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81.
82.
Clinical Oral Investigations - Retrospective evaluation of the clinical performance of tooth-supported overdentures retained by resilient telescopic crowns with occlusal clearance fit (ODRTC) in...  相似文献   
83.
High crystallinity leads to low hydrophilicity of fabric made of (poly(ethylene terephthalate)) fibers (PET) causing problems in finishing, washing, and dyeing processes. To improve these properties, the surface of PET fibers is usually modified by hydrolysis. Alkaline hydrolysis is a conventional process usually performed at a temperature higher than 100 °C for more than 1 h. However, the use of strong alkali and high processing temperatures (>100 °C) can lead to fabric damage and a negative impact on the environment. Therefore, in this paper, the possibility of hydrolysis of the PET fibers in the fabric in a sustainable, energy-efficient process was researched. The influence of low temperature (60–100 °C) and an accelerator (a cationic surfactant HDTMAC) to PET alkaline hydrolysis was studied through weight loss, the loss in breaking force, and fiber morphology. The kinetics of PET dissolution in 1.5 mol cm−3 NaOH at low temperature with and without the addition of HDTMAC was determined and the activation energy was calculated according to the theoretical model. It has been confirmed that PET hydrolysis can be carried out in 1.5 mol cm−3 NaOH with the addition of HDTMAC as an accelerator at 80 °C for 10 min. This process is more economically and energetically acceptable than the conventional process, and is therefore more sustainable.  相似文献   
84.
Our data support the contention that biliary bypass combined with gastric bypass is the treatment of choice for the majority of patients with adenocarcinoma of the pancreas. Compared with resection, operative morbidity and mortality rates were lower, length of hospitalization was shorter, and the cost of treatment was lower. There was no significant difference in survival. In choosing candidates for resection, the surgeon must balance the meager chances for cure (less than 1 percent) with the considerable operative hazard and the risk of lethal, costly complications. In our view, resection should be considered only for physiologically young patients with small localized lesions. These patients should be referred to surgeons specializing in pancreatic surgery who have had operative mortality rates of less than 10 percent. Pancreatic resection must, therefore, be deprived of its appeal as a procedure to which every surgeon must aspire.  相似文献   
85.
Lipofilling is becoming part of the breast reshaping after quadrantectomy or mastectomy in breast cancer patients, but there are open questions of its safety.  相似文献   
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1. The rate constant for Na efflux from the oocyte calculated from (d/dt) (ln [Na*]i]) is only approximately 52% of that calculated from (d/dt)[(ln(d[Na*]i)dt)]. The difference may be interpreted by supposing that 48% of the internal Na of the oocyte is either bound to proteins or sequestered in cell organelles.2. The mean rate constant for Na efflux was 6·4 × 10-3 min-1 corresponding to an apparent Na efflux rate of 13·3 p-mole/cm2.sec. When this is corrected for the increase in surface area produced by microvilli the true efflux rate is 1·1-1·3 p-mole/cm2.sec.3. The action of ouabain (1-5 μM) appears to involve two different effects: (a) there is 48-65% inhibition of the membrane Na pump, and (b) there is a release of some of the sequestered Na in the cell.4. Removal of external K causes a 40% reduction in Na efflux although this value may be an underestimation owing to the presence of K which has leaked from the cell and may be retained near the cell surface.5. Raising the external K concentration to 15 mM reduces the inhibitory effect of ouabain by approximately a half.6. It was concluded that the Na pump in the toad oocyte may have a slightly lower level of activity than that in frog muscle, but that its general properties are similar to those in frog muscle and some other animal cells.  相似文献   
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Bentur L  Beck R  Berkowitz D  Hasanin J  Berger I  Elias N  Gavriely N 《Chest》2004,126(4):1060-1065
BACKGROUND: Chronic cough in babies is often associated with bronchial hyperreactivity (BHR). The objective documentation of BHR in babies is difficult, and acoustic methods have been described (provocative concentration of a substance causing wheeze) for conducting bronchial provocation tests (BPTs). We conducted a study to evaluate automatic computerized wheeze detection (CWD) in determining BHR in young infants with prolonged cough, and its correlation with the subsequent development of wheezing. METHODS: Infants aged < 24 months with prolonged cough (ie, > 2 months) underwent acoustic BPTs with the response determined by CWD and auscultation by a physician. Telephone interviews with parents were conducted after 1 month and yearly for the next 3 years. RESULTS: A total of 28 infants who were 4 to 24 months old with prolonged cough were included in the study. Twenty of these infants (71.4%) had BHR as determined by a positive acoustic BPT result. In 11 of these 20 tests, the CWD occurred earlier, and in 9 tests it occurred at the same step as auscultation by a physician. Rhonchi or whistles often preceded wheezes. Seventeen of the 20 patients with BHR completed 3 years of follow-up. Of these, 14 had recurrent episodes of wheezing and shortness of breath, and 3 were well. Six of the eight adenosine-negative patients completed 3 years of follow-up and had no symptoms of BHR. CONCLUSIONS: Acoustic BPT is a technically feasible test for the detection of BHR in young infants. CWD provides an earlier detection of wheeze than stethoscope auscultation. In our group of infants, a positive acoustic BPT result had high correlation with symptoms compatible with BHR over the next 3 years.  相似文献   
90.
We have investigated natural killer cell and T cell cytotoxicity using different assays and report a dual effect of cyclic adenosine 3′, 5′-monophosphate (cAMP) on T cell cytotoxicity depending on the activation status of the effector cell and the test system in question. cAMP enhanced the capacity of pre-activated T cells to induce DNA fragmentation in the target cell, while it inhibited spontaneous T cell cytotoxicity and natural killer cell cytotoxicity in conventional assays based on 51Cr release. The enhancement was most likely mediated by the cAMP-dependent protein kinase type II (cAKII), which is the particular isoform in T cells associated with the centrosome and the microtubule organizing center (MTOC). We show the complete co-localization of the cAKII with the centrosome after conjugate formation. Furthermore, the reorganization of the MTOC following conjugate formation brings the type II kinase into close proximity with the T lymphocyte membrane area engaged in the effector-target interaction. Functional studies utilizing different cAMP-analog combinations further substantiate the involvement of the type II kinase.  相似文献   
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