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991.
Nagahata M Abe Y Ono S Hosoya T Uno S 《AJNR. American journal of neuroradiology》2005,26(10):2508-2513
PURPOSE: Basiparallel anatomic scanning (BPAS)-MR imaging is a simple MR imaging technique that we designed for visualization of the surface appearance of the vertebrobasilar artery within the cistern. It can clearly show the outer contour of occluded arteries or thrombosed aneurysms. By comparing BPAS-MR imaging with 3D time-of-flight (TOF) MR angiography (MRA), we can precisely evaluate the vertebrobasilar artery condition. The purpose of this study is to determine the value of BPAS-MR imaging for brain MR examination. MATERIALS AND METHODS: We obtained BPAS-MR imaging, in addition to 3D TOF MRA, for 385 consecutive patients who underwent brain MR imaging and MRA in our hospital between April 1 and August 31, 2003. Their complaints varied from mild head symptoms to severe neurologic illness. Comparing BPAS-MR imaging with MRA, we revealed the character of BPAS-MR imaging and determined the role and value of displaying vascular outer contour. RESULTS: Although the cases did not represent a restricted group of vertebrobasilar diseases, BPAS-MR imaging contributed to accurate evaluation of the vertebrobasilar artery in 90 of our 385 patients (23.4%). Of particular note, 16.1% of our patients could not be evaluated accurately by MRA only. BPAS-MR imaging was useful to confirm hypoplastic or occluded vertebral arteries and to reveal the whole appearance of large or partially thrombosed aneurysms of the vertebrobasilar system. CONCLUSION: The combination of the BPAS-MR imaging and the 3D TOF MRA was necessary for accurate diagnosis in 16.1% of our ordinary patients. We should evaluate not only MRA but also the vascular outer contour revealed on BPAS-MR imaging, though its application is limited to the vertebrobasilar system and the screening use. 相似文献
992.
A case of hepatocellular carcinoma initially treated by carbon ions, followed by protons for marginal recurrence with portal thrombus 总被引:1,自引:0,他引:1
Mayahara H Oda Y Kawaguchi A Kagawa K Murakami M Hishikawa Y Igaki H Tokuuye K Abe M 《Radiation Medicine》2005,23(7):513-519
We report a case of hepatocellular carcinoma (HCC), initially treated by carbon ions, then subsequently by protons for marginal recurrence. A 52-year-old man with stage II HCC was enrolled in the clinical study for carbon ion therapy. A total dose of 52.5 GyE in 8 fractions was delivered through a right lateral port for 13 days. Dynamic CT performed 7 months after the initiation of carbon ion therapy showed a decrease in the size of the tumor. Dynamic CT performed 12 months after the therapy revealed marginal recurrence of HCC accompanied with portal vein tumor thrombus (PVTT). Proton therapy of 66 GyE in 22 fractions was delivered through posterior and right lateral ports for 33 days. Dynamic CT performed 3 months after the initiation of proton therapy showed a regression of the recurrent tumor and disappearance of the PVTT. No serious adverse effects were observed during or after these two treatments. He was free from further recurrence 27 months after the initiation of the first carbon ion therapy. Both carbon ions and protons were effective with minimal side effects. 相似文献
993.
Okuda R Kinoshita M Morikawa J Yasuda T Abe M 《The American journal of sports medicine》2005,33(1):35-42
BACKGROUND: There are few studies that have assessed the influence of focal chondral lesions on the results of ligament reconstruction for chronic lateral ankle instability. HYPOTHESIS: Focal chondral lesions do not influence the results of ligament reconstruction. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: Arthroscopic examination of the ankle was performed on 30 consecutive patients immediately before ligament reconstruction using the palmaris longus tendon. Clinical assessment was performed using the Karlsson scoring scale. A radiologic assessment was performed on stress radiographs of the ankle. Preoperative anteroposterior and lateral weightbearing radiographs of the ankle did not show any joint space narrowing in any ankle. The mean duration of follow-up was 38 months. RESULTS: On arthroscopy, focal chondral lesions were found in 19 ankles (63%). Chondral lesions were located on the medial side of the tibial plafond in 13 ankles (43%), on the lateral side in 2 ankles (7%), on the lateral side of the talar dome in 3 ankles (10%), and on the medial side in 9 ankles (30%). Postoperative mean Karlsson scores in patients without chondral lesions and in those with chondral lesions were 99.1 and 98.4 points, respectively. Postoperative mean talar tilt angles in patients without chondral lesions and in those with chondral lesions were 5.9 degrees and 4.7 degrees , respectively. There were no significant differences in the clinical and radiologic results between patients with chondral lesions and those without chondral lesions. CONCLUSIONS: Reconstruction of the lateral ligament can be successful regardless of the presence of focal chondral lesions in patients with chronic lateral ankle instability when preoperative weightbearing radiographs of the ankle do not show any joint space narrowing. 相似文献
994.
Contact area, contact pressure, and pressure patterns of the tendon-bone interface after rotator cuff repair 总被引:7,自引:0,他引:7
Tuoheti Y Itoi E Yamamoto N Seki N Abe H Minagawa H Okada K Shimada Y 《The American journal of sports medicine》2005,33(12):1869-1874
BACKGROUND: The contact pressure and contact area at the tendon-bone interface after the most commonly used rotator cuff repair methods have not been investigated. HYPOTHESIS: There are no significant differences among the transosseous, the single-row suture anchor, and the double-row suture anchor techniques in terms of contact pressure, contact area, and pressure patterns at the tendon-bone interface. STUDY DESIGN: Controlled laboratory study. METHODS: After creating a full-thickness supraspinatus tendon tear in 10 cadaveric shoulder specimens, we inserted pressure-sensitive film between the tendon stump and the bone, and we repaired the tear by (1) transosseous, (2) single-row suture anchor, and (3) double-row suture anchor techniques. RESULTS: The contact area of the double-row technique was 42% greater than that of the transosseous technique (P < .0001) and 60% greater than that of the single-row technique. The contact area of the transosseous technique was 31% greater than that of the single-row technique (P = .0015). The average pressures of the single-row and double-row techniques were 18% (P = .014) and 16% (P = .03) greater, respectively, than that of the transosseous technique, but there was no significant difference between the single-row and double-row techniques (P = .915). CONCLUSIONS: The double-row technique produced the greatest contact area and the second-highest contact pressure, whereas the single-row technique created the highest contact pressure and the least contact area. The transosseous technique produced the second-greatest contact area and the least contact pressure. CLINICAL RELEVANCE: The double-row suture anchor technique and the transosseous technique may provide a better environment for tendon healing. 相似文献
995.
Hiroshi?HojoEmail author Yoshikazu?Sasaki Naoya?Nakamura Michiko?Sato Masafumi?Abe 《Pediatric and developmental pathology》2004,7(3):250-257
Somatic mutation (SM) analysis provides a useful tool for understanding the stages at which neoplastic differentiate from normal B-cells. B-cell precursor neoplasms are considered to be somatically premutational. However, the variable frequency of SM of the variable region (VH) genes has been described in cases of precursor B-cell acute lymphoblastic leukemia (PB-ALL). To better characterize PB-ALL based on the differentiation stage, we investigated the SM of the VH genes expressed by tumor cells of the surface immunoglobulin (sIg)– HBL-3 cell line derived from childhood PB-ALL. In the HBL-3 cell line, the rearranged Ig heavy chain VH gene sequence showed no SM in the complementarity-determining regions of 1, 2, and 3, or in the framework regions of 1, 2, and 3 relative to the putative germline VH gene sequences. In addition, the VH segment of HBL-3 cells showed no intraclonal sequence heterogeneity, indicating ongoing SM. Our data demonstrated that HBL-3 cells express unmutated and developmentally regulated rearrangement of VH genes at the stage of B-cell precursor cells. HBL-3 cells, which are derived only from the sIg– PB-ALL, showed that SM cannot be recognized in VH genes of tumor cells before the expression of sIg. 相似文献
996.
Abe N Watanabe T Sugiyama M Yanagida O Masaki T Mori T Atomi Y 《American journal of surgery》2004,188(2):181-184
BACKGROUND: Although almost all (96%) the surgical cases of undifferentiated intramucosal early gastric cancer (EGC) have been found not to have lymph node metastasis (LNM), local treatment by endoscopic mucosal resection (EMR) is not accepted as an alternative treatment to surgery for this type of EGC. If a subgroup of patients with undifferentiated EGC with negligible risk of LNM can be defined, unnecessary surgery can be avoided. This study was conducted to determine this subgroup among undifferentiated EGC patients in whom the risk of LNM can be highly ruled out in an attempt to identify candidates who can be treated by EMR. METHODS: Data from 175 patients surgically resected for undifferentiated EGC were retrospectively collected, and clinicopathological factors were multivariately analyzed to identify predictive factors for LNM. RESULTS: Multivariate logistic regression analysis identified two independent risk factors for LNM, namely, a large tumor (>/=20 mm, P = 0.011) and presence of lymphatic involvement (P = 0.0005). Using these two risk factors as the predictive factors, LNM was observed in 5.8% of patients who had neither of the two predictive factors, whereas 23.1% or 13.1% of patients with one or two predictive factors had LNM, respectively. In contrast, the LNM rate was calculated to be 60% in patients who had both factors. Lymph node metastasis was not found in any of 6 patients with small intramucosal lesions (<10 mm) without lymphatic involvement. CONCLUSIONS: An intramucosal undifferentiated EGC that is smaller than 10 mm without lymphatic involvement can safely be treated by EMR alone, given the negligible possibility of LNM. When histological examination of endoscopically resected specimens shows lymphatic involvement or unexpectedly larger tumor size than that determined at pre-EMR endoscopic diagnosis, an additional surgical procedure should be considered. 相似文献
997.
Arimura H Li Q Korogi Y Hirai T Abe H Yamashita Y Katsuragawa S Ikeda R Doi K 《Academic radiology》2004,11(10):1093-1104
RATIONALE AND OBJECTIVES: A computerized scheme for automated detection of unruptured intracranial aneurysms in magnetic resonance angiography was developed based on the use of a three-dimensional selective enhancement filter for dots (aneurysms). MATERIALS AND METHODS: Twenty-nine cases with 36 unruptured aneurysms (diameter, 3 to 26 mm; mean, 6.6 mm) and 31 non-aneurysm cases were used in this study. The isotropic 3-dimensional magnetic resonance angiography images with 400 x 400 x 128 voxels (voxel size, 0.5 mm) were processed by use of the selective enhancement filter. The initial candidates were identified by use of a multiple gray-level thresholding technique on the dot-enhanced images and a region-growing technique with monitoring some image features. All candidates were classified into four types of candidates according to the size and local structures based on the effective diameter and skeleton image of each candidate (ie, large candidates and three types of small candidates including short-branch type, single-vessel type, and bifurcation type). In each group, a number of false-positives were removed by use of different rules on localized image features related to gray levels and morphology. Linear discriminant analysis was used for further removal of false-positives. RESULTS: With this computer-aided diagnostic scheme, all of 36 aneurysms were correctly detected with 2.4 false-positives per patient based on a leave-one-out-by-patient test method. CONCLUSION: This computer-aided diagnostic system would be useful in assisting radiologists for the detection of intracranial aneurysms in magnetic resonance angiography. 相似文献
998.
Kawaharada N Morishita K Hyodoh H Fujisawa Y Fukada J Hachiro Y Kurimoto Y Abe T 《The Annals of thoracic surgery》2004,78(3):846-851
Background
The purpose of this study was to determine whether the artery of Adamkiewicz (ARM) can be detected by magnetic resonance angiography and to determine the usefulness of preoperative magnetic resonance angiography evaluation of the ARM.Methods
Between April 2000 and December 2003, 120 patients underwent magnetic resonance angiography for detection of the ARM. The morphology of the anterior spinal artery at the ARM junction, as revealed by magnetic resonance angiography, in 99 patients in whom ARM was preoperatively detected was classified into the following three types: noncontinuation of the anterior spinal artery above the ARM junction (type A), continuation of the anterior spinal artery above and below the ARM junction (type B), and noncontinuation of the anterior spinal artery below the ARM junction (type C).Results
The ARMs were detected in 99 (83%) of 120 patients, and from a total of 110 ARMs 105 (95%) originated from intercostal arteries branching from the left side and 94 (86%) originated between Th9 and Th11. Two ARMs were found in 11 (11%) of 99 patients in whom ARMs were detected. In 107 patients, who underwent magnetic resonance angiography to reveal the morphology of the anterior spinal artery at the ARM junction, the patterns of the anterior spinal artery were type A in 59 patients (55%), type B in 21 patients (20%), type C in 3 patients (3%) and not classified in 24 patients (22%). No spinal cord injury occurred in patients in whom the ARM had been preoperatively detected.Conclusions
Preoperative detection of the ARM is possible by magnetic resonance angiography and is very useful for reducing the incidence of ischemic injury of the spinal cord. 相似文献999.
TNP-470, an angiogenesis inhibitor, suppresses the progression of peritoneal fibrosis in mouse experimental model 总被引:5,自引:0,他引:5
Yoshio Y Miyazaki M Abe K Nishino T Furusu A Mizuta Y Harada T Ozono Y Koji T Kohno S 《Kidney international》2004,66(4):1677-1685
BACKGROUND: In patients on long-term peritoneal dialysis (PD), angiogenesis and vasculopathy are observed in the peritoneum, and the degree of vascularization correlates with the area of fibrotic tissue, suggesting the involvement of angiogenesis in the progression of peritoneal fibrosis. The aim of the present study was to evaluate the effect of TNP-470, an anti-angiogenic compound, on the development of peritoneal fibrosis induced by chlorhexidine gluconate (CG). METHODS: Peritoneal fibrosis was induced by injection of CG into peritoneal cavity of Institute for Cancer Research (ICR) mice. TNP-470 was injected subcutaneously with CG. Mice were sacrificed, and peritoneal tissues were dissected out at days eight and 16 after CG and TNP-470 injection. The expression patterns of CD31 (as a marker of endothelial cells), vascular endothelial cell growth factor (VEGF), alpha-smooth muscle actin (as a marker of myofibroblasts), heat shock protein 47 (HSP47), type III collagen, F4/80 (as a marker of mice macrophages), proliferating cell nuclear antigen (PCNA), and cyclin-dependent kinase 2 (Cdk2) were examined by immunohistochemistry. RESULTS: CG-injected mice showed thickening of the submesothelial zone and increased number of vessels, myofibroblasts, and infiltrating macrophages. The expression levels of VEGF, type III collagen, and HSP47 were increased, and a large number of PCNA-positive cells and Cdk2-expressing cells were observed in the thickened submesothelial area. Treatment with TNP-470 suppressed the submesothelial zone thickening and reduced collagen III expression as well as angiogenesis. TNP-470 also decreased the number of VEGF-expressing cells, myofibroblasts, macrophages, PCNA-positive cells, and Cdk2-expressing cells. CONCLUSION: Our results indicate the involvement of angiogenesis in the progression of peritoneal fibrosis, and suggest that TNP-470 may be potentially useful for the prevention of peritoneal fibrosis through inhibition of angiogenesis and suppression of myofibroblast proliferation. 相似文献
1000.