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1.
Rat liver was subjected to three different, disruption procedures (homogenization, explosive decompression, and Chaikoff press) and mitochondria were subsequently isolated by conventional differential Centrifugation and by zonal Centrifugation. The properties of these mitochondria were investigated by polarographic measurement of oxygen uptake and they were examined by electron microscopy. All three methods of disruption gave mitochondria which showed respiratory control. Nitrogen cavitation gave the most reproducible conditions for cell breakage and zonal Centrifugation gave good separation of subcellular organdies in extracts produced by this method. Some separation of the heterogenous mitochondrial populations was achieved by zonal Centrifugation.  相似文献   

2.
One hundred and forty-seven patients were examined by bone scintigraphy, ultrasonography and scintigraphic scan of the liver, at different times after surgical removal of a breast cancer, to rule out skeletal and hepatic metastases. At the same time as imaging procedures, serum levels of tumor markers (CEA, TPA and CA 15-3) were determined using radioimmunometric methods. One or more markers were elevated in all 13 patients with hepatic metastases; 9 out of 46 patients with bone metastases had all serum markers normal, with a sensitivity of 80%. Combined assay of the markers proved useful, TPA and CA 15-3 showing the best sensitivity in bone metastases, and all three markers in liver metastases.  相似文献   

3.
The subunit composition of human liver alpha-L-fucosidase was studied by using three different procedures for treating and electrophoresing the purified enzyme. Although the presence on only one subunit was found by conventional procedures using sodium dodecyl sulphate and urea, two non-identical subunits with mol. wts. of 59 000 and 54 000 were found when the alpha-L-fucosidase was reduced and S-carboxymethylated with iodoacetate followed by electrophoresis on polyacrylamide gels containing 0.1% sodium dodecyl sulphate and 8.0 M-urea.  相似文献   

4.
Four microbiological assay procedures (Escherichia coli, Lactobacillus leichmanni, Euglena gracilis, and Ochromonas malhamensis) for the vitamin B(12) content of rat liver and kidney tissue were compared. Significant differences in the growth response for portions of the same sample based on the same standard preparations were noted. The liver values with E. coli were strikingly higher than those obtained with the other microorganisms, about which there was rather general agreement. With kidney tissue, E. coli again gave higher values, but not as significantly high as those obtained with L. leichmannii and E. gracilis. O. malhamensis values were significantly lower. These differences were greater than were expected and could not be explained by the differences of specificity and sensitivity of the assay organisms. Several methods of sample preparation, the possible presence of an alkali-heat-stable factor, different methods of sterilization of the sample plus medium, and different chromatographic procedures were explored in an attempt to find explanations for the variations in growth response, with the thought that these various methods would clarify in what form or forms the free and bound vitamin B(12) might exist in the samples. No clear-cut explanation was found.  相似文献   

5.
Transcatheter treatment was performed in 81 patients with unresectable non-colorectal liver metastases. Effectiveness increased in the following order: hepatic artery infusion--arterial chemoembolization--combined, arterial and portal vein oily chemoembolization. The mean survival rates for these methods were 8.2 +/- 5.3, vs 11.7 +/- 12.9 vs 13.6 +/- 6.8 mo, and 1-year survival rates 29% vs 46% vs 65%, respectively. Chemoembolization with doxorubicin-in-oil and gelatin sponge was the most effective technique. Interventional radiological procedures were effective in neuroendocrine liver metastases. The mean survival, 1- and 3-year survival rates were as high as 34 mo, 100% and 80%, respectively, for hepatic metastases from resected malignant carcinoid tumors. Also good results were achieved after chemoembolization of metastatic ovarian carcinoma and arterial infusion for gastric carcinoma metastatic to the liver. Transcatheter treatment was ineffective in liver metastases from pancreatic carcinoma, gallbladder cancer, and unknown (and non-resected) tumors. The initial results of the use of interventional radiological procedures in non-colorectal liver metastases are promising, so following clinical trails are needed.  相似文献   

6.
Carbon dioxide and oxygen exchange procedures for measuring community metabolism (two open stream methods and three chamber methods) were compared on the same reach of a third-order stream. Open stream methods were complicated by high diffusion rates and yielded net community primary productivity estimates lower than those obtained with chamber methods. Chamber methods yielded variable productivity and respiration data. However, when normalized for chlorophyll a, productivity estimates from the chamber methods were within an expected range for the system. Balances of photosynthesis and respiration from the chamber methods were similar between methods and indicated that autotrophic or heterotrophic processes could dominate the system. Considerations in applying the various procedures are discussed.  相似文献   

7.
The purpose of this study was to investigate the influence of different cell extraction procedures on relative nuclear DNA content (IOD), nuclear area, and texture features of Feulgen-stained nuclei. In imprints and smears of fine-needle aspirates and suspensions from one human liver specimen, 50 diploid, 50 tetraploid, and 25 octaploid nuclei were measured from each slide. In addition, for DNA measurements, the progressive mean of IOD and tetraploid/diploid and octaploid/diploid ratios was calculated. The results show that the progressive mean of the IOD is constant after measuring 25-30 nuclei. For the three types of specimens, the IOD of diploid nuclei varied slightly. The average coefficient of variation was about 5% for the fine-needle aspirates, imprints, and suspensions. For all tissue sampling methods, the 99% confidence limits of the tetraploid/diploid ratio and octaploid/diploid ratio were within the range of 1.9-2.1 and 3.7-4.3, respectively. The nuclear area and most of the texture features showed a significant difference (p less than 0.01) between the three sampling methods in all nuclear populations. In conclusion, different tissue sampling methods have little or no effect on DNA-related IOD measurements, whereas the outcome of nuclear area and texture features is very dependent of the cell extraction procedure.  相似文献   

8.
Whole genome sequencing (WGS) shows great potential for real-time monitoring and identification of infectious disease outbreaks. However, rapid and reliable comparison of data generated in multiple laboratories and using multiple technologies is essential. So far studies have focused on using one technology because each technology has a systematic bias making integration of data generated from different platforms difficult. We developed two different procedures for identifying variable sites and inferring phylogenies in WGS data across multiple platforms. The methods were evaluated on three bacterial data sets and sequenced on three different platforms (Illumina, 454, Ion Torrent). We show that the methods are able to overcome the systematic biases caused by the sequencers and infer the expected phylogenies. It is concluded that the cause of the success of these new procedures is due to a validation of all informative sites that are included in the analysis. The procedures are available as web tools.  相似文献   

9.
Rabbit lung and liver microsomes were subjected to three procedures which decreased NADPH cytochrome c reductase activity; flavoprotein antibody, trypsin and subtilisin digestion. The effects on benzphetamine and p-nitroanisole demethylation and amine metabolic-intermediate complex formation were investigated. In general, the proteolytic digestion had a greater inhibitory effect on oxidation reactions for a given loss of NADPH cytochrome c reductase activity than did flavoprotein antibody; and of the two proteases, subtilisin, which also diminishes the cytochrome b5 reduction pathway, had a greater inhibitory effect than trypsin. Subtilisin digestion had similar effects in both liver and lung microsomes; a loss of flavoprotein without a loss of cytochrome P-450; but whereas all three oxidative reactions decreased in unison as the flavoprotein was lost in the liver, benzphetamine demethylation was less susceptible to flavoprotein depletion than the other two reactions in lung microsomes. With trypsin digestion flavoprotein was removed without loss of cytochrome P-450 only in lung microsomes; in liver microsomes the cytochrome P-450 was susceptible to tryptic degradation. In lung microsomes, benzphetamine and p-nitroanisole demethylations were less susceptible to flavoprotein loss than metabolic-intermediate complex formation.  相似文献   

10.
Tissue distribution of carnitine biosynthetic enzymes in man   总被引:1,自引:0,他引:1  
The distribution in human tissues of enzymes which convert epsilon-N-trimethyl-L-lysine to L-carnitine was studied. Existing methodology was modified and new procedures were developed to measure enzyme activities. Epsilon-N-Trimethyl-L-lysine was converted to gamma-butyrobetaine in three enzymatic steps (hydroxylation at carbon 3, aldol cleavage between carbons 2 and 3 to yield glycine and gamma-trimethylaminobutyraldehyde, and subsequent oxidation of the aldehyde) in all tissues studied (liver, brain, kidney, heart and skeletal muscle), but gamma-butyrobetaine was hydroxylated to form L-carnitine only in liver, kidney and brain. Gamma-Butyrobetaine hydroxylase (4-trimethylaminobutyrate, 2-oxoglutarate: oxygen oxidoreductase (3-hydroxylating), EC 1.14.11.1) activity in liver was dependent on the age of the subject. The activity rose from 12% in infants to 100% of the adult mean by age 15 years. No age dependence could be demonstrated for the other three enzymes studied.  相似文献   

11.
In clinical studies, we often compare the success rates of two treatment groups where post‐treatment responses of subjects within clusters are usually correlated. To estimate the difference between the success rates, interval estimation procedures that do not account for this intraclass correlation are likely inappropriate. To address this issue, we propose three interval procedures by direct extensions of recently proposed methods for independent binary data based on the concepts of design effect and effective sample size used in sample surveys. Each of them is then evaluated with four competing variance estimates. We also extend three existing methods recommended for complex survey data using different weighting schemes required for those three existing methods. An extensive simulation study is conducted for the purposes of evaluating and comparing the performance of the proposed methods in terms of coverage and expected width. The interval estimation procedures are illustrated using three examples in clinical and social science studies. Our analytic arguments and numerical studies suggest that the methods proposed in this work may be useful in clustered data analyses.  相似文献   

12.
Summary The conditions for obtaining representative, primary adult rat hepatocyte cultures were explored. The methods applied included enzymatic liver perfusion which was nondestructive to hepatocytes, the prevention of aggregation of dissociated cells and the selective attachment of viable cells. These procedures yielded a recovery of 50% of the liver cells which gave rise to cultures representing 14% of the total liver cells. The cultures were composed of homogeneous epithelial-like cells cytologically similar to hepatocytes and possessed a number of liver-specific enzymes. There was virtually no cell division initially and most cells died between 24 and 48 hr. Insulin enhanced the attachment of the liver cells, altered their morphology, but did not prolong cell survival. This study was supported by grant no. BC 133 from the American Cancer Society.  相似文献   

13.
14.
With one step DNA staining methods including cell membrane lysis and RNase treatment, we regularly observed a higher fluorescence emission in liver nuclei compared to bone marrow nuclei in C57BL/6 mice. Therefore this study was conducted in order to emphasize such a phenomenon in other organs and to assess if higher fluorescence emission was related to higher DNA content or staining procedure failure. Liver, bone marrow and testis were removed from Swiss, BDF and C57BL/6 mice. The following samples were prepared: 1) liver cells with TRBC (TRBC = Trout Red Blood Cells = internal standards), 2) bone marrow cells with TRBC, 3) testis cells with TRBC and 4) mixtures of liver, bone marrow and testis cells. The staining procedures were: A) one step pH 10 procedure described by Vindelov (Virchows Arch. B. Cell Path., 1977, 24, 227-242), B) same procedure with twice RNase concentration, C) first method with twice NP 40 concentration and D) three steps procedure including Trypsin and Spermine treatment (Vindelov et al., Cytometry, 1983, 3, 323-327). In protocols A, B and C, "Diploid cells/TRBC" ratio differed significantly between liver, bone marrow and testis nuclei. Moreover, 3 distinct populations of diploid cells were present in samples 4. In protocol D, "Diploid cells/TRBC" ratio were identical between liver, bone marrow and testis nuclei. In samples 4, only 1 population of diploid cells has been observed. This study shows that DNA stabilization by polyamine and protein degradation by protease could act on Propidium Iodide fixation and/or fluorescence emission, with significant differences according to the origin of the cells.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
A single method is described for quantitation of 14 retinoids found in biological material. The method consists of reversed-phase HPLC, internal standardization, and carrier extraction procedures with three synthetic retinoids. Primary standardization of HPLC uv detector is achieved using tritiated all-trans-retinoic acid, all-trans-retinol, all-trans-retinyl palmitate, and all-trans-retinyl acetate. Extraction methods are standardized by correlating the uv absorbance of retinoids at 340 nm with radioactivity of tritiated retinoids of known specific activity. Quantitation of 10 pg of tritiated or 5 ng of nonradioactive retinoid per 0.1 g sample in a polarity range from 4-oxo-retinoic acid to retinyl stearate can be achieved in a single, 50-min chromatographic run. A single HPLC pump, a C18 reversed-phase analytical column, a multistep three-solvent gradient, and inexpensive solvents based on methanol, water, and chloroform comprise this cost-effective chromatographic system. Our primary standardization method allows investigators employing different procedures to compare results between laboratories by standardizing the HPLC uv detector with commercially available tritiated retinoids. With this method we were able to quantitate nanomolar amounts of endogenous retinoic acids and retinyl esters, that "HPLC uv only" conditions usually would not detect in the circulation and liver of rats under physiological conditions.  相似文献   

16.
An improved assay for measuring intercellular adhesive selectivity of embryonic chick liver cells is described. Three major improvements over earlier procedures are noted: (a) enhanced reproducibility of liver cell-liver cell aggregate adhesion (homotypic adhesion) was achieved; (b) 25-70% of the input cells adhered to the collecting aggregates during the course of routine experiments as compared to the 0.25% in earlier assays. This increase in cellular adhesion suggests that the observed cell pick-up is a characteristic of the majority of the dissociated liver cell population; (c) the rate of intercellular adhesion was increased 1,000-fold. The main feature of the assay is that it measures the tissue adhesive selectivities of the dissociated cell population. Studies were undertaken on three embryonic chick tissues (liver, neural retina, and mesencephalon) to determine the tissue selectivity of intercellular adhesion of these dissociated cell types. Some general properties of liver cell homotypic adhesion have been studied and are reported.  相似文献   

17.
Rats were given intravenous injections of l-[1-14C]leucine. Twelve minutes after injection, testes, kidneys, livers, and hepatomas were excised rapidly from one group of animals bearing Morris hepatoma 5123tc. From a second group of rats, the blood was removed 90 min after injection. Tissue extracts and serum were divided into three portions each, and albumin was isolated from each of the three portions by one of three different methods.The three different isolation procedures were the following: (A) pretreatment of the tissue extracts and serum with bovine serum albumin and its specific antiserum and subsequent immunoprecipitation of the rat serum albumin, (B) direct immunoprecipitation followed by dissolving the precipitated rat serum albumin in acid/ethanol, precipitation with ether, and ion-exchange chromatography of the redissolved albumin on CM-cellulose, and (C) a modification of a procedure published previously including fractionation with trichloroacetic acid, ethanol, ether, and ammonium sulfate, chromatography on Sephadex G-100 and DEAE-cellulose, and preparative disc electrophoresis in polyacrylamide gel at pH 10.3 and pH 2.7.With method (A), radiochemically pure albumin can be obtained only from serum. Even though testis and kidney do not synthesize albumin, albumin preparations isolated by this procedure from these organs contain significant amounts of radioactivity. Specific radioactivities measured in albumin prepared by method (A) from the four tissues examined are 5–19 times larger than those in preparations isolated by method (C). Thus, method (A) is inappropriate for the isolation of radiochemically pure albumin from the tissues studied.Procedure (B) is sufficient to obtain radiochemically pure albumin from the serum as well as from the other tissues examined except liver. With liver, this method yields an albumin preparation containing 53% more radioactivity than does albumin isolated with method (C).Method (C) is the only procedure yielding radiochemically pure albumin from all sources, including liver. In liver and hepatoma, the properties of the radioactive impurities are very similar to the properties of albumin itself. Therefore, several purification steps and a careful analysis of the distribution of radioactivity among the albumin fractions after chromatographies and electrophoreses are necessary to separate radioactive impurities from the albumin from homogenates of these two sources.  相似文献   

18.
To evaluate the regulation of adenine nucleotide metabolism in relation to purine enzyme activities in rat liver, human erythrocytes and cultured human skin fibroblasts, rapid and sensitive assays for the purine enzymes, adenosine deaminase (EC 2.5.4.4), adenosine kinase (EC 2.7.1.20), hyposanthine phosphoribosyltransferase (EC 2.4.28), adenine phosphoribosyltransferase (EC 2.4.2.7) and 5'-nucleotidase (EC 3.1.3.5) were standardized for these tissues. Adenosine deaminase was assayed by measuring the formation of product, inosine (plus traces of hypoxanthine), isolated chromatographically with 95% recovery of inosine. The other enzymes were assayed by isolating the labelled product or substrate nucleotides as lanthanum salts. Fibroblast enzymes were assayed using thin-layer chromatographic procedures because the high levels of 5'-nucleotidase present in this tissue interferred with the formation of LaCl3 salts. The lanthanum and the thin-layer chromatographic methods agreed within 10%. Liver cell sap had the highest activities of all purine enzymes except for 5'-nucleotidase and adenosine deaminase which were highest in fibroblasts. Erythrocytes had lowest activities of all except for hypoxanthine phosphoribosyltransferase which was intermediate between the liver and fibroblasts. Erhthrocytes were devoid of 5'-nucleotidase activity. Hepatic adenosine kinase activity was thought to control the rate of loss of adenine nucleotides in the tissue. Erythrocytes had excellent purine salvage capacity, but due to the relatively low activity of adenosine deaminase, deamination might be rate limiting in the formation of guanine nucleotides. Fibroblasts, with high levels of 5'-nucleotidase, have the potential to catabolize adenine nucleotides beyond the control od adenosine kinase. The purine salvage capacity in the three tissues was erythrocyte greater than liver greater than fibroblasts. Based on purine enzyme activities, erythrocytes offer a unique system to study adenine salvage; fibroblasts to study adenine degradation; and liver to study both salvage and degradation.  相似文献   

19.
叶云飞  杨倞  孙永健  徐胜  孟岩  刘思博 《生物磁学》2013,(25):4947-4949
目的:探讨和分析三维适形放疗和逆向调强放疗在巨块型肝癌的治疗上的临床价值。方法:回顾性分析了本院自2004年1月至2010年12月间收治的190例巨块型肝癌放射治疗患者的临床资料,根据治疗方式的不同分为三维适形放射治疗(Three—di-mensionalconformalradiationtherapy,3D.CRT)组95例以及逆向调强放疗组(Intensity-modulatedradiotherapy,IMRT)95例。并对放疗后患者肿瘤的直径以及1、3年内的生存率进行对比分析。结果:两种治疗方式对巨块型肝癌具有一定的治疗效果,其中常规三维适形放射治疗能够让肿瘤缩小5-10%,1年和3年后的存活率为78.9%(75/95)、12.6%(12/95);而逆向调强放疗能够让肿瘤缩小15%以上,1年和3年后的存活率为85.3%(81/95)、16.8%(16/95)。结论:三维适形放射和逆向调强放疗技术均可有效的缩小肿瘤,提高患者的1、3年生存率,而逆向调强放疗更具临床优势。  相似文献   

20.
A simplified procedure is presented for the simultaneous purification of the enzymes cytochrome P-450, epoxide hydratase (EC 3.3.2.3), and NADPH-cytochrome P-450 reductase (EC 1.6.2.4) from a single preparation of rat liver microsomes. All three enzymes can be recovered after chromatography of detergent-solubilized microsomes on a column of n-octylamino-Sepharose 4B. The major form of cytochrome P-450 (of phenobarbitaltreated rats) is purified by subsequent DEAE-cellulose chromatography, epoxide hydratase is purified by DEAE- and O-(carboxymethyl)-cellulose chromatography, and NADPH-cyto-chrome P-450 reductase is purified using 2′,5′-ADP agarose chromatography. The nonionic detergent Lubrol PX and the ionic detergents sodium cholate and deoxycholate are used in these procedures to permit utilization of uv-absorbance measurements in monitoring protein during purification. Overall yields of the three enzymes are approximately 20, 25, and 60%, respectively. All three enzymes are apparently homogeneous as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and are functionally active. The same procedure can be used to obtain the major cytochrome P-450 present in liver microsomes isolated from β-naphthoflavone (5,6-benzoflavone)- or 3-methylcholanthrene-treated rats. Thus, the described procedures permit the rapid and reproducible purification of three major rat liver microsomal enzymes which can be coupled to study bioactivation and detoxification of a variety of xenobiotics in reconstituted systems.  相似文献   

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