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991.
TA Fuess ES Hafen P Haridas RI Hulsizer T Junk A Levy C Milstene IA Pless I The RK Yamamoto D Brick K De M Widgoff D Alyea F Grard R Dolfini S Ratti M Kalelkar R Plano P Stamer S Dado J Goldberg R Heifetz J Grunhaus W Bugg T Handler E Hart Y Eisenberg U Karshon 《Canadian Metallurgical Quarterly》1987,35(11):3297-3309
992.
CG Wible ME Shenton IA Fischer JE Allard R Kikinis FA Jolesz DV Iosifescu RW McCarley 《Canadian Metallurgical Quarterly》1997,76(1):29-40
NMR spectroscopy and NMR imaging with magnetic field gradients make strange bedfellows, the requirements for one seemingly ruling out the other for human applications. Nevertheless, their stories are intertwined; the advent of high field imaging systems arose because of the desire for human spectroscopy. Localized spectroscopy is possible because of NMR imaging. Both have links to physics at Nottingham, at least in the personalized account that follows. Today, virtually all NMR spectroscopy experiments can be conceived with a localized in vivo spectroscopy counterpart. 相似文献
993.
EB Sungurov VV Peresedov ED Markova IA Ivanova-Smolenskaia OIu Rebrova VM Tiurnikov 《Canadian Metallurgical Quarterly》1998,(4):21-3; discussion 23-4
The paper describes stereotactic operations made in 278 patients with different forms of torsion dystonia during 20 years. Late outcomes were studied and assessed in 130 patients. The duration of follow-ups was 3 to 23 years. The patients' mean age at surgery was 30.5 years. The indications for surgical treatment were ineffective medical treatment and progressive disease. Positive early and late postoperative outcomes were achieved in 93 and 70% of patients, respectively. Complications developed in 3.2 and 12.3% of patients after the first and second operations, respectively. The positive outcome depends on the form, etiology, the destructible structure or a complex of structures. Surgical treatment of patients with torsion dystonia by stereotactic operations on basal ganglia is an effective treatment that provides a steady-state positive result in 70% of patients in the late period. 相似文献
994.
Two glucose transporter (GLUT) isoforms have been identified in brain. The GLUT1 isoform is abundant in cerebral microvessels and may be present in glia and neurons, whereas GLUT3 is probably the major neuronal glucose transporter. This study investigates whether GLUT3 is also present in microvessels from rat, human, and canine brain, by means of antisera directed against the divergent C-terminal sequences of mouse and human GLUT3. GLUT1 was detected in whole brain as two molecular mass forms: 55 kDa in microvessels and 45 kDa in cortical neuronal/glial membranes. With the aid of the appropriate antisera to the species-specific sequences, GLUT3 was detected in rat and human cortical membranes but not in isolated rat or human microvessels. These antisera failed to detect GLUT3 in either canine cortical membranes or canine microvessels, implying additional species specificity in the C-terminal sequence. 相似文献
995.
The abundance and the distribution of Dactylogyrus extensus and Ichthyophthirius multifiliis on gills of two-years old carps have been investigated. It has been established that at least there are five groups, which differs from each other on the asymmetry of infection. 相似文献
996.
LM Trimpeneers IA Wijgaerts NA Grognard LR Dermaut PA Adriaens 《Canadian Metallurgical Quarterly》1997,111(5):492-497
OBJECTIVES: To determine persistence of bacteremia, pathogenicity, and immunoglobulin kinetics after blood transmission of Bartonella henselae in cats. ANIMALS: 18 specific-pathogen-free (SPF) cats (16 weeks old) received blood or urine from 4 adult cats (2 SPF, 2 naturally infected with B henselae). PROCEDURE: SPF cats were inoculated with blood IV (n = 4), blood IM (n = 4), or urine sediment IM (n = 4) from 2 bacteremic cats (donors A and B). Control cats (2/route) received inoculum from culture-negative, seronegative SPF cats (donors C and D). RESULTS: 6 cats (5 blood, 1 urine) were transiently febrile during the 213-day observation period. Two bacteremic cats developed CNS abnormalities. Transient anemia was the only hematologic abnormality. Bacteremia was induced in 7 of 8 blood recipients by postinoculation day (PID) 11. Urine recipients (n = 6) did not become bacteremic or seroconvert by PID 108, but when challenge exposed IV with blood, 4 of 6 became infected. All infected cats developed relapsing bacteremia. Initially, colony counts for donor-A recipients were 10(3) greater than those for donor-B recipients; however, during relapses, counts were similar. Polymerase chain reaction-restriction fragment length polymorphism analysis of 16S rRNA gene and the intergenic spacer region revealed no differences among isolates derived from recipient cats. Bartonella henselae-specific antibodies were detected between PID 15 and 18 in donor-A, compared with PID 46 and 181 in donor-B recipients. The peak geometric mean titer of donor-A recipients was 1,448, versus 406 for donor-B recipients. CONCLUSIONS AND CLINICAL RELEVANCE: Blood transmission of B henselae induced subtle clinical abnormalities; the biological behavior of the 2 donor strains differed; and relapsing bacteremia can persist in conjunction with variably high antibody titers. 相似文献
997.
Up-to-date work conditions of open extraction of gold in Far North are characterized by some occupational hazards, among which noise and vibration are leaders. In severe climate conditions heat state of the workers was considered exceeding the allowable standards. The authors suggest recommendations to normalize working environment of the enterprises under study. 相似文献
998.
FZ al-Faleh F Sbeih M al-Karawi IA al-Mofleh RS al-Rashed A Ayoola S al-Amri I Mayet TM al-Habbal A al-Omair MO al-Sohaibani AO Abdullah SA Mohamed MA el-Sheikh 《Canadian Metallurgical Quarterly》1998,45(20):488-491
BACKGROUND/AIM: Several studies have indicated that there are certain predictive factors (gender, duration of infection with HCV, cirrhosis and genotype of HCV) of a better response with alpha-interferon treatment in patients with chronic hepatitis C. The aim of this study was to evaluate these factors in Saudis and other Arab nationals with chronic hepatitis C-genotype 4-undergoing alpha-interferon treatment. METHODOLOGY: A multicenter study was conducted between 1992 and 1994 on 80 consecutive patients who were prospectively recruited and randomized in treatment and control groups. RESULTS: The results of this multicenter study indicated a low response rate to alpha-interferon with an overall response rate of 43%, of which 28% was complete. The sustained response was only 16%. Among the reasons for this low response in our study are the high percentage of patients with cirrhosis and the long infection interval, as about 80% of our HCV cases were community-acquired. CONCLUSION: Liver cirrhosis was found to be the main predetermining factor for response to interferon treatment. Genotype 4 was not a contributing factor to the difference in response rate. 相似文献
999.
Protein tyrosine kinases Syk and ZAP-70 display distinct requirements for Src family kinases in immune response receptor signal transduction 总被引:1,自引:0,他引:1
Engagement of immunoreceptors in hemopoietic cells leads to activation of Src family tyrosine kinases as well as Syk or ZAP-70. Current models propose that Src family kinases are critical in immune response signal transduction through their role in phosphorylation of tyrosine residues within immunoreceptor tyrosine activation motifs (ITAMs; which recruit the SH2 domains of Syk or ZAP-70) and by direct phosphorylation of Syk and ZAP-70. Several lines of evidence suggest that Syk may not show the same dependence on activation by Src family kinases as ZAP-70. In this report, we used COS cells transiently transfected with components of the Fc epsilon RI complex (Lyn, Syk, and a chimeric CD8 receptor containing the cytoplasmic domain of the gamma subunit of Fc epsilon RI (CD8-gamma)) to examine the regulation of Syk activity. Syk was activated and phosphorylated in COS cells cotransfected with Lyn; however, in cells expressing CD8-gamma, activation of Syk and phosphorylation of CD8-gamma did not require coexpression of Lyn. Additional experiments indicate that gamma phosphorylation is dependent on Syk kinase activity and is independent of endogenous COS cell kinases. In parallel experiments, ZAP-70 was not activated by cotransfection with CD8-gamma, nor was CD8-gamma phosphorylated when coexpressed with ZAP-70 alone. Taken together, these studies indicate that Syk can be distinguished from ZAP-70 in its ability to be activated by coexpression with an ITAM-containing receptor without coexpression of a Src family kinase, and that Syk is capable of phosphorylating ITAM tyrosines under certain experimental conditions. 相似文献
1000.
Population-based analysis of treatment of pancreatic cancer and Whipple resection: Department of Defense hospitals, 1989-1994 总被引:3,自引:0,他引:3
TP Wade IA Halaby DR Stapleton KS Virgo FE Johnson 《Canadian Metallurgical Quarterly》1996,120(4):680-5; discussion 686-7
BACKGROUND: The influence of hospital experience and referral patterns on the operative mortality rate of pancreaticoduodenectomy was studied in a worldwide hospital system. METHODS: We analyzed computerized data on pancreatic cancer patients from U.S. Department of Defense (DOD) hospitals from 1989 to 1994. RESULTS: Six hundred ninety-eight patients had pancreatic cancer, and 130 Whipple operations (105 for pancreatic and 25 for other cancers) were performed with an 8.5% 30-day operative mortality rate. Although most resections were done in teaching hospitals performing more than 1 Whipple procedure per year, their results were not superior to smaller, lower volume nonteaching hospitals. Patients transported for resection were younger than patients undergoing resection at their local DOD hospital but had similar outcomes. The operative mortality rate was higher after unusual resections and with increasing age; the tumor stage had no effect. Unresected patients undergoing combined radiation and chemotherapy had the longest survival times. Radiation therapy was associated with significantly longer survival times in patients without distant metastases, but chemotherapy was associated with a longer survival time when metastases were present. CONCLUSIONS: This mortality rate 8.5% for Whipple resections matches that from other large populations. Equivalent results were obtained in DOD teaching hospitals and smaller, community-type institutions. Because the DOD medical system minimizes financial and logistic barriers to transfer, the even distribution of DOD pancreatectomy mortality suggests that these barriers may favorably influence single institutional outcomes. 相似文献