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901.
Duplicated FoxA genes in the leech Helobdella: Insights into the evolution of direct development in clitellate annelids
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Background: As an adaptation to the land, the clitellate annelid had reorganized its embryogenesis to develop “directly” without the ancestral planktonic larval stage. To study the evolution of gut development in the directly developing clitellates, we characterized the expression pattern of the conserved gut gene, FoxA, in the embryonic development of the leech. Results: The leech has three FoxA paralogs. Hau‐FoxA1 is first expressed in a subset of endoderm cells and then in the foregut and the midgut. Hau‐FoxA2 is expressed in the stomodeum, which is secondarily derived from the anterior ectoderm in the clitellates rather than the tissue around the blastopore, the ancestral site of mouth formation in Phylum Annelida. Hau‐FoxA3 is expressed during the morphogenesis of segmental ganglia from the ectodermal teloblast lineages, a clitellate‐specific trait. Hau‐FoxA1 and Hau‐FoxA2 are also expressed during the morphogenesis of the leech‐specific front sucker. Conclusions: The expression patterns suggested that Hau‐FoxA1 carries out most of the conserved function in the endoderm and gut development, while the other two duplicates appear to have evolved unique novel functions in the directly developing clitellate embryos. Therefore, neofunctionalization and co‐option of FoxA might have made a significant contribution to the evolution of direct development in Clitellata. Developmental Dynamics 247:763–778, 2018. © 2018 Wiley Periodicals, Inc. 相似文献
902.
人体桡神经连续组织切片计算机辅助三维重建研究 总被引:3,自引:0,他引:3
目的:探索一种人体桡神经计算机三维重建的实用方法。方法:采用发丝作为定位材料,将桡神经进行连续组织切片后乙酰胆碱脂酶(acetylchohnesterase,AChE)组织化学染色,高分辨率扫描仪获取二维数码信息后进行三维重建。结果:真实地再现人体桡神经的三维立体结构及桡神经内各神经束的三维立体行径,重建结构均能单独或搭配显示,还能任意角度显示。结论:人体桡神经计算机辅助三维重建方法的图像显示效果较好,是一种较为实用的方法。 相似文献
903.
Yeh YH Chu PH Yeh CH Wu YJ Lee MH Jung SM Kuo CT 《International journal of clinical practice》2004,58(11):1045-1047
Although cardiac tamponade is an important and emergent complication of systemic lupus erythematosus (SLE), purulent pericarditis is rare despite the high frequency of pericardial effusion in SLE. We describe the first SLE case of Haemophilus influenzae type-f pericarditis with cardiac tamponade with SLE as the initial presentation. The pathophysiology and therapy are discussed. 相似文献
904.
Effusion‐based lymphoma with morphological regression but with clonal genetic features after aspiration
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Meng‐Chen Tsai MD Chun‐Chi Kuo MS Ying‐Zhen Su MS Yen‐Chuan Hsieh MS Shih‐Sung Chuang MD 《Diagnostic cytopathology》2018,46(8):685-689
Effusion‐based lymphoma (EBL) is a rare but distinct entity of large B‐cell lymphoma in effusion without association with human herpes virus‐8 (HHV‐8). Spontaneous regression after pleurocentesis has been observed; but to our knowledge, there are no reports on the morphological and molecular features of subsequent aspirations in regressing cases. Here, we report the case of a 92‐year‐old male with chronic obstructive pulmonary disease, who presented with right pleural effusion. He had no human immunodeficiency virus, hepatitis B virus, or hepatitis C virus infection, and CT scans revealed no mass lesion. The first pleural effusion aspiration cytology revealed large lymphoma cells with vesicular nuclei, irregular nuclear contours, and prominent nucleoli, consistent with EBL. The second aspiration cytology showed a few slightly enlarged lymphocytes in a background of small lymphocytes. Immunohistochemical study on cell block of the second aspiration revealed equal amounts of CD3‐positive and CD20‐positive cells. All these cells on the section tested negative for HHV‐8 through immunohistochemistry and Epstein‐Barr virus by in situ hybridization. Our initial impression was EBL in regression. However, flow cytometric immunophenotyping showed monotypic light chain expression of the gated B‐cells. B‐cell receptor gene rearrangement study showed a clonal result. Furthermore, fluorescence in situ hybridization revealed rearrangement of IGH gene. The diagnosis of the second aspiration was EBL with morphological regression but retained clonal genetic features. The patient passed away one month after diagnosis without chemotherapy. This case illustrated the importance of ancillary studies in confirming the clonal nature of a morphologically regressing EBL. 相似文献
905.
P.‐S. Hsieh H.‐C. Tsai C.‐H. Kuo J. Y.‐H. Chan J.‐F. Shyu W.‐T. Cheng T.‐T. Liu 《European journal of clinical investigation》2008,38(11):812-819
Background The effects of cyclooxygenase‐1 (COX1) and cyclooxygenase‐2 (COX2) inhibition on insulin resistance in subjects with the metabolic syndrome remain elusive. Aims of this study were to examine the effects of COX1 and COX2 inhibitors on whole body and muscular insulin resistance in fructose‐fed rats, an animal model of the metabolic syndrome. Materials and methods The rats on regular or 60% fructose‐enriched diets for 6 weeks were further divided into rats combined with or without piroxicam (a selective COX1 inhibitor) or celecoxib (a selective COX2 inhibitor) treatment for an additional 2 weeks. Euglycaemic hyperinsulinaemic clamp (EHC) with a tracer dilution method was performed at the end of the study. Results The present result showed that fructose‐induced increases in systolic blood pressure and fasting plasma insulin levels were significantly suppressed in rats treated with celecoxib but not piroxicam. In the EHC period, celecoxib significantly reversed fructose‐induced decreases in whole body glucose uptake, mainly by glucose storage. Hepatic glucose production and whole body glycolysis were not significantly changed among groups. Celecoxib but not piroxicam significantly reversed fructose‐induced decreases in glycogen synthase activities in red and white quadriceps muscles and insulin‐stimulated membrane GLUT4 recruitment in soleus muscles. Celecoxib and piroxicam both significantly diminished fructose‐induced increases in plasma thromboxane B2 and 6‐keto prostaglandin (PG) F1α; but only celecoxib treatment significantly attenuated a fructose‐induced increase in 8‐isoprostane levels. Plasma PGE metabolites were not different among groups. Conclusions This study demonstrates that a therapeutic dose of celecoxib, but not piroxicam, could significantly attenuate fructose‐induced whole body and muscular insulin resistance in rats. 相似文献
906.
907.
908.
Association of homocysteine level and vascular burden and cognitive function in middle‐aged and older adults with chronic kidney disease
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909.
BACKGROUND AND STUDY AIMS: Bezoars are collections of indigestible foreign material that are found within the gastrointestinal tract. Nonoperative approaches such as dietary therapy, enzymatic dissolution, and endoscopic removal have been regarded as the mainstays of therapy. The purpose of this paper is to determine the efficacy of electrohydraulic lithotripsy (EHL) as an alternative form of treatment of gastric bezoars. PATIENTS AND METHODS: Between July 1988 and May 1996, 11 patients with large gastric bezoars, defined as those greater than 5 cm in diameter, received endoscopic-guided fragmentation using electrohydraulic lithotripsy. Nine of our patients had a history of ingestion of "Pho Pu Zi", (Cordia dichotoma Frost. f.), one of orange pitch, and one of ingestion of persimmon. RESULTS: The 11 patients in the study underwent EHL for the treatment of their gastric bezoars, with a 100% success rate, which was defined as the lack of residual bezoar seen on post-procedure barium study or endoscopy done 2 days after the procedure. Patients were followed-up clinically for 30-68 months, with seven of the 11 patients undergoing a barium study with no residual bezoar noted. No procedure-related complications were seen, except for pharyngeal pain which was most probably secondary to the placement of the silicon overtube. CONCLUSIONS: Endoscopically guided electrohydraulic lithotripsy is a safe, highly effective, alternative nonsurgical technique for the treatment of gastric bezoars. 相似文献
910.
Treatment with mammalian target of rapamycin inhibitors (mTORi) has been associated with an increased incidence of proteinuria after kidney transplantation as compared to other immunosuppressive agents. Proteinuria after mTORi use may occur in different clinical conditions and the precise mechanism remains unclear. The objective of this study was to investigate the related risk factors for proteinuria after mTORi treatment in kidney transplant recipients. This retrospective observational study population consisted of kidney transplant recipients followed up in a medical center in Southern Taiwan from January 1999 to April 2016. The baseline characteristics and transplantation-related profiles were collected at the time of enrollment. We examined risk factors for mTORi-associated proteinuria using a multivariate logistic regression analysis. P < .05 was considered as statistically significant. Hyperlipidemia and obesity at the initiation of mTORi treatment were strong predictors for proteinuria. Earlier identification of these risk factors may assist physicians in deciding the best candidate for mTORi conversion in order to optimize transplantation outcomes. 相似文献