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81.
Abstract. Background/Purpose: Although curative surgical resection provides the best chance of long-term survival for patients with intrahepatic cholangiocarcinoma, the presence of bile duct invasion decreases postoperative survival rates in patients with mass-forming intrahepatic cholangiocarcinoma. We carried out this study to determine a surgical strategy for patients with bile duct invasion of these tumors. Methods: Forty-one patients with mass-forming intrahepatic cholangiocarcinoma were classified as either having bile duct invasion (n= 26) or not having bile duct invasion (n= 15). Clinicopathologic findings, including postoperative outcomes, were compared between these two groups. Results: Perineural invasion, lymphatic invasion, and a positive resection margin were more frequent in patients with ductal invasion. Patients with ductal invasion had lower survival rates than those without ductal invasion. Conclusions: Intraoperative frozen section examination of the bile duct stump to confirm a clear resection margin is required in patients with mass-forming tumors. Resection of the extrahepatic bile duct should be considered when tumor cells are identified at the surgical margin of the resected bile duct. Received: October 30, 2001 / accepted: November 16, 2001  相似文献   
82.
 The aim of this study was to clarify the relationship between endogenous estrogen, sex hormone-binding globulin (SHBG), and bone loss in pre-, peri-, and postmenopausal female residents of Taiji, a rural Japanese community. From a list of inhabitants aged 40 to 79 years, 200 participants—50 women in each of four age decades—were randomly selected, and baseline bone mineral density (BMD) at the lumbar spine and proximal femur were measured by dual-energy X-ray absorptiometry in 1993. Total estradiol (total E2) and SHBG were measured, and SHBG-unbound E2 (UBE2) was calculated using SHBG and the percent SHBG-unbound fraction ratio. BMD was measured again 3 years later, in 1996. Participants with ovariectomy or hysterectomy were excluded, and the remaining participants were categorized into four groups: premenopausal (n= 38), perimenopausal (n= 14), postmenopausal group 1 (5 years or less since menopause; n= 18), and postmenopausal group 2 (6 years or more since menopause; n= 74). The mean value of total E2 was highest in the premenopausal group (49.1 pg/ml), followed by the perimenopausal group (26.4 pg/ml), and the postmenopausal groups (0.83 pg/ml in postmenopausal group 1 and 0.96 pg/ml in postmenopausal group 2). The means for UBE2 showed the same pattern across the groups. After the multiple regression analysis of BMD at follow-up and endogenous estrogens, in premenopausal women, there were no significant associations between BMD at follow-up and serum total E2 and UBE2. In perimenopausal women, however, serum total E2 and UBE2 were significantly correlated with trochanteric BMD at follow-up (P < 0.05); and in postmenopausal group 2, they were significantly correlated with lumbar spine and Ward's triangle BMD at follow-up (P < 0.001 at lumbar spine, P < 0.05 at Ward's triangle). Concerning the association between BMD at follow-up and SHBG, in the premenopausal group, serum levels of SHBG were negatively correlated with BMD at the femoral neck (P < 0.05). In regard to partial regression coefficients for the change rates of BMD over 3 years and serum estrogens and SHBG concentrations, in perimenopausal women, UBE2 was correlated with the change rate of BMD at Ward's triangle (P < 0.05), and in postmenopausal group 1, serum levels of SHBG were significantly negatively related to change in BMD at the trochanter (P < 0.01). No other relationships with change in BMD were observed at any sites. These findings suggest that serum E2, UBE2, and SHBG levels differentially predict BMD levels in groups of differing menstrual status. It would, however, be difficult to predict bone loss in middle-aged and elderly Japanese women over a 3-year period using these indices alone. Received: November 29, 2001 / Accepted: February 28, 2002  相似文献   
83.

Background and Aims

Endoscopic submucosal dissection (ESD) has recently been applied to the treatment of superficial colorectal cancer. Clinical outcomes compared with conventional endoscopic mucosal resection (EMR) have not been determined so our aim was to compare the effectiveness of ESD with conventional EMR for colorectal tumors ≥20 mm.

Methods

This was a retrospective case-controlled study performed at the National Cancer Center Hospital in Tokyo, Japan involving 373 colorectal tumors ≥20 mm determined histologically to be curative resections. Data acquisition was from a prospectively completed database. We evaluated histology, tumor size, procedure time, en bloc resection rate, recurrence rate, and associated complications for both the ESD and EMR groups.

Results

A total of 145 colorectal tumors were treated by ESD and another 228 were treated by EMR. ESD was associated with a longer procedure time (108 ± 71 min/29 ± 25 min; p < 0.0001), higher en bloc resection rate (84%/33%; p < 0.0001) and larger resected specimens (37 ± 14 mm/28 ± 8 mm; p = 0.0006), but involved a similar percentage of cancers (69%/66%; p = NS). There were three (2%) recurrences in the ESD group and 33 (14%) in the EMR group requiring additional EMR (p < 0.0001). The perforation rate was 6.2% (9) in the ESD group and 1.3% (3) in the EMR group (p = NS) with delayed bleeding occurring in 1.4% (2) and 3.1% (7) of the procedures (p = NS), respectively, as all complications were effectively treated endoscopically.

Conclusions

Despite its longer procedure time and higher perforation rate, ESD resulted in higher en bloc resection and curative rates compared with EMR and all ESD perforations were successfully managed by conservative endoscopic treatment.  相似文献   
84.
We report a case of sporadic gastric carcinoid tumor successfully treated by two-stage laparoscopic surgery. A 38-year old asymptomatic woman was referred to our hospital for evaluation of a submucosal tumor of the stomach. Endoscopic examination showed a solitary submucosal tumor without ulceration or central depression on the posterior wall of the antrum and biopsy specimens were not sufficient to determine the diagnosis. Endoscopic ultrasound revealed a tumor nearly 2 cm in diameter arising from the muscle layer and a computed tomography scan showed the tumor enhanced in the arterial phase. Laparoscopic wedge resection was performed for definitive diagnosis. Pathologically, the tumor was shown to be gastric carcinoid infiltrating the muscle layer which indicated the probability of lymph node metastasis. Serum gastrin levels were normal. As a radical treatment, laparoscopy-assisted distal gastrectomy with regional lymphadenectomy was performed 3 wk after the initial surgery. Finally, pathological examination revealed no lymph node metastasis.  相似文献   
85.
A 62-year-old man presented with a giant tumor in the pelvic cavity that was incidentally revealed by abdominal ultrasonography. Abdominal magnetic resonance imaging showed the heterogenous tumor in the pelvis with cystic components. The tumor was 10.8 × 10.5 × 11.7 cm in diameter and adhered to the sacral wall. The tumor was extirpated following diagnosis as a benign neurogenic tumor by needle biopsy. The pelvic cavity was occupied by the tumor rigidly adhered to the sacrum. The histopathological diagnosis of the specimen was benign schwannoma, type Antoni A.  相似文献   
86.
We have investigated the efficacy of immunization against peptides from predisposing MHC class II molecules in human-compatible adjuvants for ameliorating experimental autoimmune myasthenia gravis (EAMG). C57BL/6 mice were immunized three times with the peptide I-Abetab62-76 in Alum+killed pertussis organisms (PT) prior to two injections with tAChR. The treatment greatly reduced the occurrence and severity of clinical MG relative to controls that received saline/Alum+PT or none. It also reduced antibody and T-cell responses against tAChR. The results have important implications for the possible immunotherapy of MG by targeting disease-associated MHC.  相似文献   
87.
We report a 53-year-old woman with severe Graves' ophthalmopathy accompanied by uncontrolled myasthenia gravis. She presented remarkable exophthalmos, chemosis, and restriction of eye movement. Despite plasma exchange, steroid pulse therapy, local injection of steroid, and irradiation, ocular symptoms did not ameliorate. Since optic neuropathy was seen, orbital decompression surgery was performed in the left eye. Bilateral chemosis was improved after the surgery. Five years after surgery, there was no ocular palsy in the operated left eye, but in the contralateral eye. For the good prognosis of the eye movement, orbital decompression might be recommended in the severe Graves' ophthalmopathy accompanied by the optic neuropathy and/or ophthalmoplegia with proptosis.  相似文献   
88.
Objectives: It has been reported that kidney stones are linked to metabolic syndrome (MetS), which is characterized by insulin resistance. The aim of the present study was to examine the association of insulin resistance, insulin and adiponectin with kidney stones in a Japanese population. Methods: From February 2007 to March 2008, 1036 (529 men and 507 women) apparently healthy Japanese subjects, aged 35–79 years, were analyzed. Weight, height, waist circumference and blood pressure were measured. Overnight fasting blood was collected to measure insulin and adiponectin levels. Homeostasis model assessment of insulin resistance (HOMA‐IR) was calculated to assess insulin resistance. Logistic regression analysis was used to estimate the odds ratio (OR) and 95% confidence intervals for a self‐reported history of kidney stones across tertiles of HOMA‐IR, insulin and adiponectin. Results: Of the participants, 84 men (15.6%) and 35 women (6.9%) had a history of kidney stones. Age, body mass index, waist circumference, systolic and diastolic blood pressures, HOMA‐IR and insulin were significantly higher in women with than in women without kidney stones. There was no difference in adiponectin level between subjects with and without a history of kidney stones in either sex. Furthermore, a significant positive trend was observed in the age‐adjusted OR for a history of kidney stones across insulin tertiles (P‐value for trend = 0.04) in women. Conclusions: For Japanese women, HOMA‐IR and insulin are associated with a history of kidney stones. The findings suggest that MetS components could increase the risk of kidney stones through subclinical hyperinsulinemia and insulin resistance.  相似文献   
89.
Although an ascending aortic thrombus is a rare finding, it may cause major embolic complications. We report a case of a 58-year-old male who suffered from cerebral and left renal infarctions due to emboli from a giant thrombus in the ascending aorta. The thrombus was demonstrated by computed tomography and transesophageal echocardiography. Ten days after the initiation of anticoagulation therapy, surgery was performed. After a median sternotomy was performed and cardiopulmonary bypass was initiated, the ascending aorta was replaced with a synthetic graft under hypothermic circulatory arrest and retrograde cerebral perfusion. The excised specimen revealed a 3.5×3.0×3.0-cm pedunculated thrombus. The patient's postoperative recovery was uneventful, and there was no recurrence of aortic thrombosis during one year of postoperative follow-up. The patient had no coagulation disorders, and the etiology of this giant thrombus remains unclear. We believe that initial treatment for an ascending aortic thrombus should be emergency surgery before it leads to major embolic events. However, the treatment strategy for a thrombus causing cerebral infarction is sometimes difficult to develop.  相似文献   
90.
Osteoclasts form ruffled borders and sealing zones toward bone surfaces to resorb bone. Sealing zones are defined as ringed structures of F-actin dots (actin rings). Polarized osteoclasts secrete protons to bone surfaces via vacuolar proton ATPase through ruffled borders. Catabolic enzymes such as tartrate-resistant acid phosphatase (TRAP) and cathepsin K are also secreted to bone surfaces. Here we show a simple method of identifying functional vestiges of polarized osteoclasts. Osteoclasts obtained from cocultures of mouse osteoblasts and bone marrow cells were cultured for 48 h on dentin slices. Cultures were then fixed and stained for TRAP to identify osteoclasts on the slices. Cells were removed from the slices with cotton swabs, and the slices subjected to TRAP and Mayer's hematoxylin staining. Small TRAP-positive spots (TRAP-marks) were detected in the resorption pits stained with Mayer's hematoxylin. Pitted areas were not always located in the places of osteoclasts, but osteoclasts existed on all TRAP-marks. A time course experiment showed that the number of TRAP-marks was maintained, while the number of resorption pits increased with the culture period. The position of actin rings formed in osteoclasts corresponded to that of TRAP-marks on dentin slices. Immunostaining of dentin slices showed that both cathepsin K and vacuolar proton ATPase were colocalized with the TRAP-marks. Treatment of osteoclast cultures with alendronate, a bisphosphonate, suppressed the formation of TRAP-marks and resorption pits without affecting the cell viability. Calcitonin induced the disappearance of both actin rings and TRAP-marks in osteoclast cultures. These results suggest that TRAP-marks are vestiges of proteins secreted by polarized osteoclasts.  相似文献   
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