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A swine metabolism unit was constructed which permitted separate quantitative collection of urine and feces. The unit was built of wood and proved to be reliable. It was adapted for studies with goats, sheep and young cattle.  相似文献   
13.
The causes of the decreased immune responsiveness in tumor-bearing hosts are incompletely understood. The impact of a decreased immune response in cancer patients on the clinical response in immunotherapy trials has not been evaluated. The present report demonstrates a marked decrease in the therapeutic efficacy of adoptively transferred T lymphocytes obtained from murine hosts bearing tumor for greater than 30 days [late tumor-bearing mice (TBM)] as compared with normal mice and mice bearing tumor for less than 21 days (early TBM). In vitro analysis of the functions of the T lymphocytes from late TBM showed an apparently normal proliferative response to anti-CD3 and IL-2 with adequate lymphokine production from CD4+ cells, but a significant decrease in the cytotoxic function of CD8+ cells. The decreased cytotoxicity was not because of cell-mediated suppression. The expression of granzyme B mRNA was significantly delayed and decreased in magnitude in CD8+ cells from late TBM. Culture supernatants from two unrelated tumor cell lines were able to inhibit the cytotoxic activity of normal CD8+ cells in vitro. The tumor-derived suppressive factor is not transforming growth factor-beta (TGF-beta), but it has not been further characterized. The data suggest that one potential mechanism responsible for immunologic defects in patients with large tumor burdens is a tumor-induced defect that compromises the function of CD8+ effector T cells.  相似文献   
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Summary Growing rats (4 weeks old) were kept for 3 weeks at 11° C and 24° C respectively. The cold-adapted animals showed a significantly higher oxygen consumption (64%). Volume density of subsarcolemmal and interfibrillar mitochondria as well as volume density of fat droplets were estimated in M. soleus and the diaphragm of both groups. In cold-adapted animals, the total volume of mitochondria was significantly increased by 24% in diaphragm and 37% in M. soleus. The volume of subsarcolemmal mitochondria was almost doubled in each muscle, but the volume of interfibrillar mitochondria did not change significantly. The surface of the inner mitochondrial membranes per unit volume of mitochondrion in M. soleus was significantly increased both in interfibrillar and subsarcolemmal mitochondria, whereas the surface of the outer mitochondrial membranes per unit volume of mitochondrion was increased only in the subsarcolemmal mitochondria. The volume of fat droplets in the diaphragm and M. soleus of cold adapted animals increased significantly by 62% and 150% respectively.  相似文献   
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Preliminary studies using an improved method for the agarose gel electrophoresis of semipurified, cleared lysates of staphylococci have indicated some distinct differences in plasmid composition between the coagulase-positive speciesStaphylococcus aureus andStaphylococcus intermedius, and various coagulase-negative species. Penicillinase-positive strains ofS. intermedius andS. simulans did not carry large penicillinase plasmids like most penicillinase-positive strains ofS. aureus. Most coagulase-negative species examined demonstrated complex plasmid profiles. Codigestion by the restriction endonucleasesHaeIII andHpaI offered a useful approach for “fingerprinting” large plasmids from various strains and species.  相似文献   
17.
The two membranes, plasmalemma and tonoplast (Saccharomyces cerevisiae H 1022), are characterized ultrastructurally by their different texture in the corresponding freeze-fracture faces and their silver staining properties.Biochemical characterization with regard to proteins and lipids indicated that the ratio of protein to lipid is significantly higher in the plasmalemma as compared to the tonoplast. Moreover, a pronounced difference appears to exist for both the amount and the composition of total lipids, phospholipids and sterols. The protein patterns of the plasmalemma and the tonoplast reveal only minor differences, as judged by sodium dodecyl sulphate gel electrophoresis.  相似文献   
18.
The autors study 76 human brains, 36 of which are dissected. They observe a "T1 T2 bridge" over the first temporal and second temporal gyri more often on the left side than on the right. They find the maximal width of the superior face of the second temporal gyrus predominant on the right side in 70% of cases, on the left side in 15% and equivalent on both sides in 15%. The fusiform gyrus is found wider on the left side in 53% of cases, on the right in 22% and equivalent on both sides in 25%.  相似文献   
19.
Structural deteriorations in biomembranes, as inevitably induced while structural information is gathered by electron optical methods, were evaluated by infrared spectroscopy. Tripalmitin model membranes were irradiated with 100 keV-electrons in an electron microscope. The intensity decay of group vibrations over the dose reveals the sequence of damage in the polar and nonpolar part of the molecule. The C-C backbone, being the most important structural feature, shows a significant latency effect up to 0.6 e-/A2 and is completely disordered by 3 e-/A2, corresponding to about three inelastic processes per molecule.  相似文献   
20.
Different species from the Achillea millefolium aggregate are used against gastrointestinal and hepato-biliary disorders in traditional European medicine. In this work, a fraction enriched in dicaffeoylquinic acids (DCCAs) and luteolin-7-O-β-d-glucuronide was investigated on its choleretic effect in the isolated perfused rat liver (IPRL) compared to cynarin (1,3-DCCA), the main choleretic compound of Cynara scolymus L. A fraction containing 3,4-, 3,5- and 4,5-DCCA and luteolin-7-O-β-d-glucuronide was prepared by solid phase extraction from a 20% methanolic extract of yarrow. A total amount of 48.8% DCCAs and 3.4% luteolin-7-O-β-d-glucuronide was determined by HPLC analysis with cynarin as internal standard. IPRL experiments revealed a dose-dependant increase in bile flow (23–44–47%) by the Achillea fraction. Choleresis was two- to three-fold higher than that of cynarin. The combined effect of DCCAs and luteolin-7-O-β-d-glucuronide stimulated bile flow more effectively than the single compound cynarin. Due to their polar structure, these compounds are quantitatively extracted into teas and tinctures; hence, they seem to be the choleretic active principles in the traditional application forms of yarrow.  相似文献   
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