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61.
61Cu was produced by natCo(α, xn)61Cu reaction. 61Cu production yield was 89.5 MBq/μAh (2.42 mCi/μAh) at the end of irradiation (EOI). A simple radiochemical separation method using anion exchange resin and ascorbic acid has been employed to separate the product radionuclide from inactive target material and co-produced non-isotopic impurities. The radiochemical separation yield was about 90%. Radiochemical purity of 61Cu was >99% 1 h after EOI. Final product was suitable for making complex with N2S2 type of ligands. 相似文献
62.
S. S. Schwartz D. L. Horwitz B. Zehfus B. Langer A. R. Moossa G. Ribeiro E. Kaplan A. H. Rubenstein 《Diabetologia》1979,16(3):157-164
Summary An artificial beta cell has been used to achieve and maintain a preset plasma glucose concentration in five diabetic patients undergoing surgery. These subjects were compared to control groups of normal subjects receiving either saline or glucose, and diabetics receiving glucose intraoperatively. Hyperglycaemia during surgery was seen in normals (mean plasma glucose ± SEM: 185±16 mg/dl) and, to a greater degree, diabetics (247±36 mg/dl) receiving glucose. Insulin and C-peptide levels did not increase during 2 hours of operation in any of the control groups, suggesting beta cell suppression during surgery. As C-peptide levels declined similarly in normal subjects whether they received saline or glucose, the hyperglycaemia seems to be due to an inability to use exogenous glucose. This is confirmed by a correlation of maximal plasma glucose to glucose infusion rate (r = 0.78, p<0.01). The artificial beta cell was able to achieve the same plasma glucose after 2 hours of operation (128±21 mg/dl) as normal subjects receiving saline (110±7 mg/dl). The artificial beta cell proved to be a safe, convenient and effective way of monitoring and controlling the hyperglycaemia seen in diabetic patients undergoing surgery. 相似文献
63.
《Clinics and research in hepatology and gastroenterology》2022,46(8):101968
ObjectivesThe accuracy of non-invasive liver fibrosis diagnosis based on the apparent diffusion coefficient (ADC) value combined with the γ-glutamyl transpeptidase-to-platelet ratio (GPR) model to predict the stage of hepatitis B-related fibrosis has not been reported. This study aimed to evaluate the diagnostic efficacy of ADC value combined with GPR for liver fibrosis grading.MethodsThe data of 180 patients with chronic hepatitis B (CHB) diagnosed by liver biopsy were analyzed. The ADC value, GPR, and their combination were assessed in different cirrhosis stages using receiver operating characteristic curve analysis to evaluate their value in diagnosing liver fibrosis.ResultsWe observed that liver fibrosis stages were inversely associated with ADC values (r=?0.691, P<0.001), and positively associated with GPR (r=0.502, P<0.001). The area under the curve for diagnostic efficacy of ADC values, GPR, and their combination for F≥2 liver fibrosis was 0.831, 0.749, and 0.858, respectively, and for F≥3 was 0.872, 0.771, and 0.903, respectively. The diagnostic cutoffs of the combination for each stage were -7.07, -12.21 and -37.75, respectively.ConclusionsThe combined diagnostic tool of ADC and GPR may improve the accuracy of hepatitis B-related liver fibrosis diagnosis, especially for F≥3. 相似文献
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Bovine papillomaviruses have a major contribution to make in unravelling the mechanisms of oncogenesis by this group. Most papillomaviruses can exert their biologic effect only in vivo, but several of the bovine types transform fibroblasts in culture; the altered cells have measurable attributes such as anchorage independence, density inhibition, and tumorigenicity in nude mice. Another important feature is that subgenomic fractions of DNA can be transfected into cells and elicit transformation. It is, therefore, possible to undertake quantitative molecular biologic and genetic studies in a way which is impossible with most papillomaviruses. Large amounts of virus can be obtained from bovine tumors. The six currently characterized viruses have all been cloned by recombinant techniques, and are the subject of intensive comparative research in many laboratories. 相似文献
70.
In normal, young miniature piglets, either the major arteries and the veins were ligated or three quarters of the spleen was resected using three different techniques. These techniques served as an animal model for splenic salvage in human subjects. After arterial ligation, no signs of infarction could be seen 1 and 4 weeks later, and after 6 months, normal sized spleens with enlarged vessels in the gastrolienal ligaments were found. When the splenic remnant was left at the main vessels, no obvious growth could be demonstrated after 6 months. The splenic tissue left at the smaller vessels, however, increased in size. Measurements of splenic blood flow in unanesthetized piglets 6 months after operation resulted in greater differences in perfusion per gram among the experimental groups. Not only splenic mass, but also blood flow to the whole splenic tissue seems to be an important factor in the protective function of the spleen. 相似文献