Hibell J Simon PP Humphrey 《Canadian Metallurgical Quarterly》1998,125(6):1194-1201
100.
M Denis E Hanon FA Rijsewijk MJ Kaashoek JT van Oirschot E Thiry PP Pastoret 《Canadian Metallurgical Quarterly》1996,53(1-2):121-132
Mutant viruses with deletions in genes encoding non-essential glycoproteins are considered as promising bovine herpesvirus 1 (BHV1) vaccine candidates. The present study compared the influence of various gene deletions (gC, gE, gI, gG) on the induction of cell-mediated immune responses against the virus. The highest BHV1 specific lymphoproliferative response was observed in the group of calves inoculated with the gC- mutant. However, in all groups of inoculated calves, limiting dilution analysis showed marked individual variability in the number of BHV1 specific T lymphocytes that were stimulated. The same animals were then challenged with wild-type BHV1. In these animals, limiting dilution analysis did not reveal gE, gI nor gG as a major T lymphocyte antigen. However, further analysis suggested the T cell antigenicity of gE in a low number of BHV1 hyperimmunized calves. Stimulation of MHC unrestricted cytotoxicity was also evaluated after inoculation with the various deletion mutants. Cytotoxicity in gC- inoculated calves was as high as in BHV1 inoculated calves. In conclusion, among the BHV1 deletion mutants that were tested, the gC- mutant stimulated the best cell-mediated immune responses. 相似文献