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31.
Gastroduodenoscopy and retrograde cholangiopancreatography has been performed on 25 occasions in 20 children aged between 7 and 16. Radiographs of the clinically relevant duct or ducts were achieved in 96% of attempts, with no complications. The diagnostic information proved useful clinically; in particular it provided a precise map if biliary or pancreatic surgery was being contemplated. Several unexpected congenital duct anomalies were found. This and other recent reports, particularly from Germany, indicate that endoscopic retrograde cholangiopancreatography deserves greater application in children, and can also be used in babies.  相似文献   
32.
The purpose of this study was to demonstrate microstructural differences between clinically similar, but aetiologically different, cases of corneal oedema in four subjects. In vivo confocal microscopy highlighted oedema of the basal epithelium, prominent nerve–keratocyte interactions, and typical ‘epithelialization’ of the endothelium in a case of iridocorneal endothelial syndrome; however, a similar microstructural appearance was observed in a case of presumed herpetic disciform keratitis. The latter diagnosis was subsequently revised on this basis. Confocal examination of Fuchs’ endothelial dystrophy demonstrated oedema of the basal epithelium, prominent wing cells, anterior stromal alterations, fibrosis of Descemet’s membrane and a typical ‘strawberry’ appearance of the endothelium. In contrast, in vivo microstructural examination of bilateral keratoconus with hydrops confirmed oedema mainly involving the epithelium and anterior stroma. In vivo confocal microscopy allows the clinician to observe the living cornea at a microstructural level and to better diagnose and differentiate borderline or unusual cases of corneal oedema.  相似文献   
33.
Digital beam attenuator technique for compensated chest radiography   总被引:1,自引:0,他引:1  
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone.  相似文献   
34.
We describe the corneal microstructural changes in a patient with spheroidal degeneration using in vivo confocal microscopy. Multiple hypo‐ and hyper‐reflective spherical lesions were observed in the anterior corneal stroma and Bowman's layer ranging from 45 to 220 μm in size. The corneal epithelium, posterior stroma and endothelium were otherwise unaffected. In vivo confocal microscopy demonstrates good correlation with excised histological samples in climatic droplet keratopathy. It provides a non‐invasive technique to examine the living cornea for degenerative disease and acts as a bridge between clinical and laboratory observations.  相似文献   
35.
Computer-assisted planimetry, computer-assisted lineal analysis, and point-counting stereology have been compared with respect to their reproducibility and the time required to analyze bone-implant integration. Sections of 6 threaded dental implants selected from a bone augmentation experiment for their wide range of new bone formation were analyzed by each method 3 times. The bone density and percentage of osseous integration were evaluated at 4 sites around each implant section. It was found that computer-assisted planimetry demonstrated a modest but significantly greater variance (P < .05) in bone density estimates when compared to the computer-assisted lineal analysis and point-counting methods. Computer-assisted planimetry requires a different method of measuring each parameter and separate fields of view to evaluate fields distant from the implant. However, this can all be accomplished with line probes, as in computer-assisted lineal analysis, which extend from the implant surface into the surrounding alveolar bone. Whereas computer-assisted planimetry requires a separate identification of the perimeter of each field to be analyzed (next to and distant from the implant), computer-assisted lineal analysis allows expansion of the field to be evaluated without creating a new field of view. Also, following a limited learning curve, both point-counting and computer-assisted lineal analysis required less time to complete than did computer-assisted planimetry.  相似文献   
36.
11 adult patients with moderate to advanced periodontitis were treated with oral hygiene instruction and an initial, single episode of root debridement. Before therapy, 3 independent clinicians examined all patients and identified sites that in their opinion probably would not respond to the therapy and would continue to lose attachment. On 2 occasions, 3 and 12 months later, the clinicians re-examined and re-evaluated all patients and all sites. The results of therapy were also monitored by probing attachment level measurements performed every 3rd month. All 11 patients completed 24 months of follow-up, and 6 subjects were available until 36 months. Sites with probing attachment loss after 12, 24 and 36 months were identified using linear regression analysis and compared to the clinicians' prediction of probing attachment loss. The results demonstrated a limited agreement between probing attachment loss determined by linear regression and the clinicians' predictions of probing attachment loss. It appears that the traditional clinical signs and factors used to forecast and identify periodontal disease activity are only moderately associated with probing attachment loss. This suggests that attachment loss may be caused by several factors, at least following initial therapy. The progression of an inflammatory disease of microbial etiology may be only 1 of such causes. Further studies are needed to clarify the nature and cause of probing attachment loss.  相似文献   
37.
We describe a young man who developed extensive hypothalamicdysfunction including diabetes insipidus, adipsia, hyperprolactinaemia,and poikiliothermia together with central sleep apnoea followingexposure to toluene.  相似文献   
38.
The in vitro and in vivo effects of cryopreservation on the cytotoxic activity of murine lymphokine-activated killer (LAK) cells were studied. LAK cells were generated by incubation of spleen lymphocytes of BALB/c mice for 3 days with recombinant interleukin-2 (rIL-2) and subsequent cryopreservation. Cytotoxicity was determined in a 51Cr release assay. After thawing, cytotoxic activity was reduced (40.4% 51Cr release at an effector:target cell ratio of 40:1 as compared to 68.5% 51Cr release before freezing) and could be restored to precryopreserved levels by reincubation with rIL-2 for 2 days after thawing (78.8% 51Cr release). These cells were then tested in BALB/c mice injected with RAW 112 cells, a pre-B-cell lymphoma line. The results demonstrate that the survival rate of mice injected with cryopreserved and restimulated LAK cells (50% survival greater than 180 days after injection) did not differ significantly from that of mice injected with fresh unfrozen LAK cells (60% survival greater than 120 days, 50% survival greater than 180 days). Cryopreserved LAK cells have potential use in adoptive immunotherapy.  相似文献   
39.

INTRODUCTION

Patient-directed information available on the internet is not always regulated; it may be confusing and sometimes just overwhelming. We aimed to establish the proportion of patients undergoing two common surgical procedures, who searched the internet for information about their operations and to assess the usefulness of the information they received.

PATIENTS AND METHODS

A total of 105 consecutive patients undergoing elective abdominal wall hernia repair (n = 54) or laparoscopic cholecystectomy (n = 51) in a single surgical firm were included in the study. Patients were counselled about their operation in pre-operative assessment clinics and standard trust information leaflets were provided without any mention of this study. Patients were then asked to complete a questionnaire on the morning of their operation.

RESULTS

All patients completed the questionnaire. Of the patients, 59% stated that they had access to the internet and 77% of these accessed the internet over 2 h a week. Of the patients with internet access, 31% used it to acquire additional information about their operations and 58% used internet search engines. Of the patients who searched the internet regarding their operations, 26% were confused and/or worried by the information they received.

CONCLUSIONS

A significant proportion of patients undergoing common surgical procedures used the internet and about one-third of them specifically sought information about their operation on the internet. Such information can cause worry and confusion in patients. Our study highlights the need for regulated, comprehensible, patient information on hospital websites to which patients should be directed.  相似文献   
40.

Background and purpose:

The function of transporters in peripheral blood mononuclear cells (PBMC) has been characterized, but less is known about cytochrome P450 (CYP) enzyme function in these cells. Given that cytokines are dysregulated in many diseases, the purpose of this work was to assess the impact of cytokines on the expression of CYPs, transporters and chemokine receptors in PBMC.

Experimental approach:

Human PBMC were incubated with cytokines for 48 h. ATP-binding cassette (ABC)B1, ABCC1, ABCC2, CYP2B6, CYP3A4, CXCR4 and CCR5 expression were measured by quantitative polymerase chain reaction and flow cytometry at 0, 4, 8, 24 and 48 h. Enzyme activity was assessed using fluorescent probes.

Key results:

We show here functional activity of CYP3A4 and CYP2B6 in PBMC. Furthermore, cytokines had a significant impact on the mRNA and protein expression of all proteins. For example, interleukin-2 (IL-2) had a marked impact on ABCB1 mRNA (% control 4745 ± 11961) and protein (% control 200 ± 57). Increases in drug efflux transporter expression, in response to cytokines, resulted in reduced cellular accumulation of digoxin [decrease of 17% and 26% for IL-2 and interferon-γ (IFNγ) respectively] and saquinavir (decrease of 28% and 30% for IL-2 and IFNγ respectively). The degree to which drug transporter and chemokine receptor expression changed in response to cytokines was positively correlated (e.g. ABCB1 and CXCR4, r2 = 0.545).

Conclusions and implications:

These data have important implications for diseases in which cytokines are dysregulated and for which pharmacological intervention targets immune cells.  相似文献   
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