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1.
BASIS: Fractures of the talus or calcaneus with accompanying soft tissue damage require precisely planned treatment to prevent infection of the wound over time, especially in severely injured patients. MATERIAL AND METHODS: Seven patients with fractures of the talus or calcaneus and accompanying 2nd and 3rd degree open or 3rd degree closed soft tissue injuries were followed up retrospectively. These patients were operated on between January 1999 and January 2006 with free fasciocutaneous scapular or parascapular flaps. The average age was 34 (range 16-54). Follow-up was at 6-36 months. RESULTS: Osteosynthesis was primarily in six cases, post-primarily in one, and in four cases exterior fixation was used additively. Temporary vacuum therapy was performed for a mean of 28 days (6-42). Parascapular, scapular, and Latissimus dorsi flap coverage was performed six, one, and one times, respectively. Six flaps healed without complication. One necrosis of a parascapular flap occurred and made a Latissimus dorsi flap necessary. In one case of donor-site wound dehiscense, a local rotation flap became necessary. There was no joint infection or osteomyelitis. Bony consolidation was achieved within all fractures. CONCLUSION: Traumatic soft tissue damage must be taken into account when primary or secondary internal fixation is performed and should influence the choice of implant. Free fasciocutaneous parascapular or scapular flaps are a powerful tool for preventing infection if local flaps are not sufficient to achieve stable soft tissue coverage.  相似文献   
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Previous studies of human thyroid cells in culture (mostly from pathological tissues) failed to demonstrate a mitogenic effect of TSH, leading to the proposal that the growth effect of TSH in vivo might be indirect. To reexamine the influence of TSH on DNA synthesis and cell proliferation, we established primary cultures of normal thyroid tissue from nine subjects. When seeded in a 1% serum-supplemented medium, thyroid follicles released by collagenase/dispase digestion developed as a cell monolayer that responded to TSH by rounding up and by cytoplasmic retraction. When seeded in serum-free medium, the cells remained associated in dense aggregates surrounded by few slowly spreading cells. In the latter condition, the cells responded to TSH and other stimulators of cAMP production, such as cholera toxin and forskolin, by displaying very high iodide-trapping levels. Exposure to serum irreversibly abolished this differentiated function. TSH stimulated the proliferation (as shown by DNA content per culture dish) of 1% serum cultured cells (doubling times were reduced from 106 to 76 h) and increased by 100% the [3H]thymidine labeling indices. In serum-free cultured cells (dense aggregates or cell monolayers after initial seeding with serum), control levels of DNA synthesis were lower, and up to 8-fold stimulation of DNA synthesis occurred in response to 100 mU/L TSH (stimulation was consistently detected with 20 mU/L), based on measurements of [3H]thymidine incorporation into acid-precipitable material and counts of labeled nuclei on autoradiographs (up to 40% labeled nuclei within 24 h). The mitogenic effect of TSH required a high insulin concentration (8.3 X 10(-7) mol/L) or a low insulin-like growth factor I concentration. The mitogenic effects of TSH were mimicked in part by cholera toxin, forskolin, and dibutyryl cAMP. Epidermal growth factor and phorbol myristate ester also stimulated thyroid cell proliferation and DNA synthesis, but they potently inhibited TSH-stimulated iodide transport. We conclude that TSH, acting at least in part through cAMP, is a potent growth factor for human thyroid cells and thus provide an experimental basis in vitro for the well established in vivo goitrogenic action of TSH.  相似文献   
3.
The aim of this study was to prospectively evaluate endoscopic ultrasonography and microscopic examination of duodenal bile in the diagnosis of cholecystolithiasis not detected by conventional ultrasonography. Forty five consecutive patients (26 females, 19 males, mean age: 50 years) with suspected cholecystolithiasis and at least two normal transcutaneous ultrasonography examinations were included. Endoscopic ultrasonographic criteria for the diagnosis of cholecystolithiasis were the presence of stones with or without acoustic shadowing or sludge. Criteria of microscopic examination of bile were cholesterol or bilirubinate crystals or spheroliths. Thirty three patients underwent cholecystectomy and lithiasis was found in gall bladder bile in 24. Twelve patients who were not operated on and were followed up (median: 17 months), had no evidence of cholecystolithiasis. Endoscopic ultrasonography and duodenal bile examination were 96% and 67% sensitive, respectively (p < 0.03). The specificity was not different (86 and 91%, respectively). None of the 16 patients with negative results in both procedures had evidence of cholecystolithiasis. It was found that for the diagnosis of cholecystolithiasis in patients with normal conventional ultrasonography, the sensitivity of endoscopic ultrasonography is higher than that of microscopic examination of duodenal bile. If endoscopic ultrasonography and microscopic examination of duodenal bile are negative, the risk of underdiagnosing cholecystolithiasis is negligible.  相似文献   
4.
1. The present study aimed to determine the feasibility of conducting a 5 year cardiovascular outcome trial of the treatment of 6000 elderly hypertensive patients in Australian general practices. 2. General practitioners (GPs) were invited to participate by mail and personal follow-up. Patient records were reviewed to identify subjects for a blood pressure (BP) screening programme. Blood pressure was measured on three occasions and eligible subjects were included if the average BP was 160 mmHg systolic or 90 mmHg diastolic if systolic BP was 140 mmHg. 3. Seven hundred and forty-one GPs were approached and 89 were enrolled in the study (12% of mail invites and 75% of those receiving a personal contact). In 16 practices where screening was completed, 82 000 records were reviewed to identify 4% patients eligible for screening. Twenty-two per cent of eligible subjects attended screening. Of 1938 subjects screened, 180 (9%) had BP 5=160/90 mmHg. Forty-seven percent of subjects (n = 916) were receiving antihypertensive therapy and 184 (20%) were withdrawn from therapy. One hundred and sixteen (63%) of these subjects had BP return to study entry levels within 6 weeks. Fifty-seven newly diagnosed and 81 previously treated subjects were randomized (7% of the screened population). 4. Based on the high participation rate of GPs, the response rate of patients to attend a BP screening programme and the 7% randomization to screening ratio for entry into the study, the ANBP2 pilot study has demonstrated that it is feasible to recruit subjects from Australian general practices to a cardiovascular outcome trial.  相似文献   
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This study describes the manipulation of secondary products arising from the synthesis of the prototypical molecular combination of 5-fluorouracil (5-FU) and chloroethylnitrosourea (CNU), B.3839, in order to investigate the effects produced by connecting the C-S-C-C-CNU chain to the 5-FU ring in different ways. The isolation of phthalimide precursors of these compounds and the transformation into CNUs is described. Anti-tumour activity of these molecular combinations against a series of experimental murine colon, lung and mammary tumours is presented. The spectrum of anti-tumour activity displayed is interesting but defies simple explanation without further detailed in vivo pharmacokinetic and metabolism studies in order to define optimal profiles for activity.  相似文献   
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Urea rebound and delivered Kt/V determination with a continuous urea sensor   总被引:3,自引:1,他引:2  
BACKGROUND: The recent introduction of urea sensors for dialysis monitoring has made possible new approaches to urea kinetic modelling. In this study we show how the equilibrated postdialysis urea concentration (Ceq) and Kt/V corrected for double-pool urea kinetics (Kt/Vdp) can be accurately determined using an on-line sensor providing a continuous measure of blood water urea. A modification of the Smye constant volume double-pool theory led to the following equations for Ceq and Kt/Vdp [formula: see text] where Cpre is the blood concentration measured at the start of dialysis, t is the length of the dialysis session (in min) and S(ex) is the constant slope of the blood urea logarithm concentration decline following development of the intercompartmental urea concentration gradient in the first 30-60 min of dialysis. METHODS: These equations were tested in 11 patients undergoing 165-240 min of paired filtration dialysis with continuous monitoring of blood urea concentration. Cpre was determined as the plateau concentration during a preliminary period of 15-20 min of slow isolated ultrafiltration. S(ex) was accurately determined from linear regression applied to the urea sensor data from the 80-min point to the end of dialysis. RESULTS: Ceq and Kt/Vdp determined from the above equations compared closely to values determined from 25-40 min of urea rebound monitoring with the urea sensor: 10.6 +/- 3.0 versus 10.8 +/- 2.7 mmol/l (mean +/- SD) for Ceq and 1.21 +/- 0.24 versus 1.18 +/- 0.20 for Kt/Vdp, compared to single-pool values of Kt/V = 1.34 +/- 0.23. CONCLUSION: This technique may be readily programmed into on-line urea monitors to provide current and extrapolated values of Ceq and Kt/Vdp from about the first hour of dialysis.   相似文献   
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