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31.
目的探讨开放性乳突病变切除术后加速乳突术腔上皮化及缩小乳突术腔的有效办法。方法63例行开放性乳突病变切除术的患者按照复查治疗方法分为两组,异种脱细胞真皮组36例,应用异种脱细胞真皮基质覆盖术腔,碘仿纱条组27例,以碘仿纱条填塞术腔。术后随访两组患者,对比观察术腔愈合情况和上皮化时间。结果异种脱细胞真皮组术腔上皮化时间为2~4周,平均2.2周;碘仿纱条组术腔上皮化时间为9~35周,平均13.7周,异种脱细胞真皮组的上皮化时间短于碘仿纱条组(P〈0.01)。结论异种脱细胞真皮基质可促进上皮组织再生,减少术后感染及肉芽发生,加速乳突腔上皮化,提高开放性乳突病变切除术的疗效。  相似文献   
32.
The effect of allogeneic and syngeneic extracts from the spleens of male and female inbred mice on primary cultures of fibroblasts obtained from the subcutaneous connective tissues of fetuses of CBA and C57BL/6J mice was studied. The cytotoxic and growth-inhibiting action on the cultures was successively enhanced by the use of extracts from syngeneic male and allogeneic female and male tissues. Consequently, an increase in the degree of antigenic difference between the target cells and extracts led to enhancement of the phenomenon of allogeneic inhibition. It was shown for the first time that in a syngeneic system extracts from male tissues (containing the weak H-Y antigen) have a cytotoxic action on cells from female inbred mice, i.e., that they induce a reaction of the allogeneic inhibition type.Research Laboratory of Experimental Immunobiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Zhukov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi biologii i meditsiny, Vol. 86, No. 10, pp. 486–488, October, 1978.  相似文献   
33.
The anatomical location of the squamous cell carcinoma (SCCA) within the oral cavity and oropharynx influenced the association of SCCA with the biomarker in vitro hyperdiploidy in human dermal fibroblast cultures (IVH). There was a strong association of IVH with the occurrence of SCCA in the anterior 2/3 of the tongue, floor of the mouth and lower alveolar ridge of the oral cavity and in the base of the tongue and pharyngeal wall of the oropharynx. There was a lower association of SCCA with IVH in the tonsillar region of the oropharynx. IVH showed no association with SCCA located in other anatomical parts of the oral region. The patient group whose diagnosis of SCCA in the anterior 2/3 of the tongue occurred prior to the age of 50 years were invariably IVH-, whereas those diagnosed after the age of 50 years were IVH+, providing evidence for heterogeneity. There was no such correlation of biomarker subgrouping with age of diagnosis demonstrated for SCCA at any other anatomical location within the oral cavity or oropharynx.  相似文献   
34.
Two Mannich-base prodrugs of 5-iodo-2-deoxycytidine (5-IDC) have been synthesized. The prodrugs exhibit increased lipid solubility compared to 5-IDC and rapidly revert to 5-IDC in buffer. One of the prodrugs delivered about twice as much 5-IDC from isopropyl myristate (IPM) through hairless mouse skin in diffusion-cell experiments as did 5-IDC from IPM. Subsequent applications of theophylline/ propylene glycol onto the diffusion cells to determine the effect of prodrug/IPM, 5-IDC/IPM, or IPM on the resistance of the skins to subsequent applications showed that the prodrug/IPM had no more effect than IPM itself.  相似文献   
35.
 异基因造血干细胞移植(allo-HSCT)是治愈恶性血液病的有效手段,但移植患者因接受感染乙型肝炎病毒(HBV)的移植物、免疫功能严重受损等原因,术后并发乙型病毒性肝炎的风险增加。恩替卡韦和替诺福韦是目前公认用于预防allo-HSCT后乙型病毒性肝炎的有效药物,显著减少移植后患者的肝损伤。移植后患者的免疫重建时间长且重建规律存在异质性,导致术后监测和预防性抗HBV治疗的最佳持续时间尚未能明确。本文对allo-HSCT后HBV再激活的发生机制、乙型病毒性肝炎的特点及防治的最新研究进展进行综述。  相似文献   
36.
The current standard for composite tissue preservation is static cold storage (SCS) and is limited to 6 h until irreversible muscle damage occurs. Extracorporeal perfusion (ECP) is a promising technique for prolonged preservation, however, functional results have been scarcely researched. This article assessed neuromuscular function and compared results to histological alterations to predict muscle damage after ECP. Forelimbs of twelve Dutch landrace pigs were amputated and preserved by 4 h SCS at 4–6 °C (n = 6) or 18 h mid-thermic ECP with University of Wisconsin solution (n = 6). Limbs were replanted and observed for 12 h. Sham surgery was performed on contralateral forelimbs (n = 12). Histology analysis scored four subgroups representing different alterations (higher score equals more damage). Muscle contraction after median nerve stimulation was comparable between ECP, SCS, and sham limbs (P = 0.193). Histology scores were higher in ECP limbs compared to SCS limbs (4.8 vs. 1.5, P = 0.013). This was mainly based on more oedema in these limbs. In-vivo muscle contraction was well preserved after 18 h ECP compared to short SCS, although histology seemed inferior in this group. Histology, therefore, did not correlate to muscle function at 12 h after replantation. This leads to the question whether histology or neuromuscular function is the best predictor for transplant success.  相似文献   
37.
38.
Allogeneic peripheral blood stem cell transplantation for leukemia   总被引:3,自引:0,他引:3  
Objective To observe engraftment kinetics, the incidence and severity of graft-versus-ho st disease (GVHD), and clinical outcome on 40 recipients undergoing allogeneic p eripheral blood stem cell transplantation (allo-PBSCT).Methods From June 1997 to May 1999, forty leukemia patients with a median age of 35 year s underwent allo-PBSCT. PBSC were mobilized with G-CSF at a dose of 5 μg/kg s.c. every 12 hours for 5 days. A median of 7.7 (2.0-16.8)×10 (6) CD34(+) cells/kg was infused into the recipients. Busulfan-cyclophosphamid e (BU-CY) was used as the conditioning regimen. All patients received cyclospo rine A and either methotrexate (n=34) or methylprednisolone (n=6) for GVHD p rophylaxis. Results Engraftment of neutrophils and platelets was achieved at a median of 13 days (9 -28 days) and 12 days (7-60 days) respectively. Patients receiving ≥4×10 (6) CD34(+) cells/kg or given G-CSF post transplant had significantl y accelerated neutrophil and platelet engraftment. Acute GVHD occurred in 17 of 40 patients (42.5%), with grade Ⅱ-Ⅳ acute GVHD in 10 patients (25%). Chron ic GVHD developed in 21 (9 extensive, 12 limited) out of 30 evaluable patients ( 21/30, 70%) with a median follow up of 380 days (180-900 days). Transplan t related mortality was 17.5% and the relapse rate was 10%. The probability of leukemia free survival at 3 years was 72.5%.Conclusion Allo-PBSCT can provide rapid hematopoietic reconstitution without an increased incidence of acute GVHD, but may be associated with a high risk of chronic GVHD .  相似文献   
39.
异基因外周血干细胞的动员,检测及临床移植的应用研究   总被引:1,自引:0,他引:1  
目的:探讨异基因外周血干细胞移植(allo-PBSCT)供者经G-CSF或G-CSF+GM-CSF动员后,采集的外周血干细胞(PBSC)移植物中的幼稚粒细胞与单个核细胞(MNC)、CD34^+细胞及CFU-GM之间的相关性和移植的剂量标准及临床应用效果。方法:对11例allo-PBSCT供者用G-CSF(9例)或G-CSF+GM-CSF(2例)进行动员,于动员前及动员后,分别对外周血及MNC惧物中的幼稚粒细胞、CD34^+细胞及CFU-GM进行检测计数,预处理方法主要用大剂量环磷酰胺(CTX)+全身照射(TBI)。结果:动员后外周血中的幼稚粒细胞与CD34^+细胞及CFU-GM同步增加,外周血MNC中的幼稚粒细胞数与CD34^+细胞数及CFU-GM有较好的相关性。11例患者全部植活和恢复造血功能,并为染色体核型  相似文献   
40.
目的 :探讨异基因外周血干细胞移植 (allo- PBSCT)治疗重症再生障碍性贫血的疗效。方法 :患者诊断为重症再生障碍性贫血 ,预处理方案为大剂量环磷酰胺 (CTX) 全身照射 (TBI) ,用粒细胞集落刺激因子 (G- CSF)连续 5 .5 d对供者进行外周血干细胞动员后分 2天采集单个核细胞 ,并于采集当日由静脉输给患者 ,移植后给予预防移植物抗宿主病 (GVHD)措施。 结果 :患者迅速恢复造血功能 ,于 0 d血小板≥ 2 0× 10 9/ L, 14d白细胞 >1.0× 10 9/ L。 14d骨髓增生活跃 ,性染色体核型转变为供者型 (46 ,XY) ,随访至今不变。结论 :allo- PBSCT是治疗重症再生障碍性贫血的有效手段。  相似文献   
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