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101.
Erdheim-Chester disease (ECD) is a rare histiocytosis usually affecting the skeletal system, but visceral organs and central nervous system involvement are common as well. Probability exists that immunomodulatory therapies and disorders can play a role in clinical course of the disease. Because of rarity of the disorder, it is hard to classify it and standardize the treatment options, but, according to published material and our experience, cytotoxic chemotherapy and long-term steroids have therapeutic benefit. Although this approach can probably be accepted as standard of care management, novel therapeutic modalities should be explored, and pathogenesis and disorder classification should be cleared out as well. The case of ECD affecting skeletal system and lungs and concomitant laryngeal tuberculosis successfully treated with chemotherapy and long-term steroid therapy is presented.  相似文献   
102.
In this study, osseous tissue was examined in normal adult population that has inhabited areas by the Croatian Adriatic Sea. The most of such studies have shown that women are prone to lose bone connectedness, while men are predisposed to be a stronger constitution and they start with greater bone mass, though. Bone samples from two different anatomic sites were analyzed. The crista iliaca and the lumbar vertebra represent functionally different organs too. We wanted to consider weather the same age- and gender-related changes affect these two organs due to normal aging. Static histomorphometry was used to quantify involution changes in the trabecular bone. Results showed that involution process more severely affects women than men. Age-related structural changes were more prominent in lumbar vertebra than in iliac crest bone. Severe structural changes in lumbar vertebra could subsequently lead to a dysfunctional and deformed vertebral column. Therefore, iliac crest bone biopsies could hardly explain involution process that affects lumbar spine.  相似文献   
103.
Uptake of Al across the plasma membrane of plant cells   总被引:6,自引:1,他引:6  
Rengel  Zdenko  Reid  Robert J. 《Plant and Soil》1997,192(1):31-35
Measurements of intracellular, cytosolic Al are plagued with technical difficulties. An accurate quantification of Al uptake into the cytosol relies on the effectiveness of the methods that desorb Al bound to the cell wall. However, published desorption methods are not completely effective in removing cell wall Al. Using giant algal cells of Chara corallina, where a physical separation of the cell wall and the cytosol can be achieved surgically, it was shown that up to 99.99% of the total cellular Al accumulates in the cell wall. Even when 95% of total Al present in intact cells was desorbed, still over 20 times more Al was left in the cell wall than in the cytosol. Therefore, without physical separation of the cell wall and the cytosol, minute amounts of cytosolic Al need to be measured in the considerably larger background of the cell wall Al. Consequently, up to several orders of magnitude lower uptake rates of Al were measured across the plasma membrane of intact Chara cells in comparison to currently available values on higher plant cells (Triticum aestivum, t Glycine max, Phaseolus vulgaris), where at least some of the cell wall Al was attributed to the intracellular, cytosolic Al. Uptake of Al across the plasma membrane of Chara cells occurs without a delay at a very low rate that is directly proportional to Al concentration in the uptake medium. Moreover, residual Al left in the cell wall after desorption can be taken up into the cytosol of Chara cells during subsequent growth in the artificial pond water. For measuring Al uptake into roots of higher plants, the Secondary Ion Mass Spectrometry is the best available technique because it appears to overestimate the cytosolic Al to the lower extent than any other currently used analytical method for determination of Al.  相似文献   
104.
Inverted papilloma is an epithelial neoplasm of the lateral nasal wall and adjacent sinuses characterized by a marked propensity for recurrence and a significant association with carcinoma. In this retrospective study we present 31 cases treated by our departments between 1982 and 1999. The aim was to compare our results to those of other authors especially regarding surgical management. The male to female ratio of these patients was 2:1 and most patients were in the 6th and 7th decades of life. Conservative surgery was used in most cases as the initial treatment. The overall recurrence rate was low and there were 3 cases associated with carcinoma. We conclude that the results of conservative surgery in selected cases are comparable to those using radical methods. A review of the literature is presented and particular attention is dedicated to the literature concerning analysis of p53 expression, HPV and Epstein-Barr infection and apoptosis in inverted papilloma.  相似文献   
105.
Photosystem I (PSI) is a multi-subunit integral pigment–protein complex that performs light-driven electron transfer from plastocyanin to ferredoxin in the thylakoid membrane of oxygenic photoautotrophs. In order to achieve the optimal photosynthetic performance under ambient irradiance, the absorption cross section of PSI is extended by means of peripheral antenna complexes. In eukaryotes, this role is played mostly by the pigment–protein complexes of the LHC family. The structure of the PSI-antenna supercomplexes has been relatively well understood in organisms harboring the primary plastid: red algae, green algae and plants. The secondary endosymbiotic algae, despite their major ecological importance, have so far received less attention. Here we report a detailed structural analysis of the antenna-PSI association in the stramenopile alga Nannochloropsis oceanica (Eustigmatophyceae). Several types of PSI-antenna assemblies are identified allowing for identification of antenna docking sites on the PSI core. Instances of departure of the stramenopile system from the red algal model of PSI-Lhcr structure are recorded, and evolutionary implications of these observations are discussed.  相似文献   
106.
Alternate metabolic pathways for the formation of malonylCoA in the actinomycete Streptomyces aureofaciens are examined. Comparison of the specific activities of pyruvate kinase, pyruvate dehydrogenase, and phosphoenol-pyruvate carboxylase during cultivation, the degree of incorporation of individual radioactive substrates into the tetracycline molecule, and the high randomization of acetate-[2-14C], indicate that the malonylCoA used in tetracycline biosynthesis does not appear solely through the carboxylation of acetylCoA. The role of the phosphoenolpyruvate carboxylase and oxaloacetate dehydrogenase systems in the formation of malonylCoA is established, and using radio-GLC, a cell-free preparation of S. aureofaciens mycelium is shown to form malonate from oxaloacetate. The reaction requires HSCoA and NAD+.  相似文献   
107.
Enzymatic milk coagulation for cheese manufacturing involves the cleavage of the scissile bond in kappa-casein by an aspartic acid protease. Bovine chymosin is the preferred enzyme, combining a strong clotting activity with a low general proteolytic activity. In the present study, we report expression and enzymatic properties of recombinant camel chymosin expressed in Aspergillus niger. Camel chymosin was shown to have different characteristics than bovine chymosin. Camel chymosin exhibits a 70% higher clotting activity for bovine milk and has only 20% of the unspecific protease activity for bovine chymosin. This results in a sevenfold higher ratio of clotting to general proteolytic activity. The enzyme is more thermostable than bovine chymosin. Kinetic analysis showed that half-saturation is achieved with less than 50% of the substrate required for bovine chymosin and turnover rates are lower. While raw camel milk cannot be clotted with bovine chymosin, a high clotting activity was found with camel chymosin.  相似文献   
108.
109.
This report describes a chondromyxoid fibroma of the second metacarpal bone in a 32-year-old female patient. Chondromyxoid fibroma is a rare, benign, slow-growing bone tumor of cartilaginous origin. Tumor has a high recurrance rate. Our aim was to show successful treatment of a metacarpal chondromyxoid fibroma with wide resection and implantation of finger join endoprosthesis.  相似文献   
110.
Ten Triticum aestivum and two Triticum turgidum conv. durum genotypes were grown in chelate-buffered nutrient solution at Zn supplies ranging from deficient to sufficient (free Zn activities from 2 to 200 pM, pZn from 11.7 to 9.7). The critical level of Zn ion activity in solution for healthy growth of wheat plants was around 40 pM. Genotypes differed in the growth response: those classified as Zn-efficient suffered less reduction of shoot growth and did not change the rate of root growth at a Zn supply quite deficient for Zn-inefficient genotypes. Root growth of Zn-inefficient genotypes increased at deficient Zn supply. The shoot/root ratio was the most sensitive parameter of Zn efficiency; Zn-efficient genotypes showed less reduction in the ratio when grown at deficient compared to sufficient Zn supply. Classification of wheat genotypes into Zn-efficient and Zn-inefficient groups after screening in chelate-buffered nutrient solution corresponded well with classification obtained in field experiments on Zn-deficient soil.  相似文献   
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