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51.
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Abstract— Twenty-nine autopsy specimens of intracerebral tumours (nine astrocytomata, ten medulloblastomata and ten glioblastomata multiforme), as well as samples of peritumoral and apparently normal brain tissue, have been studied for Na, K, P, Ca, Mg, Cu, and S contents.
The tumour tissue, irrespective of the histological characteristics, as compared to the 'normal' and perineoplastic tissues, showed higher concentration of Ca, Mg, Cu and S. The peritumoral tissue, regardless of the tumour type, showed a higher concentration of Cu than the 'normal' control brain.
The more malignant glioblatomata and medulloblastomata. The Cu levels did not show a significant diference.  相似文献   
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The treatment of gas gangrene has been revolutionized by oxygen drenching of tissues infected with Clostridia. This was used in a massive infection of the abdominal wall following a traumatic abortion attempt. The clostridial infection was controlled, but the patient almost succumbed to a secondary infection of gram-negative organisms. This responded to drainage, antibiotics and general supportive measures. In the course of treatment, the value of a team approach to complicated special problems was documented.  相似文献   
55.
Essential oil of clove, dispersed (0.4%v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and Candida albicans. Staphyloccus aureus (five strains), Klebsiella pneumoniae, Pseudomonas aeruginosa, Clostridium perfringens , and Escherichia coli inoculated at a level of 107 cfu/ml, and C. albicans (inoculum 4.0×105 cfu/ml) were killed (< 99.999%) after 2–7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4% (v/w) of essential oil of clove. Added organic matter (i.e. human or bovine serum) did not impair its antimicrobial activity.
Sugar was not necessary for the antimicrobial activity of clove oil, but the concentrated sugar solution provided a good vehicle for obtaining an oil dispersion that is relatively stable for certain practical applications.  相似文献   
56.
Brain Cell Biology - The effects of a prolonged blockade of nerve conduction by tetrodotoxin on frog motor innervation were studied in the cutaneous pectoris muscle ofRana esculenta. Prolonged...  相似文献   
57.
To study the CD4+ and CD8+ tumor infiltrating lymphocytes (TIL) in the antitumor response, we propagated these subsets directly from tumor tissues with anti-CD3:anti-CD8 (CD3,8) and anti-CD3:anti-CD4 (CD3,4) bispecific mAb (BSMAB). CD3,8 BSMAB cause selective cytolysis of CD8+ lymphocytes by bridging the CD8 molecules of target lymphocytes to the CD3 molecular complex of cytolytic T lymphocytes with concurrent activation and proliferation of residual CD3+CD4+ T lymphocytes. Similarly, CD3,4 BSMAB cause selective lysis of CD4+ lymphocytes whereas concurrently activating the residual CD3+CD8+ T cells. Small tumor fragments from four malignant melanoma and three renal cell carcinoma patients were cultured in medium containing CD3,8 + IL-2, CD3,4 + IL-2, or IL-2 alone. CD3,8 led to selective propagation of the CD4+ TIL whereas CD3,4 led to selective propagation of the CD8+ TIL from each of the tumors. The phenotypes of the TIL subset cultures were generally stable when assayed over a 1 to 3 months period and after further expansion with anti-CD3 mAb or lectins. Specific 51Cr release of labeled target cells that were bridged to the CD3 molecular complexes of TIL suggested that both CD4+ and CD8+ TIL cultures have the capacity of mediating cytolysis via their Ti/CD3 TCR complexes. In addition, both CD4+ and CD8+ TIL cultures from most patients caused substantial (greater than 20%) lysis of the NK-sensitive K562 cell line. The majority of CD4+ but not CD8+ TIL cultures also produced substantial lysis of the NK-resistant Daudi cell line. Lysis of the autologous tumor by the TIL subsets was assessed in two patients with malignant melanoma. The CD8+ TIL from one tumor demonstrated cytotoxic activity against the autologous tumor but negligible lysis of allogeneic melanoma targets. In conclusion, immunocompetent CD4+ and CD8+ TIL subsets can be isolated and expanded directly from small tumor fragments of malignant melanoma and renal cell carcinoma using BSMAB. The resultant TIL subsets can be further expanded for detailed studies or for adoptive immunotherapy.  相似文献   
58.
Serotypes and antibiotic resistance of 51 Verotoxigenic (VTEC) and 33 Necrotizing (NTEC) bovine Escherichia coli strains were determined and compared with those shown by 205 non-VTEC non-NTEC strains isolated from the same batch of calves. E. coli untypable for O-antigen represented 47% of the VTEC, 12% of the NTEC and 8.8% of the non-VTEC non-NTEC. Typable VTEC belonged to serotypes 02:K?, 0103:K-, 0104:K?, 0128:K?, 0153:K- and O157:K-:H7, whereas typable NTEC were of serotypes 08:K87, 015:K14, 015:K-, 054:K?, 076:K-, 078:K(80), 088:K?, 0123:K-, 0139:K- and 0153:K-. Non-VTEC non-NTEC showed a wide variety of serotypes which were generally unrelated to those found in VTEC and NTEC. VTEC were resistant to antibiotics at higher rates than NTEC and non-VTEC non-NTEC, and showed also the highest multidrug-resistant pattern. Our results show that bovine VTEC strains belonged to O-groups usually found in human VTEC causing sporadic diarrhoea, haemorrhagic colitis and/or haemolytic uraemic syndrome, such as 02, 0103, 0104, 0153 and especially 0128 and O157. In contrast, bovine NTEC strains belonged to serotypes different from those previously found in necrotizing E. coli strains of human origin.  相似文献   
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In an attempt to extend our knowledge of the biology of feeding of the ciliateTetrahymena thermophila, this organism was grown axenically on complex organic material. The nutrient substrate was based on autoclaved wheat grains and adjusted to either pH 5.5 or 7.5. In wild type cultures the cells grew and multiplied only under acidic conditions. In cultures of a mutant cell line blocked in the secretion of acid hydrolases the cells did not grow at either pH value. Thus released acid hydrolases may play a key role in the utilization of complex nutrients in combination with uptake of small organic molecules. Mechanisms in the feeding biology ofTetrahymena thermophila andParamecium tetraurelia are compared.  相似文献   
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