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71.
Abstract Information and Communication Technologies (ICT) are now widespread in Australian schools but with variation in how, where, when and how much they are used. Computers may be located in a computer laboratory, distributed throughout the school, or students may use their own laptop computers. IT may be a subject in its own right or ICT may be used across all areas of the curriculum. It is how ICT is used in the school setting that is important in providing students with the skills to be participate in a 'knowledge society'. This paper examines the ways in which information and communication technologies influence teaching and learning in five Australian schools. Data were gathered through observation, interviews and document analysis in schools operating at the elementary and secondary grades in relatively technology rich environments. Each of the schools participated in the Australian component of the Second Information Technology in Education Study – Module 2 (SITES-M2) of innovative pedagogical practices. Several of the studies were of specific projects where ICT was the key enabler of the learning programme. Others focused on an entire school's approach to ICT as an agent for changed approaches to learning. 相似文献
72.
MH Safir AE Gousse ES Rovner DA Ginsberg S Raz 《Canadian Metallurgical Quarterly》1999,161(2):587-594
PURPOSE: The 4-defect repair of grade 4 cystocele corrects discrete and severe deficiencies of vesicourethral support. We describe this technique used during pelvic reconstruction in 130 women. MATERIALS AND METHODS: During a 3-year period 130 patients (age range 35 to 96 years) underwent repair of grade 4 cystocele using the 4-defect repair technique. Cystocele repair had been performed in 60 patients (46%) and hysterectomy had been performed in 85 (65%). A "goalpost incision" is used in the vaginal wall to facilitate separation of the wall from underlying perivesical fascia, entry into the retropubic space, and exposure of the urethropelvic ligament, cardinal ligament and perivesical fascia. The 4 polypropylene sutures are used to provide an anterior vaginal wall sling which is modified to incorporate perivesical fascia and cardinal ligaments. Central defect repair is achieved by approximation of the cardinal ligaments and midline plication of the perivesical fascia over absorbable mesh. RESULTS: A total of 112 patients were available for followup which ranged from 6 to 42 months (mean 21). Repair of grade 4 cystocele was accompanied by other transvaginal repairs in 94 patients (83%), including rectocele repair in 81, hysterectomy in 22 and enterocele repair in 31. Of the patients 92% had excellent objective and subjective results for anatomical cystocele repair. Of the patients with preoperative stress urinary incontinence 90% had excellent or good subjective results. De novo urge incontinence was seen in 7% of patients. CONCLUSIONS: The 4-defect repair technique relies on anatomical restoration of 4 distinct deficiencies of pelvic support and is highly effective for relief of symptoms of grade 4 cystocele. 相似文献
73.
SS Grigorian OG Baklavadzhian SM Minasian TsI Adamian ES Gevorkian SG Sarkisian 《Canadian Metallurgical Quarterly》1997,83(11-12):49-56
Effects of single, double, and rhythmic stimulation upon hypothalamic neurons responding to the 1st excitatory phase of lateral vestibular nucleus stimulation, were studied. The data obtained show that activation of some hypothalamic neurons following stimulation of the lateral vestibular nucleus has a monosynaptic character. The findings suggest that ascending afferents from the lateral vestibular nucleus to the hypothalamus pass via oligo- as well as polysynaptic pathways. 相似文献
74.
ES Harmelin RN Holcombe JP Goggin J Carbonell T Wellens 《Canadian Metallurgical Quarterly》1998,37(6):540-545
BACKGROUND: Ossification of the posterior longitudinal ligament (OPLL) may cause neuropathic bladder dysfunction due to spinal cord involvement. OPLL, unlike a traumatic spinal cord lesion, progresses insidiously and sometimes affects longer cord segments. As the manifestation of bladder dysfunction may depend on the development of OPLL, we studied the relationship between bladder function and roentgenographic changes in the spinal canals of OPLL patients. PATIENTS AND METHODS: Eighteen surgical candidates (11 males and 7 females, 34 to 85 years old) were studied urodynamically. Sixteen underwent CO2-filling cystometry, uroflowmetry and measurement of their residual urine volume. Cystometry was omitted in the remaining 2 patients. The vertical extent of OPLL and the degree of stenosis in the spinal canal was estimated by x-ray films and CT. RESULTS: The cystometric study revealed detrusor hyperreflexia in 2 patients and areflexic or underactive detrusors in 5 patients. Intermittent flows or considerable amounts of residual urine were also observed in the arefilexia/underactive group. Uroflowmetry showed a normal flow with little residual urine in both patients in whom cystometry was omitted. Bladder sensation was maintained in all patients. The occurrence of abnormal detrusor activity had no relationship to the degree of canal stenosis, while the occurrence of an areflexic or underactive detrusor correlated with the vertical extent of OPLL. CONCLUSION: Although detrusor hyperreflexia is common in an upper spinal cord lesion, attention should also be paid to the development of detrusor underactivity in patients with a wide vertical extent of OPLL. 相似文献
75.
76.
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78.
Salmon calcitonin (sCT) is an example of one of the many bioactive peptides that require amidation of the carboxy terminus for full potency. We describe a method for the production of amidated sCT in the mammary gland of transgenic rabbits. Expression of a fusion protein comprising human alpha lactalbumin joined by an enterokinase cleavable linker to sCT was directed to the mammary gland under the control of the ovine beta lactoglobulin promoter. C-terminal amidation in vivo was achieved by extending the sCT by a single glycine residue that provides a substrate for endogenous amidating activity in the mammary gland. Full characterization of the released sCT demonstrated it to be equivalent to synthetic standard in terms of structure, purity, and potency. 相似文献
79.
JW Andriko EP Kaldjian M Tsokos SL Abbondanzo ES Jaffe 《Canadian Metallurgical Quarterly》1998,22(9):1048-1058
Lymph nodes contain nonlymphoid accessory cells including follicular dendritic cells (FDCs), interdigitating dendritic cells (IDCs) and fibroblastic reticular cells (FBRCs). Neoplasms derived from FDCs are uncommon, and those of IDC origin are even more rare. We report the clinicopathologic features of 11 reticulum cell neoplasms, including 2 of FBRC origin. There were seven male patients and four female patients ranging in age from 13 to 73 years. All cases involved lymph nodes (cervical or supraclavicular-6 cases), (abdominal--2 cases), epitrochlear (1 case); two had more than one site of involvement (cervical lymph node and mediastinum--1 case, cervical and abdominal lymph nodes--1 case). One case of FDC tumor had concomitant Castleman's disease, plasma cell variant. Each neoplasm showed similar histology with oval-to-spindle-shaped cells in a storiform or fascicular pattern. Based on immunophenotypic findings, the neoplasms were classified as FDC (five cases), IDC (two cases), FBRC (three cases), and reticulum cell neoplasm, not otherwise specified (one case). The FDC tumors showed immunoreactivity for CD21 or CD35, vimentin, and CD68. The IDC tumors showed strong positivity for S-100 protein and variable positivity for CD68 and CD1a. The cases derived from FBRCs were positive for vimentin, desmin, and smooth-muscle actin. The neoplasm classified as reticulum cell neoplasm, not otherwise specified had similar morphologic features but showed only equivocal positivity for CD68 and vimentin. Follow-up was available for 9 of 11 (82%) cases with a mean of 3.5 years. Four of five patients with FDC tumors were alive with disease when last seen; the fifth is alive and well with no evidence of disease at 4-year follow-up. One patient with IDC tumor had a recurrence in a different nodal site. Two patients with FBRC tumor were disease free at follow-up of 2 years and 8 years, respectively. The patient with reticulum cell neoplasm, not otherwise specified, was alive and disease free 8 years after diagnosis. 相似文献
80.
T Self M Mahony J Fleming J Walsh SD Brown KP Steel 《Canadian Metallurgical Quarterly》1998,125(4):557-566
The mouse shaker-1 locus, Myo7a, encodes myosin VIIA and mutations in the orthologous gene in humans cause Usher syndrome type 1B or non-syndromic deafness. Myo7a is expressed very early in sensory hair cell development in the inner ear. We describe the effects of three mutations on cochlear hair cell development and function. In the Myo7a816SB and Myo7a6J mutants, stereocilia grow and form rows of graded heights as normal, but the bundles become progressively more disorganised. Most of these mutants show no gross electrophysiological responses, but some did show evidence of hair cell depolarisation despite the disorganisation of their bundles. In contrast, the original shaker-1 mutants, Myo7ash1, had normal early development of stereocilia bundles, but still showed abnormal cochlear responses. These findings suggest that myosin VIIA is required for normal stereocilia bundle organisation and has a role in the function of cochlear hair cells. 相似文献