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21.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
22.
This article reviews the experience available to date on microcirculation assessment in cancer of the cervix including correlation studies of magnetic resonance (MR) microcirculatory parameters with histo-morphometric predictors and direct correlation with patient outcome. The data suggest that MR microcirculation parameters do not always correlate with histo-morphometric parameters, while there is evidence that MR parameters predict patients' treatment outcome. These observations raise the issue that perhaps the histo-morphometric parameters, accepted gold standards for tumor angiogenesis and prognostic factors, reflect anatomical information at a "static" single time point and may not always provide sufficient information on the "dynamic" microcirculation function of the tumor. MR microcirculation assessment reflects both anatomical and functional information and may provide this additional information on the "dynamic" angiogenic and metabolic status of a tumor. Therefore, assessment of tumor microcirculation may augment the individual risk profile in cervical cancer patients and has the potential to impact on therapy selection and treatment outcome.  相似文献   
23.
One-hundred and eight-five pairs of gas samples were collected from inspired gas (10 cm behind the head at nose level) and end-tidal gas of persons administering anesthesia in 3 operating rooms during daily routine anesthesia. Mean operating-room N2O concentrations from 22 to 144 ppm (volume/volume [V/V]) were measured by gas chromatography, and large moment-to-moment variations (temporal gradients) were seen in individual operating rooms. Mean end-tidal N2O concentrations from 51 to 114 ppm (V/V) were observed. There were low correlations between inspired and end-tidal N2O concentrations (r values as low as r = 0.35). This poor relationship is presumably due to spatial and temporal gradients of N2O in the operating rooms. We conclude that the temporal and spatial gradients in N2O concentrations within active operating rooms are sufficiently large to invalidate estimation of exposure of anesthetic personnel to N2O from "spot" or "grab" samples collected in the breathing area.  相似文献   
24.
25.
Briefly trained physicians assistants using protocols (clinical algorithms) for diabetes, hypertension, and related chronic arteriosclerotic and hypertensive heart disease abstrated information from the medical record and obtained history and physical examination data on every patient-visit to a city hospital chronic disease clinic over a 18-month period. The care rendered by the protocol system was compared with care rendered by a "traditional" system in the same clinic in which physicians delegated few clinical tasks. Increased thoroughness in collecting clinical data in the protocol system led to an increase in the recognition of new pathology. Outcome criteria reflected equivalent quality of care in both groups. Efficiency time-motion studies demonstrated a 20 per cent saving in physician time with the protocol system. Coct estimates, based on the time spent with patients by various providers and on the laboratory-test-ordering patterns, demonstrated equivalent costs of the two systems, given optimal staffing patterns. Laboratory tests were a major element of the cost of patient care,and the clinical yield per unit cost of different tests varied widely.  相似文献   
26.
The use of radiotherapy for plantar fasciitis has never been reported in Australasia and is scarcely found in the English language medical literature, but it is commonly used in Europe, especially in Germany. In Europe, treatment courses consisting of multiple small fractions have been associated with high levels of pain relief. In the present report, the use of single fractions or radiotherapy was evaluated by reviewing seven consecutive patients referred for treatment and by applying objective and subjective criteria for pain relief. One patient died of unrelated causes soon after treatment and one declined to receive radiotherapy. Four patients each received a single dose of 8 Gy resulting in complete pain relief. One patient was treated with 8 Gy and 12 weeks later was retreated achieving partial pain relief. A follow‐up interview was conducted after a mean of 15.6 months, ranging from 1.5 to 30 months. No acute or late effects occurred; however, the possibility that delayed effects may yet occur, particularly carcinogenesis, cannot be excluded. Radiotherapy for this common condition should be investigated further as it might be safer and more effective than other methods currently in use.  相似文献   
27.
OBJECTIVE: To evaluate the impact of zinc supplementation on the clinical course, stool weight, duration of diarrhoea, changes in serum zinc, and body weight gain of children with acute diarrhoea. DESIGN: Randomised double blind controlled trial. Children were assigned to receive zinc (20 mg elemental zinc per day) containing multivitamins or control group (zinc-free multivitamins) daily in three divided doses for two weeks. SETTING: A diarrhoeal disease hospital in Dhaka, Bangladesh. PATIENTS: 111 children, 3 to 24 months old, below 76% median weight for age of the National Center for Health Statistics standard with acute diarrhoea. Children with severe infection and/or oedema were excluded. MAIN OUTCOME MEASURES: Total diarrhoeal stool output, duration of diarrhoea, rate of weight gain, and changes in serum zinc levels after supplementation. RESULTS: Stool output was 28% less and duration 14% shorter in the zinc supplemented group than placebo (p = 0.06). There were reductions in median total diarrhoeal stool output among zinc supplemented subjects who were shorter (less than 95% height for age), 239 v 326 g/kg (p < 0.04), and who had a lower initial serum zinc (< 14 mmol/l), 279 v 329 g/kg (p < 0.05); a shortening of mean time to recovery occurred (4.7 v 6.2 days, p < 0.04) in those with lower serum zinc. There was an increase in mean serum zinc in the zinc supplemented group (+2.4 v -0.3 mumol/l, p < 0.001) during two weeks of supplementation, and better mean weight gain (120 v 30 g, p < 0.03) at the time of discharge from hospital. CONCLUSIONS: Zinc supplementation is a simple, acceptable, and affordable strategy which should be considered in the management of acute diarrhoea and in prevention of growth faltering in children specially those who are malnourished.  相似文献   
28.
Mindfulness-based interventions can successfully target negative perseverative cognitions such as worry and thought suppression, but their acceptability and effectiveness in people with long-term conditions is uncertain. We therefore pilot tested a six-week meditation and mindfulness intervention in people (n = 40) with diabetes mellitus and coronary heart disease. We used a sequential mixed-methods approach that measured change in worry and thought suppression and qualitatively explored acceptability, feasibility, and user experience with a focus group (n = 11) and in-depth interviews (n = 16). The intervention was highly acceptable, with 90% completing ≥5 sessions. Meditation and mindfulness skills led to improved sleep, greater relaxation, and more-accepting approaches to illness and illness experience. At the end of the six-week meditation course, worry, and thought suppression were significantly reduced. Positive impacts of mindfulness-based interventions on psychological health may relate to acquisition and development of meta-cognitive skills but this needs experimental confirmation.  相似文献   
29.
Stoll  D; Cines  DB; Aster  RH; Murphy  S 《Blood》1985,65(3):584-588
We studied ten normal subjects and 20 patients with stable, untreated idiopathic thrombocytopenic purpura (ITP) and platelet counts in the range of 35,000 to 110,000/microL. The diagnosis was made by clinical criteria. Platelet-associated IgG was increased in all nine of the nine patients studied. Autologous platelets were labeled with chromium 51 and reinfused for measurement of mean cell life and platelet production rate. Mean cell life was calculated by two methods, weighted mean and multiple hit, with excellent agreement between the two. As expected, mean cell life was significantly reduced in ITP patients as compared to the normal subjects (2.9 days v. 8.0 days, P less than .001). However, mean platelet production rates in ITP patients and normal subjects, 3.5 and 3.8 X 10(9) platelets/k/d respectively, were not significantly different. Platelet production rate was above and below the normal range (2 to 5.6 X 10(9) platelets/k/d) in two and four patients, respectively. We conclude that the rate of platelet production is not increased in most patients with ITP who have platelet counts greater than 35,000/microL. We did find that platelet size was increased in eight of the 12 patients in whom it was measured, including two of the patients with low platelet production.  相似文献   
30.
Lipoprotein cholesterol/triglyceride ratio changes have been observed previously with sex hormone use. To determine if the lipoprotein cholesterol/triglyceride ratio is similarly changed by pregnancy and postpartum lactation, we examined pregnant subjects at 36 weeks gestation and the same women at 6 weeks postpartum and compared them to age-matched, nonpregnant women using or not using oral contraceptives. The cholesterol/triglyceride ratios were examined as means and medians and as curvilinear functions of increasing triglyceride concentration. Median ratios did not predict all ratio changes identified graphically. At very-low-density lipoprotein (VLDL) triglyceride concentrations below 40 mg/dL, the VLDL ratio is less than control in oral contraceptive users and further reduced in pregnant women. Above triglyceride concentrations of 40-60 mg/dL, the curves in the three groups are indistinguishable. No effect of lactation is observed. The low-density lipoprotein (LDL) cholesterol/triglyceride ratio is comparably lower in pregnant subjects and oral contraceptive users at all concentrations of lipoprotein triglyceride and again there is no effect of lactation. In high-density lipoprotein (HDL), there is no effect of either pregnancy or oral contraceptive use on the cholesterol/triglyceride ratio, while it is significantly higher with lactation. Postpartum decreases in the VLDL and LDL cholesterol/triglyceride ratio are seen at all lipoprotein concentrations independent of lactation. We conclude that triglyceride enriches VLDL at low concentrations and LDL at all concentrations in pregnancy and with oral contraceptive use, suggesting a common, hormonal mechanism. HDL is enriched with cholesterol during postpartum lactation, consistent with decreased transfer of cholesterol to other lipoproteins.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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