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991.
Benign schwannomas arise in neural crest-derived Schwann cells. They can occur almost anywhere in the body, but their most common locations are the central nervous system, extremities, neck, mediastinum, and retroperitoneum. Schwannomas occurring in the biliary tract are extremely rare and mostly present with obstructive jaundice. We recently experienced a case of extrahepatic biliary schwannomas in a 64-yr-old female patient who presented with intra- and extrahepatic bile duct and gallbladder stones during a screening program. To the best of our knowledge, extrahepatic biliary schwannomas associated with bile duct stones have not been reported previously in the literature.  相似文献   
992.
We report a case of 61-yr-old man with stable psoriasis who progressively developed generalized pustular eruption, erythroderma, fever, and hepatic dysfunction following oral terbinafine. Skin biopsy was compatible with pustular psoriasis. After discontinuation of terbinafine and initiating topical corticosteroid and calcipotriol combination with narrow band ultraviolet B therapy, patient's condition slowly improved until complete remission was reached 2 weeks later. The diagnosis of generalized pustular psoriasis (GPP) induced by oral terbinafine was made. To our knowledge, this is the first report of GPP accompanied by hepatic dysfunction associated with oral terbinafine therapy.  相似文献   
993.
994.
B cell receptor (BCR) signaling plays a critical role in B cell tolerance and activation. Here, we show that mice with B cell-specific ablation of both Cbl and Cbl-b (Cbl-/-Cblb-/-) manifested systemic lupus erythematosus (SLE)-like autoimmune disease. The Cbl double deficiency resulted in a substantial increase in marginal zone (MZ) and B1 B cells. The mutant B cells were not hyperresponsive in terms of proliferation and antibody production upon BCR stimulation; however, B cell anergy to protein antigen appeared to be impaired. Concomitantly, BCR-proximal signaling, including tyrosine phosphorylation of Syk tyrosine kinase, Phospholipase C-gamma2 (PLC-gamma2), and Rho-family GTP-GDP exchange factor Vav, and Ca2+ mobilization were enhanced, whereas tyrosine phosphorylation of adaptor protein BLNK was substantially attenuated in the mutant B cells. These results suggested that the loss of coordination between these pathways was responsible for the impaired B cell tolerance induction. Thus, Cbl proteins control B cell-intrinsic checkpoint of immune tolerance, possibly through coordinating multiple BCR-proximal signaling pathways during anergy induction.  相似文献   
995.
996.

Introduction

Intestinal failure–associated liver disease (IFALD) occurs commonly in intestinal transplant (ITx) candidates receiving parenteral nutrition (PN). The aim of this study is to establish the prevalence and risk factors for advanced liver fibrosis in adults at the time of ITx.

Methods

Retrospective chart review of all ITx was performed in adults between January 2000 and May 2014. Advanced liver fibrosis was defined as stage 3 or stage 4 fibrosis.

Results

Fifty‐three patients met the inclusion criteria. The mean age was 50.6 ± 10.9 years, and the majority were female (60.4%) and Caucasian (67.9%). The mean body mass index was 21.7 ± 3.8 kg/m2 and the median duration of PN was 402 (interquartile range: 529) days. Advanced liver fibrosis at the time of ITx was found in 13 patients (24.5%). The multivariate analysis revealed that female gender and white race were significant predictors of advanced liver fibrosis. A total bilirubin >3.0 mg/dL for > a month prior to ITx was associated with an odds ratio of 8.9 for advanced fibrosis at the time of ITx but did not reach statistical significance (P = 0.055).

Conclusion

Close to one‐quarter of the ITx recipients had advanced liver fibrosis. In the current era of improved PN management, our data suggests that previously reported risk factors for IFALD, such as extreme short gut syndrome and PN duration, may have a lesser impact on development of liver fibrosis. A prolonged duration of bilirubin elevation may be associated with advanced liver fibrosis in patients with IFALD, but this requires validation in a larger cohort.  相似文献   
997.
Despite significant efforts to develop micropumps, cumbersome driving equipment means that the design of portable micropumps remains a challenge. This study presents a stand-alone micropump system, which includes a peristaltic micropump based on piezoelectric actuation and a driving circuit. This battery-based driving circuit comprises a 12 V battery, an ATmega 8535 microprocessor, a 12 V-to-180 V DC to DC converter using transformerless technology, three differential amplifiers, an IC 7805, a phase controller, an A/D converter, a keyboard and an LCD module. The system can produce step-function signals with voltages of up to 228 Vpp and frequencies ranging from 10 Hz to 100 kHz, as the inputs for the pump. It is portable and programmable with the package size of 22 × 12.8 × 9 cm. Additionally, this proposed system is used to design the driving signals of the pump which are 3-, 4, and 6-phase actuation sequences. This work performs the circuit testing and fluid pumping, and demonstrates the effects of actuation sequences on pump performance in terms of the dynamic behavior of the diaphragm, flow rates, back pressure and power consumption of the system. The experimental results show that the pump excited by the 6-phase sequence results in better performance compared with the 3- and 4-phase sequences, and produces a maximum flow rate of 36.8 μl/min and a maximum back pressure of 520 Pa with deionized water at 100 V pp and 700 Hz.  相似文献   
998.
OBJECTIVE: The objective of this study was to characterize the familial associations of symptoms or symptom dimensions of schizophrenia, as a component of the effort to delineate suitable phenotypic markers under the homogenous genetic control. METHODS: Clinical symptoms of the patients were evaluated on a lifetime basis, with the Korean version of the Diagnostic Interview for Genetic Studies and the Krawieka scale. Our sample consisted of 54 sibling pairs who were concordant for Diagnostic and statistical manual of mental disorder-IV schizophrenia or schizoaffective disorder. RESULTS: At the individual symptom level measured by the Diagnostic Interview for Genetic Studies, we observed a statistically significant degree of concordance within the sibling pairs for auditory hallucination (kappa=0.600, chi(2)=15.193, P=0.000). The within-sibling resemblance of this symptom was also indicated by the results of correlation analyses of individual items of the Krawiecka scale (partial correlation coefficient=0.423, P=0.005). Among the individual symptoms or symptom dimensions of the Krawiecka scale, the 'anxious' (partial correlation coefficient=0.469, P=0.001) and the 'affective dimension' (including the items of 'anxious' and 'depressed') (partial correlation coefficient=0.436, P=0.003) were also determined to indicate significant intra-pair correlations after controlling for potential confounding variables, such as sex, duration of illness, and age of onset. CONCLUSIONS: The results of this study suggest that familial factors, possibly genetic factors, contribute a liability to the development of auditory hallucinations. This symptom might then prove useful as a phenotype marker in future genetic studies.  相似文献   
999.
Ji JH  Shafi M  Kim WY  Park SH  Cheon JO 《The Knee》2007,14(3):249-252
We report a case of Baker's cyst that induced compression of both the tibial and common peroneal nerves. The patient presented with calf atrophy and foot drop over a 6-month period. These signs and symptoms could have been mistaken for those of spinal origin. Based on an electrodiagnostic study and magnetic resonance imaging, compression of nerves by an asymptomatic Baker's cyst measuring 6x4 cm was confirmed. This cyst communicated with the articular joint which was also associated with a medial meniscal lesion. We treated the patient arthroscopically by performing partial medial meniscectomy, and through the posterolateral and the posteromedial portal, decompression of the Baker's cyst was performed. Approximately 6 weeks after the arthroscopic decompression, the cyst recurred. Therefore open resection was performed. At 1-year follow-up, the patient had considerable improvement in motor as well as sensory function and showed no evidence of recurrence. Although the electrodiagnostic studies showed an improvement in symptoms, the patient continued to complain of lower leg weakness owing to delayed diagnosis and cyst decompression. We believe that Baker's cysts should also be considered in the differential diagnoses of patients who present with neuromuscular dysfunction in the calf and leg.  相似文献   
1000.
Introduction: This study aimed to evaluate the six-month incidence and possible risk factors of neck discomfort among sedentary workers. Methods: Data, including demographic characteristics, work history, psychological characteristics and prevalent neck discomfort of 157 sedentary workers was collected by a questionnaire. A follow-up questionnaire was administered six months later to calculate the incidence of symptoms and related disability. Results: The six-month incidence of neck discomfort was 23.5% (12/51). The two groups of prevalent and non-prevalent subjects showed no difference in demographic data and work characteristics except for work load (p<0.05) and score in “job control” in the Job Content Questionnaire (JCQ) (p<0.05). In logistic regression, light-load work (versus no-load work, OR = 0.10, p = 0.023) and higher score of ‘job control’ in JCQ (OR = 0.86, p = 0.031) were significant protecting factors. Conclusion: The six-month incidence rates of neck discomfort in our subjects were high. Light-load work and a higher score of ‘job control’ were important preventive factors. The results provide an epidemiological basis for prevention of neck discomfort in different working populations.  相似文献   
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