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991.
992.
Konstantin Golovine Peter Makhov Robert G Uzzo Alexander Kutikov David J Kaplan Eric Fox Vladimir M Kolenko 《Molecular cancer》2010,9(1):183
Background
Cadmium has been classified as a human carcinogen, affecting health through occupational and environmental exposure. Cadmium has a long biological half-life (>25 years), due to the flat kinetics of its excretion. The prostate is one of the organs with highest levels of cadmium accumulation. Importantly, patients with prostate cancer appear to have higher levels of cadmium both in the circulation and in prostatic tissues. 相似文献993.
Multivariate phenotypes are frequently encountered in genome‐wide association studies (GWAS). Such phenotypes contain more information than univariate phenotypes, but how to best exploit the information to increase the chance of detecting genetic variant of pleiotropic effect is not always clear. Moreover, when multivariate phenotypes contain a mixture of quantitative and qualitative measures, limited methods are applicable. In this paper, we first evaluated the approach originally proposed by O'Brien and by Wei and Johnson that combines the univariate test statistics and then we proposed two extensions to that approach. The original and proposed approaches are applicable to a multivariate phenotype containing any type of components including continuous, categorical and survival phenotypes, and applicable to samples consisting of families or unrelated samples. Simulation results suggested that all methods had valid type I error rates. Our extensions had a better power than O'Brien's method with heterogeneous means among univariate test statistics, but were less powerful than O'Brien's with homogeneous means among individual test statistics. All approaches have shown considerable increase in power compared to testing each component of a multivariate phenotype individually in some cases. We apply all the methods to GWAS of serum uric acid levels and gout with 550,000 single nucleotide polymorphisms in the Framingham Heart Study. Genet. Epidemiol. 34:444–454, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
994.
Fox LW 《The British journal of ophthalmology》1926,10(11):592-595
995.
The crescentic basilar first metatarsal osteotomy has been largely abandoned by the podiatric community in recent years in favor of proximal wedge-type osteotomies for the correction of metatarsus primus varus with large intermetatarsal angles. In most cases, this was due to the inherent instability of the osteotomy and difficulties with fixation. However, the crescentic osteotomy has the ability to correct in all three planes with less shortening than the wedge-type osteotomies. New fixation techniques, such as the small cannulated screw systems, have allowed for less technical difficulty in obtaining rigid internal fixation. In this article, the authors describe the results in 29 feet (27 patients) where the crescentic osteotomy was performed along with a metatarsaphalangeal joint procedure ranging from a McBride (with or without lateral sesamoidectomy) to a phalangeal osteotomy. Preoperative intermetatarsal angles ranged from 11 degrees to 22 degrees, with an average of 18.6 degrees. Postoperative intermetatarsal angles ranged from 2.6 degrees to 8.2 degrees with an average of 5.1 degrees. The preoperative hallux abductovalgus angles ranged from 25 degrees to 38 degrees, with an average of 33.6 degrees. The postoperative hallux abductovalgus angles ranged from 4 degrees to 18 degrees with an average of 11 degrees. Complications included one hallux varus, one delayed union, and three cases of superficial cellulitis that resolved with oral antibiotic therapy. 相似文献
996.
Androgen and estrogen receptors in adult zebra finch brain 总被引:1,自引:0,他引:1
L I Siegel E Akutagawa T O Fox M Konishi J A Politch 《Journal of neuroscience research》1986,16(4):617-628
Androgens and estrogens have been implicated in the activation of a variety of sexually-dimorphic, hormone-dependent behaviors in the adult zebra finch. In the present report, several biochemical characteristics of two putative sex steroid receptors, androgen- and estrogen-binding activities, were determined by DNA-cellulose chromatography in brain tissues from these birds. High-affinity, limited-capacity receptors for androgens and estrogens were found in cytosolic extracts of telencephalon, diencephalon-mesencephalon, and metencephalon-myelencephalon from adult male and female zebra finches. Androgen-binding activity reproducibly adhered to DNA-cellulose and was eluted within the 110-150 mM NaCl region of a linear salt concentration gradient. Estrogen receptors adhered to DNA-cellulose and exhibited elution maxima between 170 mM and 210 mM NaCl. Collectively these data indicate that brain regions of zebra finches contain steroid receptors that are similar to those found in the brains of other vertebrates and that their biochemical properties are similar in males and females. Quantitatively, males consistently exhibited higher androgen binding than females in both anterior and posterior telencephalic areas. Females treated with estradiol immediately after hatching exhibited adult levels of androgen binding corresponding to those detected in males. Masculinization of the androgen receptor system by early steroid exposure is discussed. 相似文献
997.
Venous clots: evaluation with MR imaging 总被引:2,自引:0,他引:2
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi. 相似文献
998.
Continuous ambulatory pulmonary artery pressure monitoring. A new method using a transducer tipped catheter and a simple recording system. 总被引:3,自引:3,他引:0
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R D Levy D Cunningham L M Shapiro C Wright L Mockus K M Fox 《Heart (British Cardiac Society)》1986,55(4):336-343
A transducer tipped catheter and simple recording system were used for the continuous measurement of ambulatory pulmonary artery pressure. The pulmonary artery pressure was recorded on a miniaturised tape recorder and replayed via an optical writer. Pulmonary arterial systolic and diastolic pressures can be analysed on a beat to beat basis. Continuous ambulatory monitoring was performed for a total 288 hours in 13 patients who were undergoing routine investigation for coronary artery disease. There was less than 1% zero drift and 0.25% linearity error per full scale pressure. The frequency response of the entire system was flat to 8 Hz with a linear phase delay. The transducer tipped catheter and a conventional fluid-filled system were used to measure left ventricular and pulmonary artery end diastolic pressures in eight patients. The correlation between the results obtained by the two methods was excellent. This method could be used at any centre equipped for ambulatory electrocardiographic monitoring. 相似文献
999.
Masataka Sakane Glen A. Livesay Ross J. Fox Theodore W. Rudy Thomas J. Runco S. L.-Y. Woo 《Knee surgery, sports traumatology, arthroscopy》1999,7(2):93-97
Ligaments and other soft tissues, as well as bony contact, all contribute to anterior stability of the knee joint. This study
was designed to measure the in situ force in the medial collateral ligament (MCL), anterior cruciate ligament (ACL), posterolateral
structures (PLS), and posterior cruciate ligament (PCL) in response to 110 N anterior tibial loading. The changes in knee
kinematics associated with ACL deficiency and combined MCL+ACL deficiency were also evaluated. Utilizing a robotic/universal
force-moment sensor system, ten human cadaveric knee joints were tested between 0° and 90° of knee flexion. This unique testing
system is designed to determine the in situ forces in structures of interest without making mechanical contact with the tissue.
More importantly, data for individual structures can be obtained from the same knee specimen since the robotic manipulator
can reproduce the motion of the intact knee. The in situ forces in the ACL under anterior tibial loading to 110 N were highest
at 15° flexion, 103 ± 14 N (mean ± SD), decreasing to 59.2 ± 30 N at 90° flexion. For the MCL, these forces were 8.0 ± 3.5
N and 38.1 ± 25 N, respectively. Forces due to bony contact were as high as 34.1 ± 23 N at 30° flexion, while those in the
PLS were relatively small at all flexion angles. Combined MCL+ACL deficiency was found to significantly increase anterior
tibial translation relative to the ACL-deficient knee only above 60° of knee flexion. These findings confirm the hypothesis
that there is significant load sharing between various ligaments and bony contact during anterior tibial loading of the knee.
For this reason, the MCL and osteochondral surfaces may also be at significant risk during ACL injury.
Received: 29 December 1997 Accepted: 16 July 1998 相似文献
1000.
Infant apnea 总被引:1,自引:0,他引:1
This review provides an understanding of current problems related to apnea of infancy. Methods for diagnosis, evaluation, and treatment of apnea are discussed. 相似文献