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31.
Cathepsin B, H, L and D activities in liver lysosomes were compared between species. Although cathepsin B and D were detected in bovine, pig, chicken and rat liver, striking species differences were evident for cathepsin H and L. Cathepsin L activity was particularly high in chicken lysosomal extracts, but could not be detected in bovine and pig extracts. Whereas there was no significant cathepsin H activity in bovine extracts, rat liver lysosomal extracts contained large amounts of cathepsin H activity.  相似文献   
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Summary Calcium alginate gel-entrapped cells ofCatharanthus roseus were used to study the production of indole alkaloids in a flow through process. The bioreactor was functional for more than two months and product recovery was analyzed under various operating conditions.  相似文献   
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Virchows Archiv B Cell Pathology - Various parameters of the local cellular response have been studied in 16 laryngeal papillomas from ten patients with recurrent papillomas as well as normal...  相似文献   
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Intestinal brush border vesicles of a Mediterranean sea fish (Dicentrarchus labrax) were prepared using the Ca2+-sedimentation method. The transport of glucose, glycine and 2-aminoisobutyric acid is energized by an Na+ gradient (out > in). In addition, amino acid uptake requires Cl? in the extravesicular medium (2-aminoisobutyric acid more than glycine). This Na+- and Cl?-dependent uptake is electrogenic, since it can be stimulated by negative charges inside the vesicles. The specific Cl? requirement of glycine and 2-aminoisobutyric acid transport is markedly influenced by pH, a change from 6.5 to 8.4 reducing the role played by Cl?. In the presence of Cl?, the Km of 2-aminoisobutyric acid uptake is reduced and its Vmax is enhanced. Cl? affects also a non-saturable Na+-dependent component of this amino acid uptake. Amino acid transport is also increased by intravesicular Cl? (2-aminoisobutyric acid less than glycine). This effect is more concerned with glucose uptake, which can be then multiplied by 2.3. A concentration gradient (in > out) as well as the presence of Na+ in the incubation medium seems to enter into this requirement. This intravesicular Cl? effect is not influenced by pH between 6.5 and 8.4.  相似文献   
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Summary The staining properties of AT-specific dyes Hoechst 33342 and DAPI as revealed by Hoechst 33342/mithramycin and mithramycin/DAPI bivariate human flow karyotype patterns are different for chromosomes rich in heterochromatin. The peak corresponding to chromosome Y of a given cell line is higher on the A/T axis with mithramycin/DAPI staining than with mithramycin/Hoechst. The chromosome 1 was found slightly more fluorescent in mithramycin/DAPI than in mithramycin/Hoechst as judged by the slight displacement of its area on the Hoechst-DAPI axis. The other peaks did not show major differences. On the same flow karyotypes, chromosomal rearrangements were detected.  相似文献   
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Synopsis Recent sampling programs conducted in the estuaries of the Eastmain and La Grande rivers (James Bay) and the Great Whale, Little Whale, Innuksuac and Povungnituk rivers (Hudson Bay) revealed patterns of coregonine fish distribution that differ from previous observations. The relative abundance of cisco, Coregonus artedii, and lake whitefish, C. clupeaformis, varied among rivers but did not reveal a latitudinal cline. Previous sampling programs underestimated the abundance of cisco in the Little Whale River. In addition, cisco was the third most abundant species captured in the Povungnituk River, situated 200 km to the north of the previously proposed northern limit at Innuksuac River. As such, the low abundances of cisco in the Great Whale and Innuksuac rivers cannot be attributed to a physiological inability to cope with a reduced growing season. Immature cisco were almost totally absent from the estuaries of the Hudson Bay rivers following spring breakup whereas immature lake whitefish made up 100% of the catch in the Innuksuac River at the same time of year. Species-specific migration patterns in Hudson Bay that differ from those observed in James Bay and the existence of unique juvenile overwintering rivers are 2 hypotheses proposed to explain the discontinuous age-class distribution of cisco and lake whitefish observed in Hudson Bay.Contribution to the program of GIROQ (Groupe Interuniversitaire de Recherche Océanographique du Québec).  相似文献   
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