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101.
The aim of this article is to assess the formation of new vital bone (VB) using histomorphometric analysis in alveolar ridge preservation (ARP), with and without primary closure. Eight patients needed bilateral tooth extraction and planned for ARP. All patients had a nonresorbable membrane with freeze-dried bone allograft after the extractions. Biopsies were obtained 6 months after ARP and were evaluated using histomorphometric analysis. The study included 6 males and 2 females, with an average age of 54.2 years (standard deviation, 9.7). The teeth requiring extraction included a bilateral canine (1 case), premolars (5 cases), and molars (2 cases). Histomorphometric values of new VB, residual bone (RB) substitute particles, and marrow tissue formation were 71.1 %, 16.2%, and 9.69% for closed flap and 50.9%, 15.3%, and 8.19 for open flap. P values were 0.066, 0.878, and 0.326, respectively. The present findings indicate that leaving the flap without primary closure did not have any effect on new VB, RB particles, and immature bone marrow compared with closed flap. However, the results favored the closed-flap technique.  相似文献   
102.
A series of substituted trifluoroketones were tested as inhibitors of mammalian liver microsomal carboxylesterase(s) hydrolyzing a variety of substrates including malathion, diethylsuccinate (DES) and p-nitrophenyl acetate (p-NpAc). The trifluoroketones used were very potent "transition state" inhibitors of crude mouse and human liver microsomal carboxylesterases as well as commercial porcine liver carboxylesterase (Sigma EC 3.1.1.1 Type I). These enzymes were found to differ in their sensitivity to the inhibitors employed, and some compounds caused dramatic activation of the hydrolysis of DES. In some but not all cases, a thioether beta to the carbonyl increased the inhibitory potency of the compound. Structure-activity relationships also were evaluated among aliphatic versus substituted and unsubstituted aromatic trifluoroketones. Kinetic parameters [i.e. Km, Vmax and (T1/2)e] for the mouse liver microsomes and the porcine carboxylesterase hydrolyzing DES were determined. Apparent high- and low-affinity forms were observed with each preparation. 3-Nonylthio-1,1,1-trifluoropropan-2-one was synthesized by the reaction of the corresponding thiol with 3-bromo-1,1,1-trifluoroacetone, and apparent synergism was observed when it was coadministered i.p. with malathion to mice.  相似文献   
103.
Nowadays, concretes blended with pozzolanic additives such as fly ash (FA), silica fume (SF), slag, etc., are often used in construction practices. The utilization of pozzolanic additives and industrial by-products in concrete and grouting materials has an important role in reducing the Portland cement usage, the CO2 emissions, and disposal issues. Thus, the goal of the present work is to estimate the compressive strength (CS) of polyethylene terephthalate (PET) and two supplementary cementitious materials (SCMs), namely FA and SF, blended cementitious grouts to produce green mix. For this purpose, five hybrid least-square support vector machine (LSSVM) models were constructed using swarm intelligence algorithms, including particle swarm optimization, grey wolf optimizer, salp swarm algorithm, Harris hawks optimization, and slime mold algorithm. To construct and validate the developed hybrid models, a sum of 156 samples were generated in the lab with varying percentages of PET and SCM. To estimate the CS, five influencing parameters, namely PET, SCM, FLOW, 1-day CS (CS1D), and 7-day CS (CS7D), were considered. The performance of the developed models was assessed in terms of multiple performance indices. Based on the results, the proposed LSSVM-PSO (a hybrid model of LSSVM and particle swarm optimization) was determined to be the best performing model with R2 = 0.9708, RMSE = 0.0424, and total score = 40 in the validation phase. The results of sensitivity analysis demonstrate that all the input parameters substantially impact the 28-day CS (CS28D) of cementitious grouts. Among them, the CS7D has the most significant effect. From the experimental results, it can be deduced that PET/SCM has no detrimental impact on CS28D of cementitious grouts, making PET a viable alternative for generating sustainable and green concrete. In addition, the proposed LSSVM-PSO model can be utilized as a novel alternative for estimating the CS of cementitious grouts, which will aid engineers during the design phase of civil engineering projects.  相似文献   
104.
A sensitive, selective, precise and stability‐indicating thin‐layer chromatographic (TLC) method was developed and validated for the analysis of noscapine, both as a bulk drug and in its formulation. The method employed TLC aluminium plates precoated with silica gel 60F‐254 as the stationary phase. The solvent system consisted of chloroform‐methanol (10:0.5 v/v). Densitometric analysis of noscapine and its degradation products was carried out in the absorbance mode at 254 nm. This system was found to give compact symmetrical spots for noscapine (Rf value 0.85 ± 0.04). Noscapine was subjected to acid and alkali hydrolysis, oxidation and photo degradation. The drug undergoes photo degradation and also degrades under acidic and basic conditions. The prepared degradation products were identified and verified through infrared (IR) and mass spectral analyses. The degraded products were also well resolved from the pure drug with significantly different Rf values and they were quantitatively determined. The method was validated for linearity, precision, robustness, limit of detection (LOD), limit of quantitation (LOQ), specificity and accuracy. Linearity was found to be in the 1.0–10.0 µg, 0.4–3.2 µg, 1.0–9.0 µg and 0.5–5.0 µg/band ranges for noscapine, cotarnine, meconine and opionic acid, respectively. The polynomial regression analysis for the calibration plots showed a good polynomial relationship with r2 of 0.9998, 9989, 9996 and 0.9997 for noscapine and its three degradation products, cotarnine, meconine and opionic acid, respectively. Statistical analysis proves that the method is repeatable and specific for the estimation of noscapine. As this approach could effectively separate the drug from its degradation products it can be employed as a stability‐indicating method in Quality Control laboratories. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
105.
Copper slag (CPS) is a large amount of waste material produced during the manufacture of copper. The disposal of this waste material becomes a problem for environmental concerns. Therefore, it is necessary to explore feasible alternate disposal options. They may also be utilized in concrete manufacturing to cut down on the usage of cement and natural aggregates. A lot of researchers focus on utilizing CPS in concrete, either as a cement replacement or as a filler material. This article aims to summarize the literature already carried out on CPS in conventional concrete to identify the influence of CPS on the fresh, hardened and durability performance of cement concrete. Results indicate that CPS improved the strength and durability performance of concrete but simultaneously decreased the slump value of concrete. Furthermore, an increase in the durability performance of concrete was also observed with CPS. However, the higher dose results declined in mechanical and durability aspects owing to a scarcity of flowability. Therefore, it is suggested to use the optimum dose of CPS. However, a different researcher recommends a different optimum dose ranging from 50 to 60% by weight of fine aggregate depending on the source of CPS. The review also recommends future researcher guidelines on CPS in concrete.  相似文献   
106.
Significant efforts have been made to improve adsorbents capable of eliminating pollutants from aqueous solutions, making it simple and quick to separate from the treated solution. In the current study, the removal of Crystal Violet Dye (CVD) from an aqueous synthetic solution onto a marine diatom alga, Skeletonema costatum, was investigated. Different experiments were conducted as a function of different pH, contact time, adsorbent dosage, temperature, and initial CVD concentration. The highest adsorption efficiency (98%) was obtained at 0.4 g of S. costatum, pH 3, and a contact time of 120 min, at 25 °C. Furthermore, Fourier-transform infrared spectroscopy (FTIR) results display that binding of CVD on S. costatum may occur by electrostatic and complexation reactions. Moreover, the Brunauer–Emmett–Teller surface area analysis (BET) obtained was 87.17 m2 g−1, which, in addition to a scanning electron microscope (SEM), reveals large pores that could enhance the uptake of large molecules. However, the equilibrium adsorption models were conducted by Halsey, Langmuir, Freundlich, Henderson, and Tempkin isotherm. In addition, multilayer adsorption isotherm best described the uptake of CVD onto S. costatum. The maximum monolayer adsorption capacity (qmax) was 6.410 mg g−1. Moreover, thermodynamic parameters of the adsorption studies suggested that the uptake of CVD onto S. costatum was endothermic and spontaneous. The pseudo-first-order, pseudo-second-order, and intra-particle diffusion kinetic equations were applied to model the adsorption kinetic data. It was seen that the kinetics of the adsorption may be described using pseudo-second-order kinetic equations. Finally, the present work concluded that the marine diatom alga S. costatum is suitable as a natural material for the adsorption of CVD.  相似文献   
107.
Prior studies in the literature show promising results regarding the improvements in strength and durability of concrete upon incorporation of glass fibers into concrete formulations. However, the knowledge regarding glass fiber usage in concrete is scattered. Moreover, this makes it challenging to understand the behavior of glass fiber-reinforced concrete. Therefore, a detailed review is required on glass fiber-reinforced concrete. This paper provides a compressive analysis of glass fiber-reinforced composites. All-important properties of concrete such as flowability, compressive, flexural, tensile strength and modulus of elasticity were presented in this review article. Furthermore, durability aspects such as chloride ion penetration, water absorption, ultrasonic pulse velocity (UPV) and acid resistance were also considered. Finally, the bond strength of the fiber and cement paste was examined via scanning electron microscopy. Results indicate that glass fibers improved concrete’s strength and durability but decreased the concrete’s flowability. Higher glass fiber doses slightly decreased the mechanical performance of concrete due to lack of workability. The typical optimum dose is recommended at 2.0%. However, a higher dose of plasticizer was recommended for a higher dose of glass fiber (beyond 2.0%). The review also identifies research gaps that should be addressed in future studies.  相似文献   
108.
A Proteus mirabilis-specific polymerase chain reaction (PCR) was developed and standardized. The origin of the primers was a recombinant clone that contained P. mirabilis-specific Hind III fragment DNA of 3.5-kilobase pairs. Based on the sequence data of P. mirabilis recombinant clone, two primers designated MMKAP 1 and MMKAP 2 were synthesized for use in the PCR. A P. mirabilis-specific 3.5-kb pair DNA product was amplified by the primers from 18 strains of P. mirabilis, but not from other Protease species and bacteria. The minimum amount of target DNA detected by P. mirabilis PCR was 10 fg using ethidium bromide/ultraviolet exposure of gels or Southern blot hybridization with a P. mirabilis recombinant DNA probe.  相似文献   
109.
A transverse sinus dural arteriovenous fistula (DAVF) not easily accessible by standard transfemoral (transarterial or transvenous) endovascular approaches is presented. An enlarged transosseous retromastoid foramen harboring the occipital artery branch feeding the lesion was identified on CT angiogram (CTA). Curative Onyx embolization was achieved via percutaneous CT-guided direct puncture of the transosseous occipital arterial branch followed by microcatheter navigation through the needle distally towards the site of the fistula.  相似文献   
110.
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