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31.
JM Bhatavdekar DD Patel N Ghosh PR Chikhlikar TI Trivedi TP Suthar SS Doctor NG Shah DB Balar 《Canadian Metallurgical Quarterly》1997,40(7):785-790
Lanepitant is a high-affinity, selective neurokinin-1 receptor (NK-1) and is effective in the dural inflammation model of acute migraine. Lanepitant 30, 80, and 240 mg given orally was evaluated in a double-blind, placebo-controlled crossover study to determine its effect in reducing migraine pain and severity of associated symptoms. Outpatients treated four migraine headaches of moderate or severe pain intensity with study drug according to a randomization schedule. They recorded their pain intensity and severity of migraine-associated symptoms at 30, 60, 90, and 120 min. Although 53 patients were randomly allocated to a treatment sequence, only 40 patients completed all treatments. There was no statistically significant difference in improvement in migraine pain at any time for any of the treatments. Additionally, there was no change in severity of migraine-associated symptoms associated with lanepitant therapy. No adverse events could be attributed to lanepitant. Lanepitant was ineffective orally in treating acute migraine in this trial. This may be due to poor bioavailability during a migraine attack. Alternatively, the neurogenic inflammation hypothesis may not apply to migraine. 相似文献
32.
The present investigation provide evidences from a non-human primate model that naturally occurring menopause predicts a prominent signature of age-related cognitive decline. Young and aged rhesus monkeys were tested on a delayed response (DR) task known to the sensitive to aging, and reproductive status was evaluated according to menstrual cyclicity and urinary hormone profiles. Peri-/postmenopausal monkeys exhibited significant DR impairments relative to either age-matched premenopausal females, or young control subjects. In addition, markers of endocrine decline in the aged animals were selectively correlated with behavioral performance measures that distinguished premenopausal and peri-/postmenopausal monkeys. These results document that menopause is coupled to cognitive decline in the monkey, and they establish a valuable primate model for defining the effects of endocrine aging on brain and behavioral function. 相似文献
33.
To record brain temperature for comparison with rectal and temporalis muscle temperatures in preliminary studies before MR spectroscopy experiments, a thermistor was inserted into the basal ganglia in eight anesthetized, ventilated, and physiologically monitored rats. The rats were placed in an MR spectrometer and subjected to 60 min of global cerebral ischemia and 2 h of reperfusion without radiofrequency (RF) pulsing. Body temperature was maintained at 37.5-38.0 degrees C (normothermia) or 36.5-37.0 degrees C (mild hypothermia). Brain temperature during ischemia, which dropped to 31.9 +/- 0.3 (hypothermia) and 33.6 +/- 0.5 degrees C (normothermia), correlated with temporalis muscle temperature (r2 = 0.92) but not with body or magnet bore temperature measurements. Ischemia reduced brain temperature approximately 1.7 degrees C in rats subjected to mild hypothermia (1 degree reduction of body temperature). Parallel MR spectroscopy experiments showed no significant difference in energy metabolites between normothermic and hypothermic rats during ischemia. However, the metabolic recovery was more extensive 20-60 min after the onset of reperfusion in hypothermic rats, although not thereafter (P < 0.05). Mild hypothermia speeds metabolic recovery temporarily during reperfusion but does not retard energy failure during global ischemia in rats. 相似文献
34.
Z Xu LE Reinstein G Yang S Pai G Gluckman PR Almond 《Canadian Metallurgical Quarterly》1997,24(11):1788-1792
The dose distribution from a 32P source has been measured and calculated in order to evaluate its application in endovascular irradiation. The source dimension was 27 mm in length and 0.3 mm in diameter and was embedded in the end of a Ni-Ti wire. Dose measurements were performed using radiochromic film in several specially designed tissue equivalent phantoms. Loevinger's point dose kernel was used for the calculation. The approximate dose rate at a radial distance of 1.5 mm from the center of the source was found to be 6.75 cGy/s per GBq (0.25 cGy/s per mCi), which allows the delivery of a therapeutic dose in a short time interval with a satisfactory homogeneity without stepping the source. However, the dose rate falls off almost exponentially along the radial distance. Therefore it may not be suitable for treating large diameter vessel from a centrally located source. The effect of a curved 32P wire source on the radial dose distribution was also investigated. The results showed that for a maximum bend of 180 degrees the dose rate was increased by as much as 20% along the inner radial distance but decreased by as much as 20% along the outer radial distance compared to the dose along a straight wire. However, for curvatures normally encountered in a clinical situation, the dose rate was changed less than 5%. 相似文献
35.
We report the case of a patient with advanced squamous carcinoma of the supraglottic larynx and hypopharynx who developed metastatic gastric deposits occurring at the site of a percutaneous endoscopic gastrostomy tube, inserted 10 months previously by the pull technique. We review seven previous reports of tumour deposits occurring at the site of placement of a percutaneous endoscopic gastrostomy in patients with head and neck cancer, and consider alternative methods of enteral feeding in such patients. 相似文献
36.
Hyponatremia is a common neuromedical problem seen in survivors of central nervous system injury. The etiology of this hyponatremia is often diagnosed as syndrome of inappropriate diuretic hormone (SIADH). Fluid restriction is usually the first line of treatment. However, this can exacerbate vasospasm and produce resultant ischemia. Cerebral salt wasting is a syndrome of renal sodium loss that may occur commonly after central nervous system injury, yet remains unrecognized. Treatment of cerebral salt wasting consists of hydration and salt replacement. This article uses a case report to discuss the importance of recognition of this syndrome, and treatment concerns are reviewed. 相似文献
37.
38.
J Xu E Mendez PR Caron C Lin MA Murcko MS Collett CM Rice 《Canadian Metallurgical Quarterly》1997,71(7):5312-5322
Members of the Flaviviridae encode a serine proteinase termed NS3 that is responsible for processing at several sites in the viral polyproteins. In this report, we show that the NS3 proteinase of the pestivirus bovine viral diarrhea virus (BVDV) (NADL strain) is required for processing at nonstructural (NS) protein sites 3/4A, 4A/4B, 4B/5A, and 5A/5B but not for cleavage at the junction between NS2 and NS3. Cleavage sites of the proteinase were determined by amino-terminal sequence analysis of the NS4A, NS4B, NS5A, and NS5B proteins. A conserved leucine residue is found at the P1 position of all four cleavage sites, followed by either serine (3/4A, 4B/5A, and 5A/5B sites) or alanine (4A/4B site) at the P1' position. Consistent with this cleavage site preference, a structural model of the pestivirus NS3 proteinase predicts a highly hydrophobic P1 specificity pocket. trans-Processing experiments implicate the 64-residue NS4A protein as an NS3 proteinase cofactor required for cleavage at the 4B/5A and 5A/5B sites. Finally, using a full-length functional BVDV cDNA clone, we demonstrate that a catalytically active NS3 serine proteinase is essential for pestivirus replication. 相似文献
39.
Gleason's score (GS) has been reported to be the most valuable prognostic factor in cases of prostate cancer. GS is solely dependent on the histological architecture of the prostate cancer, but, it seems doubtful that histological patterns are sufficient for evaluating the degree of malignancy of prostate cancer. We previously reported that the estimation of volume-weighted mean nuclear volume (MNV) might be a more useful prognosticator for prostate cancer than subjective histological grading. However, the previous study was conducted on patients treated in a single hospital, and the number of subjects was too small to draw a definitive conclusion. In this study, we analyzed a larger number of subjects at another institution using a blinded study design. A retrospective prognostic study of 195 patients with prostate cancer diagnosed between January 1966 and December 1988 at Kyoto University Hospital, and treated by conservative therapy, was conducted. Unbiased estimates of MNV were compared with the clinical stage and histological grading according to GS with regard to the prognostic value. Univariate analysis revealed that estimates of MNV, clinical stage, and GS all correlated significantly with disease-specific survival in cases of prostate cancer. Multivariate analysis of all cases also revealed that all of these factors were significant independent prognosticators of disease-specific survival. However, focusing on clinically localized cases (stages A, B, and C), multivariate analysis revealed that the estimation of MNV was the only powerful prognosticator of prostate cancer. This study indicates that the estimation of MNV is prognostically equal or superior to GS in cases of prostate cancer. We emphasized that the estimates of MNV is a more objective method for histological grading to predict the malignant potential of prostate cancer. 相似文献
40.
RJ Wilkinson K Hasl?v R Rappuoli F Giovannoni PR Narayanan CR Desai HM Vordermeier J Paulsen G Pasvol J Ivanyi M Singh 《Canadian Metallurgical Quarterly》1997,35(3):553-557
The diagnosis of infection caused by Mycobacterium tuberculosis is of increased public health concern following increases in the number of cases in developed countries and major increases in developing countries associated with the spread of human immunodeficiency virus (HIV) infection. The specificity of purified protein derivative skin testing for the detection of infection is compromised by exposure to environmental mycobacteria. Examination of sputum detects the most infectious patients, but not those with extrapulmonary disease. The 38-kDa antigen of M. tuberculosis contains two M. tuberculosis-specific B-cell epitopes. We overexpressed the gene for this antigen in Escherichia coli and evaluated the recombinant product in in vitro assays of T-cell function and as a target for the antibody response in humans. The sensitivity and specificity of the antigen as a skin test reagent were also assessed in outbred guinea pigs. We found that 69% of healthy sensitized humans recognize the antigen in vitro, as manifested by both cell proliferation and the production of gamma interferon. Untreated patients initially have a lower frequency of response (38%); this recovers to 72% during therapy. A total of 292 patients (20 with HIV coinfection) and 58 controls were examined for production of antibody to the 38-kDa antigen by using a commercially available kit. The sensitivity of the test in comparison with that of culture was 72.6%, and the specificity was 94.9%. The antigen was also tested for its ability to induce skin reactions in outbred guinea pigs sensitized by various mycobacterial species. The antigen provoked significant skin reactions in M. tuberculosis-, M. bovis BCG-, and M. intracellulare-sensitized animals. The significance of these findings and the usefulness of this antigen in immunodiagnosis are discussed. 相似文献