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Magnetic resonance images of the brain were obtained from 2 gorillas (Gorilla gorilla gorilla), 4 orangutans (Pongo pygmaeus), 14 chimpanzees (Pan troglodytes), and 4 bonobos (Pan paniscus), The region on the motor cortex of humans identified as responsible for motor skill of the hand (the "knob") was identified in this sample on consecutive 1-mm axial scans. The shape of the knob area was traced on each scan from both hemispheres, and the area from all scans was summed to calculate the knob volume. The width of the knob was also measured and correlated highly with knob volume. A significant population-level leftward asymmetry in the volume and width of the knob was revealed (p? 相似文献
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DF Brown MJ Muirhead PM Travis SR Vire J Weller M Hauer-Jensen 《Canadian Metallurgical Quarterly》1997,80(5):966-972
BACKGROUND: Few reports have been made regarding the long term safety of implantable venous access devices used for the delivery of chemotherapeutic agents. The authors' goals were to determine the frequency of complications in patients receiving chemotherapy with these devices; to determine whether complications were associated with the mode of chemotherapy delivery (push/bolus or infusional regimens); and to evaluate the influence of other risk factors, including home-based versus hospital-based administration. METHODS: A total of 152 oncology patients at the John L. McClellan Memorial Veterans Administration Medical Center in Little Rock, Arkansas (ages 26-81 years; mean age, 62 years), who underwent surgical placement of an Infus-a-Port (Strato, Inc., Beverly, MA) between May 1, 1992 and May 31, 1994, were evaluated retrospectively for postplacement device complications, such as infection, thrombosis, and mechanical failure. RESULTS: Twenty-seven patients experienced 1 complication each: 17 episodes of device-related sepsis, cellulitis, or fever of unknown origin; 8 episodes of thrombosis or catheter occlusion; 1 episode of drug extravasation; and 1 mechanical failure. Patient age, frequency of port accession, mode of chemotherapy delivery, tumor type, and neutropenia were evaluated as risk factors, but none was statistically significant. Complications were more frequent during the first 90 days after implantation, but they continued to occur throughout the observation period. CONCLUSIONS: Complications attributable to an implantable venous access device were infrequent in this patient population. No differences in complications for patients receiving home-based versus hospital-based chemotherapy administration were noted, opening the possibility of significant time and cost savings with home treatment. 相似文献
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OBJECTIVE: The objectives of this study were to know the prevalence of hepatitis C virus (HCV) in a population of pregnant women, to evaluate the vertical transmission rates of HCV in a prospective study and to determine the repercussions and consequences in children born to infected mothers. PATIENTS AND METHODS: A total of 6556 pregnant women were tested for HCV antibodies from January 1993 to August 1995. We followed 50 babies born to infected mothers for at least 12 months (mean 15 months). Serological assays employed included a screening ELISA II confirmed with immunoblot. Viral detection was performed by qualitative and quantitative PCR for HCV-RNA. RESULTS: Fifty-nine pregnant women were AcHCV(+). This represents a seroprevalence of 0.9%. Of the 50 babies followed, 6 were PCR(+) and 44 were PCR(-). The risk of transmission is correlated with the titer of HCV-RNA in the mother. All mothers of infected babies were HIV (-). CONCLUSIONS: The rate of prevalence in our pregnant women population is 0.9%. We found a vertical transmission rate of 12%. The high serum HCV-RNA titers in the mothers are a risk factor of transmission of HCV. The viremia in the children does not predict the apparition of the clinical disease, although they can exhibit intermittent increases of transaminases. 相似文献
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JR Kirsch A Bhardwaj LJ Martin DF Hanley RJ Traystman 《Canadian Metallurgical Quarterly》1997,28(11):2259-64; discussion 2264-5
BACKGROUND AND PURPOSE: We attempted to determine whether N-nitro-L-arginine methyl ester (L-NAME) would improve neurological outcome and whether L-arginine (L-ARG) would worsen neurological outcome after transient global ischemia. METHODS: Halothane-anesthetized cats (n = 6 for each group) were treated with intravenous saline, L-NAME (5 mg/kg or 10 mg/kg), or L-arginine (300 mg/kg) 30 minutes before 10 minutes of ischemia (temporary ligation of the left subclavian and brachiocephalic arteries with hemorrhagic hypotension to 50 mm Hg). At 30 minutes of reperfusion, cats in the L-ARG group were administered an additional 300 mg/kg dose of intravenous L-arginine. RESULTS: Time (mean +/- SE) to isoelectric electroencephalography was similar among groups (saline, 26 +/- 11 seconds; L-NAME-5, 15 +/- 4 seconds; L-NAME-10, 36 +/- 27 seconds; and L-ARG, 22 +/- 7 seconds). At 72 hours, reperfusion pathological injury was severe and neurological deficit score (mean, range) was similar among groups (saline, 38[11 to 70]; L-NAME-5, 52 [40 to 73]; L-NAME-10, 47 [23 to 70]; and L-ARG, 40 [0 to 79]). CONCLUSIONS: Nitric oxide is not important in the mechanism of brain injury after global ischemia in cats. 相似文献
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R. J. Hopkins A. N. E. Birch D. W. Griffiths R. Baur E. Städler R. G. Mckinlay 《Journal of chemical ecology》1997,23(3):629-643
The role of leaf surface compounds influencing the oviposition of the turnip root fly, Delia floralis, was investigated using bioassays and fractionation of leaf surface extracts from four Brassica genotypes. Polar leaf surface extracts contained between 65 and 175 nM/g leaf equivalent of glucosinolates. However, following fractionation it was found that nonglucosinolates were the major stimuli for D. floralis oviposition. Electrophysiological studies of leaf surface extracts and their fractions were performed by using D. radicum, the cabbage root fly, as an analytical tool. The most behaviorally active fractions contained stimulatory compound(s) that had an activity profile identical to that previously described for recently discovered nonglucosinolate compounds. The role of leaf surface chemicals in influencing antixenotic resistance to D. floralis is discussed. 相似文献
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