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71.
The effect of two phenothiazines, chlorpromazine (CPZ) and trifluoperazine (TFP) on the copper and endothelial cell-induced peroxidation of low density lipoprotein (LDL) has been studied and compared to that of drugs previously shown to protect LDL against peroxidation: probucol (PBC) and butylated hydroxytoluene (BHT). Incubation with CPZ or TFP inhibited in a dose-dependent manner LDL peroxidation induced either by copper ions or by cultured endothelial cells. Both the electrophoretic mobility and the thiobarbituric reactive substance content of LDL returned to almost normal values in the presence of 50 microM CPZ or TFP. The two studied phenothiazines also strongly inhibited the hydrolysis of LDL phosphatidylcholine which accompanies copper or endothelial cell-induced peroxidation of the particle. CPZ and TFP were as effective as PBC and BHT in inhibiting the LDL peroxidation. Whereas copper or endothelial cell-oxidized LDL were recognized and rapidly catabolized by mouse peritoneal macrophages, CPZ- or TFP-, as well as PBC- or BHT-treated LDL were not. Moreover, it was found that, in contrast to vitamin E, neither CPZ nor PBC reacted with model peroxy radicals formed by gamma irradiation of aerated ethanol. The possible mechanisms underlying this protective effect of phenothiazines against LDL oxidative modification are discussed.  相似文献   
72.
Due to its localisation in the apex of the lung with invasion of the lower part of the brachial plexus, first ribs, vertebrae, subclavian vessels or stellate ganglion, a superior sulcus tumour causes characteristic symptoms, like arm or shoulder pain or Horner's syndrome. If rib invasion is the only feature, lysis of the rib must be evident on the chest radiograph; otherwise the tumour cannot be defined as a Pancoast tumour. It is important to adequately stage the tumour, because staging significantly influences survival. Survival is better for T3 than T4 tumours and mediastinal lymph node involvement has been found to be a negative prognostic factor. Also Horner's syndrome and incompleteness of resection worsen survival. The management of superior sulcus tumours has evolved over the past 50 years. Before 1950 it was considered to be inoperable and uniformly fatal. Shaw and Paulson introduced combined modality treatment and for many years, this combination of radiotherapy and surgery was the treatment of choice with a mean 5-year survival of approximately 30%. Postoperative radiotherapy or brachytherapy does not improve survival in patients with complete or incomplete resection. The tumour can be resected through the classic posterior Shaw-Paulson approach or the newer anterior transcervical approach, introduced by Dartevelle. This method facilitates better exposure of the extreme apex of the lung, brachial plexus and subclavian vessels. Regarding the extent of pulmonary resection, en bloc resection of the involved ribs with a lobectomy is recommended. Recent multimodality studies, involving chemoradiotherapy and surgical resection, show promising results regarding completeness of resection, local recurrence and survival, provided that appropriate staging has been carried out. However, careful patient selection and adequate perioperative management with protection of the bronchial stump or anastomosis are important to achieve reasonable rates of morbidity and mortality. As brain metastases remain one of the most common forms of relapse, further studies are needed to examine the role of prophylactic cranial irradiation in patients with complete resection. Also the addition of other chemotherapy agents or biologic agents such as angiogenesis inhibitors or tyrosine kinase inhibitors gives a new perspective in the treatment of Pancoast tumours.  相似文献   
73.
74.
Summary.  The sodium salts of 2-difluoromethyl-phenyl-α-ketoside of N-acetyl-neuraminic acid (compound 1) and of 4-difluoromethyl-2-methoxy-phenyl-α-ketoside of N-acetylneuraminic acid (compound 2) were designed as potential mechanism-based inhibitors of sialidase. In vitro both of these compounds competitively inhibited the sialidases of Clostridium perfringens and of influenza virus A/HK/1/68. Inhibition was irreversible with the sialidase of Clostridium perfringens whereas it was reversible with that of A/HK/1/68. Compound 2 did not inhibit the hemagglutinin of the virus but exhibited significant anti-influenza activity when added to the medium of Madin-Darby canine kidney (MDCK) cells infected by influenza virus. In non-infected MDCK cells no inhibition of cellular sialidase was observed. Compound 2 did not block primary infection, but inhibited the release of progeny virus from infected cells. Even after 8 passages in its presence, no resistant strains were detected. Because of its high Ki (M) compared to the low Ki (M) of 4 guanidino-Neu 5 Ac 2en and its reversible inhibition of viral sialidase, its development as an anti-influenza agent is no longer envisaged. Nevertheless, as a mechanism-based irreversible inhibitor of the bacterial enzyme, it could at least be useful for investigating the intrinsic role of sialidase in infections caused by this strain. Accepted February 3, 1997; Received November 12, 1996  相似文献   
75.
Summary Glial cell line-derived neurotrophic factor (GDNF) is a potent neurotrophic factor for dopaminergic neurons. Since dopaminergic neurons degenerate in Parkinson's disease, this factor is a potential therapeutical tool that may save dopaminergic neurons during the pathological process. Moreover, a reduced GDNF expression may be involved in the pathophysiology of the disease. In this study, we tested whether altered GDNF production may participate in the mechanism of cell death in this disease. GDNF gene expression was analyzed by in situ hybridization using riboprobes corresponding to a sequence of the exon 2 human GDNF gene. Experiments were performed on tissue sections of the mesencephalon and the striatum from 8 patients with Parkinson's disease and 6 control subjects matched for age at death and for post mortem delay. No labelling was observed in either group of patients. This absence of detectable expression could not be attributed to methodological problems as a positive staining was observed using the same probes for sections of astroglioma biopsies from human adults and for sections of a newborn infant brain obtained at post-mortem. These data suggest that GDNF is probably expressed at a very low level in the adult human brain and its involvement in the pathophysiology of Parkinson's disease remains to be demonstrated. GDNF may represent a powerful new therapeutic agent for Parkinson's disease, however.  相似文献   
76.
The authors report 3 cases of slowly progressive aphasia with different language disturbances: anomia, pure word deafness and Broca's aphasia. All patients were independent in daily life activities. Insight, judgement and overall behaviour were intact. There was no major disturbance of other cognitive functions, but psychometric tests showed mild deficits suggesting widespread involvement. CT scans and magnetic resonance imaging showed focal dilatation of the left sylvian fissure. A positron emission tomographic study showed left perisylvian hypometabolism. A review of the literature yielded an increasing number of cases of this degenerative syndrome affecting dominant hemisphere language areas. Our cases confirm the clinical heterogeneity of degenerative aphasia. Postmortem neuropathological examinations are rare and many causes are found: Pick's disease, Alzheimer's disease or aspecific gliosis.  相似文献   
77.
The topic of this article is to probe into the specificities of suicide by jumping. This means of suicide hasn't been studied much and isn't well known yet.We reviewed the international scientific literature so as to take an in-depth look at this type of auto-aggressive action and highlight the characteristics of the subjects likely to commit suicide by jumping. We thus focus on the available epidemiological data and risk factors associated to suicide jumping. We also describe the prevention strategies most often evoked to deal with this public health issue, which are respectively about improving safety on the identified suicide sites and providing medical and psychological care to individuals likely to commit suicide by jumping.This meta-analysis presents our critical analysis of the methodological limits in the studies exposed. We provide further hints for researching this field of study; they're based on both the taking into account of variables that could be risk factors for this particular means of suicide and the evaluation of the efficiency for the preventive measures used.  相似文献   
78.
79.
Cadiére  G. B.  Himpens  J.  Bruyns  J 《Surgical endoscopy》1996,10(10):957-958
Surgical Endoscopy -  相似文献   
80.
Our work concerned 15 patients (9 males, 6 females) with a mean age of 29.5 years, having a hematologic malignant disease and undergoing allogenic bone marrow transplantation.We studied :
1. The metabolic disorders induced by the conditioning regimen (chemotherapy and total body irradiation) pregraft accompanying cytolysis (day −7, −5, −2).
2. The corrective effect of a total parenteral nutrition introduced 2 days before the transplantation and pursued during 30 days post-graft (day −2 to day 30).
3. The interest of a high calorie intake (BEE × 2) and, after randomisation, of a variable nitrogen intake (24% of the total calorie intake for group A [8 patients] and 14% for group B [7 patients]). The patient characteristics of these two groups were closely comparable. Urinary parameters were studied daily (3-methylhistidine, cratinine, nitrogen) and blood parameters weekly (transferrin, pre-albumin, albumin, retinol binding protein).
We observed globally :
-- An excellent result of the nutritional support without significant weight loss;
-- protein catabolism stopped with a recovery of synthesis of RBP after day 7 and pre-albumin from day 7;
-- a decrease in muscle catabolism.
The randomized study showed :
-- a significant difference in nitrogen excretion between group A and group B;
-- earlier and better protein synthesis recovery in group A, particularly with regard to RBP and pre-albumin.
In conclusion, we recommend for the patients undergoing bone marrow transplantation :
-- nutritional support should be introduced before the conditioning regimen;
-- a high calorie intake (BEE × 2) with a nitrogen intake between 14% and 24% of the total calorie intake;
-- cyclic parenteral nutrition should be pursued during the second and third month post-graft.

Résumé

Nous avons étudié chez 15 malades (9 hommes, 6 femmes) d'âge moyen 29,5 ans, présentant une hémopathie maligne et nécessitant une greffe de moelle osseuse allogénique :
1. Les désordres métaboliques induits par la chimiothérapie et l'irradiation corporelle totale en période de prégreffe au cours de la cytolyse (J −7, J −5, J −2).
2. L'effet correcteur d'une nutrition parentérale introduite deux jours avant la greffe et exclusive durant les 30 jours post-greffe (J −2, J + 30).
3. L'intérêt d'un apport calorique élevé (BEE × 2) et, par randomisation, d'un apport azoté variable (24 % de l'apport calorique total pour le groupe A et 14 % pour le groupe B).
Nous avons étudié quotidiennement certains paramètres urinaires (3MeH, créatinine, azote) et les paramètres sanguins (transferrine, préalbumine, albumine, RBP) l'ont été de façon hebdomadaire.Nous avons constaté globalement un excellent résultat du support nutritif sans perte de poids significative, un arrêt du processus catabolique protéique avec reprise de synthèse après J +7 pour la RBP et pour la préalbumine et une réduction du catabolisme musculaire.L'étude randomisée a mis en évidence :
-- une différence statistique dans l'excrétion axotée, plus intense dans le groupe A,
-- une reprise des synthèses protéiques, plus précoce et plus performante dans ce même groupe pour la RBP et la préalbumine.
En conclusion et compte tenu de l'ensemble des éléments, nous préconisons chez ces malades devant subir une greffe de moelle osseuse allogénique :
-- une attitude préventive en ce qui concerne la nutrition à débuter avant le conditionnement,
-- un apport calorique élevé (BEE × 2) et un apport azoté situé entre 14 % et 24 % de l'apport calorique total,
-- une étude prospective quant à l'intérêt de certains acides aminés et d'une nutrition parentérale cyclique poursuivie au 2e et au 3e mois post-greffe.
Mots clés: greffe de moelle osseuse; nutrition parentérale totale; apport azotéKey-words: bone marrow transplantation; total parenteral nutrition; nitrogen intake  相似文献   
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