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11.
Blood flow: a mediator of ovarian function   总被引:1,自引:0,他引:1  
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On the basis of own observations of courses the author adopts a definite attitude to the early symptomatology of the rheumatoid arthritis. During the first weeks of the rheumatoid arthritis the following symptoms are found: articular syndromes, more frequently in form of obstinate polyarthralgias, mono-oligoarthritis, accompanied by morning rigidity and accelerated BSR as well as impairment of the general condition. In the majority of the patients only the tentative diagnosis rheumatoid arthritis may be made. After a one to three months' course of the disease the diagnosis becomes more probable. It is above all based on constancy and symmetry, characteristic localisation of the articular process, morning rigidity, radiologically paraarticular loosening of the structure and morphological symptoms of an acute and subacute synovialitis. 6 to 12 months after the beginning of the disease a clinical picture forms which allows to make the diagnosis of a certain or classical rheumatoid arthritis in accordance with the criteria of the ARA. The occurrence of a high activity of multiple affection of the joints (permanent symmetrical polyarthritis including the small joints of the hands and feet), distinctive morning rigidity, high fever and much accelerated BSR, beginning with the first weeks of the disease, speaks for the possibility of the development of an arthrovisceral form of the course of rheumatoid arthritis.  相似文献   
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1. Some features of the osmoregulatory mechanism are compared in four populations of Paranephrops zeal andicus White collected form freshwaters of different ionic concentrations. 2. Crayfish from freshwaters of ca, 2-0 mM-NaCl concentration show a sustained decrease in blood concentration of ca. 8% when placed in 0-2 mM-NaCl. 3. Populations from freshwaters of ca. 0-2-0-4 mM-NaCl show lower rates of net salt loss in distilled water and higher rates of net salt uptake form dilute NaCl solutions than do populations from freshwaters of ca. 0-8-2-0 mM-NaCl. 4. Renal salt losses over the first 24 h in distilled water account for ca. 18% of the total salt loss. 5. It is suggested that P. zealandicus from environments of lowest concentration shows a similar degree of adaptation to freshwater as do crayfish of the northern hemisphere. It differs in possessing a substantially higher blood concentration.  相似文献   
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The critical transmural pressure (Ptm) is defined as the transmural pressure of the airway at the site where and when flow is limited during a forced expiration. According to the presented theory, the maximal expiratory flow (Vmax) can be calculated from the relation between Ptm and the corresponding cross-sectional area of the airway (A). By means of a pitot-static tube, Ptm-A curves were constructed for several locations in the elastic airway of a mechanical model. From these curves local Vmax was calculated at different values of Ptm and compared with actual flow, i.e. measured Vmax for the entire airway. In the downstream part of the airway, the actual flow equalled calculated Vmax at most Ptm values. The site of flow limitation, being the most upstream point where actual flow equals calculated local Vmax could therefore be located. Theory and experiments showed positive as well as negative Ptm not influenced by change in upstream or downstream resistance. Flow limitation could therefore be initiated at distending as well as compressing pressures across the wall of the airway. V was regarded as a function of Ptm and the elastic recoil pressure of the lung (Pel). Measured and calculated iso-Pel, Ptm-V curves agreed well with one major exception: when Ptm less than Ptm measured curves were distorted due to a concomitant downstrean compression of the collapsible airway.  相似文献   
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The efficacies of calcium lactate and chlorine washing treatments of fresh‐cut lettuce and carrots were compared during storage at 4 °C over 10 days. The gas composition of packages, colour, enzyme activity, texture, sensory attributes, microflora and levels of ascorbic acid and carotenoids were evaluated at 1, 3, 7 and 10 days. Calcium lactate treatment was not significantly different to chlorine treatment (p < 0.05) in terms of maintaining colour, texture and acceptability of fresh‐cut lettuce and carrots during the entire storage period. The washing treatments did not affect levels of ascorbic acid of fresh‐cut lettuce or carrots. Carotenoid levels were higher in calcium lactate‐treated carrots than chlorine‐treated samples at the end of storage. Mesophilic, psychrotrophic and lactic acid bacteria counts were not significantly different between treatments for both vegetables. Copyright © 2005 Society of Chemical Industry  相似文献   
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A significant amount of logging residues is available for recovery in clear-cut areas. The forest residues’ potential has usually been estimated using biomass models. In Norway spruce (Picea abies) dominated stands, a large share of material is left on site especially due to dropping of needles as residues are left on site to dry in small heaps. In this study, we compared the measured dry weight of logging residues at a power plant with the potential biomass estimations made at a stand level. The study was performed in eight Norway spruce dominated stands, three of which were located in eastern Finland (North Karelia region) with the remainder being in Central Finland. The dry weights of branches, needles and stem tops were estimated using biomass models developed for individual trees by Repola et al. [1]. These dry weights were also compared with Swedish biomass models produced by Marklund [2]. The diameter and tree height information of each harvested tree served as input data in these model-based computations. Tree diameter information was obtained straight from the harvester’s stem value files, while the height information was obtained from models using the data from the stem value files as input. Inventory data before logging was used as a control material for harvester based estimates to spot possible measurement errors on the harvester measurement data. In addition, inventory data were used to get the crown height information, which was not available in the harvester measurement data. It was found that the average recovery rate was approximately 62% when applying Repola’s et al. [1] models and 61% when applying Marklund’s [2] models. However, variation between the logging sites was high. According this study, at least a third of the residues remains on the logging site if they are seasoned during the spring and summertime in small heaps.  相似文献   
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We investigated the effect of weekends and school holidays on the daily frequency and severity of respiratory and other symptoms among children attending schools with (index) or without (reference) moisture damage in Spain, the Netherlands, and Finland. Throughout 1 year, parents of 419 children with a respiratory condition attending index (n=15) or reference (n=10) primary schools completed three symptom diaries. We assessed associations between lower respiratory tract, upper respiratory tract or allergy, and other symptom scores and school day, weekend, or summer holiday using mixed regression models stratified by country and moisture damage. We evaluated interactions between moisture damage and type of day. We combined country‐specific estimates (incidence rate ratios [IRRs] and 95% confidence interval [CI]) in meta‐analyses. Symptom scores were lower during weekends and holiday. Lower respiratory tract symptoms were statistically significantly less common during holiday with strongest effect in index schools (IRR=0.7; CI=0.6–0.8). Reporting of other symptoms was more reduced during holiday in index (IRR=0.6; CI=0.4–0.9) than in reference (IRR=0.95; CI=0.8–1.2) schools (interaction P<.01). In conclusion, symptoms were less frequent and/or severe during summer holiday and weekends. This pattern was stronger among children attending moisture‐damaged schools, suggesting potential improvement in moisture damage‐related symptoms during school breaks.  相似文献   
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