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131.
Here, we describe a simple in vitro neural crest cell (NCC) migration assay and the effects of all‐trans‐retinoic acid (RA) on NCCs. Neural tubes excised from the rhombencephalic or trunk region of day 10.5 rat embryos were cultured for 48 h to allow emigration and migration of NCCs. Migration of NCCs was measured as the change in the radius (radius ratio) calculated from the circular spread of NCCs between 24 and 48 h of culture. RA was added to the culture medium after 24 h at embryotoxic concentrations determined by rat whole embryo culture. RA (10 μM) reduced the migration of cephalic NCCs, whereas it enhanced the migration of trunk NCCs, indicating that RA has opposite effects on these two types of NCCs.  相似文献   
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This is the first case report of Hodgkin's disease (HD) which showed both remission and exacerbation of neurological signs before a confirmed diagnosis of HD. The episodes occurred three times and multiple lesions were involved. Immunoabsorption plasmapheresis and double filtration plasmapheresis were effective for the first episode, whereas, corticosteroids partly improved the second and third episodes. Fever and lymph node swelling were apparent afterward and she was diagnosed as having HD from a supraclavicular lymph node biopsy. The remaining neurologic deficits responded to chemotherapy and radiotherapy. The neurological symptoms were considered as a paraneoplastic syndrome of HD.  相似文献   
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BACKGROUND: Several preliminary studies have indicated that atrial pacing can prevent atrial tachyarrhythmias. The suggested mechanisms by which pacing may be effective include suppression of premature atrial beats. METHODS AND RESULTS: The Atrial Pacing Preference (APP; Guidant, St Paul, MN, USA) algorithm allows the pacemaker to maintain a pacing rate slightly higher than the sinus rate. The preventive effects of APP on paroxysmal atrial fibrillation (AF) were studied in 51 patients (70+/-11 years). Nine patients did not complete the protocol. The pacemaker was programmed in random order to APP off and APP on at 3 different settings (ie, 8, 16 and 32 cycles) for 4 weeks each, using a cross-over design. Percentage atrial pacing was lower in APP off than at the other settings. Premature beat counts were greater in APP off than at the other settings. There was a significant difference in mode switch episode counts between APP off and the most effective setting (3,818+/-15,356 vs 596+/-1,719; p<0.01). CONCLUSIONS: The APP algorithm is a promising method for preventing atrial tachyarrhythmia in patients with an implanted pacemaker and AF. Optimizing the setting of the APP algorithm is an important issue in the prevention of AF.  相似文献   
137.
To examine the prevalence of and risk factors for low bone mineral density (BMD) (osteoporosis or osteopenia) in Japanese female patients with systemic lupus erythematosus (SLE). We performed BMD measurements by dual X-ray absorptiometry at the lumbar spine and the hip and collected basic and lifestyle-related, clinical and treatment characteristics among 58 SLE patients. Odds ratios (ORs) and their 95% confidence intervals (CIs) were assessed for associations between low BMD and selected factors among SLE patients. The mean BMD?±?SD was 0.90?±?0.17?g/cm2 at the lumbar spine and 0.76?±?0.17?g/cm2 at the hip. The prevalence of osteopenia (2.5 SD?<?T score?<?1 SD) was 50.0% and that of osteoporosis (T score?<?2.5 SD) was 13.8% in our SLE patients. After adjustment for age and disease duration, we found the number of deliveries (OR?=?5.58, 95% CI?=?1.31?C26.06; P?=?0.02) to be a risk factor for overall low BMD (T score?<?1 SD) and a maximal dosage of >50?mg/day of oral corticosteroids (OR?=?0.25, 95% CI?=?0.07?C0.91; P?=?0.035) as a preventive factor for low BMD at the lumbar spine. Reduced BMD, especially in spinal trabecular bone, was pronounced in Japanese female patients with SLE, particular in those with a history of delivery. A history of high-dose oral corticosteroids was associated with the preservation of BMD at the lumbar spine, however, further study is needed considering the limited sample size.  相似文献   
138.
The basic region–leucine zipper (bZip) factor BTB, CNC homology 2 (BACH2) is known to have important roles in class switch recombination and somatic hypermutation (SHM) of the immunoglobulin (Ig) gene. In this study, we investigated the relationship between the expression of BACH2 and the status of SHM of the Ig heavy chain gene variable region (IgHV) for SHM in diffuse large B‐cell lymphoma (DLBCL). We examined 20 cases of DLBCL, 13 of which were germinal center B‐cell (GCB) DLBCL and 7 were non‐GCB DLBCL. Seven cases were negative, 6 were positive (cytoplasmic expression) and 7 were strongly positive (both nuclear and cytoplasmic expression) for BACH2. Confirmed mutation (CM) was identified in 8 cases and the CM index (number of confirmed mutations per 10 subclones) was distributed from 0 to 5. A CM index of 7 strongly positive (over‐expression) cases with BACH2 were distributed from 0 to 5, and that of 7 negative and 6 positive cases were distributed from 0 to 1. Over‐expression of BACH2 was statistically related to CM index (P = 0.008). In conclusion, over‐expression of BACH2 is critical for ongoing SHM of IgHV in DLBCL, and our data suggest that BACH2 may play an essential role for SHM of the Ig gene in B‐cell lymphoma.  相似文献   
139.
First-degree relatives of persons with thyroid cancer are known to be at relatively high risk for the disease. To better understand the clinicopathologic characteristics of familial nonmedullary thyroid carcinoma (FNMTC), we carried out a retrospective study in which we identified individuals treated at our institution who had at least one first-degree relative with the disease. We used data obtained from our patient records to compare the features of 258 cases of the disease with the features of sporadic papillary or follicular thyroid carcinoma in another group of patients. The 258 patients represented 154 families and were selected from among 6458 patients with papillary or follicular thyroid carcinoma who underwent thyroidectomy between 1946 and 2000. Compared to the patients with sporadic disease, the FNMTC patients were more likely to have intraglandular dissemination (28.5% vs. 40.7%; p < 0.0001) and multiple benign nodules (29.8% vs. 41.5%; p <0.0001). There were no significant differences between the two types of patients in terms of gender, age, tumor diameter, adhesion to or invasion of the surrounding tissues, macroscopic metastasis observed at surgery, histology, presence of single benign nodules, presence of chronic thyroiditis, microscopic metastasis, or rate of lymph node metastasis. Recurrence was statistically frequent in the FNMTC patients compared with that in the sporadic disease patients (16.3% vs. 9.6%; p = 0.0005), and the disease-free survival rate was significantly poorer in the FNMTC patients (p = 0.0041 by the Wilcoxon test and p <0.0001 by the log-rank test). No significant difference in the overall survival rate was found between the two groups. Multivariate analysis by Cox’s proportional hazards method showed FNMTC to be an independent predictor of shorter disease-free survival (risk ratio 1.88; confidence interval 1.35–2.54; p = 0.0003). Locoregional recurrence in the ipsilateral or contralateral lymph nodes and contralateral thyroid lobe was significantly more frequent in the FNMTC patients than in the sporadic disease patients, whereas no difference was found regarding distant metastases. We conclude that FNMTC is a clinically distinct entity with an aggressive nature. Because of the frequent presence of benign nodules, multifocality, and high rate of locoregional recurrence, total or near-total thyroidectomy with modified radical neck dissection in FNMTC patients is recommended.  相似文献   
140.
BACKGROUND: Use of the inferior mesenteric vein (IMV) for partial portal decompression has not been recommended as a first-line option for intractable gastroesophageal variceal bleeding because of the thin diameter of the vein. Although these indications remain relevant, few reports have compared partial portal decompression using the IMV with other therapies. We propose that partial portal decompression using the IMV is a useful alternative treatment for intractable variceal bleeding. METHODS: We performed partial portal decompression using the IMV in eight patients with intractable variceal bleeding that had been uncontrolled using medical and endoscopic therapies. All patients were classified into Child's class B or C. The surgical data, morbidity, and mortality were assessed. RESULTS: Mean portal venous pressure significantly decreased from 26.9 +/- 2.0 mmHg before the surgery to 19.8 +/- 3.9 mmHg after the surgery. The operative mortality rate was 0%. The mean duration of hospital stay was 25.5 +/- 13.3 days. Although one patient experienced recurrent bleeding, shunt patency was well maintained in all patients during the follow-up period (mean 28.9 +/- 14.1 months). Six patients are still alive and well without ascites or hepatic encephalopathy. Two of the Child's class C patients who underwent emergency shunt died owing to hepatic decompensation. CONCLUSION: Partial portal decompression using the IMV can be a safe, effective way to treat intractable variceal bleeding in patients with liver cirrhosis. However, use of the shunt procedure may have the most survival benefits for cirrhotic patients with preserved liver function.  相似文献   
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