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1.
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding.  相似文献   
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Clinical outcomes data can be used to facilitate patient management decisions, assess clinician and organizational performance, and to provide evidence for the effectiveness of surgery and rehabilitation. The validity of the inferences made from outcomes data are dependent on the validity of the outcomes measures themselves and the circumstances under which the data were collected, analyzed, and interpreted. Clinical outcomes may include measures of impairment of body structure and function, activity limitation, and participation restriction. However, because the relationship between impairment and the resulting activity limitation and participation restriction is not direct, and because activity limitations and participation restrictions are of the utmost concern to the athlete, the primary clinical outcome should be measures of activity limitation and participation restriction. Activity limitation and participation restriction may be measured either through direct observation of performance or by general or specific measures of health related quality of life. Clinical outcomes data must be collected systematically to ensure valid inferences from the data.  相似文献   
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39 human immunodeficiency-virus-1 (HIV-1)-positive hemophiliacs who had been regularly treated with non-virus-inactivated intermediate-purity factor VIII concentrates were divided into two groups. Group A consisted of 21 patients with a CD4/CD8 cell ratio of less than 1.0 and group B of 18 patients with a CD4/CD8 cell ratio of greater than 1.0. All patients of group A were switched to a high-purity virus-inactivated factor VIII concentrate, whereas patients of group B continued to receive the intermediate-purity concentrate. There was no significant difference in the average decline of CD4 cells between the two groups during the observation period. 9 patients of group A and 4 patients of group B developed AIDS. 5 patients of group A but 11 patients of group B remained clinically asymptomatic. We conclude that the 15-fold increase in purity of the factor VIII concentrate had no apparent beneficial effect on the CD4 cell counts in this patient group.  相似文献   
5.
OBJECTIVES: The introduction of 48-hour wireless pH testing offers clinicians a new alternative for the objective documentation of reflux. The success of transnasal wireless pH capsule placement has not been previously described. The purpose of this investigation was to describe our experience with transnasal wireless pH capsule placement. METHODOLOGY: All patients undergoing unsedated transnasal esophagoscopy and wireless pH capsule placement between January 1, 2003 and July 31, 2003 were prospectively evaluated. Data concerning patient tolerance, success of capsule placement and function, complications, and pH recordings were collected. RESULTS: During this time, 46 persons were evaluated. The mean age of the cohort was 52 years. Of the patients, 50% were male. The indications for the procedure were chronic cough (18/46), gastroesophageal reflux disease (18/46), and larygopharyngeal reflux (10). Of the procedures performed, 85% (39/46) were successful. Complications included epistaxis (2/46), laryngospasm (2/46), and vasovagal reaction (1/46). CONCLUSIONS: The transnasal placement of a wireless pH capsule is a safe and effective diagnostic adjunct to unsedated transnasal esophagoscopy.  相似文献   
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Although anxiety is a well-established obstacle to the delivery of effective health care, there have been no attempts to measure it in the optometric consulting room. In this paper, we introduce physiological and psychological techniques that may be used to evaluate anxiety and arousal in the consulting room and present data from a small group of patients attending for a routine eye examination. Specifically, arousal was assessed before, during, and after the examination by measuring skin conductance in five patients. Anxiety was evaluated using the State-Trait Anxiety Inventory. Our data confirm the ability of these techniques to quantify arousal and anxiety in the optometric consulting room and reveal a previously unknown but important facet of the eye examination. We conclude that these techniques are suitable for use in further experimental work and may be used to identify factors capable of reducing anxiety in the optometric consulting room.  相似文献   
8.
Utilization of three milk diets including cream, casein or whey, each naturally labelled with 13C (1 mmol 13C excess) from C4 sources, by six young male calves of the Deutsche Fleckvieh breed was investigated in a Latin-square split-plot design. Each milk diet was examined under resting conditions and during a short period of physical exercise on a treadmill. Delta 13C values (/1000) in carbon dioxide in expired air were measured at intervals of about 1 h during 6.5 h after food intake. Expired air samples for CO2 isolation, subsequent isotopic analysis, measurement of CO2 production and respiratory quotient were taken at about hourly intervals and 13C recovery rates over 6.5 h were calculated. Feeding milk containing enriched milk casein, cream, or whey resulted in maximal significant 13C enrichments over background (delta 13C) in CO2 of +1, +2.4 and +2.2 /1000, and recovery rates of 3.6, 9.9 and 12.2% respectively. This comparison shows the different kinetic behaviour of the main nutrients during the oxidation in tissues. The short exercise period (5 min at 1 J/s per kg body-weight +5 min at 2 J/s per kg body-weight) did not influence the recovery rates significantly. However, after 10 min of muscular exercise there was a brief decrease in delta 13C value of expired air which disappeared within the first 5 min of rest. These experiments demonstrate for the first time the applicability of the 13C breath test with naturally enriched diets in animal nutrition research and that quantitative results may be obtained.  相似文献   
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In-vitro maturation (IVM) of oocytes is a promising technique to reduce the costs and avert the side-effects of gonadotrophin stimulation for in-vitro fertilization (IVF). The pregnancy rates from oocytes matured in vitro are much lower than those of in-vivo stimulation cycles indicating that optimization of IVM remains a challenge. Therefore, we investigated the effect of supplementation of the medium with gonadotrophins, oestradiol and epidermal growth factor (EGF) and the effect of retaining or removing the cumulus cells on nuclear and cytoplasmic maturation of immature oocytes. Human germinal vesicle (GV) oocytes obtained after gonadotrophin stimulation for intracytoplasmic sperm injection (ICSI) were cultured in a complex defined medium either supplemented with gonadotrophins, oestradiol and physiological concentrations of EGF (2 ng/ml) or gonadotrophins and oestradiol alone. The cumulus cells were either removed or kept intact. In GV stage oocytes cultured without cumulus (group I) significantly more oocytes reached the metaphase II (MII) stage at 30 h in media supplemented with EGF (64.3 versus 33.9%, P < 0.003). For oocytes cultured with intact cumulus (group II), more oocytes reached MII at 30 h than in group I, but there was no difference in medium with or without EGF supplementation (81.8 and 79.8% respectively). Cytoplasmic maturation of MII oocytes was judged from their capability to activate and fertilize after ICSI. In group I, the rates of activation and normal fertilization were similar. However, in group II, significantly more oocytes underwent normal fertilization in the EGF-supplemented than the unsupplemented group (71.7 versus 45.6%, P < 0.05). The cleavage rates of the fertilized oocytes were similar in the sibling oocyte subgroups cultured with or without EGF supplementation, but the overall cleavage rates were higher in cumulus-intact compared to cumulus-denuded oocytes (88.9 versus 47.8%, P < 0.001). Thus, supplementation of the maturation medium with EGF and maintenance of the cumulus during culture improve the nuclear and cytoplasmic maturation of human oocytes in vitro.   相似文献   
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