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The effects of some antirheumatics on the formation and retraction of collagen lattices seeded with fibroblasts have been studied. Among the antirheumatics, diclofenac was the most active inhibitor of lattice retraction, then tropesin and to a lesser extent indomethacin. Ibuprofen which is known as a very slight inhibitor of protein synthesis was able to significantly enhance lattice retraction when 10 micrograms/ml (48.5 microM) and 50 micrograms/ml (242 microM) were used.  相似文献   
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Renal hemodynamics were studied using an electromagnetic perivascular flow sensor in anesthetized rats injected i.v. with vehicle, 5 or 10 mg/kg body weight (b.w.) sulindac. No hemodynamic changes occurred with vehicle (n=6), but mean arterial pressure was significantly decreased (by 15 mmHg) with sulindac (n=12). In the 5 mg/kg b.w. sulindac group (n=7), renal blood flow progressively and significantly increased from 7.88±0.36 to 8.98±0.58 ml/min, except during concomitant intrarenal infusion of 3 mg/kg b.w. per h proadifen (n=7). The pressure limits for efficient and no renal blood flow autoregulation remained unchanged (approx. 100 and 80 mmHg, respectively). In the 10 mg/kg b.w. sulindac group (n=5), renal blood flow did not change but autoregulatory pressure limits were lowered by 10 mmHg 2 h after treatment (P<0.025). Also, Na+ retention was marked. Prostanoid excretion in urine was significantly reduced with either dose but basal plasma renin activity was not (about 8 ng/ml per h; n=15). When plasma renin activity was enhanced after a reduction in renal perfusion pressure (n=21), it was decreased from 11.5±1.2 to 7.4±0.2 ng/ml per h only by 10 mg/kg b.w. sulindac (P<0.05; n=6). In conclusion, differential effects of sulindac on renal hemodynamics, Na+ excretion and plasma renin activity were demonstrated. Renal hemodynamic changes could be related in part to the cytochrome P-450 arachidonic acid pathway.  相似文献   
5.
The synaptic connections established by grafted noradrenergic (NA) neurons into the lesioned adult rat spinal cord were analysed using immunocytochemistry at the electron microscopic level. An embryonic cell suspension of the locus coeruleus region from E-13 rat embryos was transplanted into the spinal cord following either: (1) spinal cord transection or (2), partial selective denervation by 6-hydroxy dopamine (6-OH DA). One month after grafting, the NA-neurons established, in the two models, an innervation pattern similar to that found in the intact spinal cord. In both models, the transplanted NA-immunoreactive neurons formed extensive synaptic contacts with dendrites, spines and perikarya. The proportion of axodendritic and axospinous contacts was inverse in the two models. The first model thus reproduced more closely the normal synaptic pattern prefering dendritic targets, which could correspond to a better integration of the graft. In the second model, a partially NA-denervated spinal cord, there existed a competition between residual intrinsic and grafted neuron-derived fibres, which presumably affects synaptogenesis. In conclusion, the present study illustrate the complexity of cell interations conducting to the formation of a specific circuitry. Recognition phenomenon are likely modulated by space constraints, which ultimately shape-up the geometry of synaptic contacts.  相似文献   
6.
Between 1980 and 1992, 457 consecutive patients with initial breast cancer entered two successive protocols combining neoadjuvant chemotherapy, hormonotherapy (tamoxifen) and locoregional radiotherapy (teleradiotherapy and boost by iridium) as exclusive locoregional treatment. Cytological diagnosis, hormone receptors, cytological grading were provided by fine needle aspiration. Both protocols included velbe, thiotepa, methotrexate, 5FU and adriamycin with some minor differences regarding the schedule of doses and their number during induction and during the consolidation phase. In both studies, over 50% patients had locally advanced breast cancer (IIb, IIIa or IIIb). Chemotherapy induced tumor regression over 50% in 91% patients of the first protocol (30% complete clinical remission CR) and in 94% patients of the 2nd protocol (40% CR): in this protocol 20 poor responders were given a rescue protocol (2 CR; 9 partial remissions). The 5 year actuarial rate of breast preservation is 94% and the 5 year actuarial rate of local relapses is 15%. The cosmetic results according to Danoff are excellent 20%, good 55%, mean 35%. Disease free survival and overall survival compare favorably to published data: they depend on TNM stages, tumor differentiation and chemotherapy induced early tumor regression.  相似文献   
7.
We previously demonstrated that the alpha 1(I) polypeptide chain of collagen can bind and activate polymorphonuclear neutrophils (PMN). In the present experiments, performed in culture grade 96-well plastic plates coated with collagen, fibronectin, or other proteins, adhesion was assessed by staining the adhering cells after 30 min with crystal violet and measuring absorbance at 560 nm, and activation of PMNs was assessed by measuring the amount of O2-formed. Adhesion occurred at 17 and 37 degrees C but activation at 37 degrees C only. Monoclonal antibody anti-CD 18 inhibited adhesion, showing that the receptor of collagen I on PMNs is a beta 2 integrin. On the other hand, adhesion of PMNs to fibronectin was inhibited by monoclonal antibodies to CD18 and to CD11b.  相似文献   
8.
Phonological representations in children with SLI: a study of French.   总被引:1,自引:0,他引:1  
The present research examined the quality of the phonological representations of French children with specific language impairment (SLI) and those with normal language development (NLD). Twenty-five children with SLI and 50 children with NLD matched on lexical age level participated in an auditory lexical decision task. The observations gathered in our study can be summarized as follows. First, children with a higher receptive lexical level performed better, and this was true both for children with NLD and children with SLI. Second, both children with NLD and those with SLI were more likely to reject pseudowords resulting from a modification affecting the number of syllables of a word than pseudowords resulting from a slight modification with the number of syllables unchanged. This difference, however, was greater for the children with SLI, who appeared to have much difficulty rejecting pseudowords resulting from slight modifications. Finally, the performance of children with SLI was particularly poor when presented with pseudowords resulting from a slight modification at the beginning or the end of a word. These findings are interpreted as supporting the hypothesis of an under-specification of phonological representations in children with SLI.  相似文献   
9.
Intracranial hemorrhage is an uncommon complication of antithrombotic therapy. We present two patients who suffered life-threatening intracranial bleeding as a complication of thrombolytic/anticoagulant treatment. Early diagnosis and treatment appear to be crucial factors for survival. We suggest an approach to perioperative management for intracranial hemorrhage resulting from antithrombotic therapy.  相似文献   
10.
Molecular epidemiological studies of hepatitis C virus (HCV) in the Caribbean may help to specify the origin and spread of HCV infection. Indeed, the Caribbean population is intermixed from European and African origins and geographically close to the American continent. We characterized HCV genotypes in the Caribbean island of Martinique. HCV genotypes were analyzed by sequencing or reverse hybridization in the 5' noncoding region (5'NC) in 250 HCV-monoinfected and 85 HCV-human immunodeficiency virus (HIV)-coinfected patients. In addition, sequencing in the nonstructural 5B (NS5B) gene was required to determine the subtype or to perform phylogenetic analysis in selected samples. Genotypes 1 to 6 were found, respectively, in 84.4, 6.8, 5.2, 2.8, 0.4, and 0.4% of 250 HCV-monoinfected patients and in 71.7, 7.1, 15.3, 5.9, 0, and 0% of 85 HCV-HIV-coinfected patients. HCV-1b was found in 66.4% of the HCV-monoinfected patients and was associated with blood transfusion, whereas HCV-1a was detected in 41.2% of the HCV-HIV-coinfected patients and was associated with intravenous drug use (IVDU). The HCV-3 strains belonged to subtype 3a and were linked to IVDU. Phylogenetic analyses were focused on HCV-2 and HCV-4, which are common in Africa. Two opposite patterns were evidenced. NS5B sequences from 19 HCV-2 isolates were affiliated with many different subtypes described either in Europe or in West Africa, suggesting an ancient radiation. In contrast, seven of the nine HCV-4 NS5B sequences ranged within HCV-4a and HCV-4d clusters spreading in continental France by the IVDU route. Epidemiological data demonstrate the recent introduction of HCV-4a and -4d subtypes into the Caribbean.  相似文献   
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