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31.
Ijiri R Tanaka Y Kato K Misugi K Ohama Y Shinkai M Nishi T Aida N Kondo F 《Pathology international》2001,51(1):16-19
With the application of liver transplantation for patients with biliary atresia (BA), we have had the opportunity to review the clinicopathologic features of the native livers from 10 transplanted BA patients. A single large nodule at porta hepatis (hilar nodule) was noted in three of 10 patients, and an ill-defined nodule-like lesion at porta hepatis was present in two other patients. The three BA patients with hilar nodules were long-term survivors, compared to the patients with nodule-like and those without nodules. The hilar nodules measured between 5.0 cm and 8.0 cm and histologically, they were partly surrounded by fibrous septa with relatively well-preserved liver architectures and fewer inflammatory cells at the portal triads when compared to the surrounding cirrhotic lesions. No nuclear or cellular atypia was observed. Proliferating cell nuclear antigen labeling index was higher in the surrounding cirrhotic lesions than the hilar nodules. The nodule-like lesions at porta hepatis also showed similar light microscopic and immunohistochemical features as the hilar nodules. These hilar nodules did not seem to contain any malignant potential. The benign histology with relatively well-preserved liver architecture and the preferential site of occurrence at porta hepatis where bile seemed to flow more smoothly, suggested possible residues of less-affected hepatic tissues. 相似文献
32.
K. Taylor Wild Amy C. Goldstein Colleen Muraresku Rebecca D. Ganetzky 《American journal of medical genetics. Part A》2020,182(2):365-373
Pearson syndrome (PS) is a multisystem mitochondrial respiratory chain disorder typically characterized by sideroblastic anemia and exocrine pancreatic insufficiency. PS is caused by a single large‐scale mitochondrial DNA (mtDNA) deletion. PS classically presents in the first year of life and may be fatal in infancy. Children who survive PS may progress to develop Kearns–Sayre syndrome later in life. The full phenotypic spectrum and prognosis of the condition continue to evolve. Here we report five new patients with PS with unique clinical presentations, including four patients with onset later than previously reported in the literature, and one patient with prenatal onset of symptoms. The timing and unique features of these presentations support an expanded phenotypic spectrum of single large‐scale mtDNA deletion syndromes (SLSMDS) and reinforce the importance of including SLSMDS in the differential for children with complex multisystem presentations. 相似文献
33.
Cell proliferation may be evaluated by various methods, including Ki-67 immunohistochemistry and measures of telomerase activity. Both methods would theoretically show comparable increases in a given case. To evaluate the relationship between these 2 markers of proliferation in aggressive mature B-cell lymphomas, 48 cases were studied. The study group included 5 cases of mantle cell lymphoma (MCL); 6 cases of Burkitt's/Burkitt's-like lymphoma (BL); 9 cases of follicular lymphoma, grade 3 (FLC); and 28 cases of diffuse large B-cell lymphoma (DLC). Telomerase activity was measured as total product generated (TPG) units, and TPG results for the aforementioned cases were compared to the TPG results for 10 cases of reactive follicular hyperplasia. An overlap in TPG scores between reactive cases and lymphoma cases was found. Significant differences in both log TPG (P = 0.0443) and Ki-67 (P = 0.0006) were seen in the different lymphoma types. A positive correlation between Ki-67 percentage and TPG score was identified in FLC (r = 0.9281; P = 0.0003), but a poor correlation between these 2 indicators was seen in the other lymphoma types. Cluster analysis identified distinct patterns for MCL, FLC, and BL, but heterogeneous patterns for DLC. Because increases in both Ki-67 proliferation and telomerase activity are reported in normal germinal centers (GCs), these tests were also evaluated for usefulness as markers of a GC cell phenotype. Among the FLC and DLC cases, features of a GC phenotype significantly correlated with increased Ki-67 percentage (P = 0.0152), but not with increased log TPG. An elevated log TPG correlated with CD10 expression, and elevated Ki-67 percentage correlated with both CD10 and BCL-6 expression. TPG level and Ki-67 percentage did not correlate with the presence of t(14;18) or BCL-2 protein expression. Although the proliferation patterns were fairly distinctive for MCL, FLC, and BL, these studies show that markers of cell proliferation do not by themselves,identify distinct subtypes of large cell lymphomas. With the exception of FLC, the tumors exhibited poor correlation between telomerase activity and Ki-67 proliferation index. These tests did show some correlation with expression of GC cell phenotypic markers, however. 相似文献
34.
BACKGROUND: Tumor segment resection is one of the standard methods for the treatment of bone tumors. However, the reconstruction of bone defects atumor resection faces many challenges. A growing number of researchers are focusing on 3D-printed prostheses for bone defect repair and reconstruction following bone tumor surgery. OBJECTIVE: To explore the feasibility of 3D-printed prostheses in the reconstruction of large bone defect following bone tumor surgery and to evaluate the postoperative outcomes. METHODS: Retrospective analysis of clinical data of 24 patients [19 males and 5 females, age 23.8 (6-61) years] who underwent bone tumor resection and 3D-printed prosthesis implantation in the Department of Bone Oncology, the First Affiliated Hospital of Xinjiang Medical University from December 2020 to September 2021 was conducted. There were 7 cases with distal femur tumor, 5 with pelvis tumor, 4 with proximal tibia tumor, 3 with middle femur tumor, 1 with distal tibia tumor, 1 with proximal humerus tumor, 1 with middle humerus tumor, 1 with scapula tumor, 1 with ulna tumor, and 22 cases with primary tumors (13 osteosarcoma, 4 Ewing sarcoma, 2 giant cell tumor of bone, 1 chondroblastoma, 1 chondrosarcoma, and 1 osteoblastoma), 2 metastatic carcinoma. Preoperative and postoperative imaging data were recorded and neoadjuvant chemotherapy was administered in 17 cases before surgery. The Musculoskeletal Tumour Society score was used to assess limb function before surgery and 6 months after surgery, and pain was assessed by the Visual Analog Scale, as well as the complications were recorded. RESULTS AND CONCLUSION: (1) All patients undergoing resection of the tumor segment and 3D-printed prosthesis implantation for the reconstruction of the bone defect were followed for 6-49 months, and the results showed that the length of osteotomy was (18.2 ± 7.3) cm and an average intraoperative bleeding volume was 740 (100-3 000) mL. (2) Two patients died of systemic metastasis, the remaining 22 had no pulmonary metastasis or recurrence during the follow-up period, and 1 patient developed aseptic loosening of the prosthesis at 25 months postoperatively. (3) The Musculoskeletal Tumour Society scores were significantly increased, while Visual Analog Scale scores were significantly decreased (P < 0.05) at 6 months postoperatively. (4) The Musculoskeletal Tumor Society score was rated excellent in all 22 patients at the final follow-up. (5) These results suggest that 3D-printed prosthesis is suitable for the reconstruction of large bone defects caused by bone tumor resection. Patients have good postoperative function and few complications. However, further investigations are needed to explore long-term follow-up results. © 2023, Publishing House of Chinese Journal of Tissue Engineering Research. All rights reserved. 相似文献
35.
The purpose of the present paper was to examine the level of apoptosis and the relationships among apoptosis, apoptosis-associated proteins, and proliferating potential in lymphoma tissues to clarify the characteristics of apoptosis in diffuse large B-cell lymphomas (DLBCL) of the central nervous system (CNS). The formalin-fixed, paraffin-embedded tissues of CNS and non-CNS DLBCL (20 cases each) were studied by terminal deoxynucleotidyl transferase-mediated dUTP-nick end labeling (TUNEL) and immunohistochemistry, using antibodies against single-stranded DNA (ssDNA), cleaved caspase-3, bcl-2, bax, p53, Fas and Ki-67. The cleaved caspase-3 immunohistochemistry detected apoptosis of the lymphoma cells most sensitively compared to TUNEL and ssDNA immunohistochemistry. High expression (grade + + or + + +) of cleaved caspase-3 was found more frequently in CNS DLBCL (11 cases, 55%) than non-CNS DLBCL (three cases, 15%; P = 0.009). Bax-positivity of lymphoma cells was increased in six cases of CNS DLBCL, which also showed high positivity of cleaved caspase-3. There was no significant correlation between the cleaved caspase-3-positivity and the Ki-67 positivity. The present study indicates that the number of apoptotic cells and expression level of cleaved caspase-3 were significantly higher in CNS DLBCL than non-CNS DLBCL, and that the correlation of bax and cleaved caspase-3 expression was often present in CNS DLBCL. 相似文献
36.
Michael Frenken Alberto J. Kaumann 《Naunyn-Schmiedeberg's archives of pharmacology》1985,328(3):301-303
Summary Large coronary arteries of the dog were contracted with 5-hydroxytryptamine (5-HT). The 5-HT2-receptor antagonist ketanserin antagonized the 5-HT-induced effects. Unlike Brazenor and Angus (Europ J Pharmacol 81: 569–576, 1982), who reported insurmountable antagonism of the effects of 5-HT in dog coronaries, we found that the antagonism by ketanserin can be surmounted, provided the concentrations of 5-HT are high enough. Ketanserin also unmasked a saturable component of the 5-HT-induced contractions. Although ketanserin (0.1–1 mol/l) depressed the maximal force of the saturable component, it did not change its EC50 (-log mol/l 8.0). We conclude that large coronary arteries of dog are contracted by 5-HT mainly though 5-HT2-receptors and to a smaller extent through receptors different from 5-HT2. 相似文献
37.
38.
总结支气管动脉栓塞(BAE)治疗大咯血 84例,即时止血 78例,5例咯血明显减少,有效率 98.8%(83/84),1例止血无效。无严重并发症发生。认为(BAE)是目前治疗大咯血安全有效的治疗方法。 相似文献
39.
目的 :探讨自攻自断螺纹钉在大面积缺损牙保存性修复中的应用。方法 :采用自攻自断螺纹钉 ,选择凡因龋坏或者外伤使牙体组织损失残缺过大、牙髓未露、活力正常的牙进行修复。结果 :本组 5 0例经自攻自断螺纹钉进行固位修复 ,5年后随访 42例 ,除 2例因上颌磨牙牙尖折断而不能修复拔除外 ,其它 40例均达到评判标准 ,总成功率达 95 %。结论 :自攻自断螺纹钉主要用于对严重缺损而牙髓健康的牙进行保存性修复 ,还可对要做壳冠修复的牙进行牙壁加固。该方法因材料来源方便 ,临床效果显著 ,值得推广。 相似文献
40.