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51.
Between 1980 and 1994, 162 cases of endocrine based hypertension were diagnosed and treated surgically. Seventy-nine cases (48.7%) of phaeochromocytoma, 63 cases (38.8%) of Cushing's syndrome, and 20 cases (12.3%) of Conn's syndrome were diagnosed. In phaeochromocytoma 75% of the tumours arose from the adrenal glands and 25% arose from the extra-adrenal sites. Cushing's syndrome was caused by adenoma (45%), diffuse bilateral adrenal hyperplasia (36%), pigmented macronodular hyperplasia (9%), and adrenal carcinoma (10%). The most common cause of Conn's syndrome was adenoma (95%) which arose mainly from the left adrenal gland (60%). In the present series the success rate of surgical treatment was 100% for phaeochromocytoma, 90% for Cushing's syndrome and 96% for Conn's syndrome. Trucut biopsy of the kidneys of these patients showed hypertensive changes, the moderate hypertension could be due to renal damage.  相似文献   
52.
Marine organisms are proven to be rich source of secondary metabolites that can be used to treat various diseases. Excavatolide B (Exc.B), the most abundant metabolite was found in the marine coral Briareum excavatum exhibits cytotoxic effects against lung cancer cell. Treatment of the A549 cells with Exc.B significantly reduced its cell viability and induced cell cycle arrest at subG1 phase in a dose‐ and time‐dependent manner, respectively. Apoptosis induction by Exc.B was further confirmed by decreased pro‐caspase 3 expressions and increased proteolytic cleavage of poly (ADP‐ribose) polymerase (PARP) expression. Furthermore, Exc.B increased reactive oxygen species (ROS) and reactive nitrogen species (RNS) and also decreased the antioxidant enzymes such as, Catalase, GPx, SOD, GST, and GSH. The proteomic analysis data revealed that total thirty six proteins were altered by Exc.B. STRING database showed that most of the altered proteins have no interaction between each other. Based on these data, KSR1, RuVBL2, PPAR‐γ, and Tenascin X proteins were chosen to validate the 2DE data by Western blotting. Additional experiments demonstrated that Exc.B induced PTEN expression and inhibited pAKT and NF‐kB expression. These results provide a novel insight into mechanisms underlying the inhibition of A549 cells growth by excavatolide B. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 290–301, 2017.  相似文献   
53.
54.
Aluminum doped zinc oxide (ZnO:Al) thin films were deposited on soda-lime glass substrates by the chemical spray technique. The atomization of the solution was carried out by ultrasonic excitation. Six different starting solutions from both unmilled and milled Zn and Al precursors, dissolved in a mix of methanol and acetic acid, were prepared. The milling process was carried out using a planetary ball mill at a speed of 300 rpm, and different milling times, namely, 15, 25, 35, 45, and 60 min. Molar concentration, [Al]/[Zn] atomic ratio, deposition temperature and time, were kept at constant values; 0.2 M, 3 at.%, 475 °C, and 10 min, respectively. Results show that, under the same deposition conditions, electrical resistivities of ZnO:Al thin films deposited from milled precursors are lower than those obtained for films deposited from unmilled precursors. X-ray diffraction analysis revealed that all films display a polycrystalline structure, fitting well with the hexagonal wurtzite structure. Changes in surface morphology were observed by scanning electron microscopy (SEM) as well, since films deposited from unmilled precursors show triangular shaped grains, in contrast to films deposited from 15 and 35 min milled precursors that display thin slices with hexagonal shapes. The use of milled precursors to prepare starting solutions for depositing ZnO:Al thin films by ultrasonic pyrolysis influences their physical properties.  相似文献   
55.

Background

This paper presents the methodology for assessing and selecting the most appropriate procedure for the preparation of nanoparticles by implementing the analytical network process. The commonly utilized nanoparticle preparation methods are Polymer Precipitation, Interfacial polymer deposition, Complex Coacervation, Cross linking, Emulsion solvent diffusion, Homogenization and Polymerization method. There are numerous parameters to be considered in groundwork of nanoparticles that departs the conclusion manufacturer in bias. One has to address a number of components in alignment to determine and choose the optimum conclusion choices, because an unsuitable conclusion could lead to the eventual merchandise having to be formulated and developed again. For this cause in this paper, we study selecting the most appropriate procedure for the preparation of nanoparticles utilizing one of the multi criteria-decision making techniques, Analytic Network Process.

Methodology

The main goal was determined. The criteria and sub-criteria that affect the main goal were determined. The alternatives for the problem were determined. The interactions between criteria, sub-criteria, and alternatives respect to the main goal were determined. The super matrixes according to the network were assembled and then weighted super matrix and limit super matrix were then constructed. The values of this limit matrix are the desired priorities of the elements with respect to the goal. The alterative with the highest priority was finally chosen as the best alternative.

Results

The emulsion solvent diffusion technique (M-5) has the highest value (0.434379) among the alternative methods that are applicable to the preparation of the nanoparticles. The second highest is Polymer Precipitation (M-1) with a value of 0.178798, and the lowest value or last choice is Cross Linking (M-4) with a value of only 0.024516. The alternative with the highest priority would achieve the goal, i.e., the best method for the preparation of the nanoparticles.

Conclusion

The alternative M5 emulsion solvent diffusion technique, scoring 0.434379 was the one with largest main concern amidst all the other alternatives and thereby judged to be the most apt procedure for the preparation of nanoparticles.  相似文献   
56.

Introduction

Root canal treatment of maxillary molars presenting with complex root canal configurations can be diagnostically and technically challenging.

Methods

Nonsurgical endodontic therapy of a left maxillary first molar with three roots and eight root canals was successfully performed. This unusual morphology was diagnosed using a dental operating microscope (DOM) and confirmed with the help of cone-beam computed tomography (CBCT) images.

Results

CBCT axial images showed that both the mesiobuccal and distobuccal root contained a Sert and Bayirli type XV canal, whereas the palatal root showed a Vertucci type II canal configuration.

Conclusions

The use of a DOM and CBCT imaging in endodontically challenging cases can facilitate a better understanding of the complex root canal anatomy, which ultimately enables the clinician to explore the root canal system and clean, shape, and obturate it more efficiently.  相似文献   
57.
The present study is to analyze the CyberKnife hypofractionated dose distribution of localized prostate cancer in terms of high–dose rate (HDR) brachytherapy equivalent doses to assess the degree of HDR brachytherapy resemblance of CyberKnife dose distribution. Thirteen randomly selected localized prostate cancer cases treated using CyberKnife with a dose regimen of 36.25 Gy in 5 fractions were considered. HDR equivalent doses were calculated for 30 Gy in 3 fractions of HDR brachytherapy regimen. The D5% of the target in the CyberKnife hypofractionation was 41.57 ± 2.41 Gy. The corresponding HDR fractionation (3 fractions) equivalent dose was 32.81 ± 1.86 Gy. The mean HDR fractionation equivalent dose, D98%, was 27.93 ± 0.84 Gy. The V100% of the prostate target was 95.57% ± 3.47%. The V100% of the bladder and the rectum were 717.16 and 79.6 mm3, respectively. Analysis of the HDR equivalent dose of CyberKnife dose distribution indicates a comparable resemblance to HDR dose distribution in the peripheral target doses (D98% to D80%) reported in the literature. However, there is a substantial difference observed in the core high-dose regions especially in D10% and D5%. The dose fall-off within the OAR is also superior in reported HDR dose distribution than the HDR equivalent doses of CyberKnife.  相似文献   
58.
Selecting the right method for the preparation of nanoparticles is a crucial decision. A wrong decision can result in the product having to be formulated and developed again. One tool that can be useful in determining the most appropriate method is the Analytical Hierarchy Process (AHP). AHP has been employed in almost all areas related to decision-making problems. In this paper, the results of a case study illustrate that the AHP concept can assist designers in the effective evaluation of various methods available for the preparation of nanoparticles. This paper presents the methodology of selecting the most suitable method for preparing nanoparticles using the analytical hierarchy process.  相似文献   
59.
60.
A commercial metal oxide silicon field effect transistor (MOSFET) dosimeter of model TN502-RD has been characterized for its linearity, reproducibility, field size dependency, dose rate dependency, and angular dependency for Cobalt-60 (60Co), 6-MV, and 15-MV beam energies. The performance of the MOSFET clearly shows that it is highly reproducible, independent of field size and dose rate. Furthermore, MOSFET has a very high degree of linearity, with r-value > 0.9 for all 3 energies. The calibration factor for 2 similar MOSFET detectors of model TN502-RD were also estimated and compared for all 3 energies. The calibration factor between the 2 similar MOSFET detectors shows a variation of about 1.8% for 60Co and 15 MV, and for 6 MV it shows variation of about 2.5%, indicating that calibration should be done whenever a new MOSFET is used. However, the detector shows considerable angular dependency of about 8.8% variation. This may be due to the variation in radiation sensitivity between flat and bubble sides of the MOSFET, and indicates that positional care must be taken while using MOSFET for stereotactic radiosurgery and stereotactic radiotherapy dosimetric applications.  相似文献   
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