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951.
应用高速逆流色谱法(HSCCC)分离纯化了高良姜中3种二苯基庚烷类化合物。以正己烷-乙酸乙酯-甲醇-水(2:3:1.75:1, v/v/v/v)为两相溶剂系统,下相为固定相,上相为流动相,在主机转速为858 r/min、流速1.5 mL/min的条件下,从122.20 mg高良姜石油醚萃取物中经一步HSCCC分离可制备得到5R-羟基-7-(4-羟基-3-甲氧基苯基)-1-苯基-3-庚酮(7.37 mg)、7-(4-羟基-3-甲氧基苯基)-1-苯基-4E-烯-3-庚酮(9.11 mg)和1,7-二苯基-4E-烯-3-庚酮(15.44 mg),经高效液相色谱分析,纯度均大于93%,各化合物的结构由质谱和核磁共振氢谱、碳谱鉴定确证。该方法简便、快速、高效,可用于高良姜中二苯基庚烷类化合物的快速分离制备。 相似文献
952.
In this paper, a genetic algorithm‐support vector regression (GA‐SVR) coupled approach was proposed for investigating the relationship between fingerprints and properties of herbal medicines. GA was used to select variables so as to improve the predictive ability of the models. Two other widely used approaches, Random Forests (RF) and partial least squares regression (PLSR) combined with GA (namely GA‐RF and GA‐PLSR, respectively), were also employed and compared with the GA‐SVR method. The models were evaluated in terms of the correlation coefficient between the measured and predicted values (Rp), root mean square error of prediction, and root mean square error of leave‐one‐out cross‐validation. The performance has been tested on a simulated system, a chromatographic data set, and a near‐infrared spectroscopic data set. The obtained results indicate that the GA‐SVR model provides a more accurate answer, with higher Rp and lower root mean square error. The proposed method is suitable for the quantitative analysis and quality control of herbal medicines. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
953.
ABSTRACTSurface-enhanced Raman scattering spectroscopy was employed to analyze the biochemical composition of the Saposhnikovia divaricata decoction, which is a common traditional Chinese medicine. No reliable Raman peak was observed in traditional Raman spectra of Saposhnikovia divaricata decoction. However, 12 main Raman peaks (534, 616, 648, 685, 730, 781, 850, 958, 1242, 1319, 1460, and 1571 cm?1) were observed in the surface-enhanced Raman scattering spectroscopy spectra from the mixture of silver colloids with Saposhnikovia divaricata decoction as a result of the silver colloid enhanced effects on the Raman scattering of Saposhnikovia divaricata decoction. The results demonstrated that the surface-enhanced Raman scattering spectroscopy may provide a new kind of non-destructive, accurate, direct, and fast detecting method for the Saposhnikovia divaricata decoction or other traditional Chinese medicine in the form of decoction. 相似文献
954.
Klaus D. Wutzke Michael Tisztl Birgit Salewski Änne Glass 《Isotopes in environmental and health studies》2013,49(4):488-496
Three resistant starches (RSs), namely fibre of potatoes (FP), wrinkle pea starch (WPS), and high amylose maize starch (HAMS) with different dietary fibre contents, were supplemented in adults to evaluate their effects on urinary nitrogen and ammonia excretion as well as on faecal nitrogen excretion by means of lactose-[15N2]ureide (15N-LU) degradation. Twenty subjects received a regular diet either without or with the supplementation of FP, WPS, and HAMS in a randomized order. After administration of 15N-LU, urine and faeces were collected over 48 and 72 h, respectively, whereas blood was collected after 6 h. The 15N-abundances were measured by isotope ratio mass spectrometry. In comparison to the dry run, supplementation with RS significantly lowered renal 15N-excretion (dry run: 43.2?%, FP: 34.6?%, WPS: 37.9?%, HAMS: 36.4?%) as well as the corresponding 15NH3-excretion (dry run: 0.08?%, FP: 0.06?%, HAMS: 0.05?%), clearly indicating a reduced colonic nitrogen generation at high dietary fibre intake. 相似文献
955.
Paul Afolabi Mark Wright Steve A. Wootton Alan A. Jackson 《Isotopes in environmental and health studies》2013,49(3):346-356
This study determined the rates of 13C-aminopyrine metabolism in patients with varying degrees of liver cirrhosis as defined by clinical scores. Twenty-five cirrhotic patients and 18 healthy subjects underwent a 13C-aminopyrine breath test. The cumulative per cent dose recovery (cPDR) of 13C on breath expressed as a percentage of the administered dose at 2 h was significantly lower in cirrhotic patients than in healthy subjects (median: 1.7% versus 9.0%; p<.0001). Significant inverse associations between cPDR at 2 h and the model for end-stage liver disease score, Child–Pugh score, international normalised ratio and bilirubin (all p<.05), but not alanine aminotransferase or alkaline phosphatase were observed in the cirrhotic patients. Taking each biochemical marker independently, cirrhotic patients with normal biochemistry had a significantly lower cPDR at 2 h than healthy subjects (all p<.05). Differences in 13C-aminopyrine metabolism were evident in cirrhotic patients with less severe disease and may mark hepatic dysfunction when conventional biochemical markers appear unchanged. 相似文献
956.
Resistant starch (RS) and Lactobacillus acidophilus yoghurt (LC1) were supplemented simultaneously in healthy adults to evaluate the effect on the urinary and faecal nitrogen and ammonia excretion by means of lactose-[15N2]ureide (15N-LU) degradation. Nineteen subjects received a regular daily diet either without or with supplementation of an RS-LC1-mixture composed of fibre of potatoes (RS type 1), wrinkle pea starch (RS type 2), and LC1 over a 20-day period in randomised order. Thereafter, 15N-LU was administered together with breakfast. Urine and faeces were collected over a period of 48 and 72 h, respectively. The 15N abundances were measured by isotope ratio mass spectrometry. The intake of the pre- and probiotic mixture composed of RS of type 1, type 2 and of LC1 significantly lowered the colonic generation and the renal excretion of toxic 15NH3 and functioned as an ammonia shift from urinary to faecal 15N excretion when using 15N-LU as a xenobiotic marker. 相似文献
957.
Am 8. und 9. November des vergangenen Jahres fand in Magdeburg das I. Strahlenschutzkolloquium für Kontakttherapie in der Medizin statt. Veranstalter war die Staatliche Zentrale für Strahlenschutz. Als ein wichtiges Ergebnis dieser Tagung kann die seit langem angestrebte Einigung über die vom Hersteller (Institut für angewandte Isotopenforschung, Berlin-Buch) vorgeschlagenen Konstruktionsparameter gynäkologischer 60Cound 137Cs-Applikatoren angesehen werden, die in einer vom Vorsitzenden der Problemkommission ?Radiologie” (Prof. Reicliel) einberufenen Sondersitzung unter Teilnahme von 30 Klinikern, Strahlenphysikern und Vertretern des Instituts für angewandte Isotopenforschung erzielt wurde. 相似文献
958.
W. Stolz 《Isotopes in environmental and health studies》2013,49(9):366-369
Für die Messung hoher Dosen in intensiven γ- und Elektronenstrahlungsfeldern, wie sie zur Strahlensterilisierung, Strahlenpasteurilisierung und zur Vergütung von Kunststoffen eingesetzt werden, ist die Entfärbung verschiedenfarbiger kommerzieller Zellglasfolien geeignet. Der Dosismeβbereich reicht von etwa 1 bis 100 Mrad. Bis zu 1000 h nach der Bestrahlung wurden bei einer Lagerung bei 20 und 50°C keine Nachreaktionen beobachtet. Eine Dosisleistungs- und Energieabhängigkeit wurde nicht gefunden. Durch Auf-einanderlegen von 200 Zellglasfolien wurde die Tiefendosisverteilung für 1,5-MeV-Elektronen in Zellglas gemessen. Eine Beziehung zwischen der Extinktion bestrahlter Zellglasfolien und der Energiedosis wird diskutiert. 相似文献
959.
Klaus D. Wutzke 《Isotopes in environmental and health studies》2013,49(2):239-258
Our research group of the Children's Hospital of the University of Rostock (Rostock group) has long-time experience in 15N-labelling and in using yeast protein and its hydrolysates for tracer kinetic studies to evaluate parameters of the whole-body protein metabolism in premature infants. The particular advantage of applying an economically convenient, highly 15N-enriched, and completely labelled yeast protein for evaluating protein turnover rates is the fact that the 15N dose is spread among all proteinogenic amino acids. The absorption has been improved by hydrolysing [15N]yeast protein with thermitase into a mixture of amino acids, dipeptides and tripeptides so that faecal analysis becomes unnecessary when determining turnover rates. The review shows that, in contrast to the application of single 15N-labelled amino acids with resulting overestimation of protein turnover rates, the 15N-labelled yeast protein thermitase hydrolysate represents the amino acid metabolism more closely without causing amino acid imbalances. The 15N-labelled yeast protein thermitase hydrolysate leads to the estimation of reliable protein turnover rates, particularly in premature infants. 相似文献
960.
Increasing evidence has demonstrated that multidrug combinations could amplify the therapeutic efficacies of each agent. Interestingly, the pharmacological effect of traditional Chinese medicine (TCM) is usually attributed to the drug‐interaction property (synergism) of multiple active constituents. Pharmacokinetics is a useful means of evaluating the drug interactions of major active compounds in TCM. A simple, sensitive and reliable RP‐HPLC‐DAD method has been developed to simultaneously quantify 6,7‐dimethylesculetin (D), geniposide (G) and rhein (R), which are the active ingredients in Yin–Chen–Hao–Tang (YCHT), performing drug‐interaction pharmacokinetics studies in vivo. Plasma samples were prepared using methanolic precipitation, a filtration step, and then injection of the methanolic extract onto a Nova‐Pak C18 Guard‐Pak? guard column with a gradient mobile phase. Triple‐wavelength diode array detection was set at λmax values of 343 nm for D, 241 nm for the G, and 259 nm for R. Our results successfully demonstrate that this method has excellent and satisfactory selectivity, sensitivity, linearity, precision, accuracy and recovery. In healthy rats, the estimated pharmacokinetic parameters (i.e. Cmax, AUC and Cl) of D, G and R, when administered with COC (a combination of D, G and R), were Cmax 16.05 mg/L, AUC 108.96 mg h/L and Cl 0.36 L/h for D; Cmax 9.35 mg/L, AUC 64.71 mg h/L and Cl 0.88 L/h for G; and Cmax 14.18 mg/L, AUC 57.98 mg h/L and Cl 1.77 L/h for R. Here, we report that the COC combination could significantly increase the plasma level and slow the elimination rate compared with any one or two of the three individual compounds, which may indicate a drug–drug interaction. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献