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1.
During the course of our studies on the chemical constituents of botanically identified Chinese licorice roots of various origins, we have identified 15 kinds of saponins and 49 kinds of flavonoids (including flavonoid glycosides). With these chemical constituents at hand, we have carried out the chemical evaluation studies of licorice roots available in Japan by means of high performance liquid chromatography (HPLC). In the HPLC analysis using an ODS reversed-phase column, a combination of 1% aqueous acetic acid and acetonitrile was used as the mobile phase in a gradient solvent system, and the eluate was monitored with UV absorption at 254 nm (for saponins with a diene or a conjugated carbonyl moiety, liquiritin, and liquiritin apioside) or at 350 nm (for other flavonoid constituents). By our analytical method described here, quantitative analyses of saponin and flavonoid constituents were effected simultaneously. We have found an interesting piece of information concerning the origin of parent plants and their characteristic constituents such as saponins and flavonoids.  相似文献   

2.
Isolates of Serratia have been isolated from the rhizosphere of oilseed rape. The percentage of Serratia in this microenvironment was determined as 12.4% of the total antifungal bacteria. Serratia liquefaciens, S. plymuthica and S. rubidaea were found. All of the isolates showed an antifungal activity against different phytopathogenic fungi in vitro but the efficiency of strains was different. The antifungal mechanisms of 18 selected strains were investigated. Direct antifungal effect may be based on antibiosis (production of prodigiosin and pyrrolnitrin) and production of lytic enzymes (chitinases and beta-1,3-glucanases). Potent siderophores were secreted by the strains to improve the availability of iron. No strain was able to produce cyanide. Most of the strains secrete the plant growth hormone indole-acetic-acid which can directly promote the growth of roots. The mechanisms were specific for each isolate.  相似文献   

3.
BACKGROUND: Hepatocyte growth factor/scatter factor (HGF/SF) is a potent mitogen for various neoplastic cells, including neoplastic bronchial epithelia. METHODS: Immunoreactive hepatocyte growth factor/scatter factor (HGF/SF) was measured in extracts prepared from 129 nonsmall cell lung carcinoma (NSCLC) specimens, using an enzyme-linked immunosorbent assay. These specimens represented 5 cases of solitary/localized bronchioloalveolar cell carcinoma (BAC), 4 cases of diffuse/infiltrative BAC, 90 cases of non-BAC adenocarcinoma, 25 cases of squamous cell carcinoma, and 5 cases of large cell carcinoma. RESULTS: The mean concentration of immunoreactive HGF/SF was more than 19-fold higher in tissue extracts from diffuse-type BAG (265.0 +/- 110.2 ng/100 mg protein) than in those from solitary-type BAC (13.9 +/- 15.9, P < 0.005), non-BAC adenocarcinoma (13.8 +/- 14.9, P < 0.001), squamous cell carcinoma (13.2 +/- 14.4, P < 0.001), or large cell carcinoma (11.2 +/- 6.5, P < 0.005). When immunohistochemical staining for HGF/SF was performed, intense HGF/SF staining was uniformly observed in diffuse-type BAC tumor cells, but not in solitary-type BAC. CONCLUSIONS: Although BAC is included as a subtype of adenocarcinoma in the World Health Organization classification, diffuse-type BAC should be considered a distinct biologic entity, at least in terms of HGF/SF expression, from solitary-type BAC or non-BAC adenocarcinoma. In addition, the solitary and diffuse forms of BAC are known to be associated with different prognoses; for the latter, the prognosis is much poorer than for the former. The results of this study may at least partly explain this difference in prognosis.  相似文献   

4.
Sixteen patients with hypogonadotropic hypogonadism received gonadotropin replacement therapy. Two patients treated with HCG alone showed induction of spermatogenesis 2 and 12 months after the start of treatment. Three subjects receiving combination therapy showed sperm appearance 6-28 months after treatment. The patients showing sperm appearance, whose testicular volume was > or = 4 ml, showed a higher sperm count and impregnated their partners, although no relationship was found between pretreatment testicular volume and sperm appearance. The response to HCG test correlated with sperm appearance after gonadotropin therapy. Sperm appearance was not observed in any subject except for one who showed no response to luteinizing hormone-releasing hormone (LH-RH) test and none of the patients without response of FSH to LH-RH demonstrated any induction of spermatogenesis. In conclusion, the responses to LH-RH test and possibly to HCG test could predict the induction of spermatogenesis after gonadotropin replacement therapy, and a large testicular volume is associated with post-treatment fertility.  相似文献   

5.
A rapid and reliable method using microwave energy is described for the extraction of spiked and incurred (freeze-dried and fresh) sulphamethazine residues from swine tissues/organs (muscle, liver and kidney). Incurred tissues were obtained from an abattoir and freeze-dried pig tissue reference materials were produced as part of a reference material study for the Community Bureau of References, European Communities. The extraction was achieved by irradiating the sample in methanol for 25 s in a household microwave oven, commonly referred to as microwave-assisted extraction (MAE). The extracts were analysed without clean-up by high performance liquid chromatography (HPLC) using a C18 column and detected at 450 nm after derivatization with 4-dimethylaminobenzaldehyde (DMABA) in a heated rector at 40 degrees C. The limit of quantitation was 2.5 micrograms kg-1 of wet tissues. A comparison of MAE with an homogenization technique indicated that MAE worked extremely well for freeze-dried samples, while it showed significant variation for wet tissues. No sulphamethazine was detected in retail pork meat and liver samples when analysed by the MAE technique.  相似文献   

6.
While functional magnetic resonance imaging (fMRI) is now used widely for demonstrating neural activity-related signals associated with perceptual, motor, and cognitive processes in humans, to date this technique has not been developed for use with nonhuman primates. fMRI in monkeys offers a potentially valuable experimental approach for investigating brain function, which will complement and aid existing techniques such as electrophysiology and the behavioral analysis of the effects of brain lesions. There are, however, a number of significant technical challenges involved in using fMRI with monkeys. Here, we describe the procedures by which we have overcome these challenges to carry out successful fMRI experiments in an alert monkey, and we present the first evidence of activity-related fMRI signals from monkey cerebral cortex.  相似文献   

7.
SPME/semi-microcolumn HPLC (SPME/LC) was investigated to analyze benzodiazepines in human urine samples. SPME conditions such as extraction time, extraction temperature, salt concentration and pH of matrix, flush volume and desorption time were optimized by extracting various drugs from a prepared water matrix. Combination of adding saturated salts to the matrix and controlling pH ranged from neutral to weakly alkaline conditions makes the increase of extraction efficiency. Under optimal condition SPME/LC is more sensitive than direct HPLC analysis without the SPME process. The limits of detection (LODs) was several ppb level and the relative standard deviation (RSD) was < 15% when human urine samples were analyzed by this analytical system. The system is very useful and is enough to assay benzodiazepines in a human urine sample without tedious and complex analytical procedures. In this paper the applicability of SPME/LC to the analysis of benzodiazepines in human urine samples was reported. In addition, the extension to the evaluation of SPME/LC/MS system was also described.  相似文献   

8.
A knowledge-based system (KBS) is discussed for the dynamic simulation and fault diagnosis of various metallurgical reactor systems. The fundamental basis (deep knowledge) of the model is a data base containing concentration-time data and an accompanying generalized kinetic model. The knowledge base is defined by various facts, objects, rules, and functions, which capture both deep as well as shallow knowledge regarding the process. This approach permits the simulation and fault diagnosis or identification of metallurgical reactors at all reactor conditions catered to by the knowledge base. Various examples, which include adsorption, leaching, and reduction (pyrometallurgical) reactions, illustrate the various facets of the proposed knowledgebased simulation (batch and continuous), process identification, and knowledge representation. formerly Senior Lecturer, University of Stellenbosch  相似文献   

9.
High-performance liquid chromatography with evaporative light scattering detection (HPLC-ELSD) and thin layer chromatography with flame ionization detection (TLC-FID) have been applied to the separation of five main free bile acids present in humans: cholic (CA), chenodeoxycholic (CDCA), deoxycholic (DCA), lithocholic (LCA) and ursodeoxycholic (UDCA) acid. HPLC separation was performed on Biospher Si 100 column using a mixture of n-heptane, isopropanol, ethylacetate, methanol and glacial acetic acid as a mobile phase. All the compounds were separated in less than 12 minutes by using a gradient elution mode. TLC-FID separation was performed on S-II Chromarods with a mixture of isooctane, ethylacetate and glacial acetic acid as a mobile phase. HPLC-ELSD method was applied to the determination of CDCA and UDCA in pharmaceuticals and their purity control when LCA, DCA and CA were considered as impurities.  相似文献   

10.
Two specific methods for the simultaneous determination of nimesulide, a non steroidal anti-inflammatory drug, and its hydroxylated metabolite in human plasma are described. Adopting a high performance liquid chromatographic (HPLC) system with UV detection (230 nm), the compounds, extracted from plasma in acidic medium, were separated on ODS columns under gradient conditions, using a phosphate buffer solution and methanol as mobile phase. For each method column length, gradient rate and composition were appropriately selected. The limit of quantitation was 25 ng/mL for both compounds. The two methods were validated by intra day assays at three concentration levels and applied in kinetic studies in healthy volunteers, during which inter-day assays were carried out confirming their feasibility.  相似文献   

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12.
PURPOSE: An immortalized human corneal epithelial cell line (HCE) was tested as a screening tool for prediction of topical ocular irritation/toxicity by pharmaceuticals METHODS: Effects of various drugs, excipients and cyclodextrins (CDs) on viability of HCE cells were evaluated using two in vitro cytotoxicity tests, 3-(4,5-dimethlthiazol-2-yl)-205-diphenyl tetrazolium bromide (MTT) dye reduction assay and propidium iodide assay. RESULTS: Mitochondrion-based MTT test was a more sensitive indicator of cytotoxicity than the plasma membrane-based propidium iodide test. The tests revealed following cytotoxic rankings for ophthalmic drugs: dipivefrin > timolol > pilocarpine approximately equal to dexamethasone; for excipients: benzalkonium chloride (BAC) > sodium edetate (NA2 EDTA)>polyvinyl alcohol (PVA) > methylparaben; and for CDs :alpha- CD > dimethyl beta-cyclodextrin (DM-beta-CD) > sulfobutyl ether beta-cyclodextrin ((SBE)7m-beta-CD approximately equal to hydroxypropyl-beta-cyclodextrin (HP-beta-CD) > lambda CD. In consideration of the in vivo clinical situation, the short exposure time (5 min) is more relevant even though toxic effects of some test substances were seen only after longer exposure time (30 and 60 min). CONCLUSIONS: Immortalized HCE cells are a promising tool for rapid cytotoxicity assays of ocular medications. The cell line is potentially useful in predicting the in vivo coreal toxicity of ocularly applied compounds.  相似文献   

13.
We have made an immunohistochemical study of the vomeronasal (VN) complex of 12-day-old rats to characterize the innervation of its blood vessels. The VN complex can be subdivided into rostral, middle and caudal segments, each one with a particular vascularization pattern. Several small vessels were associated with the rostral segment, whereas a large venous sinus ran along the middle and caudal segments. Immunostaining for alpha-smooth muscle actin demonstrated that the muscular sheath was asymmetric, with more cells layers in its lateral than in its medial walls. Nerves were demonstrated with antisera against protein gene product 9.5 (PGP), and against several molecules associated with specific classes of nerve fibers: the C-terminal peptide of neuropeptide Y (CPON), calcitonin gene-related peptide (CGRP), substance P (SP), galanin (GAL), vasoactive intestinal peptide (VIP) and neuronal nitric oxide synthase (NOS). The latter, was also studied with NADPH-diaphorase. Vascular associated fibers exhibited NOS-, CPON-, GAL-, CGRP-, SP- and VIP-immunoreactivity. Only the vessels of the rostral segment showed VIP-immunoreactive fibers. Each wall of the venous sinus exhibited different types of nerve fibers. CPON-, GAL-, CGRP- and SP-immunoreactive fibers concentrated in the medial wall, whereas NOS-immunoreactive ones concentrated in the lateral wall. This distribution of vascular fibers, plus the presence of sensory fibers exhibiting CGRP-, SP- and GAL-immunoreactivity within the pseudostratified epithelium of the VN tube, would be relevant to understand the operation of the pumping mechanism regulating influx and efflux from the VN tube.  相似文献   

14.
AIM OF STUDY: Intrathecal sufentanil has recently been used in labour as part of a combined spinal epidural technique. This study was conducted to compare its use in combination with bupivacaine for caesarean section with fentanyl added to bupivacaine and bupivacaine alone. METHODS: Sixty ASA I and II patients for non-emergency caesarean section under spinal anaesthesia were divided into three groups to receive 15 micrograms fentanyl added to 7.5 mg bupivacaine, 10 micrograms sufentanil added to 7.5 mg bupivacaine and 7.5 mg bupivacaine. Onset time of sensory blockade, side effects, surgical conditions, neonatal outcome and quality of the anaesthetic was assessed. On the first postoperative day, duration of effective analgesia, side effects and patient satisfaction were noted. RESULTS: The duration of effective analgesia of bupivacaine alone was prolonged with the addition of sufentanil and fentanyl by 358% and 256% respectively. No patient in the sufentanil and fentanyl groups required additional intra-operative analgesics compared with 17.6% of patients in the bupivacaine alone group. There was an increase in incidence of desaturation in the sufentanil group (45%) and fentanyl group (5.6%) compared with the bupivacaine only group (0%). The incidence of pruritus was 35% with sufentanil, 27.8% with fentanyl against 0% with bupivacaine alone. CONCLUSION: The addition of 10 micrograms of sufentanil and 15 micrograms of fentanyl to 7.5 mg of bupivacaine prolonged the duration of effective analgesia and improved intra-operative analgesia. However, the incidence of pruritus and episodes of desaturation were increased more with 10 micrograms sufentanil than with 15 micrograms fentanyl.  相似文献   

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16.
Familial growth hormone deficiency type 1A is an autosomal recessive disease, caused by various homogenous deletions of both alleles of growth hormone gene 1 (hGH1). The hGH1 gene deletion is an event occurring between the 5' and the 3' flanking regions by unequal recombination, which causes a deletion in the hGH1 gene, mostly of 6.7 kb and rarely 7.6 or 7.0 kb in size. Two brothers diagnosed with GH deficiency syndrome were sent to our hospital for further evaluation. DNA samples of the probands and controls were amplified by PCR; restriction endonuclease analysis was done with Sma I enzyme and the patterns were evaluated. Gel electrophoresis results showed that the two brothers had a 7.0 kb deletion. These are the third and fourth cases reported with a 7.0 kb deletion. Both patients responded well to replacement therapy and did not develop antibodies against rGH. No other relatives presented with macro deletions in the hGH1 gene.  相似文献   

17.
煤中天然有机物的高效液相色谱-质谱/质谱分析   总被引:2,自引:0,他引:2       下载免费PDF全文
运用红外光谱法测定褐煤氧化前后的结构变化,在1580cm-1及1400cm-1处的两个特征峰表明氧化煤中含有大量的羧酸类物质。以此为基础,采用温和的碱氧化方法对煤进行氧化处理,选择了合适的分离条件,建立了氧化煤中天然有机物质预分离样品的高效液相色谱方法,并通过电喷雾串联质谱(ESI(-)-MS/MS)法对其中一组质量数相差58的物质进行了细致的分析。选择m/z268为特征吸收峰,并依据煤的大分子结构,对分析得到的物质进行细致的结构推测,认为该物质应为含有两个乙酸基侧链的炔基喹啉,其化学式为C15H11NO  相似文献   

18.
高效液相色谱法测定电镀用氰化亚金钾中的杂质元素   总被引:1,自引:1,他引:1  
台希  杨艳  朱利亚  黄齐林  胡秋芬 《黄金》2007,28(5):43-46
研究了用高效液相色谱法测定电镀用氰化亚金钾中的杂质元素.电镀用氰化亚金钾样品用微波消解,然后用甲基异丁基酮(MIBK)萃取分离金.镍、铜、铁、铅、镉、汞6种杂质元素用四-(对二甲氨基苯基)-卟啉 (T4-DMAPP) 柱前衍生,然后用甲醇和四氢呋喃为流动相,ZORBAX Stable Bound (4.6mm×50mm,1.8μm)快速分离柱为固定相分离,6种杂质元素的配合物在 2.0min内可达到分离;用二极管矩阵检测器检测,镍、铜、铁、铅、镉、汞的检测限分别为:40ng/L、30ng/L、50ng/L、40ng/L、20 ng/L和40ng/L.该方法相对标准偏差为1.8%~3.4%,标准加入回收率为92%~106%.该方法用于测定电镀用氰化亚金钾样品中的痕量镍、铜、铁、铅、镉、汞,结果令人满意.  相似文献   

19.
The present study describes the determination of two different types of hepatotoxic pyrrolizidine alkaloids (PAs) and also distinguishing the hepatotoxic PAs from non-toxic ones by both in-source collision-induced dissociation high performance liquid chromatography mass spectrometry (CID-HPLC/MS) and HPLC/MS/MS (CID in the collision cell), using electrospray ionization. The mass spectra provided molecular ions and characteristic fragment ions, which could be used readily for a rapid identification of different types of PAs. Applications of both in-source CID-HPLC/MS and HPLC/MS/MS analytical methods were successful for the determination of PAs in blood samples obtained from rats dosed with PAs and in the PA-containing plant. The results demonstrated that the developed HPLC/MS methods with two different CID techniques provided a very simple and rapid analysis for an unequivocal diagnosis of PA poisoning and for definitive identification of PAs in plants or herbal medicines.  相似文献   

20.
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