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61.
E Nilsson P Sundén S Zetterquist 《Scandinavian journal of clinical and laboratory investigation》1979,39(2):171-177
A simplified thermographic technique has been developed to provide continuous leg temperature profiles by manual scanning with a noncontactile infrared radiation transducer connected to a linera potentiometer for determination of the transducer position. The clinical value of the technique in the diagnosis of acute venous thromboses has been estimated in seventy patients and thirty controls, using plethysmography and phlebography as methods of reference. The thermographic diagnosis was based on side differences in temperature levels within different segments of the limbs, as calculated from the temperature profiles by means of planimetric technique. Standardized temperature profiles from the medial side of the limbs were found to demonstrate a side difference above the reference level in fifty-seven of fity-nine patients with acute venous thromboses, which means a diagnostic sensitivity corresponding to that of conventional thermography. Skin temperature profiles were superior to plethysmography, particularly in the diagnosis of thromboses located distally. Falsely positive results were obtained, as expected, in some cases of varicose veins or acute arthritis and skin infections. The presented type of thermography has obvious qualifications as a screening method in the early diagnosis of acute venous thromboses, being far less expensive but never the less more suited for objective numerical analyses and evaluation than conventional thermography with scanning cameras. 相似文献
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E Gj?nnaess B Morken G Sandbaek E Stranden C-E Slagsvold J J J?rgensen M Nylaende M Abdelnoor R Dullerud 《European journal of vascular and endovascular surgery》2006,31(1):53-58
OBJECTIVES: To evaluate the sensitivity, specificity, positive and negative predictive value of contrast-enhanced (gadolinium) magnetic resonance imaging (CE-MRA) and colour duplex ultrasound (CDU) of lower limb arteries. DESIGN: Prospective, single centre study. MATERIAL AND METHODS: A consecutive series of 58 patients with intermittent claudication (IC) were examined with CE-MRA and CDU from the infrarenal aorta to the tibio-peroneal trunk with digital subtraction angiography (DSA) as reference. The arterial tree was divided into 15 segments, pooled into three regions; suprainguinal, thigh and knee. Sensitivity, specificity, positive and negative predictive values for significant obstructions were calculated. Cohen Kappa statistics was used to establish agreement between the three methods. RESULTS: The sensitivity (specificity in parentheses) for significant obstructions in the suprainguinal region were 96% (94%) for CE-MRA and 91% (96%) for CDU, in the thigh region 92% (95%) for CE-MRA and 76% (99%) for CDU, and in the knee region 93% (96%) for CE-MRA and 33% (98%) for CDU. CDU failed to visualize 10% of suprainguinal, 2% of thigh and 13% of knee-region arterial segments. CONCLUSIONS: Both CE-MRA and CDU are good alternatives to DSA in the suprainguinal- and thigh-region. In the knee region only CE-MRA can be relied upon as an alternative to DSA. Imaging by CDU is not suited to situations were evaluation of runoff vessels is important. 相似文献
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Sacs of the stripped and everted, isolated descending rat colon were incubated for 2 hours in presence of the following surfactants at the mucosal side: Dodecylsulphate (DDS), dioctylsulphosuccinate (DOSS), cetrimonium bromide (CTMAB), Triton X100 and deoxycholic acid (DOC). After tissue fixation, the sacs were processed for light microscopy (LM) and for scanning (SEM) and transmission (TEM) electron microscopy. All three methods revealed that DOSS (1.3 X 10(-4) and 2.6 X 10(-4) mol/l, CTMAB (5 X 10(-5) and 1 X 10(-4) ) and Triton (2 X 10(-5), 5 X 10(-5) and 1 X 10(-4) ) caused only minor or moderate changes compared to parallel controls, as did also DDS at 1 X 10(-5) and 2 X 10(-5) mol/l. DDS at 2 X 10(-4) and 4 X 10(-4) mol/l and DOC at 1.5 X 10(-4) and 3 X 10(-4) mol/l caused more prominent changes. LM showed swollen, vacuolated cells with pycnotic nuclei; many of these cells seemed to be extruded. According to SEM, cells thus affected were most abundantly localized to the normal extrusion zone at the borders of the crypt-surface epithelial cell units. DOC tended to cause a more generalized affection within the units than DDS. In spite of these deleterious effects, gaps corresponding to missing epithelial cells were not observed. TEM indicated the mechanism responsible for restoration of epithelial continuity in spite of extensive cell loss: The remaining epithelial cells seemed to flatten out and re-establish cell-to-cell contact by pseudopod formation along the basement lamina. This repair mechanism seemed to operate at a rapid rate; however, incomplete closure of cellular gaps i.e. small denuded parts of the basement lamina were occasionally observed. The results of this study are discussed in relation to a functional study under identical experimental conditions (Gastroenterol. Clin. Biol. 1981, 5, 124), in which these surfactants caused a significant alteration of normal colonic transport function. 相似文献
67.
Olof Bondestam DDS Lars Gahnberg DDS PhD Marie-Louise Sund PhD Lars Linder DDS PhD 《Special care in dentistry》1996,16(3):123-127
The potential pathogenic role of mutans streptococci in the etiology of dental caries is well-documented. Mutans streptococci are sensitive to chlorhexidine (CHX), and several methods for the clinical use of CHX have been described. An important target group for caries-preventive measures is patients with impaired salivary secretion due to the use of therapeutic drugs such as psy-chotropics. The aim of the present study was to compare two methods for antimicrobial treatment in such patients. Twenty-four volunteering patients at a hospital clinic were randomly divided into three groups: Group A, in which each participant was treated with 1.0% CHX gel in gel trays on two consecutive days, followed by application of a fluoride varnish; Group 6, in which the patients were treated with the same CHX gel as above; and Group C, which was used as a control. After treatment, there was a reduction of mutans streptococci in the two groups treated with CHX. In group A, the sames collected one, three, and five weeks after the treatment were significantly lower than baseline values. No clearcut reduction of the number of mutans streptococci was observed in the subjects not treated with CHX. These data indicate that treatment with CHX gel in gel trays is superior to polishing the teeth with CHX gel. From a clinical point of view, our observations suggest that it is important to monitor the effect of antimicrobial treatment individually in order to optimize preventive programs in patients with impaired salivary secretion. 相似文献
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1. Blood pO2 along the rete of eel has been investigated with a microelectrode, the swim-bladder gas being replaced by air. 2. When the eel does not secrete gas, the pO2 profile is flat, whereas in actively secreting eel the pO2, along the rete has a maximum of approximately 1 atm near the bladder pole of the rete. 3. The findings confirm predictions of a mathematical model for counter current multiplication in the swim-bladder. 相似文献
70.
Abstract Tissue uptake and transepithelial permeation of 35S-sulphanilic acid were studied in the isolated guinea pig jejunal mucosa. Methoxy-3H-inulin added simultaneously served as a marker for the extracellular space and permeability of paracellular shunt pathways in the preparation. The uptake of sulphanilic acid from the blood side exceeded that from the luminal side 4–7 fold. The permeation of the acid was strongly correlated to the permeation of inulin. At 5 μM and 2.5 mM sulphanilic acid under aerobic conditions, the regression lines for the permeation from lumen to blood pass almost through the origin, while the regression lines for the permeation from blood to lumen intersect the ordinate at a positive Y-value. In anaerobiosis, at 25 mM sulphanilic acid, or with addition of p-toluene sulphonic acid only one regression line is obtained for the permeation in both directions. It is concluded that besides a permeation of sulphanilic acid across inulin- permeable shunt pathways an active transport system exists, which transfers the acid from the blood to the luminal side. This system is saturable, depends on aerobic energy and exhibits mutual inhibition by a structurally related compound. The results are comparable to those previously obtained with cardiac glycosides and quaternary ammonium compounds, in the same preparation. Thus, the intestinal mucosa is able to secrete the same classes of compounds which are secreted by the liver and the kidney. 相似文献