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61.
62.
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
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64.
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
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66.
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
67.
A 12-year-old girl with a history of fast myopia progression underwent advanced orthokeratology (ortho-k) treatment and suffered from recurrent lens binding and central corneal staining. The problem could not be fixed by lens fenestration and refitting with a less aggressive lens (three-zone ortho-k) design. After refitting with a lower target advanced ortho-k lens, these complications were no longer occurring, and the amount of power reduction was greater than expected considering the target designed for the refitted lenses. During the following 15 months of ortho-k lens wear, there was no clinically significant change to her refractive error. The patient and her parents were happy with the outcome, although the refractive error was not totally eliminated and she still needed to wear spectacles for clear vision. Possible etiologies of the complications are discussed. 相似文献
68.
W. Y. Zhang Research Fellow A. Li Wan Po Professor 《BJOG : an international journal of obstetrics and gynaecology》1998,105(7):780-789
Objective To quantify the efficacy and safety of naproxen, ibuprofen, mefenamic acid, aspirin and acetaminophen (paracetamol) in the treatment of primary dysmenorrhoea through a systemic overview of randomised controlled trials.
Methods MEDLINE, EMBASE and the Science Citation Index were searched for randomised controlled trials. Efficacy was assessed by measurement of pain relief, requirement for rescue analgesics, restriction of daily life and absence from work or school. The rate ratios of side effects were used to assess safety.
Results Fifty-six trials describing 55 comparisons of analgesics with placebo and 12 direct comparisons with other analgesics met our inclusion criteria. Women taking naproxen were over three times more likely to have at least moderate pain relief than those taking placebo. Ibuprofen, mefenamic acid and aspirin were also superior to placebo but acetaminophen was not. The requirement for rescue analgesics, restriction of daily life and absence from work or school were less frequent with naproxen and ibuprofen than placebo but not with aspirin or acetaminophen. Direct comparisons did not show any difference between naproxen and ibuprofen. Side effects occurred more frequently only with naproxen when compared with placebo.
Conclusion Naproxen, ibuprofen, mefenamic acid and aspirin are all effective in primary dysmenorrhoea. Ibuprofen appears to have the most favourable risk-benefit ratio. Acetaminophen appears to be less effective than nonsteroidal anti-inflammatory drugs, but there was only one trial meeting our inclusion criteria and further studies are required. 相似文献
Methods MEDLINE, EMBASE and the Science Citation Index were searched for randomised controlled trials. Efficacy was assessed by measurement of pain relief, requirement for rescue analgesics, restriction of daily life and absence from work or school. The rate ratios of side effects were used to assess safety.
Results Fifty-six trials describing 55 comparisons of analgesics with placebo and 12 direct comparisons with other analgesics met our inclusion criteria. Women taking naproxen were over three times more likely to have at least moderate pain relief than those taking placebo. Ibuprofen, mefenamic acid and aspirin were also superior to placebo but acetaminophen was not. The requirement for rescue analgesics, restriction of daily life and absence from work or school were less frequent with naproxen and ibuprofen than placebo but not with aspirin or acetaminophen. Direct comparisons did not show any difference between naproxen and ibuprofen. Side effects occurred more frequently only with naproxen when compared with placebo.
Conclusion Naproxen, ibuprofen, mefenamic acid and aspirin are all effective in primary dysmenorrhoea. Ibuprofen appears to have the most favourable risk-benefit ratio. Acetaminophen appears to be less effective than nonsteroidal anti-inflammatory drugs, but there was only one trial meeting our inclusion criteria and further studies are required. 相似文献
69.
70.
Jae Sue Choi Han Suk Young Jong Cheol Park Jin-Ho Choi Won Sick Woo 《Archives of pharmacal research》1986,9(4):233-236
The flavonoids isolated from the leaves ofRhododendron brachycarpum, were identified as quercetin, avicularin, quercitrin and hyperin. 相似文献