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Jonathan Koea M.D. F.R.A.C.S. Graeme Taylor F.R.C.P.A. Mary Miller F.R.C.P.A. Michael Rodgers F.R. A.C. S. John McCall M.D. F.R.A.C.S. 《Journal of gastrointestinal surgery》2003,7(5):627-630
Solitary necrotic nodule of the liver is an unusual lesion that is often an incidental finding on abdominal imaging, intraoperative
examination, or post mortem. Most reported cases of solitary necrotic nodule have been in males, and over three quarters of
these lesions have occurred in the right lobe of the liver. Pathologically, solitary necrotic nodule is a benign lesion characterized
by a completely necrotic core that is often partly calcified, surrounded by a dense hyalinized fibrous capsule containing
elastin fibres. The ultrasound appearance of solitary necrotic nodule is usually of a “target” lesion with a hyperechoic center,
while on CT scan they appear as non-enhancing hypodense lesions that are typical of metastatic adenocarcinoma or peripheral
cholangiocarcinoma. The impression of malignancy is further enforced with the finding of necrotic cellular material on biopsy
and the macroscopically hard and “gritty” nature of the nodules. Currently, permanent histopathology of solitary necrotic
nodules is the only accurate method of diagnosis. However, solitary necrotic nodules are usually of a bilobed or lobulated
shape that is unusual for malignant liver lesions, and they often lie in close proximity to hepatic inflow structures. Solitary
necrotic nodule should be suspected in liver lesions with this configuration, location, and on a biopsy showing a large amount
of necrosis. 相似文献
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Meningitis and cerebrospinal fluid (CSF) leak are serious complications of acoustic tumor surgery. Previous reports have varied in the incidence of and the predisposing factors to these complications. This study reviews a series of 723 acoustic tumors removed via the translabyrinthine approach at the House Ear Clinic in Los Angeles. The incidences of CSF leak and meningitis were 6.8% and 2.9%, respectively. The patients who developed these problems were compared to the remainder of the study population for differences in age at surgery, tumor size, operative time, and length of hospital stay. Meningitis occurred more frequently in larger tumors, and patients with either complication had a longer hospital stay. The presence of CSF leak did not predispose to meningitis. It is concluded that technical factors account for postoperative CSF leak and meningitis after translabyrinthine acoustic tumor removal. 相似文献
25.
Quantitative X-ray diffraction analysis of urinary calculi by use of the internal-standard method and reference intensity ratios 总被引:1,自引:0,他引:1
The internal-standard method and the powder diffractometer have been applied here to the quantitative determination of urinary stone constituents by x-ray diffraction (XRD). Reference intensity ratios determined for six stone substances were used in the reduction of intensity data. Constituent concentrations calculated for 21 stones were compared with values obtained from an element-sensitive technique. We conclude that XRD analysis alone cannot be regarded as a routine technique for the quantitative characterization of uroliths, but that semiquantitative XRD analysis supplemented by accurate quantitative elemental data is more suitable for the precise determination of true stone composition. 相似文献
26.
Emery M Rodgers MM Boerman J Fleming BC Howe J Pope M 《The Journal of orthopaedic and sports physical therapy》1989,10(11):441-447
This research was supported by a grant from The Foundation for Physical Therapy, Alexandria, VA. The purpose of this study was to determine the reliability of a quantitative measure of knee ligament laxity in vivo. The testing device simultaneously measures applied forces and resulting displacement at the knee through use of a multidimensional electrogoniometer, dynamometer, and a computer-assisted analysis system. Subjects were 30 females and 20 males, ranging in age from 18-32 years. Laxity tests were performed in the anterior/posterior (A/P) plane at 90 and 30 degrees of knee flexion, and the varus/valgus (V/V) plane at 20 and 0 degrees of knee flexion. Test-retest (N = 41) and intertester (N = 18) repeatability was assessed in all test positions by ANOVA and by coefficients of correlation and variability. No significant differences were found within testers for A/P or V/V tests 1 week apart at any angle tested. There were significant differences between testers for A/P and V/V tests. No significant differences were found between left and right sides, or between male/female values. Comparisons to other in vitro and in vivo studies are made. J Orthop Sports Phys Ther 1989;10(11):441-447. 相似文献
27.
This study examined the relationship between exercise motives and physical self‐esteem (PSE) in physically active females using Self‐Determination Theory (SDT; Deci & Ryan, 1985, 1995; Ryan & Deci, 2000). Female exercise participants recruited from university‐based exercise classes reported their motives for exercise during Week 2, and their levels of PSE during Week 12, of a 15‐week exercise class. Bivariate correlations indicated that exercise motives displayed a graded pattern of relationships. They also suggested that only autonomous exercise motives were associated with higher PSE. Discriminant function analysis revealed that more autonomous exercise motives correctly classified 83.3% of the high PSE group and 88.9% of the low PSE group. These findings support Ryan and Deci's assertions and suggest that autonomous exercise motives may play an important role in positive PSE in the exercise domain. These findings advance the application of SDT in the exercise domain and further our understanding of PSE development. 相似文献
28.
Comparisons between direct microscopic and cultural methods for recognition of Corynebacterium vaginale in women with vaginitis. 下载免费PDF全文
The frequency with which clue cells could be detected in Gram-stained vaginal smears and/or cervical Papanicolaou (Pap) smears was compared with the frequency of Corynebacterium vaginale (Haemophilus vaginalis) isolation in a group of 236 female patients, of whom 221 had vaginitis. Vaginal clue cells were found most often in women from whom C. vaginale was isolated (P = 0.00006) whereas, conversely, clue cells in cervical Pap smears were reported more frequently in women with negative cultures for this organism (P = 0.006). C. vaginale isolations were made more frequently from women with both vaginal and cervical clue cells reported (P = 0.000088). However, the combined false positive-false negative vaginal clue cell rate in the patients studied was 36.5%. Neither the detection of vaginal clue cells nor the isolation of C. vaginale was significantly affected by whether or not patients had trichomoniasis (P = 0.25). Trichomonas vaginalis detection in cervical Pap smears and vaginal isolation were related (P = 0.00005), whereas the same relationship was not significant for fungi (P = greater than 0.05). 相似文献
29.
Social conflict in mice is associated with at least two forms of analgesia. A long-lasting opioid reaction is evident in intruder mice exposed to prolonged attack, whilst an acute non-opioid analgesia is seen in response to either defeat experience per se or the territorial scent-marking of an aggressive conspecific. Recent work from this laboratory has suggested that the non-opioid analgesic reaction to defeat experience may be mediated via benzodiazepine receptor mechanisms. The present studies were designed to further test this tentative hypothesis. Results confirmed that defeat analgesia is dose-dependently blocked by Ro15-1788 (20-40 mg/kg) and diazepam (2-4 mg/kg), and also indicated partial antagonism of the reaction by CGS8216 (2.5 mg/kg). The partial agonists CGS9896 (2.5-20 mg/kg) and ZK91296 (2.5-20 mg/kg) were ineffective in blocking the reaction, a finding also obtained with the full agonist ZK93423 (0.05-10 mg/kg). However, the antagonist/weak inverse agonist ZK93426 was found to possess significant intrinsic analgesic activity (10 mg/kg) and to enhance defeat analgesia (5-10 mg/kg). Although several interpretative frameworks for the current pharmacological profile are considered, it is concluded that full clarification of the substrates of defeat analgesia must await further investigations. 相似文献
30.