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61.
Tetranectin, a plasminogen-binding protein with a C-type lectin domain, is found in both serum and the extracellular matrix. In the present study we report that tetranectin is closely associated with myogenesis during embryonic development, skeletal muscle regeneration, and muscle cell differentiation in vitro. We find that tetranectin expression coincides with muscle differentiation and maturation in the second half of gestation and further that tetranectin is enriched at the myotendinous and myofascial junctions. The tetranectin immunostaining declines after birth and no immunostaining is observed in normal adult muscle. However, during skeletal muscle regeneration induced by the intramuscular injection of the myotoxic anesthetic Marcaine, myoblasts, myotubes, and the stumps of damaged myofibers exhibit intense tetranectin immunostaining. Tetranectin is also present in regenerating muscle cells in dystrophic mdx mice. Murine C2C12 myogenic cells and pluripotent embryonic stem cells can undergo muscle cell differentiation in vitro. Tetranectin is not expressed in the undifferentiated myogenic cells, but during the progression of muscle differentiation, tetranectin mRNA is induced, and both cytoplasmic and cell surface tetranectin immunostaining become apparent. Finally, we demonstrate that while tetranectin mRNA is translated to a similar degree in developing limbs and lung, the protein does not seem to be tissue associated in the lung as it is in the limbs. This indicates that in some tissues, such as the limbs, tetranectin may function locally, whereas in other tissues, such as the lung, tetranectin production may be destined for body fluids. In summary, these results suggest that tetranectin is a matricellular protein and plays a role in myogenesis.  相似文献   
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The treatment and prognosis of patients suffering from penis carcinoma who were admitted at the department of radiotherapy of the Kantonsspital Zürich during the last ten years are reviewed. Based on these results which are similar to the results of other centers, we were able to show that primary radiation therapy is to be preferred regarding organ function and survival. Only is a few cases surgical intervention for recurrency was necessary. Indications for radiation therapy of lymph nodes are discussed. The five-year survival rate following primary radiation therapy amounts to 70 or 80% with early stages, a secondary surgical treatment being necessary in 5 to 20%. In more or less advanced stages, a five-year survival rate of 40 to 60% is found after primary radiation therapy, and secondary surgical treatment is needed in 20 to 50%. Thus, survival rates obtained by primary radiation therapy which was followed by an operation only in case of recurrences or tumor persistence are comparable to the recovery rates from primary surgical methods. The advantage of primary radiation therapy is evident in comparison with a surgical treatment: The organ is often saved while the survival rate is the same.  相似文献   
63.
Six cases of benign primary epididymal tumor have been investigated in our patients. The tumor size fluctuated between 3 and 35 mm in diameter. Frequency, histology and medical development are described. The majority of epididymal tumors (53%) is comprised of so-called adenomatoid tumors of benign nature and their histogenesis is being discussed. The difficulties of differential diagnosis are pointed out. Since malignity exists in 26% of the cases, the surgical exposure and diagnosis by frozen section is being postulated, when suspicion of epididymal tumor becomes evident.  相似文献   
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This part of the study points out that concepts such as service to others, the need for regular working hours, financial security and independence have different meanings for different people. What is ultimately shown however, is that despite group and meaning differences, motives for a career choice in dentistry appear to operate on two levels. The first is on the level of the rational and the conscious and the second on the level of the irrational and the subconscious. Knowledge of this process has important implications for the selection and training of students.  相似文献   
65.
Optimal control problems involve the difficult task of determining time-varying profiles through dynamic optimization. Such problems become even more complex in practical situations where handling time dependent uncertainties becomes an important issue. Approaches to stochastic optimal control problems have been reported in the finance literature and are based on real option theory, combining Ito’s Lemma and the dynamic programming formulation. This paper describes a new approach to stochastic optimal control problems in which the stochastic dynamic programming formulation is converted into a stochastic maximum principle formulation. An application of such method has been reported by Rico-Ramirez et al. (Computers and Chemical Engineering, 2003, 27, 1867) but no details of the derivation were provided. The main significance of this approach is that the solution to the partial differential equations involved in the dynamic programming formulation is avoided. The classical isoperimetric problem illustrates this approach.  相似文献   
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OBJECTIVE: To determine whether long-term very vigorous endurance training prevents hypertension. DESIGN: Cohort study of master orienteering runners and controls. SETTING: Finland. SUBJECTS AND METHODS: In 1995, a health questionnaire was completed by 264 male orienteering runners (response rate 90.4%) who had been top-ranked in competitions among men aged 35-59 years in 1984, and by 388 similarly aged male controls (response rate 87.1%) who were healthy at the age of 20 years and free of overt ischemic heart disease in 1985. MAIN OUTCOME MEASURE: Self-report of medication for hypertension. RESULTS: In the endurance athlete group, the crude prevalence (8.7%) of subjects who had used medication for hypertension was less than a third of that in the control group (27.8%). Even after adjusting for age and body mass index, the difference between the groups was still significant (odds ratio for athletes 0.43, 95% confidence interval 0.25-0.76). CONCLUSIONS: Long-term vigorous endurance training is associated with a low prevalence of hypertension. Some of the effect can be explained by a lower body mass, but exercise seems to induce a lower rate of hypertension by other mechanisms than by decreasing body weight  相似文献   
68.
A total of 135 symptomatic women with 262 breast implants were examined with magnetic resonance (MR) imaging performed with a body coil, ultrasound (US), or both to determine imaging features of implant rupture. Surgical proof was available for 33 women with 62 implants; 24 were ruptured and 38 were intact. Complicated internal structure was the most reliable predictor of implant rupture: Diffuse low-level echoes were seen on sonograms in 56% of ruptured implants; internal membranes (which correspond to the collapsed implant shell) were seen on MR images in 58% of ruptured implants. Fluid droplets were seen within the silicone in 26% of ruptured implants on MR images. Irregular implant contour can be a sign of rupture but is unreliable. Fluid collections around silicone implants are not a sign of rupture. At present, neither US nor conventional MR imaging with a body coil is sufficiently reliable to advocate routine screening of asymptomatic women with breast implants. Evaluation with MR imaging performed with a surface coil is more reliable.  相似文献   
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