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91.
To study the possible influence of colonic diverticula on the risk of peritonitis of enteral (intestinal) origin in patients undergoing continuous peritoneal dialysis, a barium enema was carried out as a pretreatment investigation in 129 consecutive patients starting CAPD over a 9-year period. In this prospective study comprising 3103 patient months, a total of 44 (15% of all) episodes of peritonitis with micro-organisms of enteral origin occurred in 30 of the 129 patients. The estimated probability of developing such an episode was 16% and 24%, respectively, within 1 or 2 years of treatment. Diverticula (greater than or equal to 1) were found in 54 (42%) of all patients. In all cases the following factors: greater than or equal to 10 diverticula, diverticular size of greater than or equal to 10 mm and diverticula in the ascending, transverse, or descending colon, significantly increased the risk of developing peritonitis of enteral origin (P less than 0.05). Neither diverticula in the sigmoid colon nor diverticulitis, as assessed by radiological findings, were identified as risk factors. Enteral episodes (as defined in this study) appear to represent mainly microperformations of existing diverticula; such episodes should probably be regarded as and handled differently from episodes due to major perforations of the colon secondary to diverticulitis. We conclude that diverticular disease of the non-sigmoid colon is a risk factor for peritonitis in CAPD.  相似文献   
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S A Cohen  W E Müller 《Brain research》1992,584(1-2):174-180
The effect of aging on the properties of N-methyl-D-aspartate (NMDA) receptors in the forebrain of female NMRI mice was investigated using the antagonist [3H]MK-801 as radioligand. Compared to young (3 months) mice, aged (20 months) mice showed changes of the properties of the NMDA receptor at three different levels: (1) the density was reduced by about 35%; (2) the efficacy of L-glutamate and glycine for stimulating specific [3H]MK-801 binding was enhanced, probably because more NMDA receptor-associated ion channels are closed under baseline conditions in the aged brain; (3) the affinity of L-glutamate and glycine to its binding sites at the NMDA receptor complex was also enhanced. Chronic treatment of aged mice with phosphatidylserine (20 mg/kg, i.p., once daily) for three weeks completely normalized enhanced efficacy and affinity of L-glutamate and glycine and elevated NMDA receptor density by approximately 25%. These findings are consistent with the assumptions that deficits of the NMDA receptor are one of the mechanisms of age-related cognitive impairment and that the beneficial effects of phosphatidylserine treatment on cognitive deficits of aged individuals might be partially due to the effects of this drug on age-related NMDA receptor deficits.  相似文献   
95.
The value of MR imaging was compared with that of high-resolution CT in assessing chronic infiltrative lung disease in 25 patients. The cases included nine patients with usual interstitial pneumonia, six with sarcoidosis, four with hypersensitivity pneumonitis, and six with miscellaneous conditions. The diagnosis was proved by biopsy (n = 17) or by means of clinical, laboratory, and radiologic criteria (n = 8). All patients had 1.5-T MR imaging and CT of the chest. Cardiac-gated T1-, proton density-, and T2-weighted spin-echo sequences were obtained. Initially, the MR images were assessed independently; later they were compared directly with the corresponding CT scans. In six patients, MR images and CT scans were obtained before open lung biopsy, and the images and scans were assessed prospectively. CT was superior to MR imaging in the anatomic assessment of the lung parenchyma and in showing fibrosis. However, areas of air-space opacification (ground-glass opacities) were seen as well on MR as on high-resolution CT. In the six patients who had open lung biopsy, areas of air-space opacification seen on MR and on CT corresponded to areas of active alveolitis or air-space infiltrates pathologically. Follow-up in six patients showed equal degrees of change in the air-space opacification over time on MR and CT. We conclude that, although MR imaging is inferior to high-resolution CT in the assessment of chronic infiltrative lung diseases, it may play a role in the assessment and follow-up of patients with air-space opacification.  相似文献   
96.
The physiological phenomenon of changes in callus formation during distraction was first described by Codivilla at the beginning of this century. Having investigated and proved the influence of tension stress on callus formation, Ilizarov used this as a method to treat limb shortening and deformities. Because of his remarkable results we introduced this method in our hospital in 1990, using the original Ilizarov ring fixator. From November 1990 to December 1991, we used this technique in 10 cases of combined post-traumatic bone shortening with deformity (the tibia was affected in six patients, the femur in three and the forearm in one). The mean shortening was 3.1 cm, the mean varus or valgus deformity 9.5 degrees, the mean anteflexion or recurvation 8.3 degrees, and the mean rotation deformity 8.5 degrees. Distraction/correction lasted between 8 and 55 days (mean: 37 days). Fixation was necessary for between 60 and 339 days. If corticotomy was performed in the diaphyseal bone, fixation lasted almost twice as long (11.33 days/mm lengthening) as in the metaphyseal area (6.55 days/mm lengthening). There were 14 complications, most of which were considered minor. The latter included pin infections (4), wire breaking (1) and restricted range of motion of the knee or ankle (5). Among the major complications were two nerve irritations, which recovered spontaneously, and two pin-induced local bone infections, which required surgical intervention. Achievement of the goals of treatment-complete correction of shortening and deformity-was not affected by these complications.  相似文献   
97.
We have produced a range of monoclonal antibodies which stain human intrahepatic bile ducts of different sizes. Amongst 26 monoclonal antibodies produced, five clones reacted specifically with bile ducts of different sizes, of which three have been maintained in culture and their viability following freezing and thawing confirmed. Staining patterns varied between normal adult liver tissue, normal fetal liver tissue and a variety of hepatobiliary diseases. The antibodies provide further evidence of the immunological heterogeneity of the human intrahepatic biliary tree and support the hypothesis that proliferating bile ductules are derived from periseptal hepatocytes. The preparation of the antibodies, their staining reactions in normal adult, normal fetal and a variety of liver diseases are described.  相似文献   
98.
Many breast tumors appear to follow a predictable clinical pattern, being initially responsive to endocrine therapy and to cytotoxic chemotherapy but ultimately exhibiting a phenotype resistant to both modalities. Using the MCF-7 human breast cancer cell line as an example of an 'early' phenotype (estrogen and progesterone receptor positive, steroid responsive, low metastatic potential), we have isolated and characterized a series of hormone-independent but hormone-responsive variants (MIII and MCF7/LCC1). However, these variants remain responsive to both antiestrogens and cytotoxic drugs (methotrexate and colchicine). MIII and MCF7/LCC1 cells appear to mimic some of the critical aspects of the early progression to a more aggressive phenotype. An examination of the phenotype of these cells suggests that some hormone-independent breast cancer cells are derived from hormone-dependent parental cells. The development of a hormone-independent phenotype can arise independently of acquisition of a cytotoxic drug resistant phenotype.  相似文献   
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Résumé L'utilisation de matériaux d'ostéosynthèse biodégradables a l'avantage d'éviter la réintervention pour extraire le matériel. Les biomatériaux de polymères polyglycolides ont été expérimentés sur plus de 3 600 animaux de laboratoire avant leur introduction en pratique clinique. Depuis 1984 nous les avons utilisés comme matériau d'ostéosynthèse dans près de 1 700 cas parmi lesquels 880 cas de fracture malléolaire, 226 cas d'ostéotomie en chevron pour hallux valgus, 65 cas de fracture de la tête radiale et 54 cas de fracture de l'olécrane. Parmi les 800 premiers cas traités par broches biodégradables nous avons obtenu des résultats favorables et sans incidents dans 91 pour cent des cas. Il y eut 7 cas de fixation défaillante nécessitant une réintervention. Il y a eu 7 cas d'infection superficielle et 3 cas d'infection profonde. Nous avons observé la formation d'une collection séreuse sous-cutanée sans influence sur le résultat radiologique ou clinique dans 52 cas (6,5 %). Au vue de ces résultats et compte tenu des avantages économiques et psychologiques des matériaux biodégradables (pas de réintervention), on peut penser que l'usage de biomatériaux rivalise favorablement avec l'usage de matériaux conventionnels dans certains types d'ostéosynthèse.
Utilization of biodegradable implants in the surgical treatment of fractures and osteotomies
Summary The utilization of biodegradable implants instead of metals in orthopaedic surgery abolishes the need to remove the fixation material. For this study biodegradable rods and screws of self-reinforced polyglycolide, polylactide and lactide-glycolide copolymer were developed and manufactured. The clinical introduction of these implants was preceded by thorough experimental studies with 3 600 animals. From November 1984 the developed biodegradable method of osteofixation was used in 1 700 operations. These included 880 displaced malleolar fractures, 226 chevron-osteotomy for hallux valgus, 65 displaced fracture of the radial head, 54 displaced frature of the olecranon and other fresh fractures or orthopaedic operations. In the first 800 cases operated on using self-reinforced polyglycolide rods the postoperative course was uneventful (91%). Because of failure in the fixation reoperation was needed in 7 cases. A superficial wound infection was observed in 7 cases, deep infection in 3 and transient fluid accumulation in 52 cases (6,5%). Fluid accumulation did not influence the radiological or clinical end-result. The advantages of biodegradable fixation are many-sided. There is a costbenefit and clinical capacity is free for other use, and psychological advantages must be emphasised because removal of implants is not needed. The over all results of this study were considered favourable.
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