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11.
This study was designed to investigate the effect of retaining coronal tooth substance on the performance of post-retained core materials, and to compare the fracture resistance of the system with an intact tooth prepared to similar dimensions. Ten teeth restored with post-retained silver amalgam, and 10 teeth restored with silver-glass cermet, all with a retained single wall of coronal tooth substance, were compared with 10 unrestored teeth prepared to similar dimensions when subjected to a shearing load. The results showed no statistically significant difference between the unrestored teeth and those restored with a silver-glass cermet. Whilst the teeth restored with silver amalgam had a significantly higher fracture resistance (P > 0.01) there was greater tendency to root fracture.  相似文献   
12.
Lameness of the hindlimbs originating from the stifle joint may be difficult to diagnose and treat. This article describes anatomic considerations and the diagnostic procedures necessary to accurately evaluate the bovine stifle joint. The emphasis is toward obtaining a diagnosis based on physical examination and simple diagnostic procedures in field situation. Specific treatments and/or management alternatives for cattle with various ligament injuries (cranial cruciate rupture, collateral ligament injuries), or with luxated patella, upward fixation of the patella, septic arthritis, and subchondral bone cysts are described. Current knowledge of the prognosis after various treatments is presented.  相似文献   
13.
28 isolates of canine parvovirus type-2 (CPV-2) were obtained from dogs with hemorrhagic gastroenteritis in Italy. The antigenic structure of CPV-2 isolates was characterized, using four discriminating monoclonal antibodies. In addition, four vaccinal strains were examined. Similar to reports from Australia and the United Kingdom, a much higher prevalence of CPV-2a (25/28 isolates) was observed than the other variant type, CPV-2b (3/28 isolates). DNA fragments (2.2 kbp) of representative strains of CPV-2, CPV-2a and CPV-2b were amplified by the polymerase chain reaction (PCR) and the products were digested by the restriction enzymes (RE) RsaI, HpaII, HindIII and PvuII. The RvaI enzyme allows the differentiation of CPV-2 from CPV-2a and CPV-2b.  相似文献   
14.
15.
BACKGROUND AND OBJECTIVE: Long-term culture-initiating cells (LTC-IC) are the best available approximation to an in vitro assay of stem cells in humans although they still represent a heterogeneous population in terms of proliferative capacity and sensitivity to different growth factors. Human umbilical cord blood (CB) is rich in hemopoietic progenitor cells, as measured by clonogenic assays and contains stem cells capable of reconstituting the marrow after ablation in clinical transplantation. We evaluated the influence of culture conditions on the in vitro behavior of LTC-IC from CB. DESIGN AND METHODS: LTC-IC were evaluated in long-term cultures, comparing two types of murine stromal cell lines: M2-10B4 and M2-10B4 transfected with cDNAs for human G-CSF and IL-3. RESULTS: Two and five fold higher numbers of terminally differentiated cells were produced during nine weeks of culture of CB mononuclear or CD34+ cells respectively, in cultures containing a M2-10B4 IL-3 G-CSF cell line compared to cultures containing the parental cell line. Likewise, a higher number of colony-forming cells (CFC) were detected in the supernatant of cultures with the transfected cell line. In contrast, the number of CFC generated within the stromal layer, after 5 or 9 weeks of culture, was significantly higher in cultures on M2-10B4 cells than those on M2-10B4 IL-3 G-CSF. INTERPRETATION AND CONCLUSIONS: Our results show that the proliferative capacity of CB LTC-IC can be strongly influenced by culture conditions and that the frequency of LTC-IC estimated using these cell lines as stromal support is not identical.  相似文献   
16.
The response people have to vaccination varies because their immune systems differ and vaccine failures occur. Here we consider the effect that a random response, independent for each vaccinee, has on the vaccination coverage required to prevent epidemics in a large community. For a community of uniformly mixing individuals an explicit expression is found for the critical vaccination coverage (CVC) and the effect of the vaccine response is determined entirely by the mean E(AB), where A and B, respectively, reflect the infectivity and susceptibility of a vaccinated individual. This result shows that the usual concept of vaccine efficacy, which focuses on the amount of protection the vaccine provides the vaccinee against infection, is not adequate to describe the requirements for preventing epidemics when vaccination affect infectivity. The estimation of E(AB) poses a problem because A and B refer to the vaccine response of the same individual. Similar results are found when there are different types of individual, but now the mean E(AB) may differ between types. However, for a community made up of households it is shown that the CVC also depends on other characteristics of the vaccine response distribution. In practice this means that estimating a single measure of vaccine effectiveness is generally not enough to determine the CVC. For a specific community of households it is found that the vaccination coverage required to prevent epidemics decreases as the variation in the vaccine response increases.  相似文献   
17.
PURPOSE: To review the University of Florida experience in treating ependymomas, analyze prognostic factors, and provide treatment recommendations. METHODS AND MATERIALS: Forty-one patients with ependymoma and no metastases outside the central nervous system received postoperative radiotherapy with curative intent between 1966 and 1989. Ten patients had supratentorial lesions, 22 had infratentorial lesions, and 9 had spinal cord lesions. All patients had surgery (stereotactic biopsy, subtotal resection, or gross total resection). Most patients with high-grade lesions received radiotherapy to the craniospinal axis. Low-grade intracranial lesions received more limited treatment. Spinal cord lesions were treated using either partial spine or whole spine fields. RESULTS: Of 32 intracranial tumors, 21 recurred, all at the primary site; no spinal cord tumors recurred. Overall 10-year survival rates were 51% (absolute) and 46% (relapse-free); by tumor site: spinal cord, 100%; infratentorial, 45%; supratentorial, 20% (p = 0.002). On multivariate analysis, tumor site was the only factor that influenced absolute survival (p = 0.0004); other factors evaluated included grade, gender, age, duration of symptoms, resection extent, primary tumor dose, treatment field extent, surgery-to-radiotherapy interval, and days under radiotherapy treatment. CONCLUSIONS: Patients with supratentorial or infratentorial tumors receive irradiation, regardless of grade. Craniospinal-axis fields are used when spinal seeding is radiographically or pathologically evident. Spinal cord tumors are treated using localized fields to the primary site if not completely resected. Failure to control disease at the primary site remains the main impediment to cure.  相似文献   
18.
NG 《电脑》2014,(2):58
正告别"一生",迎来"一世"。新旧交替中,中国车市开启了新的篇章。2013年,在"微增长"的预期下,国内汽车产销双双超过2000万辆,再创全球产销最高纪录,国内私家车保有量进一步提升。在汽车后市场被业内人公认为汽车售后利润增长点的情况下,这  相似文献   
19.
Subdermal superficial liposuction, first presented by the authors at the ISAPS Congress at Zurich in 1989, is performed with thin three-hole Mercedes cannulas (diameter ranges from 1.8 to 2 mm) to treat small and secondary adiposities and to allow better skin retraction. Suction of the subdermal layer of fat reduces the thickness and consistency of the superficial fat and enhances the possibility of skin retraction. In cases where there is a large adiposity of the abdomen, arms, or inner thighs, there is a conspicuous volume of fat whose weight tends to overstretch and to carry the overlying skin downward. In these cases we need to reduce the large fat volume to permit effective skin retraction. Therefore, we apply the principles of traditional liposuction with those of subdermal superficial liposuction to aspirate large amounts of fat from all the adipose layers. We call this technique Massive All Layer Liposuction (MALL). The amount of skin shrinkage after this "defatting" procedure is remarkable and the clinical results are very good. The MALL technique can be applied to other areas as well. In our experience this new liposuction technique has dramatically reduced the indications of abdominoplasties and dermolipectomies of inner thighs and arms.  相似文献   
20.
Electron microscopic study was performed in the experiments on the rat liver while intravenously administering E. coli endotoxin. The dynamics of ultrastructural disorders during endotoxemia has been established and the role of "Kupffer cell-hepatocyte" microsystem in the liver detoxification function is shown.  相似文献   
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