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941.
942.
943.
We performed thoracoscopic resection of a middle mediastinal noninvasive thymoma in a 69-year-old woman. Chest computed tomography on admission showed a tumor, 75 x 48 x 32 mm in size, and pathological examination revealed a spindle-cell, noninvasive thymoma, of type A according to the World Health Organization classification, and stage I according to the Masaoka staging system. Thymomas are prone to ectopic occurrence, and should be considered in the differential diagnosis of middle mediastinum tumors.  相似文献   
944.
PURPOSE: Antimuscarinic drugs increase bladder capacity without prominent side effects such as urinary retention even when administered to patients with mild to moderate bladder outlet obstruction. Some mechanisms might exist in the urethra to compensate for the emptying function of the detrusor after the administration of antimuscarinic drugs. We investigated the influence of the antimuscarinic drug propiverine (Taiho Pharmaceutical, Tokyo, Japan) on urethral function. MATERIALS AND METHODS: Urethral pressure and rhythmic bladder pressure were simultaneously monitored in urethane anesthetized female Sprague-Dawley rats. Prostaglandin E(2) was continuously administered intravesically or intraurethrally to induce detrusor overactivity. To eliminate the influence of bladder activity and monitor urethral baseline pressure isovolumetric pressure of the urethra was then recorded after cystectomy and ligation of the external urethral meatus. Furthermore, in vitro contractile responses of the urethral circular smooth muscle to field stimulation were examined in the presence of propiverine, tamsulosin (Taiho Pharmaceutical), verapamil, omega-conotoxin and atropine (Sigma). RESULTS: Intravesical or intraurethral administration of prostaglandin E(2) significantly decreased the bladder contraction interval by 10.7% and 36.0%, respectively. Intra-arterial administration of 2 x 10(2) nM/kg propiverine significantly increased the bladder contraction interval in rats receiving intraurethral prostaglandin E(2) by 81.8% but it had no marked effect on rats receiving intravesical prostaglandin E(2). Significant decreases in urethral baseline pressure were found after propiverine administration. Field stimulation induced contraction was inhibited by propiverine and verapamil but not by tamsulosin, omega-conotoxin or atropine. CONCLUSIONS: These results suggest that the inhibitory effects of propiverine are more prominent in rats with detrusor overactivity induced by intraurethral prostaglandin E(2) than by intravesical prostaglandin E(2). Propiverine may compensate for detrusor function by decreasing urethral resistance in the voiding phase.  相似文献   
945.
Effects of aromatase inhibitors (AIs) on the human skeletal system due to systemic estrogen depletion are becoming clinically important due to their increasing use as an adjuvant therapy in postmenopausal women with breast cancer. However, possible effects of AIs on human bone cells have remained largely unknown. We therefore studied effects of AIs including the steroidal AI, exemestane (EXE), and non-steroidal AIs, Aromatase Inhibitor I (AI-I) and aminoglutethimide (AGM), on a human osteoblast. We employed a human osteoblast cell line, hFOB, which maintains relatively physiological status of estrogen and androgen pathways of human osteoblasts, i.e., expression of aromatase, androgen receptor (AR), and estrogen receptor (ER) beta. We also employed osteoblast-like cell lines, Saos-2 and MG-63 which expressed aromatase, AR, and ERalpha/beta in order to further evaluate the mechanisms of effects of AIs on osteoblasts. There was a significant increment in the number of the cells following 72 h treatment with EXE in hFOB and Saos-2 but not in MG-63, in which the level of AR mRNA was lower than that in hFOB and Saos-2. Alkaline phosphatase activity was also increased by EXE treatment in hFOB and Saos-2. Pretreatment with the AR blocker, flutamide, partially inhibited the effect of EXE. AI-I exerted no effects on osteoblast cell proliferation and AGM diminished the number of the cells. hFOB converted androstenedione into E2 and testosterone (TST). Both EXE and AI-I decreased E2 level and increased TST level. In a microarray analysis, gene profile patterns following treatment with EXE demonstrated similar patterns as with DHT but not with E2 treatment. The genes induced by EXE treatment were related to cell proliferation, differentiation which includes genes encoding cytoskeleton proteins. We also examined the expression levels of these genes using quantitative RT-PCR in hFOB and Saos-2 treated with EXE and DHT and with/without flutamide. HOXD11 gene known as bone morphogenesis factor and osteoblast growth-related genes were induced by EXE treatment as well as DHT treatment in both hFOB and Saos-2. These results indicated that the steroidal aromatase inhibitor, EXE, stimulated hFOB cell proliferation via both AR dependent and independent pathways.  相似文献   
946.
Brain function in IBS patients   总被引:1,自引:0,他引:1  
Irritable bowel syndrome(IBS) is functional disorder that is characterized by abdominal pain and changes in stool habits, and possibly related to abnormal brain-gut communication. Recent studies using brain imaging suggest the brain functions of IBS patients may be possibly different from that of control. We, in this article, review the recent knowledge regarding this point.  相似文献   
947.
IntroductionSalvage treatment for acquired resistance to epidermal growth factor receptor tyrosine kinase inhibitor in patients with non–small-cell lung cancer is a matter of clinical concern. Several retrospective reports have indicated the usefulness of epidermal growth factor receptor tyrosine kinase inhibitor readministration; however, there have been few prospective studies.Materials and MethodsThis study was designed to prospectively evaluate the clinical efficacy of gefitinib readministration in patients with advanced or metastatic non–small-cell lung cancer who responded well to initial gefitinib treatment. The subjects received at least 1 regimen of cytotoxic chemotherapy after progressive disease with the initial gefitinib therapy. Gefitinib administration (250 mg/d, orally) was started after progressive disease with the previous chemotherapeutic regimen. The primary endpoint in the present study was the response rate.ResultsTwenty patients were enrolled between April 2007 and May 2011. Three patients achieved partial response, and 6 showed stable disease. Thus, the overall response rate and disease control rate of gefitinib readministration were 15% (95% CI, 3.21-37.9) and 45% (95% CI, 23.1-68.5), respectively. Median progression-free survival and overall survival from the start of gefitinib readministration were 2.0 months (95% CI, 0.9-3.1 months) and 12.0 months (95% CI, 8.0-16.0 months), respectively.ConclusionThese results suggest that gefitinib readministration may be an option, albeit with a low response rate and short progression-free survival, for patients who responded well to initial gefitinib followed by systemic chemotherapy. These findings provide valuable information for the management of previous gefitinib responders.  相似文献   
948.
949.
The aim of this study was to verify the utility of second-look sonography using real-time virtual sonography (RVS)-a coordinated sonography with an MRI system that uses an image fusion technique with magnetic navigation-on the sonographic evaluation of MRI-detected lesions of the breast. Of the 196 consecutive patients who were examined with breast MRI in our hospital from 2006 to 2009, those patients who underwent second-look sonography to identify MRI-detected lesions were enrolled in this study. MRI was performed using a 1.5-T imager with the patient in a supine position. To assess the efficacy benefits of RVS, the correlations between lesion detection rates, MRI features, distribution, and histopathological classification on second-look sonography using conventional B-mode or RVS were analyzed. Of the 196 patients, 55 (28?%) demonstrated 67 lesions initially detected by MRI, followed by second-look sonography. Of the 67 MRI-detected lesions, 18 (30?%) were identified with second-look sonography using conventional B-mode alone, whereas 60 (90?%) lesions were detected with second-look sonography using RVS (p?相似文献   
950.
We report a 60-year-old man with chronic inflammatory demyelinating polyneuropathy (CIDP) accompanying systemic lupus erythematosus (SLE) and Sj?gren syndrome (SS). He was admitted to our hospital because of progressive weakness and dysesthesia in the distal parts of the bilateral upper and lower extremities. We diagnosed the illness as CIDP and treated him with steroids, plasma filtration and high-dose intravenous immunoglobulin therapy (IvIg). Consequently, his symptoms improved gradually and he was discharged. However, 2 years after the first admission, he experienced dyspnea on effort and chest X-ray demonstrated right pleural effusion. Consequently, he gradually developed gait disturbance, loss of taste, and severe dysesthesia in his lower limbs. Therefore, he was admitted again. On neurological examination, mild weakness was detected in all limbs distally. Deep tendon reflexes were absent. The sensation of position and vibration was diminished in the fingers and toes. He could not walk by himself and demonstrated an ataxic gait with a wide base. Examination of cranial nerves demonstrated no abnormalities, except for loss of taste. Serological examination demonstrated positive auto-antibodies including antinuclear, anti-DNA, and anti-SS-A antibodies. Urinalyses showed albuminuria and microscopic hematuria. Cerebrospinal fluid (CSF) was clear and colorless, containing 3 mononuclear cells per cubic mm, with a protein of 275 mg/dl. Magnetic resonance images (MRIs) of the brain and entire spine were normal. Neurophysiological studies demonstrated an absence of sensory nerve action potentials in the right arm and markedly slow conduction velocities, conduction block in the ulnar forearm segment and absence of F waves in all limbs. The renal biopsy revealed lupus nephritis. The lip biopsy demonstrated chronic sialoadenitis consistent with SS, altough patient did not show symptoms of arthritis or vasculitis. It is well known that mononeuritis multiplex and acute demyelinating polyneuropathy accompany SLE. However there are few reports that describe the occurrence of CIDP in patients with SLE, and the association of "CIDP-like" neuropathy in patients with SS. Our case suggests that the autoimmune disease associated with SLE and SS may induce "CIDP-like" inflammatory demyelinating polyneuropathy.  相似文献   
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