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101.
The potential of word processing for non-native student writers is explored through an examination of effects in the categories of writing process, quantity and quality of writing, planning and prewriting, revising, conception of writing, cognitive processing, setting effects, and attitudes. It is maintained that non-native writers may benefit in significant ways from the attributes of word processing and the conditions surrounding its use in composition instruction. Martha C. Pennington holds a Ph.D. in Linguistics from the University of Pennsylvania. As Reader in English at the City Polytechnic of Hong Kong, she directs research on the learning and teaching of English as a second language. Her most recent book is a collection edited with Vance Stevens entitled, Computers in Applied Linguistics(Multilingual Matters, 1992).  相似文献   
102.
Vinylidenebisphosphonic acid tetraethyl ester (1) and diazo ketones 7a-1 in ether at 22 degrees C yield pyrazoline bisphosphonate tetraethyl esters 8a-1 in moderate to good yield. These compounds were evaluated in animal models of arthritis: rat adjuvant-induced polyarthritis (AIP) and murine antigen-induced arthritis (AIA) and a murine model of chronic inflammation, the delayed type hypersensitivity granuloma reaction (DTH-GRA). (5-Benzoyl-2,4-dihydro-3H-pyrazol-3-ylidene)-bisphosphonic acid tetraethyl ester (8a), and [5-(3-fluorobenzoyl)-2,4-dihydro-3H-pyraxol-3-ylidene]- bisphosphonic acid tetraethyl ester (8d) significantly inhibited the arthritis models, AIP (15 mg/kg) and AIA (25 mg/kg), as well as the DTH-GRA (25 mg/kg). Conversion of 8a to the corresponding bisphosphonic acid, 10a, resulted in loss of activity. Compounds with alkyl substituents on the pyrazoline nitrogen, 9a-d, were inactive in the DTH-GRA. These results show that 8a and 8d have novel antiinflammatory activity and are capable of inhibiting chronic arthritis and inflammation in animals. Such compounds might be useful in man for treating chronic tissue injury associated with arthropathies such as inflammatory joint disease as well as other chronic inflammatory diseases.  相似文献   
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105.
Recent reports have demonstrated fusion of the TEL gene on 12p13 to the JAK2 gene on 9p24 in human leukemias. Three variants have been identified that fuse the TEL pointed (PNT) domain to (i) the JAK2 JH1-kinase domain, (ii) part of and (iii) all of the JH2 pseudokinase domain. We report that all of the human TEL/JAK2 variants, and a human/mouse chimeric hTEL/mJAK2(JH1) fusion gene, transform the interleukin-3 (IL-3)-dependent murine hematopoietic cell line Ba/F3 to IL-3-independent growth. Transformation requires both the TEL PNT domain and JAK2 kinase activity. Furthermore, all TEL/JAK2 variants strongly activated STAT 5 by phosphotyrosine Western blots and by electrophoretic mobility shift assays (EMSA). Mice (n = 40) transplanted with bone marrow infected with the MSCV retrovirus containing either the hTEL/mJAK2(JH1) fusion or its human counterpart developed a fatal mixed myeloproliferative and T-cell lymphoproliferative disorder with a latency of 2-10 weeks. In contrast, mice transplanted with a TEL/JAK2 mutant lacking the TEL PNT domain (n = 10) or a kinase-inactive TEL/JAK2(JH1) mutant (n = 10) did not develop the disease. We conclude that all human TEL/JAK2 fusion variants are oncoproteins in vitro that strongly activate STAT 5, and cause lethal myelo- and lymphoproliferative syndromes in murine bone marrow transplant models of leukemia.  相似文献   
106.
We conducted a study of the association between developmental reading disability (DRD) and immune disorders (ID) using both survey and immunoassay data in two separate samples of families. One sample was made up of twins and their parents and was ascertained through a population-based sampling scheme. The other sample was a set of extended pedigrees selected for apparent autosomal dominant transmission of DRD. We failed to find an association between DRD and ID in either sample, regardless of the method used to assess immune system function. Even though our twin sample provided evidence that both DRD and immune conditions were significantly heritable, there was no evidence for a genetic correlation between ID and DRD nor was there any clear indication that a special subgroup of individuals may be comorbid for these conditions because of genetic reasons. How these negative findings can be reconciled with the developmental hypothesis of Geschwind, Behan, Galaburda, and colleagues, and how they may relate to the gene locus influencing DRD that has been recently located in the HLA region of the short arm of chromosome 6 is discussed.  相似文献   
107.
Diabetic ulcers are the most common foot injuries leading to lower extremity amputation. Family physicians have a pivotal role in the prevention or early diagnosis of diabetic foot complications. Management of the diabetic foot requires a thorough knowledge of the major risk factors for amputation, frequent routine evaluation and meticulous preventive maintenance. The most common risk factors for ulcer formation include diabetic neuropathy, structural foot deformity and peripheral arterial occlusive disease. A careful physical examination, buttressed by monofilament testing for neuropathy and noninvasive testing for arterial insufficiency, can identify patients at risk for foot ulcers and appropriately classify patients who already have ulcers or other diabetic foot complications. Patient education regarding foot hygiene, nail care and proper footwear is crucial to reducing the risk of an injury that can lead to ulcer formation. Adherence to a systematic regimen of diagnosis and classification can improve communication between family physicians and diabetes subspecialists and facilitate appropriate treatment of complications. This team approach may ultimately lead to a reduction in lower extremity amputations related to diabetes.  相似文献   
108.
We have identified mutations in Raf-1 that increase binding to Ras. The mutations were identified making use of three mutant forms of Ras that have reduced Raf-1 binding (Winkler, D. G., Johnson, J. C., Cooper, J. A., and Vojtek, A. B. (1997) J. Biol. Chem. 272, 24402-24409). One mutation in Raf-1, N64L, suppresses the Ras mutant R41Q but not other Ras mutants, suggesting that this mutation structurally complements the Ras R41Q mutation. Missense substitutions of residues 143 and 144 in the Raf-1 cysteine-rich domain were isolated multiple times. These Raf-1 mutants, R143Q, R143W, and K144E, were general suppressors of three different Ras mutants and had increased interaction with non-mutant Ras. Each was slightly activated relative to wild-type Raf-1 in a transformation assay. In addition, two mutants, R143W and K144E, were active when tested for induction of germinal vesicle breakdown in Xenopus oocytes. Interestingly, all three cysteine-rich domain mutations reduced the ability of the Raf-1 N-terminal regulatory region to inhibit Xenopus oocyte germinal vesicle breakdown induced by the C-terminal catalytic region of Raf-1. We propose that a direct or indirect regulatory interaction between the N- and C-terminal regions of Raf-1 is reduced by the R143W, R143Q, and K144E mutations, thereby increasing access to the Ras-binding regions of Raf-1 and increasing Raf-1 activity.  相似文献   
109.
Eleven men and 50 women with severe hypothyroidism were studied. All patients had a serum PBI less than 3.0 mug/100 ml, 131I 24 hours uptake less than 13% and a a photomotogram contraction and half relaxation time of 380 msec or more. Before exercise the mean +/- SE heart rate was 68.39 +/- 3.26/min, the PR interval 17.08 +/- 0.37 csec, the QRS voltage (sum of the QRS amplitude in leads I, II and III) 16.44 +/- 0.89 mm (10mm = 1.0 mV) and the T wave amplitude 0.06 +/- 0.15 mm. A significant correlation (p less than 0.05) existed between the PBI values and the QRS voltage. Following exercise there was a significant acceleration of the heart rate (+ 23.39/min, p less than 0.001), shortening of the PR interval (-0.66 csec, p less than 0.02) and T wave elevation (+ 0.40 mm, p less than 0.001). ST segment changes were not observed in any case. Replacement treatment in 7 cases resulted in a significant change in the resting heart rate (+ 11.86/min. p less than 0.025), PR interval (-3.28 mm, p less than 0.025) and T wave height (+ 2.50 mm, p less than 0.01). These findings suggest that exercise may be used in the differentiation between hypothyroidism and coronary heart disease. The theoretical importance of these findings is also discussed. An increase in cardiac energy demands during exercise may be the cause for some of the ECG changes observed on exertion.  相似文献   
110.
This study explored the relationship of cognitively induced anxiety and hand temperature reduction in a nonclinical sample. Forty college students were randomly assigned to either the Anxiety Group or the Pleasant Group. Following a baseline period, individuals in the Anxiety Group discussed with the experimenter topics which were anxiety-producing for them. Individuals in the Pleasant Group discussed topics of a pleasant nature. During these discussions, hand temperatures were recorded from the palmar surface of the third finger on the dominant hand. Data analysis indicated that hand temperature decreases were significant only in subjects discussing anxiety-producing topics.  相似文献   
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