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81.
Using two malignant rat glioma cell lines, we tested to what extent peripheral immunization could affect tumor growth in the brain of syngeneic rats. Peripheral subcutaneous (s.c.) immunization was performed with autologous Newcastle-disease-virus (NDV)-infected or non-infected live tumor cells. Thus immunized rats or non-immunized controls were intracerebrally implanted with increasing numbers of the respective malignant glioma cells. Without immunization the mean survival time after intracerebral implantation of 1x10(4) TZ363 or RG2 glioma cells was 9 and 29 days respectively. After s.c. immunization with either NDV-infected or non-infected TZ363 cells only 25% or less of challenged animals developed tumors in the brain. Immunization with NDV only had no effect. In RG2 glioma, s.c. immunization had no effect on tumor growth in the central nervous system and on survival time, no matter what kind of vaccine was used. These results clearly show, that in principle the efferent arm of the anti-tumor response can be effective accross the blood-brain barrier and extend into the microenvironment of the central nervous system. Whether or not glioma lines can induce this immunity and respond to it, seems to depend on their individual immunobiological characteristics.  相似文献   
82.
The objective of this study was to examine the relationship of nonmedical factors, including socioeconomic status, social class, education, race, and social support, to low birth weight. In a case-control study of all resident very-low-birth-weight births between December 1, 1989, and March 31, 1991, mothers completed an extensive survey related to their experience of pregnancy, including prenatal and postnatal care. Cases were defined as very-low-birth-weight (VLBW) infants and were matched to moderately-low-birth-weight and normal-birth-weight infants in race, age, and maternal residence. The hypothesis that social and class factors are more predictive of low birth weight than medical factors alone for women without chronic health problems was supported. Although the degree of the association varies depending on birth weight outcome, race even though addressed through matching--continued to play an important role in birth outcomes. A comparison of logistic model performance with and without the inclusion of social factors indicated the importance these variables play in prediction of birth outcomes. This is one of the few studies undertaken that explicitly investigates impact of patient factors on medical care.  相似文献   
83.
The purpose of this article is to raise some points for an understanding of the contemporary debate over the ethics of using animals in scientific experiments. We present the various positions from scientific and moral perspectives establishing different ways of viewing animals, as well as several concepts like 'animal ethics', 'animal rights', and 'animal welfare'. The paper thus aims to analyze the importance and growth of this debate, while proposing to expand the academic approach to this theme in the field of health.  相似文献   
84.
Nucleoside analogue-induced lactic acidosis is an often fatal condition in patients with HIV. There is only one report of successful treatment with riboflavin. We describe a 30-year-old female with AIDS and nucleoside analogue-induced lactic acidosis that exacerbated shortly after introducing total parenteral nutrition and reversed within hours after the addition of thiamine. Successful treatment of nucleoside analogue-induced lactic acidosis with a high dose of thiamine supports the hypothesis that vitamin deficiency is an important cofactor in the development of this rare and unpredictable condition in patients with HIV. We suggest that high dose B-vitamins should be given to any patient presenting with lactic acidosis under nucleoside analogue treatment.  相似文献   
85.
Zusammenfassung Bei einem 47 jährigen Patienten entwickelten sich am rechten Bein mehrere rasch wachsende Tumoren von distal nach proximal. Histologisch und elektronenmikroskopisch zeigten die Tumorzellen morphologische Besonderheiten, die für ihre histiocytäre Provenienz sprechen. Auffallend war die große Anzahl polymorpher cytoplasmatischer Membranstrukturen und großer Vacuolen, die massenhaft kleine Vesikel enthielten. Diese Strukturen werden als transformierte multivesiculäre Körper gedeutet; ihre Entstehung vollzieht sich im Rahmen einer bizarr übersteigerten Membranaktivierung einer malignen Zellrasse. Bemerkenswert ist die rasche und völlige Remission durch Radiotherapie.
Multivesicular vacuolization in malignant histiocytoma of the skin
Summary A 47-year-old patient developed several rapidly growing tumours in his right leg. Histologic and electron microscopic examination revealed morphological characteristics suggesting the histiocytic origin of the tumour cells. An important finding was the striking number of pleomorphic membraneous inclusions and large vacuoles containing numerous small vesicles. These cytoplasmic inclusions are interpreted as transformed multivesicular bodies. Their formation may be an expression of an increased and bizarre membraneous activity of a malignant cell race. Radiotherapy resulted in a remarkably rapid and complete remission.


Auszugsweise vorgetragen beim 4th European Meeting on Electron Microscopy Applied on Cutaneous Pathology, Heidelberg, 6. und 7. Mai 1977: Multivesicular Vacuolization in Malignant Histiocytoma.  相似文献   
86.
87.
Zusammenfassung Schwerwiegende thorakale Trachealläsionen können gelegentlich zu einer bedrohlichen Behinderung der Atmung führen, die mit konventionellen Methoden nicht mehr zu beherrschen ist. In einem solchen Beatmungsnotfall erscheint uns der notfallmäßige Einsatz der extrakorporalen Zirkulation zum Zwecke der Abwendung des drohenden Herzstillstandes, der evtl. notwendig werdenden Wiederbelebung und Stabilisierung des Patienten gerechtfertigt und geradezu Voraussetzung für die Trachealrekonstruktion zu sein. Über zwei nach diesem Konzept behandelte Patienten wird berichtet.  相似文献   
88.
The concentration of the metabolite of the beta-blocker metipranolol was determined in the aqueous humour of 89 cataract patients. At 1, 2 or 5 h before surgery, they received one drop (30 l) of a 0.1 % or 0.3% solution of the drug. At 1, 2 or 5 h after the application of 0.1 % metipranolol eye drops, desacetylmetipranolol concentrations of 624.55, 235.29 and 88.02 ng/ ml, respectively, were measured. At the same intervals after the instillation of 0.3% metipranolol eye drops, the respective values of 1289.20, 1120.88 and 327.36 ng/ ml were found. The metabolite concentration in the eye drops and the values measured show no consistent correlation.Offprint requests to: H. Bleckmann  相似文献   
89.
Studies on the mechanisms of transformation of mammalian cells by herpes simplex virus (HSV) in vitro have been prevented so far by the extremely low transformation frequencies obtained in monolayer culture. Here we present a transformation system that relies on the direct seeding in soft agar of infected single cells, thus avoiding negative interactions between normal and transformed cells. We took advantage of HSV-I temperature-sensitive mutants at the UL9 locus, which codes for a DNA-binding protein necessary for viral DNA replication. At the non-permissive temperature, viral DNA synthesis and late gene expression are prevented. Viral gene expression is restricted to immediate early and early genes. Induction of transformation was highly efficient in our one-step transformation system. It depended on intact viral particles and viral DNA. Immediate early and/or early viral gene expression was sufficient to induce transformation. Colonies were stably transformed and did not show any rescue of viable virus after temperature downshift and co-cultivation with susceptible cells. Transformed cells maintained the transformed state in the absence of viral DNA. Our data therefore support the "hit-and-run" hypothesis for the transforming effect of HSV.  相似文献   
90.
The action of calcitonin gene-related pepide (CGRP) was studied on c-fos gene expression in rat astrocyte cultures. A strong and transient increase in c-fos mRNA was observed in cultured astrocytes after treatment with CGRP. Quantitative Northern blot analysis revealed an increase of c-fos mRNA within 15 min, a peak after 30 min with a 10 - 15 fold increase over unstimulated cells and a subsequent decline. Induction of the c-fos gene by CGRP was concentration-dependent, half maximal stimulation of c-fos mRNA being obtained with 100 nM CGRP. The CGRP effect appeared to be mediated by a CGRP receptor and calcitonin was found to mimic only weakly the action of CGRP on cultured astrocytes. Calcitonin transiently induced c-fos gene expression with a similar time course to CGRP, but its effect was much less pronounced. Agents affecting the intracellular cyclic AMP level, forskolin and Ro 20-1724, stimulated c-fos mRNA in a strong and transient fashion with a temporal sequence similar to the response to CGRP. Further, the phosphodiesterase inhibitor Ro 20-1724 potentiated the action of CGRP on c-fos mRNA induction, suggesting a role for cyclic AMP in the action of CGRP. The present results indicate that CGRP may play a physiological role as a regulator of astrocyte gene expression.  相似文献   
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