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1.
OBJECTIVE: To investigate the relationships between changes in splanchnic and systemic haemodynamics in liver cirrhosis. DESIGN AND METHODS: Abdominal and peripheral duplex-Doppler sonography and Doppler echocardiography were performed in 42 cirrhotic patients with (group A, ascitic) or without ascites (group NA, non-ascitic) and in a control group of 36 healthy volunteers. RESULTS: There were significant differences (P < 0.05 at ANOVA) between the three groups in portal vein flow velocity (controls, groups NA and A, respectively, 29.2, 21.4 and 20.0 cm/s), portal diameter (9.3, 12.2 and 12.0 mm), superior mesenteric artery (SMA) resistance index (RI) (0.889, 0.854 and 0.816), femoral artery RI (0.988, 0.974 and 0.945), mean arterial pressure (MAP) (101.4, 102.0 and 87.3 mmHg), peripheral vascular resistance (1579, 1404 and 1094 dyn/cm5/s) and cardiac index (CI) (2.91, 3.46 and 3.77 l/min/m2). Multiple regression analysis identified renal interlobular- and SMA RI (respectively, r = -0.58 and r = 0.51) in group A as the two regional vascular beds correlated to MAP. CONCLUSION: The deterioration of the cirrhotic hyperdynamic circulation in the presence of ascites and the correlation between MAP and mesenteric and renal resistances are consistent with the peripheral arterial vasodilation hypothesis. The positive correlation between MAP and SMA RI in ascitic patients shows a link between this region and the general circulation. This seems to suggest that splanchnic hyperafflux plays a part in the formation of ascites.  相似文献   

2.
Stage-II alcoholics were examined 1-2 weeks after drinking periods, as were alcoholics during remissions lasting for 0.5 to 6 years. EEG was recorded by 10 symmetrical leads: prefrontal, central, motor, sincipital, and temporal. Analysis of EEG correlations revealed reliable differences between the two groups in the total level of synchronism of cortical biopotentials, in activities of different regions, and in time course of relationships of various areas during hyperventilation and without it. The data may be used as objective criteria in assessment of the degree of a pathologic process in the CNS and for differentiating the patients by this sign for further differentiated therapy.  相似文献   

3.
4.
BACKGROUND: We evaluated brain tissue oxygen pressure (PO2), carbon dioxide pressure (PCO2) and pH during ischemia with brain temperature at 35 degrees and 18 degrees C in the same patient. METHODS: Surgery was performed in a 60-year-old woman to clip a large aneurysm in the left internal carotid artery (ICA). A Paratrend 7 probe measuring PO2, PCO2, and pH was inserted into tissue at risk for ischemia during ICA occlusion and brain protection was provided with 9% desflurane. One week later, hypothermic circulatory arrest with brain temperature at 18 degrees C was performed for aneurysm clipping and tissue measurements were obtained during ischemia and rewarming. RESULTS: At 35 degrees C, ICA occlusion for 16 minutes produced tissue hypoxia (PO2 = 0) and acidosis (pH = 6.70). The rate of increase of hydrogen ion (H+) reached 50 nEq.L(-1).min(-1) during ICA occlusion and there was a slow recovery of acidosis at the end of the ischemic period. During hypothermic circulatory arrest, tissue PO2 was sensitive to decreases in blood pressure and decreased rapidly during exsanguination. Although tissue pH decreased to 6.5 with 30 min of no pump flow, the rate of H+ increase during hypothermic arrest was one-third of that seen during ischemia at 35 degrees C. During rewarming from profound hypothermia, two phases of recovery from acidosis were observed, one during CO2 clearance and one after tissue reoxygenation. Recovery of acidosis occurred sooner at 18 degrees C than at 35 degrees C. CONCLUSIONS: These results show that tissue acidosis develops more slowly and recovers more rapidly with hypothermic ischemia. This may be an important mechanism of reduced ischemic injury during hypothermia.  相似文献   

5.
Propofol decreases intraocular pressure (IOP) and the IOP response to laryngoscopy and intubation, but the mechanisms responsible for this effect have not been reported. The present study examined the effect of propofol on IOP, intraocular fluid formation and outflow facility, and intraocular compliance. Twenty-two white New Zealand rabbits were anesthetized with halothane (0.8%-1.0% inspired concentration) in nitrous oxide (2 L/min) and oxygen (1 L/min). Muscle paralysis was established with pancuronium, and the lungs were mechanically ventilated through a tracheal tube. Twelve rabbits examined under these conditions served as controls. In the treatment group (n = 10), 6 mg/kg propofol followed by 18 mg.kg-1 x h-1 propofol intravenously was added to halothane/nitrous oxide/oxygen anesthesia. In both groups, a series of intraocular infusions was made via a 30-gauge needle in the anterior chamber, and IOP, the rate of aqueous humor formation (Fa), and trabecular outflow facility (Ctr) were determined using conventional analysis. These same measures, as well as intraocular compliance, were determined using a new method of analysis adapted from the manometric technique for determining cerebrospinal fluid dynamics. IOP was 11.3 +/- 1.8 mm Hg (mean +/- SD) in halothane-anesthetized controls and decreased to 9.4 +/- 2.2 mm Hg when propofol was added to halothane anesthesia (P < 0.05). By conventional analysis, Fa was 2.82 +/- 0.94 microL/min and Ctr was 0.121 +/- 0.044 microL.min-1 x mm Hg-1 in controls. After addition of propofol, Fa decreased by 24% to 2.15 +/- 0.62 microL/min (P < 0.05) and Ctr decreased by 18% to 0.099 +/- 0.034 microL.min-1 x mm Hg-1 (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
This study examined the relationship between the constructs of leadership, as operationalized through the Leadership Personality Survey (LPS), and followership, as operationalized by the Power of followership Survey (PFS). The LPS is based on the 5-factor model of personality that is widely regarded as the premier model for understanding trait personality dimensions. The PFS is based on R. E. Kelley's (1992) model of followership styles. Data were collected from 130 students at a military college as part of their involvement in an academic course on leadership. Correlational analyses revealed numerous significant positive relationships between these 2 con- structs. Regression modeling provided insight into the relations of personality dimensions and followership. Limitations to this study and implications of these findings as well as future research directions are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

7.
This paper concerns the degree of indirect reduction in a burden rising substantially in an oxygen blast furnace. It studies the pellet, sinter and a mixture of both in different cases. The paper concerns experiments on single particle load softening to investigate the microstructural evolution of different burdens during the softening and melting process. The results of the experiments show that the degree of reduction impacted the softening and melting behaviour. In the case of a low degree of reduction, a slag phase substrate and a myrmekitic iron structure were formed on the periphery area of the molten burden, whereas slag phase substrate and disperse island wüstite structure were formed in the centre area. Both peripheral and central areas had a slag phase substrate and myrmekitic iron texture. The slag–iron distribution had a structure in which the slag phase was cut in the metal iron phase. The content of 2FeO.SiO2 as a low melting point phase in the slag decreased sharply, and this resulted in the increase in slag–iron separation temperature. The variation of the Ca/Si ratio in the interface between the pellet and the sinter indicated that enhancement of the reduction degree caused the initial temperature of the interaction in the mixed burden to rise and the interaction distance to decrease.  相似文献   

8.
Antidiuretic and oxytocic activities of venous blood plasma and liquor of ambient cistern of the cerebrum were studied in chronic experiments on alert dogs at different levels of hydration. Liquor was found to have oxytocic activity and practically no antidiuretic activity at ordinary hydration and after two days of thirst. After three days of thirst, dog's liquor caused antidiuretic reaction in rats anesthetized with alcohol, the reaction being lesser than those caused by simultaneously received plasma samples. Liquor displayed an obvious antidiuretic reaction similar to that of vasopressin after prolonged i.v. administration of hypotonic NaCl solution, while plasma samples only had the diuretic effect.  相似文献   

9.
The thyroids of primary thyrotoxicosis patients prepared for partial thyroidectomy with propranolol contained much more lymphoid infiltrate than those prepared with carbimazole. No relation was found between the extent of lymphoid infiltrate in the thyroid and the development of postoperative hypothyroidism either between or within the two drug treatment groups. This study has shown that the extent of thyroid infiltrate should not be used as the major factor in predicting hypothyroidism after subtotal thyroidectomy for primary thyrotoxicosis.  相似文献   

10.
We investigated a link between hemoglobin primary structure, hemoglobin hydrophobicity-hydrophilicity, and erythrocyte water content in various mammalian species. Some hemoglobin molecules, particularly those of the camel and camelids, contain more charged amino acid residues and are more hydrophilic than the hemoglobins of human and a number of other mammalian species. To test the in vivo significance of these alterations of hemoglobin primary structure, we determined the osmotically unresponsive erythrocyte water fractions in mannit solutions of various osmolarities at 4 degreesC. Among the species investigated, the size of the osmotically unresponsive erythrocyte water fraction relates in a positive linear way to hemoglobin hydrophilicity. The extreme low total erythrocyte water content of camel erythrocytes (1.1-1.3 g water/g dry mass) may be explained by a comparatively high osmotically unresponsive erythrocyte water fraction. It is proposed that alterations of hemoglobin sequences of camel and camelids may be the part of a natural selection process aimed at protecting these animals against osmotic dehydration in arid environments.  相似文献   

11.
Ion and water balance as well as flux balance in the animal cell, equilibrated to anisosmotic solutions, are computed for a cell model supplied by Na,K-ATPase pump, electroconductive ion channels and symporters Na-Cl, K-Cl and NaK2Cl. It is shown how the potency of each of the principal transporters to regulate cell volume depends on such conditions as the state of other ion transporters and channels, initial ion distribution and membrane potential. The obtained data are applied to studying changes in cation and water balance in the Jurkat lymphoid cells equilibrated to hyposmotic solutions. It is concluded that a steady state volume regulation in Jurkat cells, maintained in hyposmotic media 180 mosM for up to 24 h, is achieved due mainly to non-ionic mechanisms. Under the lower osmolarity of the media, 155 mosM, the ionic cell volume regulation occurs. The increase in PCl and/or the decrease in Na-Cl symport (or its equivalent, e.g. Na/H and Cl/HCO3 exchange) are considered as the most probable cause of the long-term volume decrease in lymphoid cells.  相似文献   

12.
AIMS/MATERIAL: Hepatitis C virus (HCV) genotyping was performed in 213 anti-HCV-positive patients with chronic liver disease ranging from minimal histological changes to hepatocellular carcinoma. One hundred and twenty-two patients had non-cirrhotic chronic active or persistent hepatitis (including 29 who were asymptomatic with persistently normal ALT levels) (chronic liver disease group). The other 91 had hepatocellular carcinoma and, in all but three cases, cirrhosis (hepatocellular carcinoma group). RESULTS: The overall prevalence of HCV variants was: 54.9% type 1b, 37.8% type 2, 2.5% type 1a, 2.0% type 3a, 2.0% type 4a. The genotype distribution showed no relation to the stage (chronic liver disease vs. hepatocellular carcinoma) or severity (chronic active vs. chronic persistent hepatitis) of the liver disease, or to the duration of the disease (<10 years vs. >10 years). Within the hepatocellular carcinoma group, the duration of type-1b disease was similar to that of type-2 infections. Ages at the time of infection and genotype were both independently associated with progression to cirrhosis and hepatocellular carcinoma, but multivariate analysis revealed that the effect of age was much stronger than that of genotype 1b. CONCLUSIONS: The predominance of HCV type 1b in this study reflects the higher frequency of this variant in our area. Our findings indicate that infections caused by each HCV genotype are capable of progressing to hepatocellular carcinoma.  相似文献   

13.
The learned helplessness model of depression in rats was tested. It was hypothesized that 5'-ectonucleotidase (NT), ascorbate, and antibody to sheeps' red blood cells (SRBC) are significantly reduced in rats who experienced uncontrollable shock, compared with rats who did not receive shock or could control it. During a learned-helplessness manipulation, antibody response to SRBC and NT values were unaffected. However, tissue ascorbate stores fell significantly, by 20-30%. The lack of effects on antibody responses and NT are discussed n terms of the acute nature of the stressor used in this model, as opposed to the more chronic stressors that have occurred in the human model.  相似文献   

14.
BACKGROUND: Santiago is a city with a high degree of environmental pollution caused by particulate matter and ozone, producing adverse effects in the respiratory system. AIM: To compare respiratory symptoms and cough reflex in adults from Santiago and from a rural area with low levels of environmental pollution. SUBJECTS AND METHODS: One hundred twenty six non-smoker adults from Santiago and 116 from a rural area with low levels of pollution answered a respiratory symptom questionnaire. Of these 101 subjects from Santiago and 116 from the rural area inhaled doubling concentrations of capsaicin from 0.5 to 500 microM or until five coughs were elicited. The lowest concentration eliciting 2 or more coughs (CD2) or 5 or more coughs (CD5) was recorded. Levels of environmental particulate matter were also recorded in both locations. RESULTS: Levels of particulate matter were 102 +/- 41 and 64 +/- 24 micrograms/m3 in Santiago and the rural area respectively. People from Santiago had higher rates of throat clearing, cough and phlegm. CD2 geometric mean and confidence limits in Santiago and the rural area were 6.9 (5.2-7.4) and 2.8 (2.7-2.9) respectively (p < 0.001). No differences in CD5 were observed between both locations. Multivariate analysis disclosed the variable location (city) as the only independent predictor of respiratory symptoms. CONCLUSIONS: The increased CD2 found in Santiago suggests that the higher rates of respiratory symptoms related to air pollution can be associated to a decreased sensitivity of the cough reflex.  相似文献   

15.
Gastric fistula rats (n = 79) were either left as unstressed (fistula closed) controls or gastric secretion, microcirculation (MBF), mucosal stress ulcers were studied in secretory rats subjected to zero (= freely movements allowed), mild, severe restraint stress for 8 h. In all rats gastrin in portal vein and aorta was measured in addition after discontinuation of either protocol. Acid secretion and MBF are progressively reduced by increasing stress. Pepsin and sodium are elevated with severe, acid concentration with mild stress. Pepsin and sodium are elevated with severe, acid concentration with mild stress. Serum gastrin (controls - aorta 53+/- SEM 5, portal vein 73 +/- 9 pg/ml) rises sharply in portal and systemic blood with institution of acid diversion via the outside (zero stress - 136 +/- 21, 398 +/- 98 pg/ml), but declines with increasing stress (severe stress - 82 +/- 16, 101 +/- 27 pg/ml) despite otherwise identical experimental conditions. It is concluded that (1) acid secretion rate and MBF are lowered by stress, but stress ulcers are associated with either increased acidity (mild stress) or peptic activity (severe stress) of gastric juice in the absence of elevated gastrin, (2) enhanced sodium fluxes via gastric lumen and lower acid suggest disruption if mucosal barrier by severe stress, and (3) restraint stress ulcers may be the expression of a combination of disturbances, mainly of metabolic and endocrine nature.  相似文献   

16.
Alloxan diabetes of various degree of severity was accompanied in rabbits by an increase in cholesterol and triglyceride level and, also by a progressive increase in the concentration of prebeta-lipoproteids in the blood serum. Feeding rabbits with alloxan diabetes with cholesterol for one month led to earlier and more pronouned atherogenic shifts in the organism than in control animals with the intact beta-cells of the pancreas.  相似文献   

17.
Photon scattering angular distributions from various animal tissues were measured at two energies of a monochromatic synchrotron x-ray beam. Two plastics and human breast tissue were also measured. From these two measurements, the molecular coherent scattering form factor of each material was extracted. A new data analysis technique that uses Monte Carlo based corrections for air scattering, incoherent scattering and multiple scattering was used. The form factors of the 16 materials are presented in tabular form, suitable for use in computer calculations.  相似文献   

18.
OBJECTIVE: To measure total body water (TBW) content in horses, using deuterium oxide (D2O) dilution. ANIMALS: Six 8- to 10-year-old healthy untrained mixed-breed horses, weighing (mean +/-SD) 503.4 +/- 64.0 kg. PROCEDURE: After a 12-hour nonfeeding period, 6 horses were given D2O (0.14 g/kg of body weight) via nasogastric tube. Blood samples were collected from a preplaced indwelling jugular vein catheter prior to and 1 to 8, 10, 12, 14, and 24 hours after administration of D2O. Blood samples were centrifuged immediately, and plasma was collected and stored at -70 C until analysis. The D2O content in plasma was measured by zinc reduction to deuterium gas. The resulting gas was measured, using an isotope ratio mass spectrometer. RESULTS: Deuterium oxide was rapidly absorbed from the gastrointestinal tract of all horses, and reached peak (mean +/- SD) plasma concentration (1,454.4 +/- 163 delta D/ml or parts/thousand) 1 hour after administration. Plasma concentration decreased slowly during the next 2 to 3 hours, then remained statistically constant from 2 to 5 hours (early plateau phase) and 3 to 7 hours (late plateau phase) after administration. Mean +/- SEM TBW content was 623.0 +/- 2.2 ml/kg (62.3% of body weight) for the early plateau phase and 630.3 +/- 2.2 ml/kg (63.0% of body weight) for the late plateau phase. CONCLUSION: Deuterium oxide dilution appears to be of value for measurement of TBW content in horses, and has a 4-hour plateau effect. Equilibration of D2O with large intestinal water may be the reason for the prolonged equilibrium time and plateau effect seen in these horses. CLINICAL RELEVANCE: Deuterium oxide appears safe and efficacious for determining TBW content in horses and may be helpful for determining changes in TBW content during exercise and disease.  相似文献   

19.
Report of an infant with aplasia of the proximal part of the fibula on both sides; by our knowledge the second observation in the literature. Furthermore the infant shows an aplasia of the thyroidea, a coarctation of the aorta, an atrial septal defect and an intraperitoneally situated ascending as well as descending colon.  相似文献   

20.
讨论了炼铁生产中需要准确测量和严格控制的水分,包括:烧结混合料水分、球团生球水分、喷煤的制粉烟气水分、煤粉水分、高炉的鼓风湿分、炉顶煤气水分、湿式洗涤煤气水分、干式除尘煤气水分及露点,以及焦炭水分等.提出了各水分测量和控制中存在的问题和解决的方法.  相似文献   

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