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991.
992.
A One–Step, Operator–Independent Method for Isolating Islets of Langerhans from the Porcine Pancreas
Christophe Arbet–Engels Sylviane Darquy Frédérique Capron Maria E. Pueyo Sophie Dimaria Vincent Poitout Gérard Reach 《Artificial organs》1994,18(8):570-575
Abstract: Large–scale isolation of islets of Langerhans is one of the major obstacles in islet transplantation. Until now, isolation methods relied on enzymatic digestion, the duration of which relies on a decision dictated by the operator's experience. This approach has always hindered development of an automated method. The aim of this study was to develop a one–step method based on complete digestion of the pancreas. The original aspect of the technique (derived from the Ricordi method) is use of the University of Wisconsin (UW) solution in the digestion medium and a continuous flow collagenase processing circuit with local cooling and rewarming to allow tissue digestion to proceed at 37°C while settling of the cell suspension takes place at 4°C. A stopcock system permits the alternate use of two settling chambers so that while one is in the circuit, the other can be removed for cen–trifugation, resuspension of the crude islet preparation in collagenase in free UW solution, and further purification in a density gradient system. Ten experiments were performed, and 545, 750 ± 48, 670 purified pig islets were obtained per totally digested pancreas. Histological studies showed cell integrity. Insulin secretion in response to double glucose stimulation under perfusion conditions demonstrated the functional viability of the isolated islets. In conclusion, this one–step method makes it possible to obtain a high number of viable islets of Langerhans in the absence of any decision by an operator, and it should therefore provide basis for an automated method. 相似文献
993.
M. NISKANEN A. KARI P. NIKKI E. IISALO L. KAUKINEN V. RAUHALA E. SAARELA 《Acta anaesthesiologica Scandinavica》1994,38(6):587-593
Prognostic factors determining the outcome from intensive care were studied in 952 patients admitted to 25 Finnish ICUs after gastroenterologic emergency. Logistic regression analysis was used to create predictive models based on the APACHE II–system. The models were constructed by using data from a random two–thirds of the study population and validated in the remaining independent one–third together with the original APACHE II–index. The Acute Physiology Score, age, and a pre–existing liver disease were the three most important determinants of outcome. The inclusion of the TISS score describing the intensity of treatment into a model did not enhance the accuracy of the prediction. Our models were better calibrated than the original APACHE II–equation when tested by the goodness–of–fit –statistics. These statistical models may help the clinicians to predict the outcome for an individual patient by providing them information about the relative impacts of predictive factors or about the probability of death. These probabilities should be interpreted cautiously, taking into acount the limitations of statistical methods. This is especially important when assessing the highrisk patients. Their number in our study was too low for accurate outcome prediction. 相似文献
994.
995.
Tokio Yamaguchi Masahiko Miyata Wataru Kamiike Yasushi Kobayashi Hikaru Matsuda 《Surgery today》1997,27(5):420-428
To clarify the histological status of the pancreas tail after pancreatoduodenectomy (PD), fibrosis, islets of Langerhans,
and A, B, and D cells were examined histometrically in surgical cases of pancreatic cancer. The same investigations were also
performed during an autopsy examination of the pancreas tail of survivors of surgery who had received either PD or total pancreatectomy
with segmental autotransplantation (SAT). In the surgical cases, fibrosis and the islet percentage compared with nonpancreatic
cancer cases were significantly higher while the B cell ratio was significantly lower. In addition, in pancreatic cancer patients,
the fibrosis and islet ratio in the group with a blocked pancreatic duct were higher while the B cell ratio was lower than
in the group with an open pancreatic duct. A direct relationship between the islet ratio and the degree of fibrosis, and an
inverse relationship between the B cell ratio and the degree of fibrosis, were thus found. From the autopsy cases, the fibrosis
progressed and the islet ratio increased following PD, but after SAT only the islet ratio increased compared to the time of
surgery. The progression of fibrosis after PD thus suggests the presence of some problems in both the surgical method and
postoperative management. 相似文献
996.
997.
Summary. Max Br?del (1870–1941), from Leipzig, Germany, is often referred to in the USA as the father of modern medical illustration
and mentioned in the same breath as Leonardo da Vinci or Andreas Vesal. After a classical formal art education in Leipzig
he worked in Carl Ludwig's laboratory of physiology and anatomy, where he came in contact with American physicians. In 1894,
the anatomist F. P. Mall convinced him to work for the recently inaugurated Johns Hopkins School of Medicine in Baltimore,
where he collaborated with world-famous surgeons such as H. A. Kelly, W. S. Halsted, and H. Cushing. His illustrations were
characterized by meticulous observation, both realistic and explanatory intention, technical superiority, and artistic merit.
In 1911 he established the first “Department of Art as applied to Medicine”. Here, he proved to be an innovative artist, a
creative scientist, and an inspiring and skillful instructor. By the time of Br?del's retirement in 1939, 160 students had
graduated as medical illustrators. His pupils spread his principles and style throughout the USA and Canada, and several similar
academic programs for medical illustration have been founded in these countries.
相似文献
998.
Summary. A prevalence study of Ureaplasma urealyticum (UU) infection of the male genital tract was carried out in Shanghai between March 1992 and June 1995. Significantly higher frequency of UU infection was found among infertile males (549/1416) as compared to fertile controls (34/375). Examination of 8 specimens each from infertile men and fertile subjects by electron microscopy, immunogold and immunofluorescence techniques, demonstrated adhesion of Ureaplasma urealyticum to the membrane of spermatozoa and exfoliated germ cells. In addition, gold particles on Ureaplasma urealyticum were found to be adhered to the sperm surface in 4 of the 8 samples. Strong specific anti-UU fluorescence was detected in 6 of 8 samples, mainly on the midpieces and post-acrosomal regions of the spermatozoa.
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
999.
1000.
聚合酶链反应(PCR)对单纯疱疹病毒性脑炎的临床诊断价值 总被引:2,自引:1,他引:1
应用聚合酶链反应(PCR)检测技术对118例颅内感染性疾病患者及37例无神神经系统疾病患者脑脊液(CSF)中的单纯疱疹病毒DNA(HSV-DNA)进行了检测及分型。结果提示:“散发性脑炎”组的阳性率为38.46%(20/52),细菌、真菌性脑膜炎、其它病毒性脑炎组以及无神经系统疾病组均为阴性。作者认为:①本检测是目前单纯疹病毒性脑炎(HSE)较为简便而准确的早期诊断方法之一;②HSV分型检测,对病原诊断更具有全面性;③两型单纯疱疹病毒均可引起HSE。 相似文献