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111.
肝肾胰器官簇移植临床解剖学研究 总被引:1,自引:3,他引:1
目的:为了开展肝肾胰器官簇移植提供应用解剖学资料和术式设计方案。方法:对24具成人尸体进行解剖观察,了解其主要血管分布,胆管、输尿管、胰管的位置以及腹腔内空腔脏器的相互关系。结果:测得主要血管腹主动脉平均长度19.20cm,上端外径2.21cm;下腔静脉平均长度19.42cm,上端外径2.60cm;门静脉长5.59cm,宽度1.49cm;肝固有动脉长3.85cm,宽0.64cm;胆总管长4.19cm,宽度0.78cm;在输尿管平均长度为27.11cm,右输尿管平均长度为25.93cm。对器管簇移植的整体切取、修整、安放和吻合提供多种方案。结论:肝肾胰器官簇移植手术有应用解剖学依据的可行性,按形态学规律有多种合理的术式设计方案 相似文献
112.
J Hassan S O'Neill L A O'Neill U Pattison D J Reen 《Clinical and experimental immunology》1995,102(1):192-198
Accessory molecules play a crucial role in the development of the T cell response to antigenic challenge. We have examined the role of CD28 in modulating the 'naive' neonatal T cell response to anti-CD2-mediated activation. To compare the role of CD28, neonatal and adult T cells were stimulated with a pair of mitogenic anti-CD2 antibodies in the presence or absence of anti-CD28 MoAb. With anti-CD2 alone, neonatal T cells proliferated slightly but produced no detectable IL-2, whereas adult T cells proliferated vigorously, with significant IL-2 production. Costimulation with anti-CD28 MoAb greatly enhanced the proliferative response of neonatal T cells to levels equivalent to those of adult T cells, whereas adult T cells showed only slight increases. Although IL-2 secretion was increased in the presence of anti-CD28 MoAb, neonatal T cell IL-2 production remained lower than in adults. In contrast, enhancement of IL-2 mRNA expression in neonates was similar to adult levels. Anti-CD28 MoAb costimulation increased NF kappa B levels in neonates, albeit to levels lower than that of adults. The cellular mechanism governing the diminished proliferative response of neonatal T lymphocytes to anti-CD2 may therefore be due to decreased NF kappa B induction, reduced IL-2 mRNA expression and deficient IL-2 production. Although anti-CD28 MoAb costimulation enhances all of the above signals, NF kappa B and IL-2 levels remain lower than in adults, suggesting the need for further activation requirements in the neonate. 相似文献
113.
Rodríguez F Ramírez GA Sarradell J Andrada M Lorenzo H 《Journal of comparative pathology》2004,130(4):306-312
Mycoplasma hyopneumoniae (Mh) is the primary agent of porcine enzootic pneumonia (PEN), a chronic respiratory disease endemic to pig farms, and characterized histologically by infiltration of mononuclear cells in airways and prominent hyperplasia of the bronchus-associated lymphoid tissue (BALT). To gain further insight into the pathogenesis of PEN, cytokine expression in the lung, with particular attention to the BALT, was examined immunohistochemically in pigs naturally infected with Mh. An increase (P < 0.05) in proinflammatory and immunoregulatory cytokines (especially interleukin [IL]-2, IL-4 and tumour necrosis factor [TNF]-alpha, and to a lesser extent IL-1 [alpha and beta] and IL-6) was detected in the BALT, which showed intense lymphoid hyperplasia. IL-1beta and TNF-alpha were also detected in the bronchoalveolar exudate of infected pigs, and IL-6 and IL-8 were demonstrated in mononuclear cells of the alveolar septa. The results showed that in Mh infection, macrophage and lymphocyte activation results in the expression of a number of cytokines capable of inducing lung lesions and lymphoreticular hyperplasia of the BALT. 相似文献
114.
Doris Škorić‐Milosavljević Fleur V. Y. Tjong Julien Barc Ad P. C. M. Backx Sally‐Ann B. Clur Karin van Spaendonck‐Zwarts Roelof‐Jan Oostra Najim Lahrouchi Leander Beekman Regina Bökenkamp Daniela Q. C. M. Barge‐Schaapveld Barbara J. Mulder Elisabeth M. Lodder Connie R. Bezzina Alex V. Postma 《American journal of medical genetics. Part A》2019,179(9):1836-1845
The first human mutations in GATA6 were described in a cohort of patients with persistent truncus arteriosus, and the phenotypic spectrum has expanded since then. This study underscores the broad phenotypic spectrum by presenting two patients with de novo GATA6 mutations, both exhibiting complex cardiac defects, pancreatic, and other abnormalities. Furthermore, we provided a detailed overview of all published human genetic variation in/near GATA6 published to date and the associated phenotypes (n = 78). We conclude that the most common phenotypes associated with a mutation in GATA6 were structural cardiac and pancreatic abnormalities, with a penetrance of 87 and 60%, respectively. Other common malformations were gallbladder agenesis, congenital diaphragmatic hernia, and neurocognitive abnormalities, mostly developmental delay. Fifty‐eight percent of the mutations were de novo, and these patients more often had an anomaly of intracardiac connections, an anomaly of the great arteries, and hypothyroidism, compared with those with inherited mutations. Functional studies mostly support loss‐of‐function as the pathophysiological mechanism. In conclusion, GATA6 mutations give a wide range of phenotypic defects, most frequently malformations of the heart and pancreas. This highlights the importance of detailed clinical evaluation of identified carriers to evaluate their full phenotypic spectrum. 相似文献
115.
静电法制备小微囊包裹成年猪胰岛的实验研究 总被引:4,自引:0,他引:4
目的 探索用静电法制备小微囊包裹成年猪胰岛细胞。方法 用自制的静电微囊发生装置、制备海藻酸钠 -多聚赖氨酸 -海藻酸钠 (APA)微囊 (微囊直径 <35 0 μm) ,包裹成年猪胰岛 ,体外检测APA小微囊猪胰岛生物活性及微囊膜的通透性 .结果 静电法制备的APA微囊直径 30 0~ 35 0 μm ,大小相对均一 .小微囊包裹成年猪胰岛后 ,每个微囊内可见 1~ 2个胰岛团 ,表面光滑 .囊内胰岛组织学结构完整 ,体外培养微囊化胰岛素分泌良好 ,葡萄糖刺激释放明显 ,显示了良好的细胞活力及微囊膜通透性 .结论 用我们自制的静电微囊发生装置能制备APA微囊包裹成年猪胰岛细胞 ,微囊直径 30 0~ 35 0 μm ,表面光滑 ,囊内猪胰岛生物活性良好 相似文献
116.
Demonstration of A-currents in pancreatic islet cells 总被引:2,自引:0,他引:2
Paul A. Smith Krister Bokvist Patrik Rorsman 《Pflügers Archiv : European journal of physiology》1989,413(4):441-443
Voltage-activated K+ currents resistant to TEA but blockable by 4-AP were recorded from mouse pancreatic islet cells. These currents first become observable during depolarizations to voltages more positive than –40 mV, reaching a peak amplitude of 120±34 pA at +6 mV (n=4), display rapid turn on (=3.3±1.1 ms at +6 mV) and inactivate completely within 250 ms (=65±5 at +6 mV). The current is subject to steady-state inactivation. The midpoint (V
h) of the inactivation curve (h) was observed at –72±2 mV. The properties of this current resemble those reported for the A-current in neurons. 相似文献
117.
Reiji Haba Shoji Kobayashi Eiichiro Hlrakawa Hiroshi Miki Takeshi Okino Tatsuo Kurokawa Syuu Yamamoto 《Pathology international》1996,46(7):515-519
An extremely rare case of malignant fibrous histiocytoma In the pancreas Is reported. A 70-year-old man complained of upper abdominal discomfort. A tumor in the head of the pancreas was demonstrated by ultrasonography and computed tomography. The surgical specimen revealed a relatively well demarcated tumor, 9 × 7 × 6.5cm in size. Microscopically, fibroblastic, histiocytic, and muitinucleated giant tumor cells were observed in the myxoid area, but some tumor cells had proliferated in a storiform-pleomorphlc pattern. Immunohtstochemically, some tumor cells were positive for lysozyme, α-1-antitrypsin, α-1-antichymotrypsin, and vimentin. Electron microscopically, tumor cells showed a combination of fibroblastic and histiocytic features. The patient Is currently well with no evidence of recurrence or metastasis 22 months after operation. 相似文献
118.
Stelow EB Woon C Pambuccian SE Thrall M Stanley MW Lai R Mallery S Gulbahce HE 《Diagnostic cytopathology》2005,33(2):100-105
Pancreatic somatostatinoma is a rare pancreatic endocrine neoplasm representing as little as 1% of pancreatic endocrine neoplasms (PENs). The histologic features of this tumor are like those of other PENs, except that it commonly forms acinar structures and often has cells with abundant, granular cytoplasm. We have recently encountered two of these neoplasms sampled by endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA). We discuss the cytologic and immunohistochemical findings of these two cases and the cytologic similarities these neoplasms share with pancreatic acinar-cell carcinoma (PACC). We review the cytologic features of PEN and PACC and discuss the importance of cell block immunohistochemistry in the diagnosis of pancreatic neoplasia sampled by EUS-guided FNA. 相似文献
119.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean
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Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
120.
Radosława Nowak Elżbieta Oknińska‐Hoffmann Agata Skórka Dorota Gieruszczak‐Białek Maria Sawadro‐Rochowska 《American journal of medical genetics. Part A》2001,103(2):144-148
Wiedemann‐Rautenstrauch (neonatal progeroid) syndrome is an autosomal recessive condition with characteristic appearance of premature aging present at birth (aged face, natal teeth, and wrinkled skin). Other features of the syndrome are generalized lipoatrophy with specific fat accumulation in the lateral suprabuttock region, hypotrichosis, macrocephaly (pseudohydrocephalus), and mental retardation. We report on a new case that demonstrates all typical features of the syndrome. The girl is now 16 years and 10 months old and has had follow‐up from birth. We measured terminal restriction fragment (TRF) length to evaluate whether the patient's premature aging process is accompanied by shortening of telomere length in her cultured fibroblasts. Mean TRF of 13.5 kb found in our patient's fibroblasts is not shortened as compared to that of normal fibroblasts. Our results differ from those observed in Hutchinson‐Gilford progeria. © 2001 Wiley‐Liss, Inc. 相似文献