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1.
Most of the techniques described in the literature for the repair of chronic partial ACL tears, don’t spare the intact portion of the ligament. The aim of this study was to perform a prospective analysis of the results of augmentation surgery using gracilis and semitendinosus tendons to treat partial sub-acute lesions of the ACL. This technique involves an “over the top” femoral passage, which enables salvage and strengthening of the intact portion of the ACL. The study included 47 patients treated consecutively at our institute from 1993 to 1998, with a mean injury-surgery interval of 18 weeks (range 12–36). The patients were followed up by clinical and instrumental assessment criteria at 3 months, 1 and 5 years after surgery. Clinical assessment was performed using the IKDC form. Subjective and functional parameters were assessed by the Tegner activity scale. Instrumental evaluation was done using the KT-2000 instrument: the 30-pound passive test and the manual maximum displacement test were performed. We obtained good or excellent results in 95.7% of cases. No recurrences in ligamentous laxity were observed. We believe that the described technique has the advantage of being compatible with ACL anatomy, and enables very rapid functional recovery.  相似文献   
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The chain propagation rate constants for the polymerization of ethylene and propene in the presence of δ-TiCl3/Al(CH3)3 at 22 °C are determined by means of a 13C NMR analysis of suitable block copolymers. The numerical values of the rate constants are compared with those previously reported.  相似文献   
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The bias favoring deletion over inversion in DH-JH rearrangement has been known for years, but the underlying mechanism has yet to be fully defined. It has been suggested that the ratio of deletion/inversion is determined by the combined effect of two factors: (i) the relative strengths of 5' and 3' recombination signal sequences (RSS) of a DH segment, and (ii) the efficiency with which the deletional product (one joint) forms relative to the inversional product (two joints). In this study, we analyzed for the first time the effect of factor 1 alone on the biased 3' RSS utilization in DH-JH joining by using deletional plasmids in an extrachromosomal substrate V(D)J recombination assay. It was found that the 3' RSS and associated coding end (12 bp) mediate recombination more efficiently than the 5' RSS/coding end DH-JH plasmids. These results demonstrate that the effect of the RSS/coding end alone can account, at least partially, for the predominant deletion in DH-JH recombination. The potential effect of the relative strength of RSS and associated coding end on the ordered rearrangement of DH-JH followed by VH to DH-JH was also assessed. When recombination frequencies of D-->J (3' DH to J3) were compared with frequencies of V-- >D (VHPJ14 to 3' DH or VHOX2 to 3' DH), it was found that V-->D joining was, if anything, more efficient than D-->J joining. Therefore, if all three segments were accessible, RSS/coding end effects would not contribute to the ordered rearrangement of the IgH locus.   相似文献   
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Summary Varus deformity of the knee is common in young children who have suffered from fulminating purpura. This study was directed at the anatomic features of the vascularisation of the upper end of the tibia that might account for such deformation. It was based on the dissection of 28 anatomic specimens prepared by injection of Indian ink into the vascular trunk. 16 specimens were diaphanised for better analysis of the intracartilaginous distribution of the vessels. The study showed that the vascularisation of the medial condyle of the tibia is poor and of terminal nature, which may explain the occurrence of ischemic growth disorders following fulminating purpura.
Etude de la vascularisation artérielle du condyle médial du tibia chez le foetus
Résumé Les déformations en varus du genou chez les jeunes enfants ayant présenté un purpura fulminans sont fréquentes. Ce travail a pour objet de rechercher les caractéristiques anatomiques de la vascularisation de l'extrémité supérieure du tibia qui peuvent expliquer ces déformations. L'étude porte sur la dissection de 28 pièces anatomiques préparées par injection de l'axe vasculaire à l'encre de Chine. Pour mieux analyser la répartition intra-cartilagineuse des vaisseaux, 16 pièces ont été diaphanisées. Cette étude montre que la vascularisation du condyle médial du tibia est pauvre, de type terminal, ce qui peut expliquer la survenue de troubles de croissance ischémiques dans les suites d'un purpura fulminans.
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7.
BACKGROUND: The counting of intraepithelial lymphocytes (IELs) in the villous tips of architecturally normal small bowel biopsy specimens was proposed as a method to measure mucosal infiltration in gluten sensitive patients. AIMS: To apply this straightforward method in duodenal biopsy specimens from patients affected by potential coeliac disease (PCD) to verify whether it can discriminate these patients from controls. METHODS: Paraffin wax embedded duodenal sections from 11 patients affected by PCD were stained with an antihuman CD3 antibody. Sections from 19 patients affected by treated coeliac disease (TCD) and 17 patients in whom coeliac disease was excluded were stained with the same antibody to serve as controls. The slides were examined blindly. IELs/20 enterocytes in five randomly chosen villous tips were counted. Patients affected by PCD were all on a gluten containing diet. They had an architecturally normal duodenal mucosa and were positive for endomysial antibody. Both TCD and non-coeliac controls were negative for endomysial antibody. RESULTS: The mean villous tip IEL scores were 4.6 (SD, 1.5; range, 1.4-7.8) in non-coeliac controls, 7.9 (SD, 4.0; range, 2.0-18.6) in TCD, and 9.2 (SD, 4.7; range, 5.8-21.8) in patients with PCD. The difference between PCD and non-coeliac controls was significant. CONCLUSIONS: This is a very simple and sufficiently reliable method to count IELs. In patients with an architecturally normal duodenal mucosa, the IEL count in villous tips helps to distinguish between patients with PCD and non-coeliac controls.  相似文献   
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This paper reports the predominantly syndiotactic‐specific polymerization of propylene in the presence of titanium monoamidinate/methylaluminoxane (MAO) catalysts. The same catalysts, depending on the reaction conditions, also promote either predominantly 1,4‐cis or 1,4‐trans polymerization of 1,3‐butadiene and polymerization of styrene either to highly syndiotactic or to stereoirregular polymer. Some preliminary information about the features of propylene polyinsertion is also reported.

Expansion of the 20–24 ppm region of the 13C NMR spectrum of sample 2. The starred resonance at 21.75 ppm and the shoulders are not assigned.  相似文献   

9.
Polygonum multiflorum stilbeneglycoside (PMS) is a water-soluble fraction of Polygonum multiflorum Thunb. , one of the most famous tonic traditional Chinese medicines, that has protective effects on the cardiovascular system. The purpose of the present study is to elucidate the effects of PMS on macrophage-derived foam cell functions and the reduction of severity of atherosclerosis in hypercholesterolemic New Zealand White (NZW) rabbits. NZW rabbits were fed for 12 weeks with a normal diet, a high cholesterol diet, or a high cholesterol diet associated with irrigation with different doses of PMS (25, 50, or 100 mg/kg). Treatment of NZW rabbits fed with high cholesterol diet with 100 mg/kg PMS attenuated the increase in plasma cholesterol, low-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, and plasma triglyceride. Treatment with 50 and 100 mg/kg PMS caused 43% and 60% decrease in atherosclerotic lesioned area ratio to total surface area, respectively. In U937 foam cells, PMS could decrease the high expression of intercellular adhesion molecule (ICAM)-1 protein and the vascular endothelial growth factor (VEGF) protein levels in the medium induced by oxidized lipoprotein when analyzed by flow cytometry. The results proved that PMS is a powerful agent against atherosclerosis and that PMS action could possibly be through the inhibition of the expression of ICAM-1 and VEGF in foam cells.  相似文献   
10.
BACKGROUND: Our aim was to compare the clinical efficacy of the Tannenbaum (TB) biliary prostheses, a recently designed Teflon stent without side holes, with the Cotton-Huibregtse (CH) polyethylene stent. METHODS: Fifty-seven patients (26 men, mean age 75.5 years) with unresectable malignant tumors and distal biliary stenosis were included (38 pancreatic head cancer, 17 cholangiocarcinoma, 2 ampullary cancer). Patients were prospectively randomized to have a 10F, 7 cm long TB (29 patients) or CH (28 patients) stent inserted endoscopically. Four patients (2 TB and 2 CH) were excluded: 3 because of the failure of stent insertion and 1 because of a protocol violation. The patients were evaluated clinically and, if necessary, with biochemical tests every month until death or until they needed surgery for symptoms of gastric outlet obstruction. When occlusion or dislocation occurred, the stent was replaced with one of the same type. Cumulative stent patency and patient survival were estimated with the Kaplan-Meier life-table analysis and compared by log-rank chi-square test. RESULTS: The two groups were comparable in mean age, gender, and diagnosis. The patients were followed for a mean of 145.5 days (range 24 to 613); by the end of the study 47 patients (81%) had died or developed symptoms of gastric outlet obstruction. Median survival was 88 days (range 24 to 613) in the TB group and 75.6 days (23 to 486) in the CH group. Stent exchange (occlusion 16, dislocation 3) was necessary for 5 patients in the TB group and 7 in the CH group. No statistical difference was found on comparing the mean duration of function of the first, second, and third stents (analysis of variance, p = 0.80). The median duration of stent function was 96 days (range 11 to 613) in the TB group and 75.5 days (range 23 to 323) in the CH group. No significant difference was found in either survival time (p = 0.48) or stent patency (p = 0.12). CONCLUSION: This study found no significant advantage of the Tannenbaum prostheses over the standard polyethylene stent in the palliation for patients with distal malignant biliary stenosis with regard to survival or length of stent patency.  相似文献   
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