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61.
淋巴增强因子-1是Wnt信号路径的重要组成成分,在由上皮和间充质的相互作用而产生的器官如牙的发育中发挥着重要的调节作用。下面就其在调控牙发育、维持牙上皮细胞活性、抑制成骨细胞的终极分化和在口腔恶性肿瘤的发生发展中的作用作一综述。  相似文献   
62.
To investigate the feasibility of arterial spin labeling (ASL) blood flow (BF) and its histogram analysis to distinguish early-stage nasopharyngeal carcinoma (NPC) from nasopharyngeal lymphoid hyperplasia (NPLH).Sixty-three stage T1 NPC patients and benign NPLH patients underwent ASL on a 3.0-T magnetic resonance imaging system. BF histogram parameters were derived automatically, including the mean, median, maximum, minimum, kurtosis, skewness, and variance. Absolute values were obtained for skewness and kurtosis (absolute value of skewness [AVS] and absolute value of kurtosis [AVK], respectively). The Mann–Whitney U test, receiver operating characteristic curve, and multiple logistic regression models were used for statistical analysis.The mean, maximum, and variance of ASL BF values were significantly higher in early-stage NPC than in NPLH (all P < 0.0001), while the median and AVK values of early-stage NPC were also significantly higher than those of NPLH (all P < 0.001). No significant difference was found between the minimum and AVS values in early-stage NPC compared with NPLH (P = 0.125 and P = 0.084, respectively). The area under the curve (AUC) of the maximum was significantly higher than those of the mean and median (P < 0.05). The AUC of variance was significantly higher than those of the other parameters (all P < 0.05). Multivariate analysis showed that variance was the only independent predictor of outcome (P < 0.05).ASL BF and its histogram analysis could distinguish early-stage NPC from NPLH, and the variance value was a unique independent predictor.  相似文献   
63.
Eosinophilic otitis media (EOM), which is characterized by the accumulation of eosinophils in middle ear effusion and the middle ear mucosa, is a refractory type of otitis media that is often associated with asthma. Although an early diagnosis and appropriate treatment are necessary to prevent the progression of hearing loss in patients with EOM, there are currently no well-established treatments for this condition. We treated a 60-year-old male patient with asthma and EOM. The patient’s asthma was poorly controlled, despite the use of high-dose inhaled corticosteroids, long-acting beta-agonist treatment, and the regular use of systemic corticosteroids. Mepolizumab, an anti-IL-5 monoclonal antibody, was started to treat the patient’s refractory asthma. At 4 months after the initiation of mepolizumab treatment, the patient’s asthma, hearing, and middle ear effusion improved. The present case suggests that mepolizumab therapy can control EOM and asthma.  相似文献   
64.
65.
BACKGROUND & AIMS: The aim of our study was to conduct a systematic review of studies evaluating prevalence of hepatitis C virus (HCV) infection in B-cell non-Hodgkin's lymphoma (B-NHL) and to perform a meta-analysis of case-control studies comparing this prevalence with that of a reference group. METHODS: Data sources: Electronic databases and the Cochrane Controlled Trials Register. Study selection: Studies evaluating prevalence of HCV infection in patients with B-NHL. Studies comparing HCV prevalence in B-NHL (cases) and in a reference group (controls) were included in the meta-analysis. Data extraction: Author/country, diagnostic method (serology/PCR), control type, matching/design, and VHC prevalence. Data synthesis: Prevalence of HCV infection and meta-analysis combining the odds ratios (OR). RESULTS: Forty-eight studies (5542 patients) were identified. Mean HCV infection prevalence was 13% (95% CI: 12%-14%), which was higher in Italy (20%) and Japan (14%). Ten studies compared HCV prevalence in B-NHL (17%) and healthy controls (1.5%) (OR: 10.8; 95% CI: 7.4-16), results being homogeneous; OR increased up to 14.1 when only Italian studies were considered. Sixteen studies compared HCV prevalence in B-NHL (13%) and in other hematologic malignancies (2.9%) (OR: 4.2; 95% CI: 2.5-7), also with homogeneous results; OR increased up to 7.8 when subanalysis included only Italian studies. CONCLUSIONS: HCV prevalence in patients with B-NHL is approximately 15%, higher than that reported not only in general population (1.5%) but also in patients with other hematologic malignancies (2.9%), suggesting a role of HCV in the etiology of B-NHL. The striking geographic variation in this association suggests that genetic and/or environmental factors are also involved in the pathogenesis of this disorder.  相似文献   
66.
Purpose. Hepatic bile duct injuries are characteristic histological findings in patients with chronic hepatitis C virus (HCV) infection. However, the pathogenesis and clinical significance of this phenomenon remain unclear. The aims of this study were to evaluate the prevalence and clinical significance of hepatic bile duct injuries in Chinese patients with chronic hepatitis C. Methods. One hundred and seventeen Chinese patients with chronic hepatitis C were enrolled. Clinical, biochemical, immunological (serum autoantibodies and cryoglobulinemia), histological, and virological data (serum HCV RNA titer and HCV genotype) were compared between patients with and without hepatic bile duct injuries. Results. Eighty-three (71%) of the 117 patients with chronic hepatitis C had hepatic bile duct injuries. Patients with hepatic bile duct injuries had a significantly higher frequency of HCV genotype 1b; a higher mean serum globulin level; significantly higher mean scores for histological periportal necro-inflammation, portal inflammation, and fibrosis; and more severe portal lymphoid aggregation/follicles when compared with patients without hepatic bile duct injuries (P < 0.05, all). No significant differences in the presence of serum autoantibodies, cryoglobulinemia, mean serum HCV RNA titer, or response to interferon treatment were noted between the two groups. Multivariate logistic regression analysis showed that HCV genotype 1b infection, portal inflammation, and lymphoid aggregation/follicles were significant independent predictors associated with hepatic bile duct injuries. Conclusions. The presence of hepatic bile duct injuries in Chinese patients with chronic hepatitis C was significantly correlated with HCV genotype 1b infection, and the patients with these injuries had more severe portal inflammation and formation of lymphoid aggregates/follicles. Received: September 8, 2000 / Accepted: January 26, 2001  相似文献   
67.
To explore the basic mechanical properties and size effects of recycled aggregate concrete (RAC) with different substitution ratios of coarse recycled concrete aggregates (CRCAs) to replace natural coarse aggregates (NCA), the failure modes and mechanical parameters of RAC under different loading conditions including compression, splitting tensile resistance and direct shear were compared and analyzed. The conclusions drawn are as follows: the failure mechanisms of concrete with different substitution ratios of CRCAs are similar; with the increase in substitution ratio, the peak compressive stress and peak tensile stress of RAC decrease gradually, the splitting limit displacement decreases, and the splitting tensile modulus slightly increases; with the increase in the concrete cube’s side length, the peak compressive stress of RAC declines gradually, but the integrity after compression is gradually improved; and the increase in the substitution ratio of the recycled aggregate reduces the impact of the size effect on the peak compressive stress of RAC. Furthermore, an influence equation of the coupling effect of the substitution ratio and size effect on the peak compressive stress of RAC was quantitatively established. The research results are of great significance for the engineering application of RAC and the strength selection of RAC structure design.  相似文献   
68.
BACKGROUND: The purpose of the present paper was to investigate the clinical, endoscopic and histological features of 31 patients with gastric mucosa-associated lymphoid tissue (MALT) lymphoma to enable correct, early stage diagnosis. METHODS: A retrospective study was undertaken of 31 patients with gastric MALT lymphoma. The cases were examined immunohistologically with anti-CD(20CY) and CD(45RO) antibodies for further diagnosis. Helicobacter pylori infection was also detected with modified Giemsa staining. RESULTS: Patients with MALT lymphoma were aged between 22 and 73 years (mean, 45.0 years), and the male:female ratio was 11:20. The patients presented with non-specific symptoms, but chronic epigastric pain was the common symptom in a large proportion of the cases. The gastric smaller curvature was involved in 83.9% of cases (26/31) and in 13/31 cases (41.9%) it was confined the antrum. Under endoscopy, large and deep ulcers were similar to cancers in the majority of patients. Only 29.0% of patients were diagnosed by endoscopy on first examination. CD(20CY) were expressed in all cases and CD(45RO) expressed in only one case among 10 cases of indefinite diagnosis. Helicobacter pylori infection was found in 87.1% of patients. CONCLUSIONS: These findings suggest that primary gastric MALT lymphoma has unique clinical, endoscopic and histological features. The diagnosis for primary gastric MALT lymphoma was delayed not only due to the non-specific symptoms but also due to lack of attention to its features. Endoscopy and submucosal multiple biopsy were the principal diagnostic tools in patients with gastric MALT lymphoma. CD(20CY) and CD(45RO) immunological staining are recommended, especially for patients with indefinite diagnosis of gastric MALT lymphoma.  相似文献   
69.
The content of acid and alkaline phosphatases was studied in the lymphocytes of the peripheral blood, bone marrow, and lymphoid organs (thymus, spleen, lymph node) of intact noninbred rats. The mean percentage of cells containing the enzymes was determined. Their organ and species characteristics are described.Central Research Laboratory and Department of Pathophysiology, Tomsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR I. V. Toroptsev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 2, pp. 158–159, February, 1978.  相似文献   
70.
Natural killer (NK) cells and lymphoid tissue inducer (LTi) cells were discovered more than 40 and 20 years ago, respectively. These two cell types were initially studied for their unique functions in the elimination of infected or transformed cells, and in the development of lymphoid tissues. It took an additional 10 years to realize that NK cells and LTi cells were members of a larger family of innate lymphoid cells (ILCs), whose phenotypes and functions mirror those of T cells. Many mouse models have since been developed to identify and isolate ILCs, map their developmental pathways and characterize their functions. Because of the similarity between ILCs and T cells, this exploration remains a challenge. In spite of this, a broad range of mouse models available to researchers has lead to significant progress in untangling the unique roles of ILCs early in defense, regulation of adaptive immunity and homeostasis. Here, we review these mouse models, and discuss their strengths and limitations.  相似文献   
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