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991.
Summary Under normal biological conditions, immunoglobulin light chains are generally formed in conjunction with heavy chains; however, small quantities of free light chains are also produced. Thus, two types of immunoglobulin light chains may be identified; immunoglobulin-bound light chains and free light chains. In mature neoplastic B cells, immunoglobulin synthesis, including that of the free light chain, is generally increased. Furthermore, elevated free light chain levels also occur in the presence of renal glomerular and tubular impairment. Thus, the quantitative and qualitative measurement of free light chains is of considerable clinical benefit. Although methods for measurement of free light chains do exist, they are technically complicated and time consuming. Previously, we have reported a quantitative nephelometric immunoassay for measuring free light chain levels. We report here a refinement of this method using latex agglutination techniques. This new method enables quantitative measurement of free light chains in serum at levels as lows as 1 mg/l and may allow the clinical application of serum free light chain estimation.  相似文献   
992.
A 42‐year‐old woman presented with abdominal pain. On the basis of CT results, we diagnosed her condition as bowel obstruction caused by advanced transverse colon cancer. Colonoscopy findings showed three lesions: (i) an advanced tumor in the transverse colon; (ii) a laterally spreading descending colon tumor; and (iii) a rectal polyp. The tumors and the polyp were all pathologically diagnosed as adenocarcinoma. After inserting a self‐expanding metallic stent into the main tumor of the transverse colon to decompress the bowel, we performed endoscopic submucosal dissection of the laterally spreading descending colon tumor. Pathological examination results showed submucosal invasion and a positive margin. Because we endoscopically identified that the rectal polyp was invading the submucosa, we performed laparoscopic subtotal proctocolectomy and ileorectal anastomosis with lymph node dissection along the surgical trunk; we also performed central vascular ligation of the ileocolic artery, right and left branches of the middle colic artery, and inferior mesenteric artery. The patient's postoperative course was uneventful. We present this case because there have been few reports on laparoscopic subtotal or total proctocolectomy for synchronous multiple colorectal cancers.  相似文献   
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995.
The effect of guidewire bias on angled-lesion ablation by rotational atherectomy (RA) was assessed by measuring the changes in vertical lumen diameter, horizontal lumen diameter and the intima-media thickness of the coronary artery, using intravascular ultrasound in 10 lesions with an angle greater than 10 degrees. The vertical and horizontal diameters significantly increased after RA. The intima-media thickness at the 4 orthogonal sites significantly decreased. There was a significant positive correlation between vertical diameter change and angle (r=0.642, p=0.045), but none between horizontal diameter change and angle. There was no correlation between intima-media thickness change at 0 degrees and angle; however, at 180 degrees there was a tendency to correlation with angle (r=0.602, p=0.066). These data suggest that in cases of angled lesions, the increase in vertical lumen diameter is caused more by ablation of the 180 degrees wall than by that of the 0 degrees wall, which is brought about by guidewire bias toward the vascular wall at 180 degrees.  相似文献   
996.
Eighteen cases of mesenteric panniculitis of the colon collected from the literature, together with two cases from the authors' source, were reviewed. The disease occurred most often in late adult life, with a male predominance. Symptoms were abdominal pain, diarrhea, constipation, and a lower abdominal mass in most patients. Barium enema disclosed narrowing, shortening, and poor extensibility of the colon, and ultrasonography and computed tomography showed thickening of the mesocolon and colonic wall with soft-tissue density. Exploratory laparotomy was done in all patients, and colectomy, colostomy, or other surgical treatments were performed in 17 (85 percent). Gross appearance at the time of surgery was characterized by a marked thickening or a firm mass of the mesocolon with a puckered surface involving the appendices epiploicae of the colon. Microscopically, degeneration of the adipose tissue, revealed by aggregates of lipid-laden macrophages, was diagnostic. Inflammatory infiltration and fibrosis also were present in many patients. Mesenteric panniculitis of the colon seems to be a lesion more advaced than the same condition of the small intestine, and colostomy or bypass surgery may be needed for alleviation of severe symptoms.  相似文献   
997.
To accurately select patients with malignant colorectal polyps who are at high risk of adverse outcome, we examined the predictive value of clinicopathological factors, with special attention paid to the histology at the invasive margin. We examined 75 submucosal carcinomas from 75 patients, initially resected by polypectomy, including endoscopic, trans-anal, trans-sacral, and trans-sphincteric local excision. The associations between clinicopathological features such as sex and age; tumor size, location, shape, depth of submucosal invasion, vascular invasion, histology at the central part, and histology at the invasive margin; and the presence or absence of a residual adenomatous component and adverse outcome were examined by univariate and multivariate logistic regression analyses. Lymph node metastases were found in 2 patients, local recurrence in 4, and distant metastases in 2. Univariate logistic regression analysis showed that unfavorable histology at the invasive margin was significantly associated with lymph node metastasis or local recurrence (P = 0.0373), whereas the association of lymphatic invasion and vascular (lymphatic or venous) invasion with lymph node metastasis or local recurrence had marginal significance (P = 0.0785; P = 0.0990). Multivariate logistic regression analysis, with unfavorable histology at the invasive margin and lymphatic invasion as independent variables, showed that unfavorable histology alone had significance (P = 0.0373) in predicting adverse outcome. Widely accepted criteria such as massive submucosal invasion, positive vascular invasion, and poorly differentiated histology, were less useful in predicting adverse outcome. These results suggest that unfavorable histology at the invasive margin is a useful risk factor for predicting lymph node metastasis or local recurrence in patients with malignant colorectal polyps. Received: March 23, 1999 / Accepted: August 27, 1999  相似文献   
998.
We report on a 22-year-old man with congenital hypogammaglobulinemia who developed multiple colorectal neoplasms. An immunodeficiency had been diagnosed in the patient since two years of age, and this time many tumors of the sigmoid colon and rectum were detected by barium enema and fiberscopy. Abdominoperineal resection was performed, and the resected specimen revealed 29 polyps, including 9 adenocarcinomas and 20 adenomas. The carcinomas, measuring 0.8 to 11.0 cm in size, showed various depths of invasion, and the adenomas, measuring 0.2 to 1.5 cm in size, showed various degrees of epithelial atypia. DNA analysis demonstrated that the tumors were heterogeneous, showing different DNA index and ploidy patterns. The pathogenetic relation between malignancy and immunodeficiency is also reviewed.  相似文献   
999.
Clostridium infections are rare but frequently associated with malignancy, and mortality approaches 100% if care is not rendered within 12 to 24 h. These infections are associated with various medical problems including diabetes mellitus. In this report, we describe a unique case of sepsis and a gas-forming splenic abscess caused by Clostridium septicum in a type 2 diabetes patient which was treatable solely with antibiotics.  相似文献   
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