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排序方式: 共有471条查询结果,搜索用时 15 毫秒
41.
OBJECTIVE: To determine the behavioral, situational, and temporal effects of 4 months of methylphenidate (MPH) treatment for attention-deficit hyperactivity disorder (ADHD). METHOD: Ninety-one children with ADHD were randomly assigned to receive either MPH (titrated to a target dose of 0.7 mg/kg twice a day) or a placebo. Treatment effects were investigated with measures sensitive to various behaviors (core and associated symptoms), situations (home and school), time periods (morning and afternoon, after reaching the target dose, and after 4 months of treatment), and side effects. RESULTS: MPH treatment improved symptoms of ADHD and oppositional behavior at school, both in the morning and afternoon, but not at home. Side effects (increase in physiological and effective symptoms, lack of weight gain) were significantly more frequent with MPH than with placebo treatment. Benefit was evident after titration, but the onset of some side effects was delayed. Side effects were reported by parents but not by teachers. CONCLUSIONS: Positive effects of MPH on behavior are evident in the classroom, but with MPH given twice daily, parents do not report that MPH improves behavior at home. Greater impact on home behavior may require three times daily MPH and combined treatments. 相似文献
42.
Physiologically based indices of volumetric capnography in patients receiving mechanical ventilation
PV Romero U Lucangelo J Lopez Aguilar R Fernandez L Blanch 《Canadian Metallurgical Quarterly》1997,10(6):1309-1315
Several indices of ventilatory heterogeneity can be identified from the expiratory CO2 partial pressure or CO2 elimination versus volume curves. The aims of this study were: 1) to analyse several computerizable indices of volumetric capnography in order to detect ventilatory disturbances; and 2) to establish the relationship between those indices and respiratory system mechanics in subjects with normal lungs and in patients with acute respiratory distress syndrome (ARDS), both receiving mechanical ventilation. We studied six normal subjects and five patients with early ARDS mechanically ventilated at three levels of tidal volume (VT). Respiratory system mechanics were assessed by end-expiratory and end-inspiratory occlusion methods, respectively. We determined Phase III slopes, Fletcher's efficiency index, Bohr's dead space (VD,Bohr/VT), and the ratio of alveolar ejection volume to tidal volume (VAE/VT) from expiratory capnograms, as a function of expired volume. Differences between normal subjects and ARDS patients were significant both for capnographic and mechanical parameters. Changes in VT significantly altered capnographic indices in normal subjects, but failed to change ventilatory mechanics and VAE/VT in ARDS patients. After adjusting for breathing pattern, VAE/VT exhibited the best correlation with the mechanical parameters. In conclusion, volumetric capnography, and, specifically, the ratio of alveolar ejection volume to tidal volume allows evaluation and monitoring of ventilatory disturbances in patients with adult respiratory distress syndrome. 相似文献
43.
GW Brown PV Jallepalli BJ Huneycutt TJ Kelly 《Canadian Metallurgical Quarterly》1997,94(12):6142-6147
The fission yeast gene cdc18(+) is required for entry into S phase and for coupling mitosis to the successful completion of S phase. Cdc18 is a highly unstable protein that is expressed only once per cell cycle at the G1/S boundary. Overexpression of Cdc18 causes a mitotic delay and reinitiation of DNA replication, suggesting that the inactivation of Cdc18 plays a role in preventing rereplication within a given cell cycle. In this paper, we present evidence that Cdc18 is associated with active cyclin-dependent kinase in vivo. We have expressed Cdc18 as a glutathione S-transferase fusion in fission yeast and demonstrated that the fusion protein is functional in vivo. We find that the Cdc18 fusion protein copurifies with a kinase activity capable of phosphorylating histone H1 and Cdc18. The activity was identified by a variety of methods as the cyclin-dependent kinase containing the product of the cdc2(+) gene. The amino terminus of Cdc18 is required for association with cyclin-dependent kinase, but the association does not require the consensus cyclin-dependent kinase phosphorylation sites in this region. Additionally, both G1/S and mitotic forms of cyclin-dependent kinase phosphorylate and interact with Cdc18. These interactions between Cdc18 and cyclin-dependent kinases suggest mechanisms by which cyclin-dependent kinases could activate the initiation of DNA replication and could prevent rereplication. 相似文献
44.
PV Kumar 《Canadian Metallurgical Quarterly》1994,38(5):702-706
From 1980 to 1992, five cases of Askin tumor were diagnosed by fine needle aspiration cytology at the Shiraz University Hospitals, Namazi, Faghihi and Beheshti, Iran. All patients were female, their ages ranging between 15 and 22 years. Three of them had a mass on the right side and two on the left side of the chest. Chest roentgenography revealed no bone involvement. Two tumors involved the lungs and pleura. Urinary catecholamine levels were within normal limits. The fine needle aspiration smears revealed many small, round malignant cells with indistinct cytoplasm, a high nuclear/cytoplasmic ratio and prominent, multiple nucleoli. Homer-Wright rosettes were seen frequently. The cells were often arranged in rows simulating rouleaux formation. They were positively stained by periodic acid-Schiff stain. The histologic sections confirmed the cytologic diagnosis of Askin tumor. Four of the patients died within 7-11 months after treatment began. 相似文献
45.
CH Jagoe B Arnold-Hill GM Yanochko PV Winger IL Brisbin 《Canadian Metallurgical Quarterly》1998,213(1-3):255-262
Mercury methylation may be enhanced in wetlands and humic-rich, blackwater systems that crocodiles and alligators typically inhabit. Given their high trophic level and long life-spans, crocodilians could accumulate significant burdens of Hg. Our objectives were to survey Hg concentrations in alligators from several areas in the southeastern United States to test their utility as sentinels of Hg contamination, to examine relationships among Hg concentrations in various tissues and to look for any differences in tissue Hg concentrations among locations. We measured total Hg concentrations in alligators collected in the Florida Everglades (n = 18), the Okefenokee National Wildlife Refuge, Georgia (n = 9), the Savannah River Site (SRS), South Carolina (n = 49) and various locations in central Florida (n = 21), sampling tissues including blood, brain, liver, kidney, muscle, bone, fat, spleen, claws and dermal scutes. Alligators from the Everglades were mostly juvenile, but Hg concentrations in tissues were high (means: liver 41.0, kidney 36.4, muscle 5.6 mg Hg/kg dry wt.). Concentrations in alligators from other locations in Florida were lower (means: liver 14.6, kidney 12.6, muscle 1.8 mg Hg/kg dry wt.), although they tended to be larger adults. Alligators from the Okefenokee were smallest and had the lowest Hg concentrations (means: liver 4.3, kidney 4.8, muscle 0.8 mg Hg/kg dry wt.). SRS alligators had the greatest size range and intermediate Hg levels (means: liver 14.9, muscle 4.8 mg Hg/kg dry wt.). At some locations, alligator length was correlated with Hg concentrations in some internal organs. However, at three of the four locations, muscle Hg was not related to length. Tissue Hg concentrations were correlated at most locations however, claw or dermal scute Hg explained less than 74% of the variation of Hg in muscle or organs, suggesting readily-obtained tissues, such as scutes or claws, have limited value for non-destructive screening of Hg in alligator populations. 相似文献
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49.
AA Drosos PV Voulgari IA Papadopoulos EN Politi PE Georgiou AK Zikou 《Canadian Metallurgical Quarterly》1998,16(6):695-701
OBJECTIVE: To investigate the efficacy, tolerability and safety of cyclosporine A (CSA) in early rheumatoid arthritis (RA) patients. METHODS: Patients with an early diagnosis of RA, a disease duration of less than 3 years, and without prior disease modifying antirheumatic drug (DMARD) treatment were studied. They randomly received oral CSA (3 mg/kg/day) or oral methotrexate (MTX) (0.15 mg/kg/week). In addition, all patients in both groups received oral prednisone (7.5 mg/day). RESULTS: Fifty-two patients were assigned to the CSA group and 51 to the MTX group. After 24 months of treatment, 48 patients from the CSA group and 48 from the MTX group showed significant clinical improvement. This was evaluated by the duration of morning stiffness, grip strength, the total joint count, joint swelling, and joint tenderness and pain, compared to pre-treatment values. The clinical improvement was also associated with a significant decrease in ESR and CRP values in both groups. No significant radiological deterioration was observed in the CSA patients compared to those treated with MTX after 24 months. Four patients from the CSA group dropped out of the study, two because of a synovitis flare, one because of severe hypertrichosis and one because of severe gingival hyperplasia. Three patients from the MTX group withdrew, one because of disease flare-up and two because of gastrointestinal disturbances. CONCLUSION: Early immunointervention in RA patients appears to be crucial to limit the development of joint damage. Cyclosporine A appears to be effective, well tolerated and safe in the long-term treatment of RA and can therefore be used as a first immunomodulatory drug in the armamentarium for the treatment of RA. 相似文献
50.
BACKGROUND: The more common occurrence in women of cough due to angiotensin-converting enzyme inhibitors raises the possibility of gender-related differences in the sensitivity of the cough reflex. Of two recent studies that evaluated cough response to inhaled capsaicin in normal subjects, one demonstrated heightened sensitivity of the cough reflex in women compared with men, while the other revealed no gender-related differences. To further investigate this question, we reviewed our experience with cough challenge testing in normal volunteers. STUDY OBJECTIVE: To compare cough reflex sensitivity in healthy adult female and male subjects. DESIGN: Retrospective data analysis. SETTING: Academic medical center. PARTICIPANTS: One hundred healthy volunteers (50 male, 50 female). Interventions: Subjects inhaled capsaicin in ascending, doubling concentrations until the concentration inducing five or more coughs (C5) was reached. In addition, the concentration inducing two or more coughs (C2; cough threshold) was measured. Results: Mean log C5 was significantly lower in women than in men: 1.02+/-0.09 (SEM) microM vs 1.41+/-0.08 microM, respectively (p=0.002). Log C2 (cough threshold) was also significantly lower in female subjects: 0.534+/-0.068 microM vs 0.870+/-0.065 microM in male subjects (p=0.00058). CONCLUSION: Healthy women have a more sensitive cough reflex than do healthy men. The reasons for this significant gender difference remain to be elucidated, but may involve a heightened sensitivity, in women, of the sensory receptors within the respiratory tract that mediate cough. 相似文献