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991.
Laparoscopic cholecystectomy (LC) for gallstones has become a popular treatment modality, but LC for gallbladder cancer is not yet established and its prognosis is still unknown. We clinicopathologically studied unsupected gallbladder cancer presenting at pathologic evaluation after LC. The entire cross section of gallbladders after 456 LCs was histologically examined. The presence of malignant lesions was confirmed in 13 (2.85%) of 456 cases. The preoperative diagnoses were gallstones in 5 patients, gallbladder polyps in 5, gallstones with gallbladder polyps in 2, and gallstones with adenomyomatosis in 1. The carcinoma had invaded the mucosa in 7, the proper muscle in 2, and the subserosa in 3; the serosa was exposed in 1. The tumor size ranged from 2 mm to the entire gallbladder. An additional resection was performed in 2 patients. During the mean follow-up period of 25.9 months, 1 patient died of recurrence at 8 months while 1 demonstrated recurrence at the port site 1 year after surgery. No other patients have had any recurrence to date. Since early gallbladder cancer removed laparoscopically can be expected to have a satisfactory outcome, diagnostic and therapeutic LC is recommended in cases where total biopsy is indicate. However, in every case, extreme caution needs to be exercised to prevent the dissemination and implantation of cancer cells at the port site. Portions of this paper were presented in 1995 at the 36th World Congress of Surgery in Lisbon, Portugal.  相似文献   
992.
Mice with short and knotty tails arose as a spontaneous mutant in an ICR strain, and they have been named knotty-tail mouse (gene symbol; knt). They also have a minor anomaly of the cervical vertebrae, especially in the axis. In this study, the cervical vertebrae of knotty-tail (knt/knt) mice were investigated by morphological and morphometric examinations during the prenatal and postnatal period. From the observation of double-stained preparations of knt/knt mice, morphological changes of cervical vertebrae were confined to the vertebral arch of the axis, which was asymmetrical and hypoplastic. From the morphometric analyses, outside of the axis, minor anomalies (i. e., broadened cervical vertebrae in the transverse direction, shortened and broadened ventral tuberculum of the atlas, thickened ventral lamina of 6th cervical vertebra) were maintained in the cervical vertebrae of knt/knt mice. Morphological deformity, reflecting an adult osseous anomaly, had been already formed in the cartilaginous axis prenatally. In the papain-digested preparations of knt/knt mice, a bony invagination into the canal was detected in the axis, and the morphometric analyses on axis revealed that the growth of spinous process was apparently disturbed in comparison with that of ICR mice.  相似文献   
993.
The authors describe a case in which a biliary-hepatic artery fistula was created by a glidewire perforation during percutaneous transhepatic biliary drainage and was successfully treated by embolization via the transbiliary tract. Great caution should be exercised to avoid perforation when a Terumo hydrophilic glidewire is used during biliary intervention.  相似文献   
994.
Dimethyl sulfoxide (DMSO) exerts a number of biological effects including the promotion of cell differentiation in cultured cells. In this study, we examined the effect of DMSO on the adhesion of tumor cells to endothelial cells. In vitro treatment of human gastric adenocarcinoma (NUGC4) cells with DMSO resulted in increased adhesion to interleukin-1 (IL-l)-activated human endothelial cells compared with DMSO-untreated NUGC4 cells. In flow cytometry, treating NUGC4 cells with DMSO enhanced the expression of sialyl Lewis x (sialyl Lex) and sialyl dimeric Lex antigens on their surface. Also, the binding of Limulus polyphemus agglutinin (LPA), which specifically binds to cell-surface sialic acids, was increased by DMSO. The adhesion of DMSO-treated NUGC4 cells to activated endothelial cells was blocked by neuraminidase pre-treatment of tumor cells or by antibody against either endothelial leukocyte adhesion molecule-1 (ELAM-I) or sialyl Lex. Thus, it is suggested that enhanced adhesion following DMSO treatment is mediated by the interaction of sialyl Lex expressed on NUGC4 cells with ELAM-I of endothelial cells. The modulation of sialyl Lex antigen by DMSO provides a useful system for studying the regulatory mechanism of Lewis-related carbohydrate antigens and also for understanding the metastatic properties of cancer cells.  相似文献   
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Both constipation and fecal incontinence are prominent lower gastrointestinal tract (LGIT) dysfunctions that occur frequently in multiple system atrophy (MSA). We investigated the mechanism of constipation and fecal incontinence in MSA. Colonic transit time (CTT), sphincter electromyography (EMG), and rectoanal videomanometry were performed in 15 patients with MSA (10 men, 5 women; mean age, 63.5 years; mean duration of disease, 3 years; decreased bowel frequency [< 3 times a week] in 9; difficulty in expulsion in 11; fecal incontinence in 3) and 10 age-matched healthy control subjects (7 men and 3 women; mean age, 62 years; decreased bowel frequency in 2; mild difficulty in expulsion in 2; fecal incontinence in none). Compared to the control subjects, MSA patients had significantly prolonged CTT in the rectosigmoid segment and total colon. Sphincter EMG showed neurogenic motor unit potentials in none of control subjects but in 93% of MSA patients. At the resting state, MSA patients showed a lower anal squeeze pressure (external sphincter weakness) and a smaller increase in abdominal pressure on coughing. During rectal filling, MSA patients showed smaller amplitude in phasic rectal contraction, which was accompanied by an increase in anal pressure that normally decreased, together with leaking in 3 patients. During defecation, most MSA patients could not defecate completely and had larger postdefecation residuals. MSA patients had weak abdominal strain, smaller rectal contraction on defecation, and larger anal contraction on defecation (paradoxical sphincter contraction on defecation), although these differences were not statistically significant. These findings in MSA patients were similar to those in Parkinson's disease patients in our previous study, except for the sphincter denervation and weakness in MSA. Constipation in MSA most probably results from slow colonic transit, decreased phasic rectal contraction, and weak abdominal strain, and fecal incontinence results from weak anal sphincter due to denervation. The responsible sites for these dysfunctions seem to be both central and peripheral nervous systems that regulate the LGIT.  相似文献   
999.
Nineteen patients (20 operations) underwent elective carotid endarterectomy without arterial shunt. Carotid cross-clamping caused a significant decrease (from 61.2% to 49.5%, 19.1% decrease from the preclamp baseline) of the ipsilateral cerebral oxygen saturation and it increased to 65.6% after declamping. Cross-clamping also caused a significant decrease (from 2.9 Hz to 1.6 Hz) of the ipsilateral electroencephalogram main frequency and it increased to 3.6 Hz after declamping. Asymmetry of main frequency which was greater than 0.7 Hz was observed when that of oxygen saturation decreased more than 25% during cross-clamping. The reported data indicate that cerebral oxygen saturation less than 54-56.1% and its decrease more than 15.6-18.2% is found to be a predictor of neurologic compromise. In this study, the asymmetry of cerebral oxygen saturation more than 25% was also found to be a risk. Arterial shunt should be used in haemodynamically high risk cases.  相似文献   
1000.
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