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1.
Both systemic and intracerebral administrations of the cholinergic muscarinic antagonist, scopolamine, have been shown to inhibit naturally occurring sexual behavior in intact, cycling female rats. The present study examined the facilitative effects of the acetylcholinesterase inhibitor, physostigmine (eserine), on sexual behavior in intact, cycling female rats. Cycling was determined by daily monitoring of sexual behavior and vaginal cytology. When administered during either early proestrus or proestrus, physostigmine activated lordosis 15 min and 1 hr after intraventricular infusion (10 micrograms bilaterally). However, infusion of physostigmine failed to facilitate lordosis 15 min after administration during either diestrus I, mid-diestrus, or diestrus II. The administration of this cholinergic agent did not interrupt cyclicity patterns. Because estrogen levels are highest during proestrus and cholinergic facilitation appears to be limited to this time, it is suggested that estrogen priming of central cholinergic systems is necessary for the cholinergic regulation of sexual behavior in intact, cycling female rats.  相似文献   
2.
An analog, 6-(2'-hydroxyethylidene)-4 beta-methyl-1-azabicyclo[3.2.0]hept-2-ene-2- carboxylate (11), of the carbapenem beta-lactamase inhibitor, asparenomycin A, was synthesized. It possessed a spectrum of antibacterial activity that was comparable to that of asparenomycin A but was less effective as a beta-lactamase inhibitor. With ampicillin, it only exhibited a moderate level of synergy against a variety of beta-lactamase-producing organisms. Although the presence of a 4 beta-methyl group in the analog brought about a significant increase in chemical stability relative to that of asparenomycin A, it did not result in an increase in stability to kidney dehydropeptidase enzyme.  相似文献   
3.
The superior orbital syndrome has been reported as a very rare complication of orbital fracture. In emergency clinical examination and computed tomography of the cranio-orbital region have provided diagnosis of the compression of the superior orbital fissure content by oedema and/or hematoma. These examinations have determined the type of cranio-orbital fractures and the absence of extra-dural haemorrhage, optical nerve damage or compression, which required emergency treatment. After surgical treatment of the cranio-orbital fracture by temporal and transconjunctival approach, the orbital fissure syndrome has required supervision. The recovery of ophthalmoplegia has taken several months. Minor after effects have been observed for the patient reported.  相似文献   
4.
5.
Summary In view of the variety of 3D representation techniques, a clinical study was carried out in order to evaluate their respective usefulness. It appears that a single technique cannot be claimed to be valid for all clinical situations and that a combination of representations brings more relevant information. Among the different techniques a clear delineation must be established between those which allow the accurate definition of landmarks (multiplanar reformation, surface representation), and those which do not (integral shading, reconstructed radiology). The main point is the possibility to recognize anatomical landmarks on these latter modes and to choose oblique cut planes in relation to them. Visualization quality is strongly dependent upon the acquisition protocol which must provide a spatial resolution as isotropic as possible.
Une revue de différents modes de visualisation en haute résolution d'un objet volumique avec des applications
Résumé Face à la variété des techniques de représentation 3D une étude clinique a été conduite pour évaluer leurs utilités respectives. Il apparait qu'une technique unique ne peut pas convenir à toutes les situations cliniques et qu'une combinaison de différents modes de présentation apporte une information plus pertinente. Parmi les différentes techniques une distinction claire doit être établie entre celles qui autorisent la prise de repères précis (reformatage multiplanaire, représentation de surface), et celles qui ne le permettent pas (ombrage intégral, radiologie reconstruite). Le point principal est la possibilité de reconnaître des repères anatomiques sur ces derniers modes et de choisir des plans de coupe en relation avec eux. La qualité de la visualisation dépend étroitement du protocole d'acquisition qui doit fournir une résolution aussi isotrope que possible.
  相似文献   
6.
Endothelial leukocyte adhesion molecule-1 (ELAM-1) has been determined to be the mediator of adhesion of colon carcinoma cells to interleukin-1 (IL-1)-activated endothelial cells. To identify ELAM-1 ligand in colon carcinoma cells, we have screened a series of 11 monoclonal antibodies directed to these cells and found that only one MBr8 was able to inhibit the IL-1-induced increment in adhesion of HT29 and of SW948 colon carcinoma lines to endothelial cells. In contrast, MBr8 did not bind to polymorphonuclear cells, monocytes, and lymphocytes and did not inhibit polymorphonuclear adhesion to IL-1-activated endothelial cells. As expected, an ELAM-1 monoclonal antibody strongly inhibited IL-1 induced increment of adhesion of HT29, SW948, and polymorphonuclear cells. As negative control, MG63 osteosarcoma cells were used. These cells adhere more efficiently to IL-1 activated endothelial cells but MBr8 and ELAM-1 monoclonal antibodies did not affect their adhesion. The effect of MBr8 was also tested in an experimental system in vivo. As described previously, radiolabeled HT29 cell retention in the lung of nude mice was increased in animals given IL-1. MBr8 administration to nude mice or pretreatment of tumor cells with it inhibited this effect. These data suggest that cell adhesion to ELAM-1 might be mediated by different, cell type specific, sugar ligands.  相似文献   
7.
The pharmacokinetics of recombinant human relaxin (rhRlx) after intravenous (iv) bolus administration and the absorption of rhRlx after intracervical or intravaginal administration were determined in nonpregnant women. The study was conducted in two parts. In part I, 25 women received 0.01 mg/kg rhRlx iv. After a minimum 7-day washout period, these women were dosed intracervically (n = 10) or intravaginally (n = 15) with 0.75 or 1.5 mg rhRlx, respectively, in 3% methylcellulose gel. Part II was a double-blind, randomized, three-way crossover study in 26 women. At 1-month intervals, each woman received one of three intravaginal treatments consisting of 0 (placebo), 1, or 6 mg rhRlx in 3% methylcellulose gel. The serum concentrations of relaxin following iv administration were described as the sum of three exponentials. The mean (±SD) initial, intermediate, and terminal half-lives were 0.09 ± 0.04, 0.72 ± 0.11, and 4.6 ± 1.2 hr, respectively. Most of the area under the curve was associated with the intermediate half-life. The weight-normalized clearance was 170 ± 50 mL/hr/kg. The observed peak concentration was 98 ± 29 ng/mL, and the weight-normalized initial volume of distribution was 78 ± 40 mL/kg, which is approximately equivalent to the serum volume. If central compartment elimination was assumed, the volume of distribution at steady state (V ss/W) was 280 ± 100 mL/kg, which is approximately equivalent to extracellular fluid volume. V ss/W could be as large as 1300 ± 400 mL/kg without this assumption. After intravaginal administration of the placebo gel, endogenous relaxin concentrations were evident (i.e., 20 pg/mL) in 9 of the 26 women (maximum concentrations, 23–234 pg/mL). A similar proportion of women (approximately 35–40%) exhibited measurable serum concentrations of relaxin following intravaginal rhRlx treatment; this proportion increased to 90% following intracervical rhRlx treatment. For both routes of administration, the maximum serum concentrations of relaxin were usually within the range of values observed for endogenous relaxin, suggesting that the absorption of rhRlx was minimal.  相似文献   
8.
Idiopathic subglottic stenosis is a rare condition. The records of five patients with idiopathic subglottic stenosis treated between 1989 and 1998 were reviewed. All were female and had similar clinical and histopathologic features. Endoscopic dilatation or/and radial CO2 laser and dilatation were successful in maintaining the airway of all five patients without tracheotomy. The pathogenesis of idiopathic subglottic stenosis is strictly speculative, for this reason we advocate a conservative approach.  相似文献   
9.
The effect of intra-cerebrally infused compounds in animal models of anxiety were reviewed. A large body of evidence suggested that benzodiazepine agonists in different brain regions--including areas of the raphe, hypothalamus, periaqueductal gray, septum, hippocampus, and amygdala--produce reasonably consistent anxiolytic effects in a variety of animal models. However, evidence regarding the effects on anxiety of 5-HT1A agonists, 5-HT2 compounds, and 5-HT3 antagonists was somewhat less extensive, both anatomically and behaviourally, and more complex. For example, establishing receptor specificity for 5-HT ligand effects was often complicated by the lack of 'silent' and/or selective antagonists. Neuropeptides had significant effects on anxiety, but these were shown in a smaller number of animal models and in a limited number of brain regions. Regardless of the compounds tested, however, there seemed to be a surprising number of double dissociations (brain site by behavioural test). In fact in some instances, different fear reactions appeared to be controlled by distinct receptor subpopulations within particular parts of the limbic system. These results suggest that the neural control of anxiety might be analogous in organization to sensorimotor systems, i.e., anxiety is controlled by complex systems of multiple, distributed, parallel pathways.  相似文献   
10.
Marjolin's ulcer. The LSU experience   总被引:1,自引:0,他引:1  
L H Barr  J W Menard 《Cancer》1983,52(1):173-175
Skin cancers originating in areas of chronic injury (Marjolin's ulcers) are thought to behave in a more aggressive fashion than those due to other causes. The initial surgical treatment, especially the management of the regional lymph nodes, remains controversial. This review of 37 patients with Marjolin's ulcer evaluated the effectiveness of local surgical treatment at our center. Three of 18 patients treated with amputation developed recurrences and died of metastatic disease. Five of 16 patients treated by wide excision developed recurrences, two dying with metastatic disease, the remaining three apparently cured by additional surgery. Only six (17.6%) of the patients treated by "local" modalities, i.e., wide excision or amputation, developed subsequent regional node metastases. Recurrences following local excision tend to be local and can usually be managed by re-excision or amputation. It can be inferred from this study that prophylactic node dissections are not required in most patients with Marjolin's ulcers.  相似文献   
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