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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
971.
Louis Mendelson David Cook Mario Cruz-Rivera Sherahe Fitzpatrick Joseph A Smith 《The Journal of asthma》2002,39(3):227-237
A retrospective analysis, based on a randomized, placebo-controlled, 12-week study in children 6 months to 8 years of age with persistent asthma, was performed to compare the efficacy and safety of budesonide inhalation suspension 0.25 mg and 0.5 mg twice daily vs. placebo in children < 4 and > or = 4 years of age. Both age groups demonstrated significant (p < or = 0.050) improvement in nighttime and daytime asthma symptom scores and decreased bronchodilator use compared with placebo. In addition, the safety profile of twice-daily budesonide inhalation suspension was favorable in both age groups. 相似文献
972.
A L Forbes M J Arnaud C O Chichester J D Cook B N Harrison R F Hurrell S G Kahn E R Morris J T Tanner P Whittaker 《The American journal of clinical nutrition》1989,49(2):225-238
Relative bioavailability of two iron fortificants, electrolytic Fe and ferric orthophosphate, was related to that of the reference ferrous sulfate with in vitro and rat model depletion-repletion methods in four laboratories to compare values directly with those obtained in a parallel human study. In vitro testing was performed on Fe compounds with both solubility and dialysis in a simulated in vitro gastrointestinal digestion system. Two depletion-repletion techniques, hemoglobin-regeneration efficiency (HRE) and an official method of the Association of Official Analytical Chemists (AOAC), were examined. AOAC relative biological values (RBV) of electrolytic Fe were 0.66 and 0.78 and of FePO4 were 0.25 and 0.34. HRE values were 0.78 and 0.58 for electrolytic Fe and FePO4, respectively. When compared with FeSO4 in a radiolabeled farina-based meal fed to humans, the RBV of FePO4 was 0.25 and electrolytic Fe 0.75. Results obtained with the AOAC method serve as the most reliable prediction of Fe bioavailability in the human although in vitro dialysis is a promising screening technique. 相似文献
973.
As part of a general medical curriculum renewal, a new one-week course in diagnostic radiology was given to students at the beginning of their third year. The course format consisted of didactic presentations to the entire class, a single afternoon session of small group discussions of unknowns, and three daily case-of-the-day unknowns with prizes for correct responses. One hundred fifty-eight students were tested on the first and last days of the course; testing consisted of two parallel 46-item multiple choice questions given in a crossed design. Questions covered radiographic anatomy and pathology as well as proper test ordering. Differences in achievement before and after the course as measured by the pre- and post-tests were highly significant. The class achieved a mean of 27 (59%) correct responses on the pre-test and a mean of 37 (80%) on the post-test (F(1156) = 15.79; P less than .001). The reliability coefficient of the pre- and post-tests was about .30. A course critique was returned by 88 students. There was anticipated variation in the evaluations of the different didactic lecturers. Instructors receiving the highest scores were cited for their enthusiasm, clarity, and the relevance of their presentation. Conversely, those receiving low marks were cited as being unenthusiastic and boring, merely presenting example after example of radiographic abnormalities with little explanation. The afternoon small group discussions were perceived as the best part of the course. Despite the fact that moderator experience ranged from second year resident to full professor, the seminars received uniformly positive comments. 相似文献
974.
L J McGuigan D J Cook M E Yablonski 《Investigative ophthalmology & visual science》1986,27(12):1755-1757
A study was made in rabbits of the effect of topical dexamethasone ointment, .05%, and either subconjunctival or intraperitoneal D-penicillamine on the duration of function of glaucoma filtering surgery. The drugs were tested alone and in combination. Intraperitoneal D-penicillamine was not effective, either alone or combined with topical dexamethasone. Topical dexamethasone ointment alone and subconjunctival D-penicillamine alone significantly prolonged the duration of function of the filter surgery; however, when combined, no additional effect was observed. It was concluded that the institution of therapy with both drugs immediately after glaucoma filtering surgery was not the optimal temporal sequence for combining the two modes of therapy. 相似文献
975.
A femoroperoneal bypass using a cryopreserved human saphenous allograft was performed on a patient who presented with critical ischemia of the left lower extremity. The patient died of myocardial infarction 48 hours later and the graft was examined histologically. There was karryorhexis and focal neutrophilic infiltrate in the media underlying a layer of fibrin on the intimal surface. Immunoperoxidase studies showed nonspecific luminal deposition of immunoglobulins and fibrinogen. The histologic changes that occur in cryopreserved venous allografts are similar in experimental and human material and may be the result of anoxia of the vessel wall rather than immunologic mechanisms. 相似文献
976.
B Rosner N R Cook D A Evans M E Keough J O Taylor B F Polk C H Hennekens 《American journal of epidemiology》1987,126(6):1115-1125
A study of the variability of blood pressure was conducted among a total of 780 Massachusetts children, 335 children in East Boston and 445 children in Brookline, ages 8-18 years. All children had their blood pressure measured with a standard mercury sphygmomanometer in a school setting on four visits one week apart with three measurements per visit. In East Boston, repeat measurements were made for the same children for four consecutive years. A nested random effects model was used to estimate between- and within-visit variance components. For children aged 8-12 years, these were, respectively, 33.1, 12.0 in boys and 31.2, 11.1 in girls for systolic blood pressure and 57.7, 21.3 in boys and 56.6, 22.6 in girls for systolic muffling blood pressure (Korotkoff phase 4). For children aged 13-18 years of age, they were, respectively, 41.1, 11.8 in boys and 35.2, 12.2 in girls for blood pressure and 40.6, 15.5 in boys and 36.1, 11.4 in girls for diastolic blood pressure (Korotkoff phase 5). Within-person variability for systolic pressure was comparable to previously published data for 434 white adults ages 30-49 years not on antihypertensive medications; however, within-person variability for diastolic pressure was considerably higher in the children, accounting for over 75% of total variability among 8-12-year-old children, compared with 27% for adults. No meaningful effects of age, sex, or blood pressure level on variability of systolic pressure were found. However, age and level of blood pressure each had a large and independent inverse association with variability of diastolic pressure; variance components for younger children (ages 8-12 years) and children with low diastolic pressure (less than 60 mmHg) were approximately twice as large as for older children (ages 13-18 years) and children with diastolic pressure greater than or equal to 60 mmHg, respectively. Finally, predictive value estimates of blood pressure are provided for particular age-sex groups to enable one to efficiently identify children whose true mean level of blood pressure exceeds the 90th percentile for their age-sex group with minimum misclassification. Because of the substantial variability of diastolic pressure in young children, resulting in relatively low predictive value estimates, systolic pressure (either alone or in combination with diastolic pressure) may be more useful as the primary tool for screening children under age 13 years for high blood pressure. 相似文献
977.
At the present time, the cause of multiple sclerosis (MS) remains unknown, although it seem likely that one or more infectious agents triggers the disease, perhaps through an autoimmune mechanism. In this article, evidence linking the paramyxoviruses, canine distemper, and measles to MS is reviewed. 相似文献
978.
C M Heyworth J Hampson T M Dexter F Walker A W Burgess O Kan N Cook S J Vallance A D Whetton 《Growth factors (Chur, Switzerland)》1991,5(2):87-98
Interleukin-3 (IL-3) dependent multipotent haemopoietic stem cells FDCP-Mix A4 (A4) were induced to differentiate and develop into mature neutrophils in response to Granulocyte Macrophage Colony Stimulating Factor (GM-CSF) plus granulocyte CSF (G-CSF). This resulted in an increase in cell number over seven days of culture, following which the cells lost the ability to undergo further proliferation. The effect of GM-CSF on these cells has been assessed at various stages of development. Clonogenic cells, able to respond to GM-CSF, were generated only at days 3, 4 post-induction. From day 5 onwards, mature post-mitotic neutrophils are produced and clonogenic cells are lost. Loss of proliferative potential, in response to GM-CSF, was confirmed using [3H]-thymidine incorporation. Receptors for GM-CSF, were also measured during development using [125I]-GM-CSF binding assays. Although the dissociation constant for GM-CSF binding sites did not vary considerably, the number of such sites increased dramatically from about 20 (day 0, when the cells have a primitive morphology) to about 1000 by day 6 (when the cells are predominantly mature neutrophils). GM-CSF-stimulated Na+/H+ antiport activation was also determined. Although few GM-CSF receptors are expressed at day 0, there is a significant response (63% of maximal) to GM-CSF in terms of intracellular alkalinisation: this response increased markedly until, by day 4 (700 GM-CSF binding sites/cell), there is a maximal activation of the antiport by GM-CSF. By day 7 (greater than 900 GM-CSF binding sites/cell), however, there is significant reduction in activation of the Na+/H+ antiport by GM-CSF. Nonetheless, increased viability of these mature cells is still seen in response to GM-CSF. These results suggest that not only does expression of GM-CSF receptors alter during development of multipotential cells to mature neutrophils, but that these receptors are coupled to different intracellular effector mechanisms as the cells progressively mature. 相似文献
979.
Beverly Rene Hudson Chad Cook Adam Goode 《Journal of Manual and Manipulative Therapy》2008,16(2):82-88
Myelopathy is a form of neurological disease caused by compression of the spinal cord. Upper and lower quarter screens are commonly used in identifying myelopathy, although most of the screen components demonstrate poor or unstudied diagnostic value. The purpose of this case report is to describe the diagnostic process in detecting syringomyelia, an intramedullary lesion that may cause myelopathy. The patient was a 47-year-old female with a thoracic syrinx that was discovered by spinal magnetic resonance imaging (MRI) following a complicated and delayed clinical diagnostic course. Following surgical intervention and a two-week inpatient rehabilitation stay, the patient was discharged using a rolling walker for ambulation and was performing most transfers with modified independence. A complicating pattern of signs and symptoms combined with a diagnostic process guided by poorly studied screen components demonstrates the diagnostic dilemma associated with identifying the cause of myelopathy within the thoracic spine. This also indicates the need for further investigation of individual and clustered components of the neurological screen to improve the ability to identify patients in need of complete imaging studies in a more timely fashion. 相似文献
980.
Young rats were fed a niacin-deficient diet with and without 15 g/kg supplementary L-leucine. Both groups grew slowly for 5 wk and showed no difference in the severity of their condition. Nor did their 14CO2 production differ after intraperitoneal dosing with [methylene-14C]tryptophan. In a 2 X 3 X 3 multifactorial trial with a niacin-free basal diet, the effects of 15 g/kg supplementary leucine were compared with isonitrogenous glycine supplements. Half of the diets were also marginally deficient in pyridoxine and resulted in slower growth, but no interactive effect with leucine. The leucine supplement depressed excretion of N1-methylnicotinamide only in the groups receiving supplementary tryptophan. It was also associated with a depression in the level of nicotinamide nucleotides in the rats' livers that was not eliminated by addition of either 25 mg/kg nicotinic acid or 1 g/kg L-tryptophan. The existence of pellagra in Hyderabad, India, has been hypothesized to result from excessive leucine in the diet rather than from a deficiency of niacin/tryptophan. Neither our results with rats nor those of others appear to provide support for this hypothesis. 相似文献