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991.
992.
Jonas Brisman Jeong‐Lim Kim Anna‐Carin Olin Kjell Torén Björn Bake 《Clinical physiology and functional imaging》2017,37(6):640-645
New spirometric reference equations for Swedish adults are required. Three different older sets of reference equations clinically used in Sweden have various drawbacks and the recently published ‘The Global Lung Function 2012 (GLI) equations’ have been shown not to be adequate for Swedish normal, healthy non‐smokers. We have recently concluded that a piecewise linear model presented by Lubinski and Gólczewski accurately describes the distribution of spirometric variables in a large Swedish random population sample. This piecewise linear model also offers the important advantage of implementing easily physiologically interpretable coefficients. The present study aimed at presenting piecewise linear reference equations for Swedish adults based on a random population sample of 6685 individuals aged 25–75 years. Predicted normal values by the piecewise linear reference equations and lower limit normal (LLN) were compared with the three reference equations frequently used clinically in Sweden and the GLI equations. We found predicted normal values according to the present piecewise linear reference equations close to 100% predicted normal as expected, whereas the other equations either overestimated or underestimated normal subjects. Concerning LLN, the present equations, i.e. 1·645 × RSD, showed the least deviation from the expected 5% and, e.g., the GLI equations systematically identified too few subjects below LLN. We conclude that the present piecewise linear reference equations, based on a relatively large general population sample, ought to be considered for clinical use in Sweden. Application of 1·645 × RSD below predicted value gave an acceptably accurate LLN. 相似文献
993.
Miyeoun Song Woo Kyung Moon Yunhee Kim Dongyeol Lim In-Chan Song Byung-Woo Yoon 《Korean journal of radiology》2007,8(5):365-371
OBJECTIVE: We wanted to compare the human neural stem cell (hNSC) labeling efficacy of different superparamagnetic iron oxide nanoparticles (SPIONs), namely, ferumoxides, monocrystalline iron oxide (MION), cross-linked iron oxide (CLIO)-NH(2) and tat-CLIO. MATERIALS AND METHODS: The hNSCs (5 x 10(5) HB1F3 cells/ml) were incubated for 24 hr in cell culture media that contained 25 microg/ml of ferumoxides, MION or CLIO-NH(2), and with or without poly-L-lysine (PLL) and tat-CLIO. The cellular iron uptake was analyzed qualitatively with using a light microscope and this was quantified via atomic absorption spectrophotometry. The visibility of the labeled cells was assessed with MR imaging. RESULTS: The incorporation of SPIONs into the hNSCs did not affect the cellular proliferations and viabilities. The hNSCs labeled with tat-CLIO showed the longest retention, up to 72 hr, and they contained 2.15+/-0.3 pg iron/cell, which are 59 fold, 430 fold and six fold more incorporated iron than that of the hNSCs labeled with ferumoxides, MION or CLIO-NH(2), respectively. However, when PLL was added, the incorporation of ferumoxides, MION or CLIO-NH(2) into the hNSCs was comparable to that of tat-CLIO. CONCLUSION: For MR imaging, hNSCs can be efficiently labeled with tat-CLIO alone or with a combination of ferumoxides, MION, CLIO-NH(2) and the transfection agent PLL. 相似文献
994.
MR imaging of the alar ligament: morphologic changes during axial rotation of the head in asymptomatic young adults 总被引:2,自引:0,他引:2
OBJECTIVE:. The alar ligament plays a critical role in limiting the axial rotation of the head, the left alar ligament being stretched on rotation to the right and vice versa. The purposes of this study were to assess the usefulness of MR imaging in demonstrating the alar ligament and also to identify its morphologic changes during axial rotation of the head in asymptomatic young volunteers. DESIGN AND PATIENTS:. Twenty-two healthy volunteers participated in this study. All subjects underwent four series of contiguous fast spin echo density-weighted MR images with a 2 mm slice thickness including axial and coronal images with the head in neutral position, and coronal images with alternate head rotation to the right and left. The alar ligaments seen on each series of MR images were visually graded 0-2, and grade comparisons were performed between the four series of MR images. We also assessed the morphologic changes of the alar ligament on coronal images during axial rotation of the head. RESULTS:. Grade comparisons for the demonstration of the alar ligament revealed that each of three series of coronal images was statistically significantly better in grade than axial images. During axial rotation of the head, MR images showed rather constant morphologic changes of the alar ligament: elevation and wrapping of the contralateral alar ligament around the dens, associated with slightly upward movement of C1-C2 on that side. This wrap-around effect of the contralateral alar ligament in relation to the dens sometimes caused the apparent shortening of the alar ligament on that side. CONCLUSION:. Reliable assessment of the anatomy and function of the alar ligament can be achieved with MR imaging, preferably in coronal planes. MR imaging with the aid of a functional study may be a valuable imaging modality in the evaluation of alar ligament failure. 相似文献
995.
Objective
Both endovascular coil embolization and microsurgical clipping are now firmly established as treatment options for the management of cerebral aneurysms. Moreover, they are sometimes used as complementary approaches each other. This study retrospectively analyzed our experience with endovascular and microsurgical procedures as complementary approaches in treating a single aneurysm.Methods
Nineteen patients with intracranial aneurysm were managed with both endovascular and microsurgical treatments. All of the aneurysms were located in the anterior circulation. Eighteen patients presented with SAH, and 14 aneurysms had diameters of less than 10 mm, and five had diameters of 10-25 mm.Results
Thirteen of the 19 patients were initially treated with endovascular coil embolization, followed by microsurgical management. Of the 13 patients, 9 patients had intraprocedural complications during coil embolization (intraprocedural rupture, coil protrusion, coil migration), rebleeding with regrowth of aneurysm in two patients, residual sac in one patient, and coil compaction in one patient. Six patients who had undergone microsurgical clipping were followed by coil embolization because of a residual aneurysm sac in four patients, and regrowth in two patients.Conclusion
In intracranial aneurysms involving procedural endovascular complications or incomplete coil embolization and failed microsurgical clipping, because of anatomical and/or technical difficulties, the combined and complementary therapy with endovascular coiling and microsurgical clipping are valuable in providing the best outcome. 相似文献996.
Shen-Yang Lim Ai Huey Tan Susan H. Fox Andrew H. Evans Soon Chai Low 《Current neurology and neuroscience reports》2017,17(1):3
Parkinson’s disease (PD) is a complex motor and non-motor disorder and management is often challenging. In this review, we explore emerging approaches to improve the care of patients, drawing from the literature regarding patient-centred care, patient and caregiver perspectives and priorities, gaps in knowledge among patients and caregivers and the need for accurate information, individual variability in disease manifestations, prognostication of disease course, new developments in health technologies and personalized medicine, specialty care, pharmacological and non-pharmacological management, financial burden, lifestyle and work-related issues, support groups and palliative care. 相似文献
997.
Preoperative transarterial embolization of spinal tumor: embolization techniques and results 总被引:6,自引:0,他引:6
Shi HB Suh DC Lee HK Lim SM Kim DH Choi CG Lee CS Rhim SC 《AJNR. American journal of neuroradiology》1999,20(10):2009-2015
BACKGROUND AND PURPOSE: The techniques of preoperative embolization of hypervascular spinal tumors, which has been known to be helpful for completing tumor resection, have not been described in detail. The purpose of this study was to analyze the technique and to evaluate the safety and value of preoperative transarterial embolization of hypervascular spinal tumors. METHODS: Eighteen patients with hypervascular spinal tumors underwent transarterial embolization before surgery. The lesions were located between the upper cervical and lower lumbar spine: C1-T1 (n = 6), T5-L3 (n = 11), and L5 (n = 1); they arose intradurally in six patients and extradurally in 12. Thirty-one arteries were embolized with polyvinyl alcohol (PVA) particles (150-500 microm), and, in 18 of these, pieces of gelatin sponge were added for proximal pedicular embolization. The criteria for judging the effectiveness of embolization were completeness of tumor removal and estimated blood loss during surgery. RESULTS: Tumor embolization was total in eight patients, nearly total in seven, subtotal in one, and partial in two. There were no symptomatic complications associated with embolization. Tumors were totally removed in 17 patients and nearly totally removed in one. The average estimated blood loss during surgery was 1100 mL (range, 200-6000 mL) for all 18 patients, and 1540 mL in patients with extradural tumors. CONCLUSION: Preoperative embolization of hypervascular spinal tumors is safe and effective. It can make complete resection of a tumor possible and can make an unresectable tumor resectable. Superselection or flow control is necessary to achieve effective devascularization and to avoid complications. 相似文献
998.
999.
Discogenic lumbar pain: association with MR imaging and CT discography 总被引:10,自引:0,他引:10
OBJECTIVE: To correlate MR and CT discography findings with pain response at provocative discography in patients with discogenic back pain. MATERIALS AND METHODS: Forty-seven patients aged 25-54 years who underwent MR imaging and subsequent CT discography (97 discs) were included in this study. MR images were retrospectively evaluated regarding disc degeneration, endplate abnormalities, facet joint osteoarthritis, and high intensity zone. During discography concordant pain was regarded as positive, whereas discordant pain and no pain were regarded as negative. MR and CT discographic findings were analyzed on the base of concordant pain using the Chi-square test. RESULTS:: Concordant pain was significantly common in the following (P < 0.05): grade 4 or 5 disc degeneration [88% (30/34) in concordant pain versus 48% (30/63) in discordant pain and no pain], high intensity zone [56% (19/34) versus 30% (19/63)], combination of above two findings [53% (18/34) versus 25% (16/63)], fissured and ruptured disc at discogram [94% (32/34) versus 57% (36/63)], and contrast beyond inner annulus at CT discogram [97% (33/34) versus 57% (36/63)]. CONCLUSION: Typical MR findings with concordant pain at discography include grade 4 or 5 disc degeneration and presence of a high intensity zone. Typical CT discography findings with concordant pain were fissured/ruptured discs and contrast extending into/beyond the outer annulus on CT. 相似文献
1000.
OBJECTIVE: To evaluate expectation and knowledge on obstetric ultrasound examination in the first and second trimester in a Chinese population. METHOD: A cross-sectional survey was conducted in a university obstetric clinic in Hong Kong. Chinese pregnant women who underwent the first trimester early scan sessions, or the second trimester anomaly scan sessions were invited to complete a self-administered questionnaire, which contained items on their knowledge, expectation, and sociodemographic characteristics. RESULTS: In all 276 eligible pregnant women (117 in the first trimester and 159 in the second trimester) were recruited. Although 249 women (90.2%) claimed they understood the indication of the ultrasound examination, only 93 of them were correct (33.7%). The median perceived overall-detection rate for structural abnormalities was 66.5%. Living in Hong Kong for more than 7 years was significantly associated with higher knowledge level and expectation from ultrasound examination. Attaining tertiary education level was also significantly associated with higher knowledge level. Over 90% of the pregnant women studied wished to know the fetal gender from the anomaly scan examination. CONCLUSION: Knowledge of Chinese pregnant women on ultrasound was generally unsatisfactory. Understanding their limitation of knowledge and expectations helps to devise appropriate education in the local setting. 相似文献