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排序方式: 共有529条查询结果,搜索用时 46 毫秒
41.
TF Davenport JR Albright JH Goldman SL Hagopian JE Lannutti KW Lai J LeBritton YC Lin AE Pifer HC Fenker DR Green GE Canough CC Chang TC Davis RW Joyner JA Poirier CH Georgiopoulos A Napier JM Marraffino JW Waters MS Webster EG Williams J Woosley JR Ficenec S Torres WP Trower 《Canadian Metallurgical Quarterly》1986,33(9):2519-2527
42.
RL Rodwell DI Tudehope P O'Regan R Minchinton AH Waters 《Canadian Metallurgical Quarterly》1991,1(1):63-67
Alloimmune neonatal neutropenia (ANN) is reported for the first time in two Australian aboriginals. Both infants displayed the typical clinical features of ANN with profound neutropenia which persisted for 7 weeks and only minor infectious episodes. However, management strategies differed for the two infants because in one case (complicated by uncertain paternity) serological confirmation of ANN was not obtained until after recovery of the infant's neutrophil count. The maternal antibodies could not be assigned to known neutrophil antigen specificities and a new antigen may be involved. The antibodies were reactive with > 99% of neutrophils in a Caucasian population. Aboriginals comprise 1% of the total population of Australia and 1-2% of the obstetric population at our institution. Thus, ANN may be an unrecognized disorder in this ethnic group and a possible cause of neonatal infection and mortality. 相似文献
43.
LS McCormick DM Black D Waters WV Brown B Pitt 《Canadian Metallurgical Quarterly》1997,80(9):1130-1133
This study describes the design, methodologic features, and baseline characteristics of an open-label randomized trial to determine whether aggressive lipid-lowering therapy with atorvastatin is an alternative to angioplasty or other catheter-based revascularization procedures in patients with significant coronary artery disease. Three-hundred forty-one patients with low-density lipoprotein (LDL) cholesterol > or = 115 mg/dl and > or = 1 defined narrowing of a major coronary artery were randomized to atorvastatin or the indicated catheter-based revascularization and conventional care (including lipid-lowering therapy if prescribed). Ischemic events are tracked for 18 months. The primary efficacy parameter is the incidence of an ischemic event, defined as 1 of the following: cardiovascular death, cardiac arrest, nonfatal myocardial infarction, the need for coronary bypass grafting or angioplasty, cerebrovascular accident, and worsening angina verified by objective evidence requiring hospitalization (including unstable angina). 相似文献
44.
Taxometric procedures such as mean above minus below a cut and maximum covariance can determine whether a trait is distributed as a discrete latent class. These methods have been used to infer taxonic structure in several personality and psychopathology constructs, often from analyses of rating scale data. This is problematic given (a) well established biases in ratings, (b) the human tendency to think categorically, and (c) implicit typological models of personality and psychopathology among expert raters. Using an experimental method in which the cognitive sets of raters were manipulated as dimensional versus categorical, it is demonstrated that pseudotaxonicity can be created readily with rating scale measures. This suggests that researchers avoid an exclusive reliance on rating scales when conducting taxometrics investigations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
Leventhal Adam M.; Waters Andrew J.; Boyd Susan; Moolchan Eric T.; Lerman Caryn; Pickworth Wallace B. 《Canadian Metallurgical Quarterly》2007,15(1):21
Gender differences in tobacco withdrawal are of considerable clinical importance, but research findings on this topic have been mixed. Methodological variation in samples sizes, experimental design, and measures across studies may explain the inconsistent results. The current study examined whether male (n = 101) and female (n = 102) smokers (≥15 cigarettes/day) differed in abstinence-induced changes on a battery of self-report measures (withdrawal, affect, craving), cognitive performance tasks (attention, psychomotor performance), and physiological responses (heart rate, blood pressure, brain electroencephalogram). Participants attended 2 counterbalanced laboratory sessions, 1 following 12 hr of abstinence and the other following ad libitum smoking. Results showed that women reported greater abstinence-induced increases in negative affect, withdrawal-related distress, and urge to smoke to relieve withdrawal distress. In contrast, both genders reported similar abstinence-induced changes in positive affect and urge to smoke for pleasure. Men and women exhibited generally similar abstinence-induced changes in physiological and cognitive performance measures. In addition, gender did not moderate the association between withdrawal symptoms and baseline measures of smoking behavior and dependence. Abstinence-induced changes in withdrawal distress mediated the effect of gender on latency until the 1st cigarette of the day at trend levels ( p 相似文献
46.
Weidong Xiang Waters D. Pratt T.G. Barry J. Walkenhorst B. 《Communications Magazine, IEEE》2004,42(12):88-95
A three-transmitter three-receiver orthogonal frequency-division multiplexing Bell Laboratories layered space-time testbed is set up, which achieves a peak data rate of 281.25 Mb/s and a spectral efficiency of 14.4 b/Hz/s. The transmitter of the testbed consists of three signal generators transmitting three independent OFDM signals at 25 Msamples/s synchronously. Three synchronized receiving links are used, each of which includes an RF receiver, an analog-to-digital converter, a digital downconverter, and a PowerPC processor for baseband processing. The performance and complexity of three typical BLAST detection techniques (linear detection, ordered decision feedback detection, and partial decision detection) are evaluated and compared using the data from the experiments conducted in both line-of-sight and non-line-of-sight indoor environments. 相似文献
47.
TCR-alpha-deficient mice spontaneously develop inflammatory bowel disease (IBD) at 8-9 mo old. This study characterizes an accelerated form of IBD induced by Cryptosporidium parvum infection. Cryptosporidium parvum-infected TCR-alpha-deficient mice developed IBD as early as 4 wk old when challenged at 1 wk old. The lesions of this accelerated IBD resembled the lesions of spontaneous IBD in TCR-alpha-deficient mice and consisted of a mononuclear cell infiltrate within the intestinal lamina propria and an increased proliferation of enterocytes. The mononuclear cells within the lamina propria consisted of B cells and gamma delta T cells. The distal ileum, cecum, and colon were grossly thickened due to a hyperplastic mucosa and edematous submucosa. The mechanism by which C. parvum infection accelerates development of IBD is presently unclear. 相似文献
48.
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50.
Covert fears, anxiety and depression in congenital heart disease 总被引:1,自引:0,他引:1
Our experience from attempts to identify bacteria isolated from boar bite/gore wounds is the background for a discussion of identification problems. Some organisms, although not very common or well-known, can be identified when using commercial kits or conventional methods, provided they are sufficiently characterized, as exemplified by Pasteurella aerogenes isolated from cases 1 and 2. Some organisms may be wrongly identified, or not identified, by both commercial kits and conventional methods, unless seen by experienced microbiologists with knowledge of the original literature. This is exemplified by case 3, in which the final identification result was Bisgaard's taxon 15. Sometimes isolates cannot be identified even in reference laboratories and by using available identification tables and databases. In such cases, the organism involved may turn out to belong to a previously undescribed taxon. This is illustrated by the strains isolated from cases 4 and 5. 相似文献