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61.
We report four cases of isolated GCD of the stomach and proximal small intestine that were refractory to conventional management. Gastric ulcers were present in patients 1-3 for 4, 13, and 22 years and erosive gastritis in patient 4 was present for at least 2 years. High-dose proton pump inhibition and H. pylori eradication failed to induce healing. Neither ileocolonic lesions nor typical CD pathology with granulomas were detected in any of the patients, but all behaved clinically like CD. The three patients with gastric ulcers failed initial partial gastrectomy and required multiple reoperations because of duodenojejunal ulceration and anastomotic stricture formation. Patient 1 did not improve with infliximab. Patient 2 healed on steroids and infliximab. Patient 3 did not tolerate sulfasalazine and steroids and is currently being treated with 6-mercaptopurine (6-MP). Patient 4 healed on prednisone and 6-MP. We conclude that GCD should be considered in isolated refractory gastroduodenal inflammation and ulceration. Immunomodulators and surgery may play a role in the treatment of this difficult-to-manage condition.  相似文献   
62.
This review explores the health and social burden of some of the main respiratory diseases (asthma, chronic obstructive pulmonary disease, cryptogenic fibrosing alveolitis, cystic fibrosis, lung cancer, mesothelioma, obstructive sleep apnoea and tuberculosis) in order to increase awareness of these diseases and highlight areas where improvements in care are required. The overall impact of respiratory diseases in the U.K. in terms of prevalence, mortality, morbidity and economic costs, with particular reference to secondary care has been considered and comparisons made with the rest of Europe where data are available. Respiratory diseases are responsible for a significant proportion of serious morbidity and premature death among the population of the U.K. and they will continue to present a growing challenge; special support is needed to tackle this burden.  相似文献   
63.
64.
By means of immunohistochemical staining, cells actively infected with human herpesvirus 6 (HHV-6) were found in central nervous system tissues from 8 (73%) of 11 patients with definite multiple sclerosis (MS). Interestingly, 17 (90%) of 19 tissue sections showing active demyelination were positive for HHV-6-infected cells compared with only 3 (13%) of 23 tissue sections free of active disease (P<.0001). Central nervous system tissues from 2 of 28 normal persons and patients with other inflammatory demyelinative diseases were positive for HHV-6-infected cells (P<.0001), and the 2 positive cases were diagnosed as having HHV-6 leukoencephalitis. By use of a rapid culture assay, blood samples from 22 (54%) of 41 patients with definite MS were found to contain active HHV-6 infections, compared with 0 of 61 normal controls (P<.0001). No significant difference was found between HHV-6 viremia-positive and HHV-6 viremia-negative MS patients with respect to type of disease (relapsing/remitting or progressive). In contrast, patients with active HHV-6 viremia were significantly younger and had shorter durations of disease than did HHV-6 viremia-negative patients.  相似文献   
65.
66.
Abstract

During an ordinary work day blood pressure was self-monitored once every hour in two samples of asymptomatic nonmedicating 28-year-old men. They were selected on the basis of previous compulsory blood pressure recordings made at the age of 18 when they had been drafted for military service. Subjects in the ?original hypertensive sample” with ?strain” occupations (hectic and uncontrollable, such as waiter, driver and cook) had more marked elevations of systolic blood pressure during work hours than other subjects.  相似文献   
67.
The regulation of the tyrosine phosphorylation of key signaling molecules by tyrosine kinases and phosphatases is essential for BCR-triggered signaling cascades during B cell selection process. We used the non-selective tyrosine phosphatase inhibitor vanadate to study the importance of the late regulation of the tyrosine phosphorylation for BCR-triggered G1 growth arrest and apoptosis in Ramos-BL B cells. Vanadate induces G2M growth arrest in a dose-dependent manner and prevents BCR-triggered apoptosis. Vanadate-induced upregulation of the tyrosine phosphorylation is concomitant with increased expression of cyclin B and inhibition of caspase-3 activation and PARP cleavage. The anti-apoptotic effect of vanadate was observed even when added up to 6 hours after the treatment of Ramos-BL B cells with anti-IgM. Vanadate increases BCR-triggered tyrosine phosphorylation of the cytosolic tyrosine phosphatases, SHP-1 and SHP-2 after 24 hours. Co-stimulation with anti-CD40 prevents anti-IgM-triggered tyrosine phosphorylation of these phosphatases and up-regulates the expression of SHP-1. We conclude that the regulation of the tyrosine phosphatase activity is indispensable for BCR-triggered execution of the apoptosis in Ramos-BL B cells.  相似文献   
68.
Background The study was performed with an aim to map the pattern of metastasis of squamous cell carcinomas of buccal mucosa to various cervical lymph node levels and analyze its correlation with primary tumor size and histo-pathological grading. Material and Methods 254 patients with squamous cell carcinoma of the buccal mucosa treated with surgery first approach were analyzed retrospectively. The tumor size was noted from pre-operative CT Scans and were divided into early and advanced tumors. The resected specimen was studied to note the histo-pathological grading of the squamous cell carcinoma and the metastatic deposits at various lymph node levels. Results Out of 254 patients (149 females, 105 males), 145 patients showed histo-pathologically proven metastatic deposits in one or more lymph nodes out of which there were 56 patients showing occult metastasis. 78/145 patients showed metastatic involvement of level IB and/or IA lymph nodes, 31 showed involvement of level II and/or I lymph nodes, 27 showed involvement of level III with or without involvement of level I and II and 9 showed metastasis to level IV and V lymph nodes with or without level I, II or III lymph nodes. Cervical lymph node metastasis had statistically significant association with tumor size with advanced tumors showing worse pattern of metastatic spread beyond level I and II lymph nodes. As the degree of differentiation of squamous cell carcinoma reduced, they were more prone for cervical metastasis with moderately and poorly differentiated squamous cell carcinoma showing higher involvement of level III, IV and V lymph nodes. Conclusions The majority of buccal mucosa cases showed metastasis to level I, II and III lymph nodes out of which level IB and/or IA was most frequently involved. Metastasis to level IV and V lymph nodes was rare and was seen especially in patients with advanced primary tumor and poor histo-pathologic differentiation. Key words:Oral squamous cell carcinoma (OSCC), cervical lymph node metastasis, histologic differentiation, locally advanced disease.  相似文献   
69.
Eosinophils stimulate fibroblast DNA synthesis   总被引:9,自引:0,他引:9  
Pincus  SH; Ramesh  KS; Wyler  DJ 《Blood》1987,70(2):572-574
Fibrosis complicates a number of chronic inflammatory diseases and occurs in some conditions following chronic hypereosinophilic syndromes. We assessed whether eosinophils might be a source of fibrogenic factors. Extracts of human and guinea pig cell populations enriched for eosinophils contained substances that stimulated tritiated thymidine incorporation by human fibroblasts. Supernatants derived from resting eosinophils and extracts prepared from eosinophil granules also contained fibrogenic factors. Our findings demonstrate a new potential role for eosinophils and suggest a causal relationship between tissue eosinophilia and scar formation in certain parasitic conditions.  相似文献   
70.
Akagawa  KS; Takasuka  N; Nozaki  Y; Komuro  I; Azuma  M; Ueda  M; Naito  M; Takahashi  K 《Blood》1996,88(10):4029-4039
We previously showed that granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage colony-stimulating factor (M-CSF) stimulate the differentiation of human monocytes into two phenotypically distinct types of macrophages. However, in vivo, not only CSF but also many other cytokines are produced under various conditions. Those cytokines may modulate the differentiation of monocytes by CSFs. In the present study, we showed that CD14+ adherent human monocytes can differentiate into CD1+relB+ dendritic cells (DC) by the combination of GM-CSF plus interleukin-4 (IL-4) and that they differentiate into tartrate-resistant acid phosphatase (TRAP)-positive osteoclast-like multinucleated giant cells (MGC) by the combination of M-CSF plus IL-4. However, the monocyte-derived DC were not terminally differentiated cells; they could still convert to macrophages in response to M-CSF. Tumor necrosis factor-alpha (TNF-alpha) stimulated the terminal differentiation of the DC by downregulating the expression of the M-CSF receptor, cfms mRNA, and aborting the potential to convert to macrophages. In contrast to IL-4, interferon-gamma (IFN-gamma) had no demonstrable effect on the differentiation of monocytes. Rather, IFN- gamma antagonized the effect of IL-4 and suppressed the DC and MGC formation induced by GM-CSF + IL-4 and M-CSF + IL-4, respectively. Taken together, these results provide a new aspect to our knowledge of monocyte differentiation and provide evidence that human monocytes are flexible in their differentiation potential and are precursors not only of macrophages but also of CD1+relB+DC and TRAP-positive MGC. Such a diverse pathway of monocyte differentiation may constitute one of the basic mechanisms of immune regulation.  相似文献   
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