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11.
We have shown that the oxidation rate of exogenous glycerol and glucose during prolonged exercise were similar when ingested in small amounts (0.36 g/kg) (J Appl Physiol 90:1685,2001). The oxidation rate of exogenous carbohydrate increases with the amount ingested. We, thus, hypothesized that the oxidation rate of exogenous glycerol would also be larger when ingested in large amount. The study was conducted on six male subjects exercising for 120 min at 64 (2)%VO2max while ingesting 1 g/kg of 13C-glycerol. Substrate oxidation was measured using indirect respiratory calorimetry corrected for protein oxidation, and from V 13CO2 at the mouth. The 13C enrichment of plasma glucose was also measured in order to follow the possible conversion of 13C-glycerol into glucose. In spite of the large amount of glycerol ingested and absorbed (plasma glycerol concentration = 8.0 (0.3) mmol/l at min 100), exogenous glycerol oxidation over the last 80 min of exercise [8.8 (1.6) g providing 4.1 (0.7)% of the energy yield] was similar to that observed when 0.36 g/kg was ingested. The comparison between the 13C enrichment of plasma glucose and the oxidation rate of 13C-glycerol showed that a portion of exogenous glycerol was converted into glucose before being oxidized, but also suggested that another portion could have been directly oxidized in peripheral tissues.  相似文献   
12.
Pulmonary histiocytosis X: comparison of radiographic and CT findings   总被引:6,自引:0,他引:6  
The authors retrospectively evaluated radiographs, computed tomographic (CT) scans, and results of pulmonary function tests (when available) for 17 patients with biopsy-proved pulmonary histiocytosis X. In 11 patients, high-resolution CT was used. In 12 patients, CT demonstrated cystic air spaces, usually less than 10 mm in diameter. In three of these 12, cysts were the only abnormality, but in six others, nodules (usually less than 5 mm in diameter) were also present. Two patients had only nodules and one, only emphysema. CT showed that many lesions that appeared reticular on plain radiographs were actually cysts. CT showed no central or peripheral concentration of lesions, but it did reveal that many small nodules were distributed in the centers of secondary lobules around small airways. CT findings correlated better with the diffusing capacity (rho = -0.71) than did the plain radiographic findings (rho = -0.57). Thus, CT was better than radiography at showing the morphology and distribution of lung abnormalities.  相似文献   
13.

Objectives

The aims of this study were (1) to compare the accuracy of the detection of approximal enamel caries lesions using three intraoral storage phosphor plate digital systems and one conventional film-based radiographic system; and (2) to determine whether there is a correlation between the histological and radiographic measurements of enamel caries.

Methods

160 approximal surfaces were radiographed under standardized conditions using three storage phosphor stimulable systems (DenOptix and Digora FMX with white and blue plates), and one film system (Insight film). 17 observers scored the images for the presence and depth of caries using a 4-point scale. The presence of caries was validated histologically (gold standard). Two-way analysis of variance was used to test the differences in sensitivity, specificity and overall accuracy (TP + TN). The data from the radiographic and histological measurements were statistically analysed by Spearman’s rank correlation coefficient.

Results

Two-way analysis of variance and the post hoc t-test demonstrated that Digora (white plate) had higher specificity and overall accuracy values than DenOptix (P = 0.021); there was no statistically significant difference among the other imaging modalities (P > 0.05). There was no significant correlation between the histological depth measurements and the radiographic measurements from Digora (blue plate) (P = 0.43), Digora (white plate) (P = 0.15), DenOptix (P = 0.17) and Insight film (P = 0.06).

Conclusions

The results suggest that (1) the performance of the three storage phosphor image plate systems was similar to that of the Insight film for detection of approximal enamel caries, and (2) the increase in histological depth of enamel caries was not significantly correlated with radiographic measurements.  相似文献   
14.
PURPOSE: To prospectively evaluate the sensitivity and specificity of contrast material-enhanced and water-enhanced multidetector computed tomographic (CT) enteroclysis in depicting small-bowel neoplasms in symptomatic patients, with endoscopic, tissue, and follow-up findings as reference standards. MATERIALS AND METHODS: The study protocol was approved by the Human Research Committee of the institution, and all patients gave written informed consent. Two hundred nineteen patients (108 male, 111 female; age range, 17-98 years; mean, 53.1 years) with clinical suspicion of small-bowel neoplasm underwent contrast- and water-enhanced multidetector CT enteroclysis after normal findings of upper and lower gastrointestinal endoscopy. The prospective interpretations of CT enteroclysis results include evaluation of focal bowel wall thickening, small-bowel masses, small-bowel stenosis, mesenteric stranding, enlarged mesenteric lymph nodes, and visceral metastasis. Positive enteroclysis findings were compared with results of pathologic examination after surgical (n = 35) or endoscopic (n = 20) procedures. Negative results were compared with results of surgery (n = 8), enteroscopy (n = 15), capsule endoscopy (n = 14), and clinical follow-up (n = 127). Sensitivity, specificity, accuracy, and positive and negative predictive values were calculated on a per-patient basis with 95% confidence intervals. RESULTS: Findings of CT enteroclysis were positive in 55 cases and negative in 164. The overall sensitivity and specificity in identifying patients with small-bowel lesions were 84.7% and 96.9%, respectively. The negative and positive predictive values were 94.5% and 90.9%, respectively. Findings of pathologic examination confirmed small-bowel tumor in 50 patients with carcinoid tumor (n = 19), adenocarcinoma (n = 7), lymphoma (n = 5), jejunal adenoma (n = 9), stromal tumor (n = 5), ectopic pancreas (n = 2), angiomatous mass (n = 2), or metastasis (n = 1). Five examinations resulted in false-positive findings. CONCLUSION: Contrast- and water-enhanced multidetector CT enteroclysis had an overall accuracy of 84.7% for depiction of small-bowel neoplasms.  相似文献   
15.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
16.
A comprehensive anatomic and radiographic analysis of the peribursal fat plane in 12 cadavers confirmed that the fat plane seen on radiographs represents extrasynovial fat lining the subacromial bursa and documented the anatomic relations of the bursa. A three-part retrospective clinical evaluation of rotator cuff tears, calcific tendinitis, and rheumatoid arthritis was performed. Two osteoradiologists blindly graded the appearance of the peribursal fat plane with the shoulder in external versus internal rotation in 21 patients with arthrographically intact rotator cuffs and 21 patients with disrupted rotator cuffs. The peribursal fat plane was seen better with disrupted rotator cuffs. The peribursal fat plane was seen better with the shoulder in internal rotation and was seen in 60% of control subjects but only 21% of patients with rotator cuff tears. Partial or complete obliteration of this fat plane is a sensitive (79%) but less specific (60%) indicator of rotator cuff tears. Obliteration of the peribursal fat plane by inflammatory processes in adjacent tissues, including calcific tendinitis and rheumatoid arthritis, occurred with a high frequency.  相似文献   
17.
18.

Background:

Patellar dislocations are either due to superolateral contracture of the soft tissue or imbalance of the power between the vastus medialis (VM) and the vastus lateralis (VL). The imbalance of muscle power as an etiology of patellar dislocation has not been studied. Hence, we studied the recurrent, habitual and permanent dislocations of the patella with an electromyogram (EMG) of the vastus medialis, vastus lateralis, and pes anserinus, before and after realignment operations, to document the muscle imbalance and effectiveness of the realignment operation.

Materials and Methods:

An electromyographic investigation was carried out on the vastus medialis and vastus lateralis in nine recurrent, 20 habitual, and 13 permanent dislocations of the patella, before and after their realignment operations. Pes anserinus transposition, which acted as a medial stabilizer of the patella, was also investigated with an EMG study, to understand its role on patellar stability at 0°, 30°, 60°, 90°, 120°, 150°, and full flexion of the knee. The age of the patients varied from nine to 30 (mean 15) years. There were 24 males and 18 females. Twenty-six patellar dislocations were on the right and 16 were on the left side.

Results:

Electromyographic pictures reveal subnormal activity of the vastus medialis in all types of dislocations and similar activities of the vastus lateralis in permanent and habitual dislocations recorded pre operatively, which recovered to almost normal values postoperatively, at the mean one-year follow-up. Pes anserinus, which was used for medial stabilization of the patella after its realignment, maintained normal EMG activity before and after the operation.

Conclusion:

This study is significant for understanding the imbalance of muscle activities in patients with an unstable patella, which can be rectified without recurrence after pes anserinus transposition.  相似文献   
19.
Background

Incisional hernia (IH) may occur in 20% of patients after laparotomy. The hernia sac volume may be of significance, with reintegration of visceral contents potentially leading to repair failure or abdominal compartment syndrome. The present study aimed to evaluate a two-step surgical strategy comprising right colectomy for hernia reduction with synchronous absorbable mesh repair followed by definitive non-absorbable mesh repair in recurrence.

Methods

Patients operated between 2012 and 2017 at two university centers were retrospectively included. Volumetric evaluation of the IH was performed by CT imaging.

Results

Eleven patients were included. The mean BMI was 43 kg/m2 (23–52 kg/m2). Progressive preoperative pneumoperitoneum was performed in 82% of patients, with complications in 22%. The mean volumetric ratio of the volume of the hernia to the volume of the abdominal cavity was 70% (48–100%). The first parietal repair was performed using an synthetic absorbable mesh (36%), a biologic mesh (27%), or a slowly absorbable mesh (36%). No patients died as a result of the procedure. Seven (64%) patients developed grade III–IV complications, including one case of an anastomotic fistula. Recurrence occurred in eight (73%) patients after the first repair. Of these, four (50%) patients were reoperated using a non-absorbable mesh, leading to solid repair in 75% of cases. After 27 ± 18 months of follow-up, the residual IH rate was 46%.

Conclusions

Right colectomy for volume reduction in IH with loss of domain potentially represents an appropriate salvage option, supporting bowel reintegration and temporary hernia repair with absorbable material.

  相似文献   
20.

Background

Turnbull–Cutait abdominoperineal pull-through followed by delayed coloanal anastomosis (DCA) was first described in 1961. Studies have described its use for challenging colorectal conditions. We reviewed our experience with Turnbull–Cutait DCA as a salvage procedure for complex failure of colorectal anastomosis.

Methods

We performed a retrospective cohort study from October 2010 to September 2011, with analysis of postoperative morbidity and mortality.

Results

Seven DCAs were performed for anastomotic complications (3 chronic leaks, 2 rectovaginal fistulas, 1 colovesical fistula, 1 colonic ischemia) following surgery for rectal cancer. Six patients had a diverting ileostomy constructed as part of previous treatment for anastomotic complications before the salvage procedure. No anastomotic leaks were observed. All procedures but 1 were completed successfully. One patient who underwent DCA subsequently required an abdominoperineal resection and a permanent colostomy for postoperative extensive colonic ischemia. No 30-day mortality occurred.

Conclusion

Salvage Turnbull–Cutait DCA appears to be a safe procedure and could be offered to patients with complex anastomotic complications. This procedure could be added to the surgeon’s armamentarium as an alternative to the creation of a permanent stoma.  相似文献   
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