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Indwelling urethral catheter placement is a common and comparatively safe procedure. Misplacement of a urethral catheter into the upper urinary tract is unusual, and only a few cases have been reported. We describe the case of a 43-year-old man who presented with oliguria and had a history of chemotherapy for known metastatic lung cancer. As he had no history of urological disease, urethral catheterization was expected to be uneventful. The catheter was unable to be pulled back to the bladder neck once the balloon was inflated, and the patient expressed discomfort. Subsequent computed tomography revealed that the tip of the catheter was placed in the middle of the right ureter. Unbeknownst to the physicians before urethral catheterization, the patient had severe lower urinary tract symptoms and urinary bladder dysfunction with hydronephrosis, likely due to chemotherapy. Based on the patient’s symptoms and imaging results, we judged the possibility of severe ureteral injury to be low. The malpositioned catheter was removed uneventfully after complete balloon deflation and then reinserted properly. He was admitted to the medical department but died as a result of an exacerbation of the underlying disease unrelated to the incident. If urethral catheter placement seems abnormal, physicians should aspirate and irrigate to confirm correct positioning before balloon inflation; then, they should carefully pull the inflated balloon near the neck of the bladder while monitoring the patient’s symptoms. Although urethral catheter placement is comparatively safe, physicians must keep in mind that patients who have undergone chemotherapy might be at a risk for this rare complication.  相似文献   
84.
Akt/protein kinase B (PKB) plays an important role in cell survival. However, the role of Akt in the biology of gastric cancer has not been well studied. We sought to investigate the expression of Akt or phosphorylated Akt (pAkt) in human gastric carcinomas and to analyze the relationship between Akt or pAkt and the clinicopathologic parameters. The expressions of Akt and pAkt were evaluated immunohistochemically in 311 gastric carcinomas using the tissue array method. Akt expression was detected in 74% of the tumors and pAkt expression in 78%. pAkt was highly expressed in the early stage of pTNM (p=0.011). We also found an inverse association between pAkt and lymphatic invasion (p=0.01) or lymph node metastasis (p=0.008). pAkt expression was significantly correlated with a higher survival in patients with stage I carcinomas (p=0.0003). Interestingly, combined evaluation revealed that the group with pAkt-positive and lymph node-negative carcinomas showed a better prognosis than the other groups (p<0.0001). In addition, pAkt was shown to correlate positively with APC (p=0.002) and Smad4 (p<0.0001) expression. These findings suggest that pAkt expression may help to predict the clinical outcome of gastric cancer patients.  相似文献   
85.
Transfer of immunoglobulins and antibodies in the hen's egg   总被引:5,自引:0,他引:5       下载免费PDF全文
T. T. Kramer  H. C. Cho 《Immunology》1970,19(1):157-167
The presence of immunoglobulins and antibodies were investigated in the fertile hen's egg during embryogenesis. The egg yolk, egg albumin, amniotic and allantoic fluids, chick embryo serum and intestinal contents were examined for the presence of immunoglobulin and level of antibodies.

Immunoglobulin G was not detected in fresh egg albumin, but appeared in the albumin from the 4th day of embryogenesis and persisted through the 16th day. The antibody profile of egg albumin during embryogenesis attained two peaks, which were separated by a trough on the 8th day of embryogenesis. The immunoelectrophoretic pattern of albumin IgG was different from that of egg yolk IgG.

The IgG of chick embryo serum was of γ2 mobility on the 12th day of incubation and shifted gradually to the full range of γ1 and γ2 mobilities on the 20th day of incubation. Egg-transmitted antibodies appeared on the 12th day of incubation and attained peak values on the 16th day of incubation.

Moderate antibody levels were detected in the amniotic and allantoic fluids from the 12th to the 18th days of incubation.

  相似文献   
86.
A I Vinik  A R Moattari  K Cho  N Thompson 《Surgery》1990,107(3):246-255
We review here the 10-year experience at the University of Michigan with 35 patients with gastrin hypersecretion who underwent transhepatic venous sampling (THVS) for tumor localization. Since 1978 THVS has been done routinely in all patients with gastrinoma syndrome considered for operation. Thirty-one patients had proved gastrinomas--21 benign sporadic tumors and 10 tumors associated with multiple endocrine neoplasia type-I (MEN I) syndrome. The correlation between the site of the maximal gradient and location of a sporadic tumor was poor. Overall sensitivity was only 35%, specificity 89%, and negative predictive value 89%. If gradients were regionalized to three areas--body and tail, gastrinoma triangle, and hepatic lobes--then sensitivity was 94%, positive predictive value 94%, and specificity 97%, with a negative predictive value of 97%. The maximal gastrin gradient above the mean for other values gave the greatest sensitivity and specificity. In MEN I syndrome, only four of eight patients with macroadenomas had their tumors correctly localized, a sensitivity of 50% and specificity and negative predictive value of 75%. In 19 patients who had operative localization of sporadic gastrinoma, computed tomography had a sensitivity of 31%, specificity of 66%, positive predictive value of 83%, and negative predictive value of 15%. Selective angiography was better, with a sensitivity of 29%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 100%. Regionalization to the triangle proved valuable for detection of microgastrinomas, as was measurement of hepatic vein gastrins for identification of intrahepatic tumors. In MEN I syndrome, if regionalization was achieved (50%), tumor resection appeared to offer hope of "cure." We conclude that THVS is the best tool for tumor regionalization to the pancreatic tail and body, gastrinoma triangle, and hepatic lobes. It has allowed us to achieve surgical cure in 19 of 21 patients with sporadic gastrinomas and improvement in four of eight patients with MEN I syndrome.  相似文献   
87.
An analytic formalism utilizing a convolution technique is presented for the incorporation of anisotropy corrections into the dynamic (or transit) dose calculations in high dose rate (HDR) brachytherapy. A simple numerical implementation of the suggested formalism is also presented. Two calculational examples are provided in order to show some effects of anisotropy corrections on the dynamic dose calculations. Based on the results from these examples and published literature, the absence of anisotropy corrections in the dynamic dose calculations could result in a dosimetric error up to the order of 0.1 Gy during the full course of HDR brachytherapy treatments depending on fractionation and geometrical arrangement. Therefore, the incorporation of anisotropy corrections into dynamic dose calculations could eliminate this kind of error in HDR brachytherapy.  相似文献   
88.
Epicardial fat may anteriorly produce an echo-free space that can be mistaken for pericardial fluid. We recently experienced a 67-year-old woman with prominent epicardial fat which was presented as an echogenic tumor-like mass. She underwent open pericardiostomy to relieve large amount of pericardial effusion. Operative findings revealed only prominent epicardial fat. Biopsy of the pericardial and fat tissues revealed an inflammation and normal fat cells without any malignant cell infiltration.  相似文献   
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PURPOSE: Collision tumors represent a coexistence of two adjacent but histologically distinct tumors without histologic admixture in an organ. The purpose of this study was to describe the imaging findings of collision tumors of the ovary associated with teratoma and to look for clues that might lead to the correct preoperative diagnosis. METHOD: Seven pathologically proven cases of collision tumor of the ovary associated with teratoma were retrospectively reviewed. Ovarian teratomas were coexistent with mucinous cystadenoma (n = 4), borderline mucinous tumor (n = 1), mucinous cystadenocarcinoma (n = 1), and dysgerminoma (n = 1). US (n = 5), CT (n = 3), and/or MRI (n = 4) findings were evaluated. RESULTS: In addition to the typical findings of teratoma, the mass contained a multiloculated cystic portion filled with nonfatty fluid, suggesting the coexistent epithelial tumor in five cases. In one case, the mass contained a large solid component, suggesting the possibility of collision tumor. In the remaining one case, coexistent small mucinous cystadenoma could not be identified. CONCLUSION: Preoperative imaging for ovarian teratoma revealed a collision tumor in six of seven cases. The possibility of a collision tumor should be considered when an ovarian teratoma has imaging findings that cannot be explained solely by an ovarian teratoma.  相似文献   
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