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1.
Background: Gastrointestinal stromal tumors (GIST) are one of the most common mesenchymal tumors of the gastrointestinal tract. GIST are defined by positive immunohistochemical staining for KIT or CD34 and thus are generally diagnosed after surgery. Because small GIST are rarely diagnosed before surgery, the clinical course of these small tumors is not clear. The aim of the present study was to follow changes in size and configuration of small GIST that were pathologically confirmed using endoscopic ultrasonography‐guided fine‐needle aspiration biopsy (EUS‐FNAB). Methods: Between July 1997 and December 2003, 16 tumors in 16 patients (10 men and 6 women) with an immunohistochemical diagnosis of GIST were regularly followed in our hospital. The median patient age when EUS‐FNAB was performed was 62 years (range 26–82 years) and the median follow‐up period was 4.9 years (range 0.5–9.6 years). Results: Fourteen tumors showed no remarkable changes in size and shape during follow up compared with the initial diagnosis. Two tumors enlarged: one tumor approximately doubled its diameter in 8 years and the other tumor increased from 1.8 cm at diagnosis to up to 10 cm after only 2 years. Doubling time of the latter tumor was calculated as 3.1 months. Conclusions: We conclude that EUS‐FNAB might be a good modality for final diagnosis of GIST without surgery, and that GIST without rapid growth on follow up can be endoscopically followed.  相似文献   
2.
We conducted a clinical study on respiratory infections complicating bronchial asthma. Transtracheal aspiration (TTA) was performed 37 times in 22 patients. The most frequently isolated organism was H. influenzae. The patients in whom organisms were isolated on TTA had a high incidence of fever and evidence of inflammation. Antimicrobial therapy caused a decrease in indices of inflammation (white blood cell count and ESR), but was less effective against the asthmatic symptoms. Respiratory infection may play a complex role in the clinical picture of bronchial asthma.  相似文献   
3.
Cholinergic influences on use-dependent plasticity.   总被引:7,自引:0,他引:7  
Motor practice elicits use-dependent plasticity in humans as well as in animals. Given the influence of cholinergic neurotransmission on learning and memory processes, we evaluated the effects of scopolamine (a muscarinic receptor antagonist) on use-dependent plasticity and corticomotor excitability in a double-blind placebo-controlled randomized design study. Use-dependent plasticity was substantially attenuated by scopolamine in the absence of global changes in corticomotor excitability. These results identify a facilitatory role for cholinergic influences in use-dependent plasticity in the human motor system.  相似文献   
4.
The experimental system utilized in investigating the correlation between the chemical structures of muramyl peptides and their protective activities in the sepsis type of systemic infections caused by Escherichia coli was applied in evaluating the enhancement of resistance to infection induced by 32 synthetic glycopeptide analogs, including 6-O-acyl derivatives and 1-alpha-O-benzyl derivatives of muramyl dipeptide (N-acetyl muramyl-L-alanyl-D-isoglutamine). In assessing the 6-O-acyl derivatives of muramyl dipeptide, we found that the degree of protective activity was attributable to the kinds of fatty acids introduced. Acylation of the 6-hydroxy group on the muramic acid moiety in muramyl dipeptide with natural mycolic acid or a synthetic fatty acid possessing either an alpha-branched or an alpha-branched, beta-hydroxylated group resulted in a decrease in or a disappearance of the protective activity of muramyl dipeptide. Acylation with a normal fatty acid or an iso fatty acid resulted in a retention or enhancement of muramyl dipeptide activity. The activity of acylated derivatives containing linear fatty acids was stimulated by increasing the chain length up to 18 carbon atoms. The highest degree of protective activity occurred with the derivatives acylated with straight-chain fatty acids, particularly with the derivatives acylated with palmitic acid and arachidic acid. Benzylation of the 1-hydroxy group of muramyl dipeptide resulted in a decrease in or a loss of protective activity.  相似文献   
5.
Adult Still's disease reflects a Th2 rather than a Th1 cytokine profile   总被引:2,自引:0,他引:2  
Adult Still's disease (ASD) is a chronic multisystemic disease. Extraordinarily high serum levels of IL-18 in ASD patients have been described, whereas the mechanism remains to be clarified. This study aimed to evaluate proinflammatory cytokines and to consider their pathological roles. In patients with rheumatic diseases (n = 151), blood samples were taken at the active phase and the serum levels of IL-18 and other proinflammatory cytokines were measured by ELISA. The extra-high levels of IL-18 were confirmed selectively in ASD patients (n = 10). In the active phase of ASD patients, the levels of IL-6 were elevated accordingly, but IL-1beta and TNF-alpha were undetectable. As to Th1-Th2 cytokines, the levels of IL-4 and IL-13, but not INF-gamma, IL-12, or IL-2, were elevated in all ASD patients examined. Moreover, the serum levels of IL-18 showed a good correlation with those of IL-4, suggesting that ASD reflects a Th2 rather than a Th1 cytokine profile.  相似文献   
6.
A 69-year-old woman was admitted to our hospital because of dysphasia. The upper G-I examination showed a stenosis at the middle thoracic esophagus and poorly differentiated adenocarcinoma was revealed histologically. Chest CT scan showed a mass shadow in the right upper lobe of the lung. She had undergone a partial resection of right upper lobe because of lung cancer seven years before. She was diagnosed as metachrous double carcinoma of the lung and the esophagus. The method of surgery included right upper lobectomy of the lung, esophagectomy and intrathoracic esophageal reconstruction using the gastric tube. The patient manifested pneumonia due to the failure of the sutures after the surgery and died on the twentieth postoperative day. When conducting simultaneous resection of both cancer and esophageal reconstruction for the double cancer of the lung and the esophagus, it was considered necessary to conduct the anastomosis outside the thoracic cavity for the purpose of preventing the pulmonary complication due to the failure of the sutures.  相似文献   
7.
Aims: This pilot randomized comparative study investigated changes in motor performance and indices of neuroplasticity associated with occupation-based intervention and repetitive task practice in the recovery of occupational performance following stroke. Method: Sixteen participants received either occupation-based intervention or repetitive task practice for eight 55-minute sessions. Motor performance was measured by the Fugl Meyer Assessment (FMA), Stroke Impact Scale (SIS), the Canadian Occupational Performance Measure (COPM) and the Goal Attainment Scale (GAS). Indices of neuroplastic change were assessed by transcranial magnetic stimulation (TMS). Results: Both occupation-based intervention and repetitive task practice groups demonstrated significant changes on the FMA and the occupation-based group demonstrated significant changes on the GAS goals. Neurophysiological measures showed enlargement in TMS volume maps in the affected hemisphere for both groups. Conclusion: Occupation-based and repetitive task practice interventions can yield similar improvements in chronic stroke.  相似文献   
8.
Using mainly changes in the amount of sputum as an index of the infectious course of chronic lower respiratory tract infection associated with purulent sputum over years, the disease was divided into stable and acute exacerbated phases and a bacteriological investigation using transtracheal aspiration (TTA) conducted. TTA was performed 107 and 45 episodes during stable phases and acute exacerbated phases respectively. Monomicrobial and polymicrobial infection were detected most frequently during the stable and acute exacerbated phases respectively (p less than 0.01). During the stable phases, the single organisms detected most frequently were H. influenzae (26 episodes) and P. aeruginosa (20 episodes), while in the cases in which multiple organisms were detected during stable phases, combination including H. influenzae were most common (19 episodes). H. influenzae was the most frequently detected organism in cases showing single organisms during acute exacerbated phases (7 episodes). In the cases in which multiple organisms were detected as well, H. influenzae was the most commonly detected organism assumed to predispose to exacerbation (7 episodes), while P. aeruginosa was not found. These results suggest that in chronic lower respiratory tract infection. H. influenzae and P. aeruginosa are important as persistent infective organisms, while H. influenzae are important in acute exacerbation.  相似文献   
9.
Clinical studies were made over 7 years on 9 cases to whom long-term chemotherapy with EM was administered for chronic airway infection. 1) Clinical effectiveness: Highly effective in 8 cases; Improvement in QOL was observed in 8 cases. Bacteriological effect: In 7 cases, pathogenic bacteria disappeared. 2) No side effects were observed. 3) Changes in PaO2 levels with the passage of time: In most cases, PaO2 reached a plateau within 1 year. Although in some cases, there was subsequent elevation. 4) The frequency of catching cold over the 7 years period was low with an average of 1.2 times/year per subject. In only 2 cases were subject hospitalized due to acute exacerbation triggered by a cold. 5) Mucociliary transport improved in 7 out of 8 cases examined. However, only 4 of these recovered normal transport. The effect of EM in the other cases in which clinical improvement was not demonstrated was deemed slightly effective. On the basis of the above findings, it was suggested that long-term chemotherapy using EM was clinically efficacious. This is based on the fact that its efficacy, including amelioration of QOL appeared within one year of the initiation of therapy, and continued without decline for over 7 years.  相似文献   
10.
The aim of this study was to clarify the nature of the clonal lymphocyte infiltration in Sjögren''s syndrome (SS) patients associated with lymphoproliferative disorders. We examined B cell clonality in lymphoproliferative tissues from six primary SS patients associated with lymphoproliferative disorders or lymphoma by cloning and sequencing of the gene rearrangement of the immunoglobulin heavy chain complementarity determining region 3 (IgVH–CDR3). Three patients with sequential observation showed progressional clonal expansion with the presence of the same subclone in different tissues during the course of disease. Among them, one patient developed mucosa-associated lymphoid tissue (MALT) lymphoma in glandular parotid. The other three SS patients concomitant with malignant B cells lymphomas showed different clonal expansion of B cells between nodal sites and salivary glands. The cloanality analysis indicated that monoclonal B cell population could spread from one glandular site to another site during the course of SS, suggesting that the malignant clone may arise from the general abnormal microenvironment, not restricted to the glandular tissue, in some SS patients.  相似文献   
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