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81.
New research has indicated that Gastrodiae Rhizome (GR) has potential anti‐diabetic and anti‐asthmatic effects in mouse models. On the basis of our previous study of the relative bioavailability of gastrodin (GAS) and parishin (PA) from extract and powder of GR, we performed further research on the tissue distribution and excretion of the two analytes. A reliable bioanalytical method for the quantification of GAS and PA in rat tissues and excretion is required. Chromatographic separation was carried out on a gradient mobile phase of acetonitrile–water with 0.1% formic acid. Calibration curves (1/x 2 weighted) offered satisfactory linearity (r 2 > 0.9835) within 100–3000 ng mL−1 for GAS and (r 2 > 0.9862) within 10–1000 ng mL−1 for PA. The relative standard deviations of the intra‐day and inter‐day precision were all <14.98%, whilst the relative errors of the intra‐day and inter‐day accuracy were all within ±14.71%. The matrix effect and recovery values were satisfactory in all of the biological matrices examination. The data of relative differences in tissue distribution and excretion of GAS and PA from powder and extract of GR indicated that higher bioavailabilities for GAS and PA were obtained when a dosage of 4 g kg−1 GR powder was used.  相似文献   
82.
Rhizoma Alismatis (RA), a diuretic in Asia and Europe, was found to possess anti‐hyperlipidemic activity. Since the biomarkers and mechanisms of RA in the treatment of hyperlipidemia are inadequate, ultra‐performance liquid chromatography coupled with quadrupole time‐of‐flight synapt high‐definition mass spectrometry and multivariate data analysis were employed to investigate the urinary metabolomics of RA on hyperlipidemic rats induced by high‐fat diet. The metabolic profile of RA‐treated hyperlipidemic group located between control and diet‐induced hyperlipidemic groups. Nineteen metabolites with significant fluctuations were identified as potential biomarkers related to the hyperlipidemia and anti‐hyperlipidemia of RA using partial least‐squares‐discriminate analysis, heatmap analysis and correlation coefficient analysis. The fluctuations of these biomarkers represented disturbances in amino acid metabolism, purine metabolism, pyrimidine metabolism and energy metabolism. After RA treatment, these perturbed metabolites were restored to normal or nearly normal levels. RA can alleviate high‐fat diet‐induced dysfunctions in these metabolic pathways.  相似文献   
83.
The growth of mass spectrometry (MS) in clinical chemistry has primarily occurred in two areas: the traditional clinical chemistry areas of toxicology and therapeutic drug monitoring and more recent, human genetics and metabolism, specifically inherited disorders of intermediary metabolism and newborn screening. Capillary gas chromatography and electrospray tandem MS are the two most common applications used to detect metabolic disease in screening, diagnostics and disease monitoring of treated patients. A few drops of blood from several million newborn infants are screened annually throughout the world making this the largest application of MS in medicine. Understanding the technique, how it grew from a few dozen samples per week in the early 1990s to increasing daily volume today will provide important information for new tests that either expand newborn screening or screening in other areas of metabolism and endocrinology. There are numerous challenges to the further expansion of MS in clinical chemistry but also many new opportunities in closely related applications. The model of newborn screening and MS in medicine may be useful in developing other applications that go beyond newborns and inherited metabolic disease. As MS continues to expand in clinical chemistry, it is clear that two features will drive its success. These features are excellent selectivity and multiple analyte or profile analysis; features recognized in the 1950s and remain true today. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
84.
Photoacoustic spectroscopy (PAS) is a recently developed, non‐destructive testing (NDT) tool, used for analyzing the physical properties of materials. This method is used here to determine the thermal diffusivity and conductivity of the gel‐grown single crystals of hippuric acid, a minor constituent of urinary calculi and also a non‐linear optical (NLO) material. Optical absorption of the specimen was studied using its PA spectrum and compared with UV‐visible absorption spectra. Second harmonic generation (SHG) conversion efficiency was also carried out. Characterization of the crystals was made using X‐ray powder diffraction and density determination. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
85.
高效液相色谱法测定小鼠尿中的盐酸戊乙奎醚S型异构体   总被引:1,自引:0,他引:1  
薛明  阮金秀  袁淑兰  张振清  吴波  李宇航 《色谱》2003,21(2):151-153
建立了测定动物体液中S型盐酸戊乙奎醚异构体的高效液相色谱法,研究了S型异构体在小鼠体内的排泄。以Spherisorb SiO2色谱柱(150 mm×4.6 mm i.d.,5 μm)分离S型异构体,外标法定量。S型盐酸戊乙奎醚异构体的线性范围为0.5-100.0 mg/L, 最低检测质量浓度为0.1 mg/L。肌注给药后不同时间内,S型异构体在小鼠尿中的比值(S-1/S-2)存在显著性差异。48 h内各异构体在尿中的排泄量明显不同,说明S型异构体在小鼠体内可能呈现立体选择性排泄。此法简便、经济,可用于动物  相似文献   
86.
粘液素对草酸钙晶体生长的影响   总被引:2,自引:0,他引:2  
泌尿系结石是一种常见疾病。在70%以上的结石中,草酸钙(CaOxa)单独或和其它钙盐共同为主要成分。一般认为正常人不形成尿石是其尿液中存在的抑制剂抑制了CaOxa晶体的成核、生长、聚集或固相转化。  相似文献   
87.
《Analytical letters》2012,45(3):225-233
Abstract

The presence of disulfated disaccharides containing iduronic acid has been demonstrated in the urine of a Hunter patient by gel filtration of the low molecular weight urinary mucopolysaccharides. Intravenous infusion of a purified fraction from normal human serum causes disappearance of these metabolites which probably represent the substrate of the enzyme deficient in the disease, a sulfatase specific for an ester group situated on position 2 or 3 of the iduronic acid residues of dermatan sulfate.  相似文献   
88.
《Analytical letters》2012,45(10):743-750
Abstract

A method for the detection of α-methyldopa in urine of individuals taking the drug at its therapeutic dose was developed. This test would be useful to ascertain patient compliance and to detect surreptitious use of the drug. The method is effective for detecting α-methyldopa in urine also known to contain azulfidine and/or other antihypertensive agents. No false positive or false negative analysis were obtained to date.  相似文献   
89.
研究了朱砂中汞的生物可接受性及其在体内的吸收与排泄.采用体外消化透析法测定了朱砂中汞的生物可接受性;计算了大鼠灌胃给予临床剂量(50mg/kg)朱砂后汞的药动学参数;测定了给予临床剂量的朱砂后大鼠粪样中汞的排泄量.结果表明,朱砂中汞的溶出率为0.011%,生物可接受率为0.003 3%.大鼠灌胃给予临床剂量的朱砂后,汞的药动学参数为:最高血药浓度(ρmax)为(6.3±1.3)μg/L,达峰时间(tmax)为(1.3±0.4)h,半衰期(t1/2)为(4.2±0.5)h,血药浓度-时间曲线下面积(AUC)为(54.7±8.7)μg.h.L-1.给予朱砂12h后汞在粪便中排泄量最大,96h后在粪样中仍可检测到少量汞.朱砂中汞的生物可接受性较低,在体内吸收少,滞留时间较长,排泄缓慢,长期服用可在体内蓄积,产生毒性.  相似文献   
90.
Urolithiasis, the category of diseases associated with the formation of kidney stones, has many causes. However, only a few have been documented as aggravating calculi depositions and aggregations. This amply justifies continued work in developing effective and efficient inhibition and treatment techniques. The recent resurgence in reviews on plant antiurolithiatic activity has given credence to the application of modern spectroscopic analysis, and has led us to this study. Results obtained from Raman and infrared (IR) absorption analysis of inhibited calculi growth resulting from laboratory synthesis of calcium oxalate crystals accompanied by the natural infusion of Larrea tridentata are reported. A visible decrease in calcium oxalate crystal growth with increasing amounts of L. tridentata herbal infusion was observed in photomicrographs, as well as a color change from white‐transparent for pure crystals to light orange‐brown for crystals with inhibitor. Both Raman and IR absorption spectra reveal a monohydrate structure for the crystals grown alone, which transform to a dihydrate morphology with the addition of the L. tridentata inhibitor. Furthermore, the resulting data support the possibilities of the influences, in this complex process, of the nordihydroguaiaretic acid (NDGA) and its derivative compounds from L. tridentata and the bonding of the magnesium of the inhibitor with the oxalate ion on the surface of the calculi crystals. This assumption corroborates well with the micrographs obtained under higher magnification, which show that the separated small crystallites consist of a darker brownish core, which we attribute to the dominance of growth inhibition by NDGA, surrounded by light transparent thin shells, which possibly correspond to passivation of the crystals by magnesium oxalate. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
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