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991.
Rationale:Gastric adenocarcinoma of fundic gland (chief cell predominant type) (GA-FG-CCP) is a new, rare variant of gastric adenocarcinoma, which is characterized by mild nuclear atypia and specific immunohistochemical markers.Patient concerns:An 84-year-old Chinese man was referred to our hospital for endoscopic resection of a gastric lesion.Interventions:We performed endoscopic submucosal dissection, and successfully removed the lesion.Diagnosis:Esophago gastroduodenoscopy showed a slightly elevated lesion with a diameter of 22 mm in the posterior wall of cardia. Magnifying endoscopy with narrow band imaging revealed an abnormal microsurface and microvessels on the tumor surface. Endoscopic ultrasonography revealed a hypoechoic mass located in the first layer. The pathological diagnosis of the biopsy specimens indicated that the tumor was high grade intraepithelial neoplasia. The pathological diagnosis differed between the superficial and deeper part of the lesion. The superficial part was composed of a tubular structure with prominent atypia and was diagnosed as well differentiated intestinal adenocarcinoma. The deeper part was composed of a well-differentiated tubular adenocarcinoma mimicking the fundic gland cells, mainly the chief cells. The tumor cells showed mild nuclear atypia and was positive for pepsinogen-I (PG-I) and mucin-6 (MUC6). This deeper part was diagnosed as GA-FG-CCP.Outcomes:The tumor was successfully removed. This patient had no discomfort during the follow-up period (10 months).Lessons:We present a rare case of GA-FG-CCP coexisted with well-differentiated tubular adenocarcinoma. GA-FG-CCP exists in the deep mucosal layer and the muscularis mucosa, which could not be found under endoscopy, but could be discerned in pathology with mild nuclear atypia and special biomarkers. 相似文献
992.
Ma Hao Zhou Tao Li Xiang Maraganore Demetrius Heianza Yoriko Qi Lu 《Age (Dordrecht, Netherlands)》2022,44(3):1479-1488
GeroScience - We examined the interactions between educational attainment and genetic susceptibility on dementia risk among adults over 60 years old. A total of 174,161 participants were... 相似文献
993.
Hanzel Jurij Almradi Ahmed Istl Alexandra C. Yang Mei Lucy Fleshner Katherine A. Parker Claire E. Guizzetti Leonardo Ma Christopher Singh Siddharth Jairath Vipul 《Digestive diseases and sciences》2022,67(2):646-660
Digestive Diseases and Sciences - Postoperative complication rates in patients with inflammatory bowel disease (IBD) receiving preoperative biologics have been analyzed without considering the... 相似文献
994.
995.
Min Dong Xiangyu Lu Yide Ma Yanan Guo Yurun Ma Keju Wang 《Journal of digital imaging》2015,28(5):613-625
Breast cancer is becoming a leading death of women all over the world; clinical experiments demonstrate that early detection and accurate diagnosis can increase the potential of treatment. In order to improve the breast cancer diagnosis precision, this paper presents a novel automated segmentation and classification method for mammograms. We conduct the experiment on both DDSM database and MIAS database, firstly extract the region of interests (ROIs) with chain codes and using the rough set (RS) method to enhance the ROIs, secondly segment the mass region from the location ROIs with an improved vector field convolution (VFC) snake and following extract features from the mass region and its surroundings, and then establish features database with 32 dimensions; finally, these features are used as input to several classification techniques. In our work, the random forest is used and compared with support vector machine (SVM), genetic algorithm support vector machine (GA-SVM), particle swarm optimization support vector machine (PSO-SVM), and decision tree. The effectiveness of our method is evaluated by a comprehensive and objective evaluation system; also, Matthew’s correlation coefficient (MCC) indicator is used. Among the state-of-the-art classifiers, our method achieves the best performance with best accuracy of 97.73 %, and the MCC value reaches 0.8668 and 0.8652 in unique DDSM database and both two databases, respectively. Experimental results prove that the proposed method outperforms the other methods; it could consider applying in CAD systems to assist the physicians for breast cancer diagnosis. 相似文献
996.
Clint L. Miller Amy R. Kontorovich Ke Hao Lijiang Ma Conrad Iyegbe Johan L.M. Björkegren Jason C. Kovacic 《Journal of the American College of Cardiology》2021,77(20):2531-2550
In this second of a 5-part Focus Seminar series, we focus on precision medicine in the context of vascular disease. The most common vascular disease worldwide is atherosclerosis, which is the primary cause of coronary artery disease, peripheral vascular disease, and a large proportion of strokes and other disorders. Atherosclerosis is a complex genetic disease that likely involves many hundreds to thousands of single nucleotide polymorphisms, each with a relatively modest effect for causing disease. Conversely, although less prevalent, there are many vascular disorders that typically involve only a single genetic change, but these changes can often have a profound effect that is sufficient to cause disease. These are termed “Mendelian vascular diseases,” which include Marfan and Loeys-Dietz syndromes. Given the very different genetic basis of atherosclerosis versus Mendelian vascular diseases, this article was divided into 2 parts to cover the most promising precision medicine approaches for these disease types. 相似文献
997.
Relationship between human leukocyte antigen-DRB1 and autoimmune hepatitis type I in Chinese patients 总被引:2,自引:0,他引:2
AIM: To analyze the association of human leukocyte antigen (HLA)-DRB1 with autoimmune hepatitis type I (AIH) among Chinese patients in the Shanghai area. METHODS: In 32 patients and 48 healthy controls, polymerase chain reaction amplified with sequence-specific primers (PCR-SSP) was performed to elucidate the relevance of certain alleles or polymorphic sequences of HLA-DRB1 with autoimmune hepatitis. RESULTS: The HLA-DRB1 typing by PCR-SSP showed that DR4 had a significantly increased frequency among patients with AIH versus that of healthy controls (46.9 vs 20.8%; relative risk = 3.35, P = 0.014). In the subtypes of DR4, there was a trend of an increase in the gene frequency of DRB1*0405 in patients with AIH versus that of healthy controls (21.9 vs 6.3%, P = 0.04, but corrected P (Pc) = 0.08). In addition, our analysis indicated a significant increase in the alleles frequency encoding Leu-Leu-Glu-Gln-Lys-Arg (LLEQRR) from the third hyperpolymorphic region (HVR3) of DR4 in the patients with AIH (86.7% of DR4 positive patients vs 40.0% in DR4 positive controls, P = 0.016, Pc = 0.028, relative risk (RR) = 9.75). CONCLUSION: Type I AIH among Chinese patients is associated with HLA-DR4. There is a relevance of type I AIH and LLEQRR sequence within the third hyperpolymorphic region of the DRB1 allele. 相似文献
998.
999.
Gen Zhang Liang Wu Aitao Tang Bo Weng Andrej Atrens Shida Ma Lei Liu Fusheng Pan 《RSC advances》2018,8(5):2248
In this work, anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. The morphology, structure, and composition of the films were characterized by XRD, SEM, EDS, FT-IR, XPS and GDOES. It was found that the porosity of the films was reduced after in situ fabrication of the LDHs. The effects of boiling water sealing treatment on the anodized substrate were also discussed. Moreover, the polarization curve, EIS, and immersion tests showed that LDHs fabricated on the anodized substrate with boiling water sealing treatment exhibited a significant long period of protection for the substrate.In this work anodized magnesium alloy AZ31 with and without boiling water sealing was pre-prepared, and then MgAl-layered double hydroxide (LDH) films were fabricated on it through hydrothermal chemical conversion of the pre-prepared anodic layer. 相似文献
1000.
Corrosion behaviors of 904L austenitic stainless steel in HF and HCl were studied and compared using electrochemical method, microscopic analysis, and phase analysis. An insoluble layer is deposited on 904L in HF due to a preferential reaction between [F−] and the [Ni] from the alloy. This insoluble deposited layer not only helps isolate the aggressive ions from the base metal, but also inhibits the passivation of 904L in HF, the mechanism for which was entirely different from that in HCl.An insoluble layer is deposited on 904L in HF due to a preferential reaction between [F−] and the [Ni] from the alloy. This insoluble deposit layer helps isolate the aggressive ions from the base metal, while inhibits the passivation of 904L in HF. 相似文献