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1.
Quality of life in stroke survivor–caregiver dyads: a new conceptual framework and longitudinal study protocol 下载免费PDF全文
2.
3.
Intracranial circulation: pulse-sequence considerations in three- dimensional (volume) MR angiography 总被引:2,自引:0,他引:2
The technique and feasibility of magnetic resonance (MR) angiography of intracranial vessels were studied in 35 healthy volunteers. Variations in image orientation, repetition time (TR), and flip angle were evaluated to determine their effects on flow-related enhancement. Gradient modifications--including echo time (TE), motion compensation, bandwidth, and field of view--were also studied in an effort to reduce motion-induced phase shifts. Results indicated that a FISP (fast imaging with steady precession) sequence with a TR of 50 msec, TE of 15 msec, velocity compensation in the read and section-select directions, acceleration compensation in the read direction, anisotropic volume, and a 1.25-mm partition thickness produced three-dimensional angiographic MR images that were accurate and reproducible in the depiction of the major intracranial vessels. Difficulties with field of view, persistent signal void secondary to higher-order motion, and spatial resolution remain major problems requiring additional study. 相似文献
4.
B E Buck L Resnick S M Shah T I Malinin 《Clinical orthopaedics and related research》1990,(251):249-253
This study demonstrates by a virologic culture method that human immunodeficiency virus (HIV) resides in bone. After freezing, some initially positive specimens no longer yielded virus, but those that continued to yield virus were not further altered by subsequent washing, which removed essentially all marrow, or by freeze-drying. The safeguards against potential transmission of HIV by a bone allograft are principally the screening and testing methods previously described, although there may be a further reduction of the remote residual risk by the freezing step in the usual technical sequence for tissue banking by sterile techniques. 相似文献
5.
Maxillary sinusitis in adults: an evaluation of placebo-controlled double-blind trials 总被引:1,自引:0,他引:1
BACKGROUND: In general practice, acute sinusitis is frequently diagnosed
and treated with antibiotics. OBJECTIVE: This study aimed to determine the
evidence for the effectiveness of antibiotic treatment in acute maxillary
sinusitis in adults by assessing the methodological quality of
placebo-controlled double-blind randomized trials. METHOD: An evaluation by
four raters through a 35-item scoring-scale for internal and external
validity of all placebo-controlled double-blind randomized trials on acute
sinusitis found between January 1966 and July 1996. RESULTS: Eighty-five
trials were excluded because they were not placebo-controlled,
double-blind, randomized, or were carried out in patients with chronic
sinusitis or in children. The three remaining trials were performed in
different populations (one in general practice) between 1973 and 1978. Only
one study claimed superiority of antibiotic treatment. Different inclusion
criteria and major outcome measures were used by the authors. The
reliability of major outcome events was reported poorly or not at all and
in two studies outcome measures were clinically inappropriate. The studies
scored 30-62% of the maximum attainable score for internal validity and
10-20% for external validity. CONCLUSION: The effectiveness of antibiotic
treatment in acute maxillary sinusitis in a general practice population is
not based sufficiently on evidence.
相似文献
6.
Thirty-five abdominal computed tomographic (CT) scans of 27 patients with peritoneal metastases from a mucin-producing tumor of the appendix, colon, small bowel, or ovary were retrospectively reviewed. Fifteen scans were obtained of 15 patients after CT with intraperitoneal infusion of contrast material (IP), and 20 scans were obtained of 16 patients with CT without IP. Subsequent exploratory laparotomy revealed that all 27 patients had multi-focal spread of peritoneal metastases. The sensitivity of CTIP and CT without IP for detection of peritoneal metastases at all sites of involvement was 61% and 59%, respectively. For CTIP, the highest sensitivity was in the right subphrenic space (88%), splenic hilum (86%), and left subphrenic space (83%). For CT without IP, the highest sensitivity was noted in the splenic hilum (100%), left subphrenic space (75%), and left paracolic gutter (75%). CTIP and CT without IP had low sensitivity for detection of disease in the greater omentum (50% each) and small-bowel mesentery (38% and 59%, respectively), two areas that had the highest frequency of metastases. 相似文献
7.
Anne Rannard Deborah Buck David E J Jones Oliver F W James Ann Jacoby 《Clinical gastroenterology and hepatology》2004,2(2):164-174
BACKGROUND AND AIMS: Assessment of health-related quality of life (HRQOL) is not routinely reported in the literature on chronic liver disease (CLD). Few studies have examined quality of life (QOL) in patients with primary biliary cirrhosis (PBC) despite its significant functional impact. One of the reasons for the lack of HRQOL measurement in patients with PBC may be the absence of a well-recognized and widely used measure that clinicians can use in ordinary clinical practice. The aim of this study is to evaluate HRQOL measures used in patients with PBC and examine the suitability of the measures for these patients. METHODS: A literature search identified reports that focused on any aspect of QOL in patients with PBC. Key texts were identified containing generic, domain-specific, and condition-specific measures. The identified measures were systematically evaluated for appropriateness, acceptability, reliability, validity, precision, and responsiveness. RESULTS: Twenty measures were identified from 9 key texts. Six of the measures were previously validated generic measures; 10 were domain-specific measures previously used to measure fatigue, depression, and psychological distress in general and psychiatric populations; and 4 measures had been developed in patients with CLD. Reporting of reliability and validity generally was consistent for all measures used. However, reporting of the remaining criteria was variable, particularly in relation to responsiveness over time and acceptability of the measures to patients with PBC. CONCLUSIONS: A clearer and more rigorous approach is needed in reporting the properties of HRQOL measures used in patients with PBC to help clinicians decide which measures are most suitable for these patients. 相似文献
8.
This study investigated the use of attentional control strategies in the self-management of pain using daily process design methodology. Twenty six cancer patients with pain completed diaries 3 times daily for 10 days. Diaries incorporated measures of pain intensity, affect, coping, coping efficacy, and the novelty and predictability of pain, and participants completed a cross-sectional measure of catastrophizing. At the across-person level, focusing on pain was associated with increased negative affect, and the use of pain focusing strategies was positively correlated with experiencing pain that was novel in its location or quality. Distractions that were interesting, important and pleasant were positively correlated with positive affect, perceptions of control over pain and ability to decrease pain. Over-prediction of pain was positively correlated with catastrophizing, and negatively correlated with perceptions of control over and ability to decrease pain. The within-person analysis (ARIMA modelling) showed that catastrophizing moderated the effects of pain focusing strategies, novel pain and over-predictions of pain. Meta-analysis of the ARIMA models revealed that the within-person effects of using attentional strategies did not generalize across the sample. These findings indicated that the effects of distraction strategies are influenced by their motivational-affective significance rather than the frequency with which they are used, and provided further evidence that the threat value of pain influences the way in which people cope with their pain. Theoretical and clinical implications are discussed. 相似文献
9.
J H Imatani S H Miller D C Buck R J Demuth P F Parshley 《Annals of plastic surgery》1986,16(2):116-120
Rats subjected to a standard electrical burn of 250 volts for 10 seconds receive a severe injury stimulating a pronounced systemic circulatory response. Initial postinjury hyperemia is replaced by a low perfusion state within 24 hours. Our study demonstrates the difficulty in isolating regional microcirculatory alterations under such circumstances. Modification of the burn model or the method of fluid resuscitation may minimize the influence of this dynamic systemic response. 相似文献
10.
The enterohepatic circulation of T-2 toxin and its conjugated metabolites was examined in bile duct-cannulated male rats. Rats administered tritiated T-2 toxin intraduodenally (id) eliminated 44.65% and 57.25% of the administered dose in the bile within 4 and 8 hr post-dosing, respectively. TLC profiles of the T-2 metabolites were similar after intravascular and id administration. The major metabolites detected were 3'-OH-hydroxytryptamine-2 (HT-2), glucuronic acid conjugates, T-2 tetraol (TOL), 4-deacetylneosolaniol (4-DN), and HT-2. Tritium-labeled glucuronides obtained from the bile of rats administered [3H]T-2 toxin intravascularly were extracted and purified using C-18 and silica column chromatography. Enzymatic hydrolysis followed by TLC and GC/MS indicated that the aglycone portion of the glucuronides were composed of 3'-OH HT-2, HT-2, 4-DN, and TOL. After id administration of the glucuronides the rats eliminated 6.01% (4 hr) and 11.86% (8 hr) of the dose in the bile. No free metabolites of T-2 toxin were detected in the bile of any animals administered the purified glucuronides. Oral treatment of the rats with the beta-glucuronidase inhibitor, saccharolactone, did not produce a significant decline in the amount of radioactivity recovered in the bile following administration of the tritium-labeled glucuronides. These studies substantiate the enterohepatic circulation of T-2 toxin metabolites. 相似文献