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991.
992.
Michael F. Sarosdy 《World journal of urology》1997,15(2):103-106
Summary The BTA Test is an adjunctive test for the diagnosis and management of bladder cancer. For estimation of its potential in the management of patients with transitional-cell cancer (TCC) a review of published results was undertaken. Three prospective studies were analyzed, in which a total of 699 patients with a history of TCC were enrolled. The BTA Test was performed on voided urine and compared with either voided-urine or bladder-wash cytologic analysis in a blinded fashion. In all three studies the sensitivity of the BTA Test was more than double that of cytology, irrespective of whether the cytologic analysis was performed on voided or bladder-wash samples. The third study also included an additional 225 patients undergoing evaluation for hematuria, and TCC was found in 67 cases. The BTA Test detected 70% of these tumors, whereas cytology detected only 25%. The BTA Test is a simple, rapid test that can diagnose a substantial percentage of patients having new or recurrent bladder TCC. Its complete role in the management of such patients remains to be defined. 相似文献
993.
G J Michael 《Australasian physical & engineering sciences in medicine / supported by the Australasian College of Physical Scientists in Medicine and the Australasian Association of Physical Sciences in Medicine》1992,15(2):75-87
A new dual-energy x-ray CT algorithm is presented which makes use of both pre- and post-reconstruction data in an iterative manner to achieve accurate beam hardening correction and decomposition into basis materials. The technique does not require a calibration phantom and also does not require accurate estimation of the effective energies of the polyenergetic x-ray beams. It does however, require a knowledge of the incident x-ray spectra. For the situation where the incident spectra are unknown, a method is given whereby sufficiently accurate approximations to the spectra can be determined from attenuation measurements. Decomposition into basis materials makes use of spatial and energy information and an 'a priori' knowledge of the composition and attenuating properties of various tissue types. Any total number of basis materials may be used within the limitation that a subset containing a maximum of three materials is used for any individual pixel. Results of a computer simulation show that the algorithm produces accurate measurements of the concentrations of both high and low atomic number materials such as bone mineral, collagen, fat and air. However the results of a phantom study show that the measurement of the concentrations of low atomic number basis materials may be subject to systematic errors arising from uncertainties in the published values of linear attenuation coefficients. 相似文献
994.
Juha-Matti Savola Michael Hill Mia Engstrom Hannele Merivuori Siegfried Wurster Steven G McGuire Susan H Fox Alan R Crossman Jonathan M Brotchie 《Movement disorders》2003,18(8):872-883
Previous studies in the MPTP-lesioned primate model of Parkinson's disease have demonstrated that alpha(2) adrenergic receptor antagonists such as idazoxan, rauwolscine, and yohimbine can alleviate L-dopa-induced dyskinesia and, in the case of idazoxan, enhance the duration of anti-parkinsonian action of L-dopa. Here we describe a novel alpha(2) antagonist, fipamezole (JP-1730), which has high affinity at human alpha(2A) (K(i), 9.2 nM), alpha(2B) (17 nM), and alpha(2C) (55 nM) receptors. In functional assays, the potent antagonist properties of JP-1730 were demonstrated by its ability to reduce adrenaline-induced (35)S-GTPgammaS binding with K(B) values of 8.4 nM, 16 nM, 4.7 nM at human alpha(2A), alpha(2B), and alpha(2C) receptors, respectively. Assessment of the ability of JP-1730 to bind to a range of 30 other binding sites showed that JP-1730 also had moderate affinity at histamine H1 and H3 receptors and the serotonin (5-HT) transporter (IC(50) 100 nM to 1 microM). In the MPTP-lesioned marmoset, JP-1730 (10 mg/kg) significantly reduced L-dopa-induced dyskinesia without compromising the anti-parkinsonian action of L-dopa. The duration of action of the combination of L-dopa and JP-1730 (10 mg/kg) was 66% greater than that of L-dopa alone. These data suggest that JP-1730 is a potent alpha(2) adrenergic receptor antagonist with potential as an anti-dyskinetic agent in the treatment of Parkinson's disease. 相似文献
995.
Irwin S. Johnsrude William M. Bogey Jr Michael D. Tripp 《Cardiovascular and interventional radiology》1994,17(6):336-338
Discovery of a postlumbosacral discectomy fistula between the right iliac artery and vein was obscured by an associated severe stricture of the infrarenal inferior vena cava in a 49-year-old man. During venous stenting for treatment of peripheral edema, the fistula was suspected because of faint pulsatile right iliac vein flow and increased O2 saturation of the venous blood. The suspicion was confirmed on subsequent iliac arteriography. Surgical closure of the fistula with arterial interposition grafting was then performed. The patient improved substantially. 相似文献
996.
Mikael Bisrat Eva Karin Anderberg Michael I. Barnett Christer Nystr m 《International journal of pharmaceutics》1992,80(1-3):191-201
The dissolution rates of sparingly soluble, fine particulate, suspended drugs have been studied using a Coulter Counter Model TAII. For two sieve fractions of oxazepam the dissolution rates were monitored in media with varying viscosities brought about by the addition of glycerol, while for griseofulvin the change in the medium's viscosity was induced by changing the temperature. By calculating the dissolution rate, and compensating for differences in particle surface area and media solubility, it was shown that the dissolution rate was diffusion controlled. After additional normalization for the diffusion coefficient, it was suggested that the so-called apparent diffusional distance decreased substantially with particle size. The effect of particle size was more limited above approx. 15 μm. 相似文献
997.
998.
999.
Brigitte Maurer-Schultze Ioannis D. Bassukas Michael Böswald Markus Harasim 《Journal of cancer research and clinical oncology》1992,118(4):255-268
Summary Cell proliferation of 51 human renal cell carcinomas and 9 larynx and hypopharynx carcinomas has been studied in vitro and using xenotransplants. The proliferative activity ([3H]thymidine labelling index) increases during the first passages in nude mice and then remains almost constant throughout subsequent passages. A comparison of cell kinetic parameters of 8 human renal cell carcinomas, 1 hypopharynx and 2 larynx carcinomas, with data of xenografts and of human tumours in situ published up to now, shows that the cell kinetic parameters of human tumour xenografts presently studied range between those of human tumours in situ and those of autochthonous or transplantable mouse tumours. S-phase durations and potential doubling times are considerably shorter in xenotransplants than in human tumours in situ, whereas the cycle time is about the same. This means that the growth fraction increases considerably after xenotransplantation. This change of human tumour cell proliferation after transplantation into nude mice should be kept in mind if one wishes to draw conclusions from the nude mouse model on conditions in human beings, particularly with respect to therapeutic regimens, which are frequently tested in the nude mouse model.Abbreviations used RCC
renal cell carcinoma
- HPC
larynx or hypopharynx carcinoma
- LI
labelling index
- PLM
percentage of labelled mitoses
-
t
s
S-phase duration
-
t
c
cycle time
-
t
pot
potential doubling time
This work was supported by the Deutsche Forschungsgemeinschaft (Ma 876/2-1) 相似文献
1000.
Platelets stored in CLX™ blood bags, under normal blood banking conditions, were studied for up to 7 days to determine if changes ocurred in the levels of membrane glycoproteins (GP) Ib-IX and IIb-IIIa. Radiolabeled monoclonal antibodies (MAB) were used to estimate the number of glycoprotein molecules on the surface membrane of intact platelets. GP IX and GP IIb-IIIa levels remained essentially unaltered during storage. In contrast, the content of GP Ib at day 7 decreased by 45% of the total when fresh. The aggregation response to ristocetin, which requires GP Ib, was also diminished after 7 days. Addition of protease inhibitors, leupeptin and/or aprotinin did not appear to influence the degradation of this glycoprotein. We conclude that storage at 22°C has deleterious effects on the GP Ib content of platelets. 相似文献