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991.
SN Ameratunga RN Norton SW MacMahon GS Smith RT Jackson R Currie JD Langley SS Sharpe A Cheng DG Woodfield 《Canadian Metallurgical Quarterly》1998,22(5):578-582
Blood donors have made important contributions to research, most notably in cross-sectional seroprevalence studies. The proposed New Zealand Blood Donors Health Study is a prospective cohort study of 30,000 New Zealand donors designed to investigate the determinants of common injuries, cardiovascular disease and cancer. While robust from an analytic perspective, the execution of prospective cohort studies in many settings is impeded by methodological, economic and organisational barriers. We examined the operational considerations of implementing a large-scale cohort study at a transfusion centre and evaluated measures taken to optimise data collection procedures. A pilot study of 1,000 participants revealed donor motivation to participate in this research was high (91% response rate). Comprehensive exposure data on lifestyle, behavioural and psychosocial factors were obtained from 95% of participants. Substantial heterogeneity in levels of potential risk factors was noted among respondents. Detailed dietary habit information and a study blood sample were obtained from 67% and 100% of participants, respectively. Study recruitment and baseline data collection was feasible during routine donor visits with minimal interruption to donor centre staff and procedures. We conclude the study design and characteristics of the regional donor program enhance the efficiency and significance of the proposed research. 相似文献
992.
993.
994.
AN Inozemtsev SS Trofimov GG Borlikova FA Firova LL Pragina TA Gudasheva RU Ostrovskaia NA Tushmalova TA Voronina 《Canadian Metallurgical Quarterly》1998,61(3):10-12
Endothelium protector SOFTEL is developed by Ekran firm and Institute of Eye Diseases, Russian Academy of Medical Sciences. The drug was used in 157 patients aged 28-79 years. Perforating keratoplasty for corneal leukoma and keratoconus was carried out in 46 patients, cataract extraction with implantation of intraocular lens (IOL) in 94, and cataract extraction without IOL implantation in 17 patients. Two patients developed slight hypertension in the postoperative period, which resolved within 24 h, and four patients developed moderate corneal edema persisting for 1-2 days postoperation. The protective effect of softel is compatible with that of its foreign analog Healon. The drug is effective in cataract extractions with IOL implantation and perforating keratoplasty. 相似文献
995.
KK Nobuhara ML Ferretti AM Siddiqui SS Kim ST Treves JM Wilson 《Canadian Metallurgical Quarterly》1998,33(7):1024-8; discussion 1028-9
BACKGROUND/PURPOSE: We have demonstrated previously that postnatal lung growth can be accelerated by continuous intrapulmonary distension with perfluorocarbon (PFC). The purpose of this study was to examine the effect of PFC distension on long-term lung function and to determine if shorter periods of lung distension would be sufficient to stimulate growth. METHODS: Eight neonatal lambs underwent a right thoracotomy. The superior segment of the right upper lobe of the experimental group (n = 5) was isolated and distended with PFC to an intrabronchial pressure of 7 to 10 mm Hg. The inferior segment was removed. After a 7-day distension period (the maximum period of exposure currently allowed for humans), the experimental animals underwent removal of the intrabronchial catheter and surgical closure of the bronchial stump. Control animals (n = 3) underwent right upper lobe inferior segmentectomy alone. Animals were allowed to breathe spontaneously and reach 3 to 6 months of age. Before death, all animals were evaluated by chest radiographs and ventilation-perfusion scans. Pulmonary venous blood gas levels were obtained. Lungs were harvested and airway fixed for morphometric analysis. RESULTS: Chest radiographs of the experimental group showed variable amounts of intrapleural and interstitial PFC but were otherwise normal. Results of ventilation/perfusion (VQ) scans of all experimental animals were normal. On retrieval, the right upper lobe of experimental animals appeared slightly hyperinflated compared with controls. Right upper lobe pulmonary vein PaO2 to left pulmonary vein PaO2 ratio was comparable in experimental and control animals (1.2 +/- .41 v 0.92 +/- .15). DNA to protein ratios were slightly higher in the right upper lobes of experimental animals, however, the difference was not statistically significant (.64 +/- .11 v .42 +/- .03). On histological evaluation, the airway epithelium and alveoli of the right upper lobe of experimental animals appeared normal. Lung morphometry results showed no statistically significant differences in alveolar number between experimental and control animals. CONCLUSIONS: From these preliminary data we conclude that (1) lung architecture is preserved in juvenile animals subjected to intrapulmonary PFC distension as neonates, (2) lung function is preserved in the lobar segment after PFC distension, and (3) intrapulmonary PFC distension appears to be safe at 3 to 6 months follow-up. However, 7 days of PFC distension is insufficient to promote lung growth. 相似文献
996.
O Eton DD Kharkevitch MA Gianan MI Ross K Itoh MW Pride C Donawho AC Buzaid PF Mansfield JE Lee SS Legha C Plager NE Papadopoulos AY Bedikian RS Benjamin CM Balch 《Canadian Metallurgical Quarterly》1998,4(3):619-627
Advances in transdermal therapeutic systems (TTS) and the technology involved have been rapid because of the sophistications of physiology and biology on skin, enhancing methodology for the skin penetration of drugs, and material and polymer sciences on the pharmaceutical additives. In this review paper, such progress was introduced and the future on the TTS was augured. 相似文献
997.
KD McKeegan LA Leshin SS Russell GJ MacPherson 《Canadian Metallurgical Quarterly》1998,280(5362):414-418
The oxygen isotopic compositions of two calcium-aluminum-rich inclusions (CAIs) from the unequilibrated ordinary chondrite meteorites Quinyambie and Semarkona are enriched in 16O by an amount similar to that in CAIs from carbonaceous chondrites. This may indicate that most CAIs formed in a restricted region of the solar nebula and were then unevenly distributed throughout the various chondrite accretion regions. The Semarkona CAI is isotopically homogeneous and contains highly 16O-enriched melilite, supporting the hypothesis that all CAI minerals were originally 16O-rich, but that in most carbonaceous chondrite inclusions some minerals exchanged oxygen isotopes with an external reservoir following crystallization. 相似文献
998.
JE Blaney E Nobusawa MA Brehm RH Bonneau LM Mylin TM Fu Y Kawaoka SS Tevethia 《Canadian Metallurgical Quarterly》1998,72(12):9567-9574
We have evaluated the potential of conferring protective immunity to herpes simplex virus type 2 (HSV-2) by selectively inducing an HSV-specific CD8(+) cytotoxic T-lymphocyte (CTL) response directed against a single major histocompatibility complex class I-restricted CTL recognition epitope. We generated a recombinant vaccinia virus (rVV-ES-gB498-505) which expresses the H-2Kb-restricted, HSV-1/2-cross-reactive CTL recognition epitope, HSV glycoprotein B residues 498 to 505 (SSIEFARL) (gB498-505), fused to the adenovirus type 5 E3/19K endoplasmic reticulum insertion sequence (ES). Mucosal immunization of C57BL/6 mice with this recombinant vaccinia virus induced both a primary CTL response in the draining lymph nodes and a splenic memory CTL response directed against HSV gB498-505. To determine the ability of the gB498-505-specific memory CTL response to provide protection from HSV infection, immunized mice were challenged with a lethal dose of HSV-2 strain 186 by the intranasal (i.n.) route. Development of the gB498-505-specific CTL response conferred resistance in 60 to 75% of mice challenged with a lethal dose of HSV-2 and significantly reduced the levels of infectious virus in the brains and trigeminal ganglia of challenged mice. Finally, i.n. immunization of C57BL/6 mice with either a recombinant influenza virus or a recombinant vaccinia virus expressing HSV gB498-505 without the ES was also demonstrated to induce an HSV-specific CTL response and provide protection from HSV infection. This finding confirms that the induction of an HSV-specific CTL response directed against a single epitope is sufficient for conferring protective immunity to HSV. Our findings support the role of CD8(+) T cells in the control of HSV infection of the central nervous system and suggest the potential importance of eliciting HSV-specific mucosal CD8(+) CTL in HSV vaccine design. 相似文献
999.
1000.
S Chua S Arulkumaran C Chow G Kumarasinghe N Selamat BG Kuah SS Ratnam 《Canadian Metallurgical Quarterly》1995,36(4):383-385
The authors report a case of pleural fibroma discovered during an examination for thoracic pains in a 65 year old woman. Histochemical studies were positive with vimentin and negative with KL1 antibodies and compatible with the most recent hypotheses concerning the purely fibroblastic origin of these tumours. 相似文献