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1.
BACKGROUND: The severe types of central serous chorioretinopathy (CSC) have a chronic nature, suggesting that a pathological process persists subclinically. Indocyanine green (ICG) angiography recently revealed intrachoroidal dye leakage and its static nature in CSC. As the intrachoroidal dye leakage was suspected to be relevant to the disease process, the long-term persistence of intrachoroidal ICG leakage was examined in four patients of the severe types of CSC. METHODS: ICG angiography was performed periodically over more than three years in three patients and two years in one patient. One patient had CSC with bullous retinal detachment, and the other three had chronic CSC or diffuse retinal pigment epitheliopathy. RESULTS: Intrachoroidal ICG leakage persisted in all the patients. However, a change in location of persistent intrachoroidal leakage or disappearance of intrachoroidal leakage regardless of no progression of retinal pigment epithelial alteration was noted in one eye of two patients. CONCLUSIONS: Pathology causing intrachoroidal ICG leakage persisted subclinically for a long period. However, location and extent of the intrachoroidal leakage could change during a long-term follow-up period.  相似文献   

2.
BACKGROUND: A new method for determining cardiac output (CO, l/min) using dye dilution combined with pulse dye densitometry (PDD), based on the principle of pulse oximetry, has been developed. The aim of the study was to determine the accuracy and precision of PDD by comparing it with the thermodilution method. METHODS: A prospective study was performed in 22 patients having surgery who were monitored using a pulmonary arterial catheter. In addition to the catheter, a specially designed photodetector was placed on the nasal wing. Ten milliliters of ice-cold indocyanine green dissolved in a 5% glucose solution (0.5 mg/ml) was injected. The dye and thermal dilution curves were simultaneously measured to calculate CO. Three to six injections were performed before and after surgery. Paired data were assessed in absolute terms, and the percentage errors were calculated by the degree of agreement and compared at three levels of CO (low < or = 3.5 < medium < or = 6 < high) by analysis of variance. RESULTS: The mean and SDs of the differences between dye and thermodilution CO were 0.16 +/- 0.80 l/min or 4.5 +/- 19.6% for 191 paired data. Measurement after surgery failed in one patient. The percentage error with low CO (9.3 +/- 19.3%) was greater (P < 0.05) than those obtained with other CO. CONCLUSIONS: Pulse dye densitometry could measure CO repeatedly in patients having major surgery with the same degree of accuracy as the thermodilution method; however, a considerable degree of error was observed in some patients.  相似文献   

3.
1. The fasting plasma disappearance curve of [14C]glycocholic acid after intravenous injection was compared in nine normal subjects with that obtained 100 min after a standard liquid test meal. 2. Plasma disappearance curves of indocyanine green were determined in 13 normal subjects under the same conditions. 3. Plasma clearances were significantly increased after the meal for both [14C]glycocholic acid (median 455 ml min--1 m--2, range 376--672 increased to 704, 528--1968; P less than 0.01) and indocyanine green (359, 227--473 increased to 435, 358--985; P less than 0.01). 4. Median initial volume of distribution was unaltered, but in four subjects it was greatly increased after the meal, although no alteration in plasma volume, measured with Evans blue dye, was observed. 5. The increased postprandial plasma clearance of glycocholic acid is probably due to an increase in liver blood flow, and suggests that in health this part of the enterohepatic circulation of bile acids also varies with meals.  相似文献   

4.
5.
We compared indocyanine green (ICG) and fluorescein angiography for evaluation of choroidal neovascularization (CNV). Cast preparations of CNV induced in monkey eyes by laser photocoagulation were correlated with ICG and fluorescein angiographies of the same CNV formations. Fluorescein angiography was more effective, in general, than ICG angiography in detecting CNV; however, CNVs with subretinal hemorrhage (2 of 35 sites) were visible only with ICG angiography. In early phase ICG angiography, CNV formations that casts showed to be dense or composed of thick vessels were seen, but less dense areas were not visible. Lesions that ICG angiography revealed as leaking were not differentiated morphologically from non-leaking areas by the CNV casts. This study confirms that only ICG angiography can identify CNV hidden by subretinal hemorrhage, although fluorescein angiography is otherwise superior. Indocyanine green angiography is indicated as a valuable complement to fluorescein angiography for evaluation of CNV.  相似文献   

6.
How to measure pain is a great challenge to those who desire to control adequately such a complex experience. Standardized instruments that take into consideration the patient's own account, have been developed in order to make such a task easier. In this article we carry out a revision of the instruments used mostly for measuring postoperative pain, and we point out some of the advantages and disadvantages. We emphasize the need for specific research focusing on the measurement of surgical pain, taking into consideration the multiple dimensions of a painful experience.  相似文献   

7.
Interaction of sensitized T-lymphocytes with specific antigen, as well as several other nonimmunological stimuli, will induce the appearance of new properties in macrophages collectively referred to as "activation". The importance of macrophage activation in various physiological processes is only just beginning to be understood. A growing body of evidence strongly suggests that activated macrophages may play a dual role: firstly in protecting the host against certain interacellular pathogens, and secondly in modulating cell proliferation and adversely affecting cells with abnormal growth properties. It is expected that the ability of activated macrophages to discriminate between normal and tumor cells will receive increasing attention. If confirmed, this property may be of major importance with regard to immunotherapy of tumors.  相似文献   

8.
Genome size was determined, by nuclear Feulgen staining and image analysis, in 46 accessions of 31 species of Peronosporales (Oomycota), including important plant pathogens such as Bremia lactucae, Plasmopara viticola, Pseudoperonospora cubensis, and Pseudoperonospora humuli. The 1C DNA contents ranged from 0.046 (45. 6 Mb) to 0.163 pg (159.9 Mb). This is 0.041- to 0.144-fold that of Glycine max (soybean, 1C = 1.134 pg), which was used as an internal standard for genome size determination. The linearity of Feulgen absorbance photometry method over this range was demonstrated by calibration of Aspergillus species (1C = 31-38 Mb) against Glycine, which revealed differences of less than 6% compared to the published CHEF data. The low coefficients of variation (usually between 5 and 10%), repeatability of the results, and compatibility with CHEF data prove the resolution power of Feulgen image analysis. The applicability and limitations of Feulgen photometry are discussed in relation to other methods of genome size determination (CHEF gel electrophoresis, reassociation kinetics, genomic reconstruction) that have been previously applied to Oomycota.  相似文献   

9.
Three-dimensional structures of a representative set of more than 30 hydrogen-bonded nucleic acids pairs have been studied by reliable ab initio quantum mechanical methods. We show that many hydrogen-bonded nucleic acid base pairs are intrinsically nonplanar, mainly due to the partial sp3 hybridization of nitrogen atoms of their amino groups and secondary electrostatic interactions. This finding extends the variability of intermolecular interactions of DNA bases in that i) flexibility of the base pairs is larger than has been assumed before, and ii) attractive proton-proton acceptor interactions oriented out of the base pair plane are allowed. For example, all four G-A mismatch base pairs are propeller twisted, and the energy preferences for the nonplanar structures range from less than 0.1 kcal/mol to 1.8 kcal/mol. We predict that nonplanarity of the amino group of guanine in the G(anti)...A(anti) pair of the ApG step of the d(CCAAGATTGG)2 crystal structure is an important stabilizing factor that improves the energy of this structure by almost 3 kcal/mol. Currently used empirical potentials are not accurate enough to properly cover the interactions associated with amino-group and base-pair nonplanarity.  相似文献   

10.
The purpose of this study was to determine the contribution of the lymphatic circulation to blood volume and plasma protein restitution after hemorrhage. Splenectomized sheep were prepared with thoracic duct and vascular catheters. The day after surgery, thoracic duct lymph flow, thoracic duct lymph protein, plasma protein, mean arterial pressure, and blood volume were measured. After 12 h, awake sheep were either bled 25% of blood volume over 5 min (HEM; n = 6) or observed (SHAM; n = 5) and measurements were recorded for 48 h. In HEM, the thoracic duct protein return rate and thoracic duct lymph flow transiently decreased (0-.5 h) but were then equal to or greater than that in SHAM. In HEM, there was restitution of both blood volume and plasma protein mass approximately 12 h after hemorrhage. Both thoracic duct lymph flow and protein return rate are significant contributors to blood volume and plasma protein restitution after hemorrhage. These findings and the prior demonstration by the authors that lymphatic vessel pumping is increased after hemorrhage suggest a dynamic role for the lymphatic circulation in blood volume homeostasis after hemorrhage.  相似文献   

11.
The early changes in circulating blood volume (CBV) and volume regulating humoral factors after implantation of an electrohydraulic total artificial heart (EH-TAH) were investigated in a calf and compared with results in a sham operated control calf. CBV was measured by the dye dilution method using indocyanine green. CBV and humoral factors were periodically investigated. In the EH-TAH implanted calf, the cardiac output was estimated at 6-7 L/ min (94-109 ml/kg/min), and the aortic pressure and aerobic metabolic condition were favorable. Nevertheless, the CBV was increased to 132 and 168% of the pre-operative value (range in the control calf, 83-103%) on post operative days 4 and 8, respectively. The atrial natriuretic peptide level on days 2, 5, and 7 was 23, 170, and 240 (in the control calf, 19-61) pg/ml, respectively, and the antidiuretic hormone level was 7.3, 2.0, and 1.3 (0.5-1.3) pg/ ml, respectively. The plasma renin activity was 3.2, 3.7, and 3.1 (0.5-0.3) ng/ml/hr, respectively. The angiotensin-I and angiotensin-II levels were also increased in the EH-TAH implanted calf. It is concluded that significant water retention occurs even at sufficient cardiac output early after EH-TAH implantation. The changes in humoral factors are suggested to arise secondary to the increased CBV or other unknown factors.  相似文献   

12.
13.
Serum lipids are known to vary during the menstrual cycle. To determine if changes in plasma volume contribute to this effect, we determined serum lipids, lipoproteins, and estimated changes in plasma volume in 18 premenopausal women at the start of and at 5-day intervals after menstruation. Eleven men served as a comparison group. Changes in plasma volume were estimated from changes in hemoglobin and hematocrit. Total and low-density lipoprotein (LDL) cholesterol (mean +/- SD) increased 15 +/- 14 mg/dL (9% +/- 10%) and 11 +/- 13 (11% +/- 14%) within 10 days after the start of menstruation (P < .05) and then decreased toward baseline during the rest of the cycle. High-density lipoprotein (HDL) cholesterol increased 3 mg/dL, or 5%, (P < .05) on days 10 and 15 after menstruation. Plasma volume decreased 4% +/- 9% (P < .06) 10 days after the start of menstruation, and this maximum decrease in plasma volume coincided with peak increases in total, LDL, and HDL cholesterol. Except for an 8-mg/dL increase in LDL cholesterol at day 5, lipid changes were no longer significant after adjusting for changes in plasma volume. We conclude that alterations in plasma volume account for approximately half of the increase in total and LDL cholesterol during the menstrual cycle.  相似文献   

14.
375 Individuals from 23 HBsAg positive families were investigated in the study. The results showed that HBsAg carrier rate among blood relatives was significantly higher than non-blood relatives (P < 0.01); HBsAg carrier rate decreased with the order of the first, second and third degree relatives (P < 0.01); and the rate in the individuals living together with the probands was higher than those living apart (P < 0.01). However, the other two markers of HBV infectivity, anti-HBs and anti-HBc, did not show any differences mentioned above. The results analysed by means of dichotomy and Logistic regression model, showed that blood relationship played an important role in HBsAg carrier state. In addition, the history of sharing living facilities was related to HBsAg carrier state. The average heritability in the first, second and third degree relatives was 79.68%. The analysis of genetic model showed that HBsAg carrier state was corresponded to the characteristic of multifactorial genetic disease, excluding the possibility of genetic disease due to single gene.  相似文献   

15.
A simple, sensitive and precise isocratic HPLC method for the determination of total homocysteine in human plasma is described. The thiol compounds were liberated from plasma proteins by reduction with tri-n-butylphosphine and derivatized with a thiol-specific fluorogenic marker, 7-fluoro-benzo-2-oxa-1,3-diazole-4-sulphonate. The derivatives were separated isocratically within 7 min by reversed-phase HPLC using a Superspher 100 RP-18 column as stationary phase. By using this approach more than 200 samples a day can be assayed for total homocysteine. The method was linear up to 100 mumol/l and proved to be sensitive with a detection limit of 0.1 mumol/l and the lowest limit of reliable quantification of 0.5 mumol/l for homocysteine in buffer. Intra- and inter-assay coefficients of variation were both < 4% at a concentration of 10 mumol/l homocysteine. Similar results were obtained for homocysteine concentrations between 0.5 and 100 mumol/l. The analytical recovery for these concentrations ranged from 94.9 to 117.0%. As compared to other protocols published so far, this modified method is less complicated but equally sensitive and reproducible and allows a rapid determination of total homocysteine and cysteine in human plasma under routine conditions.  相似文献   

16.
建立了微波消解分解样品,电感耦合等离子体质谱法测定钢铁及合金中总铝和总硼的方法。采用自制的提纯装置提纯氢氟酸。借助微波消解炉,用3mL盐酸、1 mL硝酸和1 mL氢氟酸(1+1),在适宜的压力和温度下消解可将样品消解完全。铍、钪随仪器参数波动引起的信号变化规律与硼、铝的相同。以被测样品主量元素和样品分解的酸进行基体匹配,采用Be和Sc内标补偿仪器漂移和校正基体效应。用本法测定样品中总铝和总硼,快速、简便、精密度好,测定结果与认定值符合较好,适于测定钢铁及合金中质量分数为0.0001%~0.1%总铝和总硼。  相似文献   

17.
A simplified enzymatic-gravimetric method for total dietary fiber (TDF) determination has been published and used in the Food Composition Laboratory of the U.S. Department of Agriculture since 1988. THis method gives comparable results to AOAC Official Methods 985.29 and 991.43 but the AOAC methods use 100 degrees C (water bath) to gelatinize the sample and a combination of alpha-amylase and an amyloglucosidase to hydrolyze starches, whereas the simplified method incorporates an autoclaving step (121 degrees C) for gelatinization followed by incubation with only amyloglucosidase. The simplified method omits protease hydrolysis and does not require any pH adjustment. Overall, the simplified method cuts cost and is less labor intensive. An interlaboratory study was conducted to validate this method. Blind duplicates of six sample (baked beans, corn bran, roasted peanuts, cooked potatoes, white bread with reduced calories, and cooked white rice) were sent to 11 laboratories. The reproducibility relative standard deviations of the TDF values (without outliers) ranged from 3.46 to 27.6%. The repeatability standard deviations ranged from 0.91 to 14.6%.  相似文献   

18.
The disposition of lidocaine and indocyanine green was studied in 6 individuals during and after recovery from an episode of acute viral hepatitis. Both compounds are highly cleared from the blood by the liver so that clearance of both should be sensitive to changes in hepatic blood flow. During the acute phase of illness, clearance of indocyanine green decreased without apparent change in volume of distribution, whereas clearance of lidocaine, decreased in 4, did not change in 1, and increased in 1 during the acute phase of hepatitis. Volume changes for lidocaine were also variable. We observed no significant correlation between any parameters of lidocaine disposition and any of several tests of liver function or any parameters of indocyanine green disposition. The absence of correlation between pharmacokinetic parameters of the disposition of lidocaine and indocyanine green indicates that the influence of hepatic disease on the hepatic processes that lead to the elimination of each compound is not predictable. No useful clinical correlates are now available by means of which to predict lidocaine disposition in patients with altered hepatic function.  相似文献   

19.
The methods of serum determination of specific IgE to different allergens have showed lower diagnostic sensitivity than the alternative in vivo methods, the skin tests. The CAP system from Pharmacia, owing to its solid phase, has ameliorated this disadvantage, showing in various studies greater diagnostic sensitivity than the classic RAST, without affecting specificity. However, this system is still semi-automatic and requires daily calibration. UNICAP 100 is a completely automatic autoanalyser for total IgE, specific IgE and Eosinophil Cationic Protein, which combines the high sensitivity of the CAP system with complete automation and monthly calibration. The aim of the present study is to assess the practicality and reliability of UNICAP 100, when compared to the CAP System, for the determination of total IgE and specific IgE, as well as the sensitivity and diagnostic specificity; using as a reference skin tests in 150 paediatric patients. The coefficients of variation in the study of intraseries imprecision ranged between 2.1% and 3.6% for total IgE and between 2.2% and 5.1% for specific IgE, depending on the allergen and the level studied. The intraseries imprecision ranged between 3.3% and 7.7% for total IgE and between 5.2% and 8.9% for specific IgE. The coefficients of correlation of the study of interchangeability with the results of the CAP System varied between 0.985 and 0.998, all the allergens tested (9) being interchangeable. Finally, the diagnostic sensitivity varied between 70% and 95% and the specificity between 87% and 100%. In conclusion, UNICAP 100 showed results that were interchangeable with the CAP System, noticeably improving the benefits owing to its complete automation and its calibration system.  相似文献   

20.
The determination of the volume fraction of a second phase in a multiphase sample by X-ray diffraction becomes more difficult if the diffracting planes have a preferred orien-tation. Lopata and Kula have described a method of treating this problem using complete pole figures for each of the phases. With some samples, it is not always possible or con-venient to obtain data over the full hemisphere. Equations and an example are given which require X-ray data over a limited range of approximately 0 to 75 deg. This can be ob-tained by reflection without a specially cut sample or transmission data. A series of Legendre polynomials are fitted to data collected while spinning the sample about its nor-mal. An extrapolation is made possible by introducing two conditions on the end points which must be satisfied if the extrapolation functions are to be valid.  相似文献   

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