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991.
JJ Dascanio GD Mechor YT Gr?hn DG Kenney CA Booker P Thompson CL Chiffelle JM Musser LD Warnick 《Canadian Metallurgical Quarterly》1995,56(9):1213-1218
A double-blinded randomized prospective clinical trial was designed to evaluate the effectiveness of flunixin meglumine and phenylbutazone for treatment of acute toxic mastitis in dairy cows. All cows were treated 4 times at 12-hour intervals by intramammary infusion of gentamicin (150 mg). A total of 45 dairy cows with toxic mastitis were randomly assigned to 1 of 3 treatment groups: group 1 (control), saline solution, IV; group 2, 1 g of flunixin meglumine, IV; or group 3, 4 g of phenylbutazone, IV. Physical examination and udder variables were assessed at initial examination and 24 hours later. Milk production was recorded at regular intervals from 1 week before until 10 weeks after development of mastitis. Rear quarters (34/45) were more commonly affected than front quarters. Thirty-five cows returned to the herd, 9 cows were culled, and 1 cow died. There were no significant differences among treatment groups in the need for further treatment or outcome. Klebsiella spp (18/45) and Escherichia coli (16/45) were the most common pathogens isolated by culture of milk from affected quarters. The overall bacteriologic cure rate on days 7 and 14 was 64 and 75%, respectively. At the time of initial examination, cows of the control group had higher rectal temperature than did cows of the flunixin group. At the examination 24 hours later, the rectal temperature of cows in all treatment groups was lower than the temperature at initial examination; at that time (24 hours), however, there were no significant differences in temperature among the treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
992.
Fetzer E. McMillin L.M. Tobin D. Aumann H.H. Gunson M.R. McMillan W.W. Hagan D.E. Hofstadter M.D. Yoe J. Whiteman D.N. Barnes J.E. Bennartz R. Vomel H. Walden V. Newchurch M. Minnett P.J. Atlas R. Schmidlin F. Olsen E.T. Goldberg M.D. Sisong Zhou HanJung Ding Smith W.L. Revercomb H. 《Geoscience and Remote Sensing, IEEE Transactions on》2003,41(2):418-431
The Atmospheric Infrared Sounder/Advanced Microwave Sounding Unit/Humidity Sounder for Brazil (AIRS/AMSU/HSB) instrument suite onboard Aqua observes infrared and microwave radiances twice daily over most of the planet. AIRS offers unprecedented radiometric accuracy and signal to noise throughout the thermal infrared. Observations from the combined suite of AIRS, AMSU, and HSB are processed into retrievals of atmospheric parameters such as temperature, water vapor, and trace gases under all but the cloudiest conditions. A more limited retrieval set based on the microwave radiances is obtained under heavy cloud cover. Before measurements and retrievals from AIRS/AMSU/HSB instruments can be fully utilized they must be compared with the best possible in situ and other ancillary "truth" observations. Validation is the process of estimating the measurement and retrieval uncertainties through comparison with a set of correlative data of known uncertainties. The ultimate goal of the validation effort is retrieved product uncertainties constrained to those of radiosondes: tropospheric rms uncertainties of 1.0 degC over a 1-km layer for temperature, and 10% over 2-km layers for water vapor. This paper describes the data sources and approaches to be used for validation of the AIRS/AMSU/HSB instrument suite, including validation of the forward models necessary for calculating observed radiances, validation of the observed radiances themselves, and validation of products retrieved from the observed radiances. Constraint of the AIRS product uncertainties to within the claimed specification of 1 K/1 km over well-instrumented regions is feasible within 12 months of launch, but global validation of all AIRS/AMSU/HSB products may require considerably more time due to the novelty and complexity of this dataset and the sparsity of some types of correlative observations. 相似文献
993.
Ultrafine grains were developed in Hadfield manganese steels through appropriate thermomechanical processing. The steels contained from 1.2 to 1.7 wt.% C and 12.3–16.3 wt.% Mn. The austenite grains. 2–8 μm in size, were stabilized against grain growth by a dispersion of fine carbides, typically less than 1 μm. The processed materials were evaluated for superplastic properties at elevated temperatures (750–900 °C). Values for the strain rate sensitivity exponent m in the expression
ranged from 0.37 to 0.65. The value of m in the superplastic regime was found to depend on composition, grain size and temperature. At 23 °C, the fine-grain steels showed higher yield strengths and hardness values, but lower ductility, relative to values reported for commercially processed materials. 相似文献
994.
995.
996.
Ankle osteoarthritis scale 总被引:1,自引:0,他引:1
Although there is a wide array of outcome tools for assessing patients with symptomatic ankle arthritis, no disease-specific instrument for ankle arthritis has been shown to be reliable and valid. The purpose of this study was to develop a simple, reliable, and validated outcome measure for the clinical assessment of ankle osteoarthritis. We modified the Foot Function Index, a visual analog-based scale used to assess rheumatoid foot problems, to measure patient symptoms and functional limitations stemming from osteoarthritis of the ankle joint. Test-retest reliability and criterion and construct validity were determined for the overall Ankle Osteoarthritis Scale and its two subscales (pain and disability). Overall reliability (r=0.97; 95% confidence interval [CI], 0.94-0.99), pain subscale reliability (r=0.95; 95% CI, 0.90-0.98), and disability subscale reliability (r=0.94; 95% CI, 0.88-0.97) were excellent. Criterion validity testing of the instrument with the WOMAC (a disease-specific scale for osteoarthritis) and the SF-36 (a general health survey) showed a high degree of concordance for related subscales. Construct validity using a physical measure of ankle function demonstrated sensitivity of the instrument to the degree of joint dysfunction. Normative data were obtained from 562 individuals who were not patients (264 men and 298 women). The responses were analyzed for trends in gender, body mass index, presence of arthritis, history of fracture in relation to the response levels, and age. A small but statistically significant main effect for gender was found, with women consistently reporting higher pain, disability, and total index scores. Body mass index and arthritis were also found to correlate with response answers across the subscale and total index scores; however, these factors only accounted for 12% of the variation. The Ankle Osteoarthritis Scale is a reliable and valid self-assessment instrument that specifically measures patient symptoms and disabilities related to ankle arthritis. 相似文献
997.
CL Loprinzi TM Pisansky R Fonseca JA Sloan KM Zahasky SK Quella PJ Novotny TA Rummans DA Dumesic EA Perez 《Canadian Metallurgical Quarterly》1998,16(7):2377-2381
PURPOSE: Hot flashes can be a prominent clinical problem for breast cancer survivors and men who undergo androgen-deprivation therapy. Anecdotal information suggested a low dose of a relatively new antidepressant, venlafaxine, could abrogate this clinical problem. MATERIALS AND METHODS: This study included 28 consecutive assessable patients entered onto a phase II clinical trial. Hot flash data were collected by daily diary questionnaires during a 1-week baseline period and then for 4 weeks, during which time patients received venlafaxine 12.5 mg orally twice daily. RESULTS: Fifty-eight percent of patients who completed the study had a greater than 50% reduction in hot flash scores (frequency times severity) during the fourth treatment week as compared with the baseline week. Median weekly hot flash scores were reduced by 55% from baseline during the fourth week of venlafaxine therapy. Therapy was generally well tolerated and appeared to alleviate fatigue, sweating, and trouble sleeping. CONCLUSION: Venlafoxine appears to represent an efficacious new method to alleviate hot flashes. Further evaluation of this compound for alleviating hot flashes is indicated. 相似文献
998.
This paper focuses on a subset of homosexual boys whose mixed gender experience moves beyond the conventional categories of masculinity and femininity, and who are often labeled as pathological due to a reluctance to recognize the reality of gender variance and cross-gendered identifications within the domain of mental health. Clinical examples are offered to highlight the need for a theory of gender that accounts for the interweaving of gender and psychic structure as they co-evolve and reflect the chaos inherent in human subjectivity. 相似文献
999.
1000.
MP Heyes K Saito A Lackner CA Wiley CL Achim SP Markey 《Canadian Metallurgical Quarterly》1998,12(10):881-896
This study investigated the sources of quinolinic acid, a neurotoxic tryptophan-kynurenine pathway metabolite, in the brain and blood of HIV-infected patients and retrovirus-infected macaques. In brain, quinolinic acid concentrations in HIV-infected patients were elevated by > 300-fold to concentrations that exceeded cerebrospinal fluid (CSF) by 8.9-fold. There were no significant correlations between elevated serum quinolinic acid levels with those in CSF and brain parenchyma. Because nonretrovirus-induced encephalitis confounds the interpretation of human postmortem data, rhesus macaques infected with retrovirus were used to examine the mechanisms of increased quinolinic acid accumulations and determine the relationships of quinolinic acid to encephalitits and systemic responses. The largest kynurenine pathway responses in brain were associated with encephalitis and were independent of systemic responses. CSF quinolinic acid levels were also elevated in all infected macaques, but particularly those with retrovirus-induced encephalitis. In contrast to the brain changes, there was no difference in any systemic measure between macaques with encephalitis vs. those without. Direct measures of the amount of quinolinic acid in brain derived from blood in a macaque with encephalitis showed that almost all quinolinic acid (>98%) was synthesized locally within the brain. These results demonstrate a role for induction of indoleamine-2,3dioxygenase in accelerating the local formation of quinolinic acid within the brain tissue, particularly in areas of encephalitis, rather than entry of quinolinic acid into the brain from the meninges or blood. Strategies to reduce QUIN production, targeted at intracerebral sites, are potential approaches to therapy. 相似文献