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91.
92.
Stephen Choi 《Canadian Medical Association journal》2004,170(1):70
93.
94.
Ultra-early evaluation of regional cerebral blood flow in severely head-injured patients using xenon-enhanced computerized tomography. 总被引:18,自引:0,他引:18
G J Bouma J P Muizelaar W A Stringer S C Choi P Fatouros H F Young 《Journal of neurosurgery》1992,77(3):360-368
The role of cerebral ischemia in the pathophysiology of traumatic brain injury is unclear. Cerebral blood flow (CBF) measurements with 133Xe have thus far revealed ischemia in a substantial number of patients only when performed between 4 and 12 hours postinjury. But these studies cannot be performed sooner after injury, they cannot be done in patients with intracranial hematomas still in place, and they cannot detect focal ischemia. Therefore, the authors performed CBF measurements in 35 comatose head-injured patients using stable xenon-enhanced computerized tomography (CT), simultaneously with the initial CT scan (at a mean (+/- standard error of the mean) interval of 3.1 +/- 2.1 hours after injury). Seven patients with diffuse cerebral swelling had significantly lower flows in all brain regions measured as compared to patients without swelling or with focal contusions; in four of the seven, cerebral ischemia (CBF less than or equal to 18 ml/100 gm.min-1) was present. Acute intracranial hematomas were associated with decreased CBF and regional ischemia in the ipsilateral hemisphere, but did not disproportionately impair brain-stem blood flow. Overall, global or regional ischemia was found in 11 patients (31.4%). There was no correlation between the presence of hypoxia or hypertension before resuscitation and the occurrence of ischemia, neither could ischemia be attributed to low pCO2. Ischemia was significantly associated with early mortality (p less than 0.02), whereas normal or high CBF values were not predictive of favorable short-term outcome. These data support the hypothesis that ischemia is an important secondary injury mechanism after traumatic brain injury, and that trauma may share pathophysiological mechanisms with stroke in a large number of cases; this may have important implications for the use of hyperventilation and antihypertensive drugs in the acute management of severely head-injured patients, and may lead to testing of drugs that are effective or have shown promise in the treatment of ischemic stroke. 相似文献
95.
Jonathan C. Craig Les M. Irwig James Christie Albert Lam Ella Onikul John F. Knight Premala Sureshkumar L. Paul Roy 《Pediatric nephrology (Berlin, Germany)》1997,11(4):455-459
Variability in the interpretation of micturating cystourethrography by paediatric radiologists for the diagnosis of vesicoureteric
reflux in children was evaluated. All 265 micturating cystourethrograms (MCUs) that were available from 304 consecutive children
aged 0.5 – 61 months – who were investigated after their first urine infection between 1993 and 1995 as part of a prospective
cohort study – were selected for interpretation. Three experienced paediatric radiologists from the same department independently
interpreted the MCUs according to the grading system of the International Reflux Study in Children, from grades 0 to V, with
the presence of intrarenal reflux also noted. Apart from being informed that urine infection was the indication for the MCU,
no other clinical information was given to the radiologists. The indices of variability used were the percentage of agreement
and the kappa statistic, expressed as a percentage. Both measures were weighted with integers representing the number of categories
from perfect agreement. Disagreement was analysed for children and kidneys. For the diagnosis of vesicoureteric reflux in
individual patients, including grade, the percentage of agreement was 96% – 97% (kappa 90% – 91%) and the weighted percentage
of agreement was 96% – 98% (weighted kappa 93% – 94%). The same high level of agreement was present for individual kidneys,
with a percentage of agreement of 97% – 98% (kappa 89% – 92%) and a weighted percentage of agreement of 98% – 99% (kappa 94% – 95%).
There was near perfect agreement in the interpretation of radiological micturating cystourethrography among three experienced
paediatric radiologists for the diagnosis and grade of vesicoureteric reflux. Any variations in the medical care of children
suspected of having vesicoureteric reflux are not explained by differences in the reporting of this diagnostic test.
Received June 19, 1996; received in revised form November 1, 1996; accepted December 6, 1996 相似文献
96.
The use of item banks and computerized adaptive testing (CAT) begins with clear definitions of important outcomes, and references those definitions to specific questions gathered into large and well-studied pools, or “banks” of items. Items can be selected from the bank to form customized short scales, or can be administered in a sequence and length determined by a computer programmed for precision and clinical relevance. Although far from perfect, such item banks can form a common definition and understanding of human symptoms and functional problems such as fatigue, pain, depression, mobility, social function, sensory function, and many other health concepts that we can only measure by asking people directly. The support of the National Institutes of Health (NIH), as witnessed by its cooperative agreement with measurement experts through the NIH Roadmap Initiative known as PROMIS (www.nihpromis.org), is a big step in that direction. Our approach to item banking and CAT is practical; as focused on application as it is on science or theory. From a practical perspective, we frequently must decide whether to re-write and retest an item, add more items to fill gaps (often at the ceiling of the measure), re-test a bank after some modifications, or split up a bank into units that are more unidimensional, yet less clinically relevant or complete. These decisions are not easy, and yet they are rarely unforgiving. We encourage people to build practical tools that are capable of producing multiple short form measures and CAT administrations from common banks, and to further our understanding of these banks with various clinical populations and ages, so that with time the scores that emerge from these many activities begin to have not only a common metric and range, but a shared meaning and understanding across users. In this paper, we provide an overview of item banking and CAT, discuss our approach to item banking and its byproducts, describe testing options, discuss an example of CAT for fatigue, and discuss models for long term sustainability of an entity such as PROMIS. Some barriers to success include limitations in the methods themselves, controversies and disagreements across approaches, and end-user reluctance to move away from the familiar. 相似文献
97.
98.
Eun-Jung Choi Byung-Duk Ahn Jae-Il Lee Jung-Wook Kim 《Journal of oral pathology & medicine》2007,36(4):250-251
We report a case of rare multiple internal resorptions. Etiology of multiple internal resorptions is unknown. Interestingly, the patient had an atopic dermatitis, which is possibly related to multiple and rapid internal resorptions. 相似文献
99.
Transforming growth factor-beta (TGF-beta) comprises a group of multifunctional regulatory proteins, whose effects include angiogenesis. The expression of TGF-beta 1 in gastric carcinomas (70 cases) has been determined and related to pathological features and microvessel count by immunohistochemical staining for TGF-beta 1 and Factor VIII related antigen. Prominent reactivity for TGF-beta 1 was associated with the depth of invasion (r = 0.2; p < 0.05) and increased microvessel count (r = 0.5; p < 0.05). Also, the microvessel count had a significant correlation with invasiveness (r = 0.34; p < 0.05) and lymph node metastasis (r = 0.28; p < 0.05). These findings indicate that TGF-beta 1 may have a role in tumor invasion and angiogenesis. 相似文献
100.