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31.
32.
Meningitis and cerebrospinal fluid (CSF) leak are serious complications of acoustic tumor surgery. Previous reports have varied in the incidence of and the predisposing factors to these complications. This study reviews a series of 723 acoustic tumors removed via the translabyrinthine approach at the House Ear Clinic in Los Angeles. The incidences of CSF leak and meningitis were 6.8% and 2.9%, respectively. The patients who developed these problems were compared to the remainder of the study population for differences in age at surgery, tumor size, operative time, and length of hospital stay. Meningitis occurred more frequently in larger tumors, and patients with either complication had a longer hospital stay. The presence of CSF leak did not predispose to meningitis. It is concluded that technical factors account for postoperative CSF leak and meningitis after translabyrinthine acoustic tumor removal. 相似文献
33.
Quantitative X-ray diffraction analysis of urinary calculi by use of the internal-standard method and reference intensity ratios 总被引:1,自引:0,他引:1
The internal-standard method and the powder diffractometer have been applied here to the quantitative determination of urinary stone constituents by x-ray diffraction (XRD). Reference intensity ratios determined for six stone substances were used in the reduction of intensity data. Constituent concentrations calculated for 21 stones were compared with values obtained from an element-sensitive technique. We conclude that XRD analysis alone cannot be regarded as a routine technique for the quantitative characterization of uroliths, but that semiquantitative XRD analysis supplemented by accurate quantitative elemental data is more suitable for the precise determination of true stone composition. 相似文献
34.
Emery M Rodgers MM Boerman J Fleming BC Howe J Pope M 《The Journal of orthopaedic and sports physical therapy》1989,10(11):441-447
This research was supported by a grant from The Foundation for Physical Therapy, Alexandria, VA. The purpose of this study was to determine the reliability of a quantitative measure of knee ligament laxity in vivo. The testing device simultaneously measures applied forces and resulting displacement at the knee through use of a multidimensional electrogoniometer, dynamometer, and a computer-assisted analysis system. Subjects were 30 females and 20 males, ranging in age from 18-32 years. Laxity tests were performed in the anterior/posterior (A/P) plane at 90 and 30 degrees of knee flexion, and the varus/valgus (V/V) plane at 20 and 0 degrees of knee flexion. Test-retest (N = 41) and intertester (N = 18) repeatability was assessed in all test positions by ANOVA and by coefficients of correlation and variability. No significant differences were found within testers for A/P or V/V tests 1 week apart at any angle tested. There were significant differences between testers for A/P and V/V tests. No significant differences were found between left and right sides, or between male/female values. Comparisons to other in vitro and in vivo studies are made. J Orthop Sports Phys Ther 1989;10(11):441-447. 相似文献
35.
Hormonal fluctuations associated with the menstrual cycle influence
appetite control and eating behaviour. Energy intake varies during the
reproductive cycle in humans and animals, with a periovulatory nadir and a
luteal phase peak. Patterns of macronutrient selection show less
consistency but a number of studies report carbohydrate cravings in the
premenstrual phase, particularly in women with premenstrual syndrome. The
cyclical nature of food cravings are frequently, but not invariably,
associated with depression. Fluctuations in appetite, cravings and energy
intake during the menstrual cycle may occur in parallel with cyclical
rhythms in serotonin, which can be accompanied by affective symptoms. The
premenstrual phase can be considered as a time when women are especially
vulnerable to overconsumption, food craving and depression; this is often
associated with low serotonin activity.
相似文献
36.
This study examined the relationship between exercise motives and physical self‐esteem (PSE) in physically active females using Self‐Determination Theory (SDT; Deci & Ryan, 1985, 1995; Ryan & Deci, 2000). Female exercise participants recruited from university‐based exercise classes reported their motives for exercise during Week 2, and their levels of PSE during Week 12, of a 15‐week exercise class. Bivariate correlations indicated that exercise motives displayed a graded pattern of relationships. They also suggested that only autonomous exercise motives were associated with higher PSE. Discriminant function analysis revealed that more autonomous exercise motives correctly classified 83.3% of the high PSE group and 88.9% of the low PSE group. These findings support Ryan and Deci's assertions and suggest that autonomous exercise motives may play an important role in positive PSE in the exercise domain. These findings advance the application of SDT in the exercise domain and further our understanding of PSE development. 相似文献
37.
Telfer JF; Thomson AJ; Cameron IT; Greer IA; Norman JE 《Human reproduction (Oxford, England)》1997,12(10):2306-2312
Superoxide, an agent which attenuates the half-life of nitric oxide, is
metabolized and synthesized by superoxide dismutase (SOD) and xanthine
oxidase, respectively. Over the last few years much work has focused on the
role of nitric oxide in human parturition. The aim of this study was to
determine whether the onset of human parturition is associated with a
change in the expression of copper/zinc superoxide dismutase (Cu/Zn SOD),
manganese superoxide dismutase (Mn SOD) or xanthine oxidase within the
uterus. Samples of myometrium, placenta, decidua and fetal membranes were
obtained from women before and after the onset of labour at term.
Immunocytochemistry was used to localize Cu/Zn SOD, Mn SOD and xanthine
oxidase and measure SOD enzyme activity. Cu/Zn and Mn SOD-like
immunoreactivity was detected in syncytiotrophoblast cells, villous stromal
cells and endothelial cells of blood vessels in the placenta. In the
myometrium Cu/Zn and Mn SOD were localized to myocytes and endothelial
cells and to some vascular smooth muscle cells. In the fetal membranes we
observed staining for Cu/Zn SOD and Mn SOD in the amnion, chorion,
extravillous trophoblast and decidua. There was no difference in SOD enzyme
activity or staining intensity for SOD between different cell types before
and during labour. Xanthine oxidase immunoreactivity was identified in each
of the tissues examined and again there was no difference in immunostaining
in tissues obtained from women delivered before or after the onset of
labour. These results show that the pregnant uterus is capable of both
synthesizing and degrading superoxide and suggest that superoxide dismutase
and xanthine oxidase may play a role in the maintenance of uterine
quiescence during pregnancy, but not in the initiation of parturition.
相似文献
38.
The Role of Sialic Acid in Opsonin-Dependent and Opsonin-Independent Adhesion of Listeria monocytogenes to Murine Peritoneal Macrophages
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Srinivas Maganti Marcia M. Pierce Alex Hoffmaster Frank G. Rodgers 《Infection and immunity》1998,66(2):620-626
The adhesion of listeriae to host cells employs mechanisms which are complex and not well understood. Listeria monocytogenes is a facultative intracellular pathogen responsible for meningoencephalitis, septicemia, and abortion in susceptible and immunocompromised individuals. Subsequent to colonization and penetration of the gut epithelium, the organism attaches to resident macrophages and replicates intracellularly, thus evading the humoral immune system of the infected host. The focus of these studies was to investigate the attachment of the organism to murine peritoneal macrophages in an opsonin-dependent and opsonin-independent fashion. Assessment of competitive binding experiments by immunofluorescence and enzyme-linked immunosorbent assays showed that adhesion of the organism to macrophages in the presence or absence of opsonins was inhibited (90%) by N-acetylneuraminic acid (NAcNeu). In addition, the lectin from Maackia amurensis, with affinity for NAcNeu-α(2,3)galactose, blocked binding of L. monocytogenes to host cells. Oxidation of the surface carbohydrates on the organism by using sodium metaperiodate resulted in a dose-dependent reduction (up to 98%) in adherence to macrophages. Monoclonal antibody to complement receptor 3 did not prevent listeriae from binding to mouse macrophages or from replicating within the infected cells whether or not normal mouse serum was present. Based on our results, we propose the involvement of NAcNeu, a member of the sialic acid group, in the attachment of L. monocytogenes to permissive murine macrophages. 相似文献
39.
Comparisons between direct microscopic and cultural methods for recognition of Corynebacterium vaginale in women with vaginitis.
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The frequency with which clue cells could be detected in Gram-stained vaginal smears and/or cervical Papanicolaou (Pap) smears was compared with the frequency of Corynebacterium vaginale (Haemophilus vaginalis) isolation in a group of 236 female patients, of whom 221 had vaginitis. Vaginal clue cells were found most often in women from whom C. vaginale was isolated (P = 0.00006) whereas, conversely, clue cells in cervical Pap smears were reported more frequently in women with negative cultures for this organism (P = 0.006). C. vaginale isolations were made more frequently from women with both vaginal and cervical clue cells reported (P = 0.000088). However, the combined false positive-false negative vaginal clue cell rate in the patients studied was 36.5%. Neither the detection of vaginal clue cells nor the isolation of C. vaginale was significantly affected by whether or not patients had trichomoniasis (P = 0.25). Trichomonas vaginalis detection in cervical Pap smears and vaginal isolation were related (P = 0.00005), whereas the same relationship was not significant for fungi (P = greater than 0.05). 相似文献
40.
Social conflict in mice is associated with at least two forms of analgesia. A long-lasting opioid reaction is evident in intruder mice exposed to prolonged attack, whilst an acute non-opioid analgesia is seen in response to either defeat experience per se or the territorial scent-marking of an aggressive conspecific. Recent work from this laboratory has suggested that the non-opioid analgesic reaction to defeat experience may be mediated via benzodiazepine receptor mechanisms. The present studies were designed to further test this tentative hypothesis. Results confirmed that defeat analgesia is dose-dependently blocked by Ro15-1788 (20-40 mg/kg) and diazepam (2-4 mg/kg), and also indicated partial antagonism of the reaction by CGS8216 (2.5 mg/kg). The partial agonists CGS9896 (2.5-20 mg/kg) and ZK91296 (2.5-20 mg/kg) were ineffective in blocking the reaction, a finding also obtained with the full agonist ZK93423 (0.05-10 mg/kg). However, the antagonist/weak inverse agonist ZK93426 was found to possess significant intrinsic analgesic activity (10 mg/kg) and to enhance defeat analgesia (5-10 mg/kg). Although several interpretative frameworks for the current pharmacological profile are considered, it is concluded that full clarification of the substrates of defeat analgesia must await further investigations. 相似文献