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11.
Differentiation of pancreatic epithelial progenitor cells into hepatocytes following transplantation into rat liver 下载免费PDF全文
Mariana D. Dabeva Seong-Gyu Hwang Srinivasa Rao G. Vasa Ethel Hurston Phyllis M. Novikoff Douglas C. Hixson Sanjeev Gupta David A. Shafritz 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(14):7356-7361
The ability to identify, isolate, and transplant progenitor cells from solid tissues would greatly facilitate the treatment of diseases currently requiring whole organ transplantation. In this study, cell fractions enriched in candidate epithelial progenitor cells from the rat pancreas were isolated and transplanted into the liver of an inbred strain of Fischer rats. Using a dipeptidyl dipeptidase IV genetic marker system to follow the fate of transplanted cells in conjunction with albumin gene expression, we provide conclusive evidence that, after transplantation to the liver, epithelial progenitor cells from the pancreas differentiate into hepatocytes, express liver-specific proteins, and become fully integrated into the liver parenchymal structure. These studies demonstrate the presence of multipotent progenitor cells in the adult pancreas and establish a role for the liver microenvironment in the terminal differentiation of epithelial cells of foregut origin. They further suggest that such progenitor cells might be useful in studies of organ repopulation following acute or chronic liver injury. 相似文献
12.
Twenty-two infants of isolated ventricular septal defect with congestive heart failure were fed with lower-sodium content formula-Lonalac (Mead-Johnson) to study the clinical response of treatment for congestive heart failure. There were no significant changes of intake, urinary output, serum sodium, potassium and osmolality before, 2 days and 6 days after Lonalac feeding. The low sodium content formula may feed the infants with congestive heart failure in addition to the traditional anticongestive therapy. 相似文献
13.
Removing sodium from standard ionic contrastmedia markedly increases the incidence of ventricu-lar fibrillation in patients undergoing coronary arvgiography. Newer nonionic contrast media, Iopa-midol (IOP), Iohexol (IOH) and Ioversol (IOV),contain only trace amounts of sodium. To determinewhether sodium influences the fibrillatory propen-sity of nonionic contrast media, we measured theprolongation in QT interval and performed program-med electrical stimulation with l,2 and 3 ventricularextra stimuli in 40 dogs during 4 ml intracoronaryinjections of IOP, IOH and IOV. Solutions of eachcontrast media with added NaCI at concentrations of0.225To, 0.45% and 0.970 were compared to stockcontrast media. The addition of NaCI markedlyincreased the amount of QT interval prolongationproduced by each contrast media. With IOP, theamount of QT interval prolongation was 40+11msec with standard IOP but was 58+11 msec with0.225'70 NaCI/IOP, 84+17 msec with 0.45'To NaCI/IOP, and 132+42 msec with 0.970 NaCl/IOP(P相似文献
14.
Dong Hwee Kim Yoon Kyoo Kang Miriam Hwang Ho Sung Jo Ki Hoon Kim 《Clinical neurophysiology》2004,115(5):1021-1026
OBJECTIVE: To evaluate the usefulness of the TenElectrodes, a new stimulator for inching test, in the diagnosis and localization of ulnar neuropathy at the elbow (UNE). METHODS: Sixty-two ulnar nerves in 40 control subjects and 24 ulnar nerves in 23 patients with typical symptoms and signs of UNE were studied. The inching test of ulnar motor nerve using TenElectrodes was done along 8 cm across the elbow in the extended position. RESULTS: In the inching test of the control group, the mean segmental latency difference was 0.19+/-0.08 ms. Maximal latency difference over a 1 cm segment did not exceed 0.40 ms in any of the controls but exceeded 0.5 ms or more in all clinical UNE patients. In all UNE patients, the lesion sites were identified by the inching test using TenElectrodes: the retroepicondylar groove (54.2%), the humeroulnar arcade (29.2%), and dual compression (16.6%). CONCLUSIONS: TenElectrodes is a useful stimulator for the inching test in the diagnosis of UNE. The precise localization of compression was possible in all patients with UNE and the most common site was the retroepicondylar groove. 相似文献
15.
16.
Bobak A. Ghaheri MD Karen J. Fong MD Peter H. Hwang MD 《Otolaryngology--head and neck surgery》2006,134(6):1006-1009
OBJECTIVE: The surgical treatment of epistaxis associated with hereditary hemorrhagic telangiectasia (HHT) is varied. Laser therapy is often inadequate for larger complex lesions. This study sought to determine if bipolar cautery can be effectively and safely used in treating HHT-associated epistaxis. STUDY DESIGN AND SETTING: Records from all patients with HHT treated surgically over 8 years were reviewed retrospectively. Outcomes or complications were noted in the clinic on follow-up evaluation. RESULTS: Twenty-seven patients with HHT who underwent surgical treatment of epistaxis were evaluated; 18 were treated with bipolar cautery. Forty-two separate bipolar treatments were performed. No new septal perforations or synechiae were noted. Twenty-two of 42 treatments were coupled with ancillary laser treatments. The bipolar was also used as the sole technique in 20 procedures. CONCLUSION: Bipolar electrocautery is a safe and effective tool for the intraoperative control of HHT-related epistaxis. SIGNIFICANCE: Bipolar electrocautery may be used as an adjunct to laser techniques or as a stand-alone technique. EBM RATING: C-4. 相似文献
17.
M. Wen-Der Yun C. F. Hwang C. C. Lui 《European archives of oto-rhino-laryngology》1991,248(7):422-424
Summary Cavernous sinus thrombosis (CST) is rarely seen clinically as a complication of infectious processes since the discovery of penicillin. At the present time, dental abscess is an uncommon cause of CST. We now report our experiences with a 60-year-old diabetic male, who developed CST 38 days after extraction of an infected upper third molar tooth. The importance of eradicating regional cervicofacial foci of infection is stressed. 相似文献
18.
Paralytic toxicity was detected by tetrodotoxin (TTX) bioassay in all 15 specimens of the xanthid crab Lophozozymus pictor collected from northern Taiwan in 1993. The average toxicity of crab specimens was 921 ± 231 (mean ± S.E.) mouse units. The toxin of crab was partially purified and then identified. It was found that the crab toxin contained TTX and gonyautoxin. The ratio of TTX to gonyautoxin for crab toxin was about 9:1. 相似文献
19.
Computer algorithms for rotational therapy beams, in most cases, perform dose calculations by summing stored fixed beam data at finite angular steps. Such an algorithm, based on the Bentley beam model, was evaluated by comparing calculations with measured data for an 18-MV x-ray beam. Measurements were made in a specially constructed cylindrical water phantom of 15-cm radius using a 0.1-cm3 ionization chamber for an arc of 180 degrees and for a field size of 7.2 X 7.2 cm2 at 100-cm source-axis distance. This study revealed that the Bentley beam model, with fixed beams summed every 10 degrees, predicts the dose in the treatment volume, centered about the isocenter, with an accuracy of approximately 2%. However, dose at depths between the phantom surface and the treatment volume could be underestimated by as much as 10% (3% of isocenter). This was shown to be partially due to the truncated tails of the off-axis profiles in the Bentley model, which extend only 8 mm outside the edge of the radiation field, and the large angular increment of integration (10 degrees). Using beam profiles extending to 4 cm outside the edge of the radiation field and angular steps of 5 degrees or less for summation of fixed beams reduced errors to less than 5%. Therefore, extended beam profiles and smaller angular steps for summing fixed beams are recommended for photon rotation calculation when increased accuracy is required. 相似文献
20.
Background. Malignant changes in burn scars occasionally develop, the majority being squamous cell carcinoma. Malignant melanomas (MMs) arising in burn scars occur rarely.
Objective. To present the case of a patient with a multiple MM developed at different burn scar areas.
Methods. A case report and review of literature are given.
Results. One was a large pigmented nodular lesion with central ulceration on right flank. It was widely excised and revealed lentigo MM. After that, we took notice another small pigmented lesion on right arm. It was also reported lentigo MM.
Conclusion. This case provided a valuable lesson. Another kind of tumor may be present even if one tumor is found by pathologic observation, especially in burn scar patients. Clinicians should carefully observe burn scars, chronic ulcers, and other pigmented lesions. 相似文献
Objective. To present the case of a patient with a multiple MM developed at different burn scar areas.
Methods. A case report and review of literature are given.
Results. One was a large pigmented nodular lesion with central ulceration on right flank. It was widely excised and revealed lentigo MM. After that, we took notice another small pigmented lesion on right arm. It was also reported lentigo MM.
Conclusion. This case provided a valuable lesson. Another kind of tumor may be present even if one tumor is found by pathologic observation, especially in burn scar patients. Clinicians should carefully observe burn scars, chronic ulcers, and other pigmented lesions. 相似文献