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991.
D. V. Moiseev S. I. Marchenko A. M. Moiseeva T. V. Trukhacheva P. T. Petrov A. I. Zhebentyaev 《Pharmaceutical Chemistry Journal》2007,41(1):25-33
Pyrimidine derivatives are widely used for the treatment of viral diseases and cancer. The analysis of pyrimidine derivatives
is typically performed using various chromatographic techniques, in particular, reversed-phase high performance liquid chromatography
(HPLC). The separation is typically carried out with (7–30)-cm-long C8 and C18 silica gel columns, mainly at room temperature, and a 1–1.5 ml-min eluent flow rate. The column is eluted in an isocratic
or gradient system, and a variety of mobile phases have been proposed. The detection is based on optical absorption or fluorescence
measurements, or makes use of mass spectrometry. Various methods of extraction of pyrimidine derivatives from biological samples
are discussed, and the corresponding detection limits are presented.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 26–34, May, 2007. 相似文献
992.
M. G. Ismailova 《Pharmaceutical Chemistry Journal》2007,41(5):281-284
A new technology is developed for the production of activated charcoal (AU-L) tablets from cotton lignin, a readily available
local raw plant material. The physicochemical and technological properties of the parent substance (powder) have been studied
and the optimum composition of tablets has been determined. The best technological characteristics of both the initial mass
and the ready-to-use tablets are achieved for the composition involving a 3% methyl cellulose gel as a binding component and
microcrystalline cellulose as a filler. The qualitative characteristics of AU-L tablets have been studied and their sorption
capacity has been determined. The new technology will be implemented at the Tashkent Pharmaceutical Plant (Uzfarmprom Company).
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 5, pp. 49–52, May, 2007. 相似文献
993.
Y. O. Karatasso I. V. Logunova M. G. Sergeeva E. N. Nikolaev S. D. Varfolomeev V. V. Chistyakov 《Pharmaceutical Chemistry Journal》2007,41(3):166-169
A highly sensitive method for the quantitative determination of a potential antiarrhythmic drug (OF-7976) in the blood plasma
has been developed. The method is based on the electron spray ionization/mass spectrometry (ESI-MS) technique without preliminary
chromatographic separation and makes use of nibentan as the internal standard. A linear relationship between drug concentration
and the peak intensity of ions of the analyzed substance (m/z = 398) and the internal standard (m/z = 382) is established. The detection limit is 3 ng/(0.5 ml plasma). The method is linear from 3 to 25 ng/(0.5 ml plasma)
with a correlation coefficient of 0.98. The coefficient of variation was less than 7 %.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 3, pp. 45–48, March, 2007. 相似文献
994.
The amount of protein bound per 1 mL of the perfluorocarbon (PFC) emulsion depends on the emulsifier composition and the particle
size. A relationship between the amount of bound protein on the particle surface and the physicochemical parameters of the
PFC emulsion interaction with the blood serum, which indirectly characterize the surface properties of the PFC particles,
is established.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 12, pp. 40–43, December, 2007. 相似文献
995.
996.
D. M. Reid I. Mackay S. Wilkinson C. Miller D. G. Schuette J. Compston C. Cooper E. Duncan N. Galwey R. Keen B. Langdahl A. McLellan H. Pols A. Uitterlinden J. O’Riordan J. A. H. Wass S. H. Ralston S. T. Bennett 《Osteoporosis international》2006,17(1):125-132
Osteoporosis is a common disease with a strong genetic component characterized by reduced bone mass and an increased risk of fragility fractures. Bone mineral density (BMD) is the most important determinant of osteoporotic fracture risk, but the genes responsible for BMD regulation and fracture are incompletely defined. To enable multi-center studies to examine the genetic influences on BMD there is a requirement to standardize measurements across different manufacturers of bone densitometers, different versions of machines and different normative ranges. This paper describes a method developed to allow near-identical subjects with low age-adjusted BMD (based on Z-scores) to be recruited in 17 centers using 27 different densitometers. Cross-calibration was based on measurements using a European spine phantom circulated to all centers and measured ten times on each individual machine. From theses values an individual exponential curve, based on nominal versus observed BMD, was derived for each machine. As expected, there were large and significant variations in nominal BMD values, not only between scanners from different manufacturers but also between different versions of scanners from the same manufacturer. Hologic scanners tended to underestimate the nominal BMD, while Lunar scanners overestimated the value. Norland scanners gave mixed values over estimating BMD at the lower nominal value (0.5 g/cm2) while underestimating the value at the higher value (1.5 g/cm2). The validity of the exponential equations was tested using hip and spine measurements on 991 non-proband women from a familial osteoporosis study (FAMOS). After cross-calibration there was a considerable reduction in variation between machines. This observation, coupled with the absence of a similar reduction in variation attributable to a linear regression on age, demonstrated the validity of the cross-calibration approach. Use of the cross-calibration curves along with a standard normative range (in the case of this study, the Hologic normative range) allowed age-specific Z-scores to be used as an inclusion criterion in this genetic study, a method that will be useful for other trials where age-specific BMD inclusion criteria are required. 相似文献
997.
Prof. Dr. Wolfgang Dörr Sabine Köst Klaus Keinert Felix-Herbert Glaser Gerd Endert Thomas Herrmann 《Strahlentherapie und Onkologie》2006,182(1):1-8
PURPOSE: To compare tests for intestinal function with clinical scores after abdominal irradiation. PATIENTS AND METHODS: At the Department of Radiotherapy, Erfurt, Germany, intestinal changes were studied in 91 patients receiving abdominal radiotherapy between 1992 and 1996. Conventional fractionation (1.8-2 Gy per fraction, total doses 30.6-62.5 Gy) was applied. Before and at weekly intervals during radiotherapy, the clinical response was scored according to RTOG/EORTC for the upper and lower gastrointestinal (GI) tract. Resorption tests for vitamin B(12) and D-xylose were performed before the onset and immediately after treatment. RESULTS: The clinical response displayed a well-defined dose-effect relationship with grade 1 effects in 5% and 50% of the patients at about 10 Gy and 50 Gy, respectively. For grade 2 reactions, 5%- and 50%-effective doses were 20-30 Gy and 60-80 Gy. Effects in the upper and lower GI tract were highly correlated. Changes in body weight did not show a correlation with other clinical symptoms. Changes in resorption also displayed a significant dose effect. However, no correlation was found with the clinical symptoms in the individual patient. CONCLUSION: In the present study, the clinical manifestation of intestinal side effects according to RTOG/EORTC criteria was reflected by neither the vitamin B(12) nor by the D-xylose resorption test. Hence, these tests cannot be regarded as useful for objective quantitation of intestinal radiation injury. 相似文献
998.
999.
To evaluate use of a digital photostimulable phosphor imaging system in the neonatal nursery, 150 newborns were divided into three groups of 50. In the first two groups, screen-film and computed radiographs of the chest were obtained at the same radiation exposure; in the third group, computed radiographs were obtained with a 50% dose reduction (half-exposure computed radiographs). All images were blindly evaluated by three readers who scored the quality of visualization of the mediastinum, lung, bone, soft tissues, and endotracheal and nasogastric tubes, and also image density. No statistical differences in visualization of tubes existed among the three groups. Visualization of the mediastinum, lung, bones, and soft tissues was statistically significantly better on computed radiographs than on half-exposure computed radiographs; visualization of the lungs, bones, and soft tissues was statistically significantly better on screen-film radiographs than half-exposure computed radiographs. Image density was statistically better on computed and half-exposure computed radiographs than on screen-film radiographs. 相似文献