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71.
We have studied the effect of Ambroxol on the production of Interleukin-1 (IL-1) and Tumor Necrosis Factor (TNF) in human mononuclear cells (MNC). For this purpose MNC were cultured for 24 h in the presence of endotoxin and different doses of Ambroxol. The results indicate that Ambroxol markedly inhibited IL-1 and TNF production at doses of 10–100 g/ml, without any apparent toxicity.  相似文献   
72.
73.
  1. 8-epi-prostaglandin (PG) F, a major F2 isoprostane, is produced in vivo by free radical-dependent peroxidation of lipid-esterified arachidonic acid. Both cyclo-oxygenase isoforms (COX-1 and COX-2) may also form free 8-epi-PGF as a minor product. It has been recently seen in human volunteers that the overall basal formation of 8-epi-PGF in vivo is mostly COX-independent and urinary 8-epi-PGF is therefore an accurate marker of ‘basal'' oxidative stress in vivo.
  2. To test the validity of this marker in the rat, we evaluated in vivo the effect of COX inhibition on the formation of 8-epi-PGF vs prostanoids. Two structurally unrelated COX inhibitors (naproxen: 30 mg kg−1 day−1; indomethacin: 4 mg kg−1 day−1) were given i.p. to rats kept in metabolic cages. In vivo formation of 8-epi-PGF was assessed by measuring its urinary excretion. Prostanoid biosynthesis was assessed by measuring urinary excretion of major metabolites of thromboxane (TX) and prostacyclin (2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF). All compounds were selectively measured by immunopurification/gas chromatography-mass spectrometry.
  3. Naproxen reduced urinary excretion of 2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF but, unexpectedly, also that of 8-epi-PGF (82, 49 and 52% inhibition, respectively). Indomethacin had a similar effect (77, 69 and 55% inhibition). Esterified 8-epi-PGF in liver and plasma remained unchanged after indomethacin.
  4. These findings prompted us to re-assess the contribution of COX activity to the systemic production of 8-epi-PGF in man. We gave naproxen (1 g day−1) to healthy subjects (four nonsmokers and four smokers). Urinary 8-epi-PGF remained unchanged in the two groups (9.63±0.99 before vs 10.24±1.01 after and 20.14±3.00 vs 19.03±2.45 ng h−1 1.73 m−2), whereas there was a marked reduction of major urinary metabolites of thromboxane and prostacyclin (about 90% for both 11-dehydro-TXB2 and 2,3-dinor-TXB2; >50% for 2,3-dinor-6-keto-PGF).
  5. To investigate whether rat COX-1 produces 8-epi-PGF more efficiently than human COX-1, we measured the ex vivo formation of 8-epi-PGF and TXB2 simultaneously in whole clotting blood. Serum levels of 8-epi-PGF and TXB2 were similar in rats and man.
  6. We conclude that a significant amount of COX-dependent 8-epi-PGF is present in rat but not in human urine under normal conditions. This implies that urinary 8-epi-PGF cannot be used as an index of near-basal oxidant stress in rats. On the other hand, our data further confirm the validity of this marker in man.
  相似文献   
74.
The influence exerted by monoamines on acetylcholine release was studied in electrically stimulated slices of guinea pig nucleus basalis magnocellularis (nbM) prelabelled with 3H-choline (3H-Ch).Noradrenaline, 30 M, and clonidine, 1 M, reduced the evoked 3H-Ch efflux by about 50%, but phenylephrine, 100 M. did not; idazoxan, 0.1 M. but not prazosin, 1 M, antagonized these effects. pointing to the involvement of alpha2 receptors. Apomorphine, 1 or 30 M. reduced 3H-Ch efflux from nbM slices as well. The effect was shared by quinpirole, 1 or 10 M, but not by 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benz-azepine (SKF 38393). 10 M, and was antagonized by sulpiride, 1 M, but not by R-(+)-8-chloro-2,3,4,5-tetra-hydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol (SCH 23390). 1 M, suggesting the involvement of the D2 receptor subtype.5-hydroxytryptamine (5-HT) 0.3–30 M, and alphamethyl-5-HT, 10 M, significantly increased 3H-Ch efflux from nbM slices; the 5-HT2 antagonist ritanserin, 1 M. prevented this response. 2-methyl-5-HT, 1–30 M, inhibited the evoked 3H-Ch efflux and its effect was prevented by the 5-HT3 antagonist 1H,3,5H-tropan-3-yl-3,5-dichlorobenzoate (MDL 72222). 1 M.These findings indicate that i) catecholamines inhibit nbM neurons through alpha2 and D2 receptors and that ii) a complex serotonergic modulation of cholinergic function exists in the nbM, involving the activation of various receptor subtypes. which can mediate opposite responses. Correspondence to: A. Siniscalchi at the above address  相似文献   
75.
Duane's retraction syndrome is sometimes associated with developmental ocular and extraocular abnormalities. This disorder may also be present in association with specific malformative syndromes. The authors report the clinical features of a seven-year-old female affected by Duane's retraction syndrome (D.R.S.), rectoperineal fistula, imperforate anus and other congenital malformations. From two extensive reviews of 106 reports published before 1982 and from a search (using Medline 1981-1994) for reports of congenital malformations associated with this syndrome, no cases of sporadic D.R.S. associated with the perineal malformations mentioned were found, even though imperforate anus is considered the commoner of hindgut malformation.  相似文献   
76.
The general consensus among States which have had their section 1115 demonstration projects approved is that there is no one best way to implement State health care reform. The Health Care Financing Administration (HCFA), however, wished to discern how States were accomplishing the task of implementing the demonstrations, and solicited responses from State representatives whose section 1115 demonstration waivers had been approved. The resulting article gives an overview of this implementation process from four State perspectives. Written by representatives from Oregon, Hawaii, Tennessee, and Rhode Island, the ideas presented here are indicative of the complex undertaking of State health care reform.  相似文献   
77.
OBJECTIVES: To categorize the radiological presentation of osteosarcoma of the jaws. METHODS: Conventional radiographs and CT scans of nine patients with histologically proven osteosarcoma were reviewed. RESULTS: Five patients were men and four women, aged between 20 and 51; four lesions were in the maxilla and five in the mandible. Three radiological presentations of osteosarcoma of the jaw were identified. The first was radiolucent, characterized by a total absence of bone formation within the tumour. The second had a mottled appearance with small areas of amorphous ossification separated by non-ossified tumour tissue. The third, with lamellar ossification, was typically characterized by bony plates irradiating from a focus like a 'sunburst'. CONCLUSION: Radiological diagnosis of osteosarcoma of the jaw can be difficult because of its variable appearance. CT is particularly useful.  相似文献   
78.
High-frequency ultrasound (US) is an efficient, rapid and inexpensive altenative to magnetic resonance imaging (MRI) for investigation of diseases in the soft tissues of the wrist and hand. US allows detection of foreign bodies and the reliable identification of a variety of traumatic lesions affecting tendons, annular pulleys, ligaments, vessels and nerves. Inflammatory diseases of tendons, including acute and chronic tenosynovitis and some degenerative conditions in the wrist and hand, can also be diagnosed. In entrapment neuropathies, US is able to identify nerve shape changes and possible extrinsic space-occupying lesions that may cause nerve compression within the tunnels. In patients with localized swelling of the hand or wrist, US is able to assess the presence of an expansile lesion and to characterize its nature in most cases. The objective of this article is to review the main findings and the primary indications of US in the investigation of disorders of the hand and wrist. Received: 10 September 1998 Accepted: 24 November 1998  相似文献   
79.
Summary. Defects in mitochondrial enzymes have been found not only in substantia nigra, but also in platelets from Parkinson's Disease (PD) patients, suggesting a systemic impairment of energy metabolism. Since platelets present an energy-dependent glutamate uptake similar to that described in central nervous system, glutamate uptake was determined in platelets from 34 PD patients and 21 age-related normal controls, as Na+-dependent [3H]glutamate influx; glutamate level was also analyzed by reverse-phase HPLC. A 50% reduction of glutamate uptake (p < 0.001) was observed in idiopathic PD patients, respect to controls and secondary parkinsonian syndromes. The decrease correlated with the severity of PD, measured by the UPDRS (r = −0.54; P < 0.05). Glutamate level was increased in platelets of PD patients, but was not correlated to the uptake decrease. Both phoenomena may be explained by the modifications of mitochondrial enzymes described in platelets, which could be used as a peripheral model of glutamatergic function in PD. Received October 7, 1998; accepted January 7, 1999  相似文献   
80.
BACKGROUND: At present video thoracoscopy is a primary diagnostic procedure in the diagnosis of pleural diseases, particularly when pleural effusions have unknown origin. METHODS: In this article the personal experience is reported about 20 patients in which video thoracoscopy was very important in the diagnosis of pleural effusions. RESULTS: Thoracoscopy permits to explore the thoracic cavity and to do a lot of biopsies. Video thoracoscopy, made it possible to diagnose 10 cases of malignant mesothelioma, 2 cases of pleural metastases (renal mts and mammary mts) and 8 cases of inflammatory diseases. CONCLUSIONS: At last, is laid on the contribution of video thoracoscopy to determine the stage of malignant mesothelioma.  相似文献   
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