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991.
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993.
Thoracic empyema (development of suppuration in the thoracic cavity, usually after pneumonectomy) remains a serious complication which is difficult to treat. Failure of classical procedures (lavage-drainage) in the treatment of certain forms of pleural empyema (post-pulmonary resections), with or without associated fistula, led the authors to use the pedicled omental flaps filling material for the chronic empyema cavity. They report their experience (6 cases over a period of 4 years) and define the indications. Omentoplasty has a real place, next to myoplasty, in the therapeutic arsenal for chronic empyema due to its detersion capacity, particularly useful in a "septic" context and because of its volume which is usually sufficient in retracted cavities. The existence of an associated bronchial fistula, history of radiotherapy, posterolateral thoracostomy (sectioned latissimus dorsi) are additional reasons to prefer omentoplasty over myoplasty.  相似文献   
994.
OBJECTIVE: The purpose of this study was to determine whether cells acquired from individual human preovulatory follicles undergo apoptosis (physiologic cell death) and, if so, to correlate the degree of apoptosis with characteristics of the follicles or the oocytes derived from the follicles. METHODS: We devised a sensitive nonradioactive method for detecting apoptotic DNA fragmentation in small numbers of cells derived from rat atretic follicles and follicular aspirates of patients undergoing assisted reproductive technologies. RESULTS: Using this method, apoptotic DNA was detected in rat atretic follicles, with optimal detection at 10-100 ng. Furthermore, apoptotic DNA was detected in some, but not all individual human follicular aspirates from several patients, and was found in follicles that produced oocytes that fertilized and developed into embryos. CONCLUSION: Apoptosis occurs in cells from human ovarian preovulatory follicles and may be a normal physiologic process of the follicle during luteinization.  相似文献   
995.
We investigated the effect of chronic exposure (3 days) with low-density lipoprotein (LDL) and oxidized (Ox)-LDL on the unstimulated and stimulated formation of prostacyclin (6-keto-prostaglandin [PG]F1 alpha) and total inositol phosphates (IPs) by cultured bovine aortic endothelial cells. Neither basal nor bradykinin-stimulated (1 to 10 nmol/L) formation of 6-keto-PGF1 alpha was affected by LDL, except at the highest concentration of bradykinin tested (100 nmol/L). In the presence of the antioxidants N-acetyl-L-cysteine (NAC, 10 mumol/L) or vitamin E (100 mumol/L), basal and bradykinin-stimulated formation of 6-keto-PGF1 alpha was potentiated by 20 micrograms protein/mL of LDL. Ox-LDL decreased unstimulated formation of the eicosanoid from 3.1 +/- 0.2 pg/micrograms protein in control cells to 1.6 +/- 0.1 and 0.5 +/- 0.1 pg/microgram protein after 3-day incubation with 5 and 20 micrograms protein/mL of Ox-LDL, respectively (P < .05). As in the basal state, Ox-LDL decreased bradykinin-induced 6-keto-PGF1 alpha formation. NAC or vitamin E did not influence Ox-LDL-induced endothelial cell changes in eicosanoid production. IPs formation by endothelial cells increased to a similar extent in the presence of 20 micrograms protein/mL of either LDL or Ox-LDL. However, no change was apparent in the bradykinin (10 mumol/L)-induced increase in total IPs formation after incubation with the lipoproteins. The data indicate that chronic exposure to Ox-LDL abolishes the production of prostacyclin by cultured endothelial cells. The oxidatively modified lipoprotein seems to more specifically affect the prostacyclin pathway.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
996.
Event-related desynchronization (ERD) was studied in 10 young (mean age = 19.1) and 10 older (mean age = 62.8) subjects during a verbal recognition task. The attention load of the task varied according to the difficulty of discriminating between targets and distractors. EEG recorded from 29 electrodes was used to compute ERD from 14 source derivations in 125 ms intervals. Thereafter, it was displayed as spatiotemporal maps. The results show that attention influences the characteristics of EEG desynchronization. In young subjects, ERD is more pronounced and more widespread when the attentional load is high. In the elderly, differences between the two attention conditions are less marked. ANOVA reveals main effects of attention and time. The significant 'attention x time x age group' interaction confirms the presence of different brain activation patterns in the two age groups in relation to attention load.  相似文献   
997.
One hundred and seven consecutive patients presenting with significant peptic ulcer haemorrhage were randomised to endoscopic injection with 3-10 ml of 1:100,000 adrenaline (55 patients, group 1) or to a combination of adrenaline and 5% ethanolamine (52 patients, group 2). All had major stigmata of haemorrhage and endoscopic injection was undertaken by a single endoscopist. The groups were well matched with regard to risk factors. Rebleeding occurred in eight of the group 1 patients and seven in the group 2 patients; surgical operation rates, median blood transfusion requirements, and hospital stay were similar in both groups. The efficacy of either form of injection was similar whether patients presented with active bleeding or a non-bleeding visible vessel. No complications occurred. In patients presenting with significant peptic ulcer bleeding, the addition of a sclerosant confers no advantage over injection with adrenaline alone.  相似文献   
998.
999.
Reaction of bacterial adhesins with complementary receptors on the surfaces of mucosal respiratory, gastrointestinal and genitourinary cells leads to bacterial adhesion to the human body. This is the first step in the sequence of events leading to infection. It has been observed that subinhibitory concentrations (sub-MICs) of some antibiotics are able to reduce bacterial adhesion. The pharmacokinetic curves of antibiotics show that these sub-MICs are present in tissues during a typical course of therapy. This study investigated the ability of sub-MICs of seven macrolides and four fluoroquinolones to reduce adhesiveness of Staphylococcus aureus to human buccal cells. The literature generally reports data for only one antibiotic at a time. To obtain an overall view of the findings of eleven antibiotics together, the data have been normalized according to the molecular weight of each antibiotic and the dose-effect curves determined.  相似文献   
1000.
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