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71.
VP Vassilikos R Lim I Kreidieh AW Nathan SJ Edmondson GM Rees SO Banim DS Dymond 《Canadian Metallurgical Quarterly》1997,8(11-12):705-709
BACKGROUND: Elderly patients with ischaemic heart disease are often treated more conservatively and for longer than younger patients, but this strategy may result in subsequent invasive intervention of more advanced and higher risk coronary disease. METHODS: We performed a retrospective analysis of 109 patients aged > or = 70 years (mean age 74 years, 66% men), who presented with angina refractory to maximal medical treatment or unstable angina over a 2-year period (1988-1990), to compare the relative risks and benefits of myocardial revascularisation [coronary artery bypass grafting (CABG) and percutaneous transluminal coronary angioplasty (PTCA)] in this higher-risk age group. RESULTS: Sixty patients underwent CABG and 49 patients PTCA. There were eight periprocedural deaths in total (six in the CABG group, and two in the PTCA group, P = 0.29). Six patients in the CABG group suffered a cerebrovascular accident (two fatal). Acute Q-wave myocardial infarction occurred in one patient in the CABG group and in two patients in the PTCA group. The length of hospital stay was longer for the CABG group (CABG group 11.4 +/- 5.4 days, range 7-30 days, PTCA group 7.4 +/- 7.6 days, range 1-39 days, P = 0.01). Outcome was assessed using the major cardiac event rate (MACE; i.e. the rate of death, myocardial infarction, repeat CABG or PTCA). The cumulative event-free survival in the CABG group in 1, 2 and 3 years was 87, 85 and 85%, respectively. In contrast, in the PTCA group it was 55, 48 and 48% (P = 0.0001). Age, sex, number of diseased vessels, degree of revascularisation and left ventricular function were not predictive of the recurrence of angina in both groups. Actuarial survival (total mortality, including perioperative mortality) was lower at 1 year in the CABG group due to the higher perioperative mortality, but similar in both groups after the second year (P = 0.62). CONCLUSIONS: Elderly patients with refractory or unstable angina who are revascularised surgically have a better long-term outcome (less frequent event rate of the composite end-point--myocardial infarction, revascularisation procedures and death) compared with those who are revascularised with PTCA. This benefit is been realised after the second year. Total mortality is similar in both groups after the second year. Therefore elderly patients who are fit for surgery should not be denied the benefits of CABG. PTCA may be regarded as a complementary and satisfactory treatment, especially for those whose life expectancy is limited to less than 2 years. The use of stents may improve outcome in the PTCA group and this needs to be evaluated. 相似文献
72.
KS Caldemeyer VP Mathews MK Edwards-Brown RR Smith 《Canadian Metallurgical Quarterly》1997,18(1):107-109
In an 11-year-old immunocompetent girl with protracted cryptococcal infection of the central nervous system, CT showed multiple areas of parenchymal calcification. MR imaging showed large gelatinous pseudocysts around the brain stem. These imaging features and the child's age are unusual for intracranial cryptococcosis. 相似文献
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74.
The authors studied efficacy and safety of ceftriaxone given intravenously for 3-4 weeks in a dose 2-4 g/day to patients with streptococcal endocarditis (SE). Of them, 8, 8 and 1 patients were infected with Streptococcus viridans, Streptococcus pyogenes, Pneumococcus, respectively. Hospital trial and follow-up lasted up to 2 years. Cure without surgical correction occurred in 7 patients, valvular replacement was needed in 4 patients, 1 patient died, 4 patients developed recurrences 3 and more months after therapy with ceftriaxone. The drug was safe and well tolerated. 33% of the patients were discharged from hospital with obvious improvement after 2-3 week treatment to continue it outpatiently for 1-2 weeks. 相似文献
75.
The present study employed intramuscular (i.m.) injections of the acetylcholine (ACh) receptor antagonist scopolamine hydrobromide (0.10 mg/kg) to investigate the possible involvement of ACh in naturally occurring spatial navigation in homing pigeons (Columba livia). Control pigeons receiving injections of saline or scopolamine methylbromide, an ACh antagonist that does not cross the blood-brain barrier, were oriented in a homeward direction when released from a location 8 km from home. In contrast, pigeons injected with scopolamine hydrobromide (0.10 mg/kg, i.m.) were less well oriented and took more time to return home from the same location. These results suggest that homing pigeon navigation is regulated, in part, by central cholinergic mechanisms. 相似文献
76.
KN Srinivasan KV Pugalendi G Sambandam M Ramakrishna Rao S Krishnan VP Menon 《Canadian Metallurgical Quarterly》1998,275(2):197-203
Between 1957 and 1993, the Siberian Chemical Complex (Tomsk-7) located in the Tomsk region (Russia) regularly discharged radioactive liquid wastes into the Tom River which resulted in an extensive contamination of large territories with long lived radionuclides such as cesium-137 and strontium-90. In the summers of 1996 and 1997, Research Team of Siberian Medical University conducted biodosimetry and cytogenetic monitoring of pikes (Esox lucius) caught in the Tom River at various distances downstream from the Siberian Chemical Complex (SCC) using the micronucleus test and the gamma spectroscopy. Our findings demonstrated that the difference in frequency of micronucleated erythrocytes between the radiation-exposed fish caught downstream from the SCC and the controls was statistically significant (P < 0.01). Moreover, we found a good correlation between radiocesium concentration and micronucleated erythrocyte frequency in pikes. It was found that both the micronucleated erythrocyte frequency in pike blood and the level of the pike radiocesium concentration depended on the age of pikes. The micronucleated erythrocyte frequency gradually increased from the 1-year-old pikes to the over 20-year-old pikes. On the other hand, the average level of radiocesium concentration gradually increased from the 1-year-old pikes only up to the 10-year-old pikes. There is no correlation between radiocesium concentration and micronucleated erythrocyte frequency in the over 10-year-old pikes. 相似文献
77.
Hybrid F1 mice derived from inbred parental mouse strains are extensively used as animal models of human autoimmune diseases and transplantation. It is generally believed that with regard to immunologic studies, hybrid F1 mice behave in a consistent manner, equivalent to any other inbred mouse strain. In this study, we report that in comparison to inbred parental strains, individual hybrid F1 mice revealed a broad heterogeneity of proliferative response to the immunodominant determinants within hen eggwhite lysozyme (HEL). Of five parental strains tested, individual mice of three strains responding to only a few dominant HEL determinants (B6, BALB/c, and B10.PL) showed quite homogeneous patterns of response, whereas two mouse strains responsive to several determinants of HEL revealed either relative homogeneity (CBA/J mice) or heterogeneity (SJL mice) of response. However, in SJL mice, responses to major, dominant determinants of HEL were quite consistent. On the contrary, regardless of the consistency of response of parental strains, all three of F1 mice [[B6 x BALB/c]F1, [B6 x CBA/J]F1, and [SJL x B10.PL]F1] revealed significantly greater heterogeneity of response, which even involved the major, dominant determinants of HEL. We attribute the above heterogeneity of response to the competitive as well as aleatory nature of the interaction between various factors, including the coexistence of different MHC (parental as well as hybrid MHC) molecules, determinant capture, and the T cell repertoire. These results have important implications for studies on autoimmunity, infection, and vaccine design in human populations, where heterozygosity is the norm rather than the exception. 相似文献
78.
NI Kurysheva MI Vinetskaia VP Erichev VP Artamonov AP Uspenskaia 《Canadian Metallurgical Quarterly》1998,114(6):3-6
The paper focuses on the history and sources of origin of sanology as science, with its brief characterization being given, relating to such items as definition, object and subject of investigation, methodological approaches and tasks, with special emphasis being placed on the significance of sanology in the elaboration of general theory of medicine. 相似文献
79.
80.
VP Dave R Keefe MA Berger K Drbal JA Punt DL Wiest B Alarcon DJ Kappes 《Canadian Metallurgical Quarterly》1998,10(10):1481-1490
CD3delta-deficient (delta degrees) mice are defective in alphabeta T cell development. Here we explore the capacity of TCR-CD3 signaling complexes expressed on delta degrees thymocytes to mediate the following functional outcomes in response to antibody cross-linking: (i) the transition from the CD4-CD8- to CD4+CD8+ stage, (ii) the transition from the CD4+CD8+ to CD4+CD8- or CD4-CD8+ stages and (iii) the induction of apoptosis. We provide evidence that CD3deltaepsilon complexes are dispensable for mediating the anti-CD3-mediated CD4-CD8- to CD4+CD8+ transition. On the other hand, CD3delta is critical at the CD4+CD8+ stage. We demonstrate that CD4+CD8+ thymocytes from delta degrees mice, unlike delta degrees CD4-CD8- thymocytes and wild-type CD4+CD8+ thymocytes, require prolonged or consecutive stimuli to elicit functional responses. Depending on the nature of the secondary stimulus, delta degrees thymocytes can be induced to undergo apoptosis or preferential maturation to the CD4-CD8+ stage. Taken together these results indicate that the signaling capacity of the TCR-CD3 complex is noticeably altered in the absence of CD3delta. The essential role of CD3delta at the CD4+CD8+ stage of development correlates with the onset of TCRalpha rearrangement, consistent with a critical structural and/or functional relationship between CD3delta and TCRalpha. 相似文献