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991.
Multidrug resistance (MDR) is a huge challenge for gastric cancer chemotherapy. Therefore, MDR accurate monitoring is of great significance for the treatment of gastric cancer. GMBP1, an extracellular internalization peptide, can target MDR gastric cancer cells through specific binding to GRP78, which is an MDR-related protein that is overexpressed in gastric cancer cells. Herein, we constructed GMBP1 conjugated Mn3O4 nanoplates (Mn3O4@PEG-GMBP1 NPs) for in vivo monitoring of MDR gastric cancer through magnetic resonance imaging (MRI). The generated Mn3O4@PEG-GMBP1 NPs had a size of about 11 nm and exhibited a good colloidal stability in PBS and in 10% FBS medium. Serial in vivo MRI studies in mice demonstrated that the magnetic resonance signal intensity, at the tumor site, reached a peak at 3 h after tail vein injection of Mn3O4@PEG-GMBP1 NPs. The specific targeting ability of MDR gastric cancer cells (SGC7901/ADR) by Mn3O4@PEG-GMBP1 NPs was authenticated in vitro, in vivo and by immunofluorescence analysis experiments. The systematic safety evaluation indicated that the toxicity of Mn3O4@PEG-GMBP1 NPs in mice was negligible. Therefore, the GMBP1 conjugated Mn3O4 nanoplates can be clinically used for accurate imaging and monitoring of MDR gastric cancer.

GMBP1 conjugated manganese oxide nanoplates for in vivo monitoring multidrug resistance of gastric cancer through magnetic resonance imaging.  相似文献   
992.
Taxol (TAX) is a typical anticancer drug that is widely used in clinical treatment of cancer, while gold nanorods (AuNRs) are a kind of well-known material applied for photothermal therapy (PTT). The therapeutic outcome of TAX in chemotherapy is however limited by drug resistance, while AuNRs often show poor accuracy in PTT. To optimize the functions of TAX and AuNRs, we developed a hydrogen peroxide (H2O2)-triggered nanomaterial (LV–TAX/Au@Ag) for combined chemo-photothermal therapy. In normal tissues, TAX is protected in the lipid bilayer and isolated from the surrounding normal cells, while AuNRs are coated with silver shells and show low photothermal capacity. However, after reaching the tumor tissues, the silver shells can be etched by endogenous H2O2 in the tumor microenvironment, and the photothermal properties of AuNRs are then recovered. Meanwhile, the generated oxygen destabilizes the LV, which makes the 100 nm sized nanosystems disassemble into the smaller sized TAX and AuNRs, leading to the deep penetration and direct interaction with tumor tissues. The related in vitro experiments proved the validity of this “turn off/on” effect. Extensive necrosis and apoptosis were observed in the tumor tissues and the proliferation of solid tumor was greatly suppressed due to this combined chemo-photothermal therapy. In addition, no significant damage was found in normal tissues after the treatment of LV–TAX/Au@Ag. Therefore, the strategy to achieve environmental response by modifying the photothermal agents enhanced the efficiency and safety of nanomedicine, which may help improve cancer treatment.

Endogenous hydrogen peroxide was utilized to control the release of agents for better tumor therapeutic effect and safety.  相似文献   
993.
目的 探讨VD方案和VAD方案治疗多发性骨髓瘤的临床疗效和安全性.方法 回顾性分析了2008年6月到2011年6月我院收治的59例多发性骨髓瘤患者的临床资料,根据治疗方案将患者分为VD组(38例)和VAD组(21例),VD组接受硼替佐米联合地塞米松治疗,3周为一个疗程,治疗2个疗程;VAD组接受长春新碱、阿霉素联合地塞米松治疗,4周为一疗程,治疗2个疗程.分别对两组疗效和不良反应进行分析.结果 VD组和VAD组治疗缓解率分别为83.78%和59.09%,VD方案优于VAD方案,差异具有统计学意义(P<0.05).VD组主要不良反应为血液毒性和周围神经病变,症状较轻微,在停药和对症处理后症状消失或缓解.VAD组主要不良反应为感染、脱发和血液毒性等,其中感染多以3~4度为主.结论 VD方案治疗多发性骨髓瘤疗效优于VAD方案,不良反应轻微,患者可耐受,值得临床推广使用.  相似文献   
994.
目的 探讨老年骨质疏松性股骨颈骨折合并深静脉血栓形成的外科治疗方法及临床效果.方法 2010年2月至2012年6月对41例老年骨质疏松性股骨颈骨折合并深静脉血栓形成患者(平均年龄70岁以上,X线平片Singh指数在Ⅱ~Ⅳ度),均给予下腔静脉滤器植入联合骨水泥型双极人工股骨头置换术.结果 所有患者随访6~18个月,平均8个月,深静脉血栓症状全部缓解,髋关节Harris评分:术前平均41.4分,术后提高到88.4分,其中优28例,良9例,可3例,差1例,优良率90.2%(37/41).结论 下腔静脉滤器植入联合骨水泥型双极人工股骨头置换术,可确保股骨颈骨折合并深静脉血栓患者术后早期的康复锻炼和功能恢复.  相似文献   
995.
The aim of this study was to validate the advantages of the intrafascial nerve-sparing technique compared with the interfascial nerve-sparing technique in extraperitoneal laparoscopic radical prostatectomy. From March 2010 to August 2011, 65 patients with localized prostate cancer (PCa) underwent bilateral intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. These patients were matched in a 1∶2 ratio to 130 patients with localized PCa who had undergone bilateral interfascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy between January 2008 and August 2011. Operative data and oncological and functional results of both groups were compared. There was no difference in operative data, pathological stages and overall rates of positive surgical margins between the groups. There were 9 and 13 patients lost to follow-up in the intrafascial group and interfascial group, respectively. The intrafascial technique provided earlier recovery of continence at both 3 and 6 months than the interfascial technique. Equal results in terms of continence were found in both groups at 12 months. Better rates of potency at 6 months and 12 months were found in younger patients (age ≤65 years) and overall patients who had undergone the intrafascial nerve-sparing extraperitoneal laparoscopic radical prostatectomy. Biochemical progression-free survival rates 1 year postoperatively were similar in both groups. Using strict indications, compared with the interfascial nerve-sparing technique, the intrafascial technique provided similar operative outcomes and short-term oncological results, quicker recovery of continence and better potency. The intrafascial nerve-sparing technique is recommended as a preferred approach for young PCa patients who are clinical stages cT1 to cT2a and have normal preoperative potency.  相似文献   
996.
目的探讨关节镜技术和三柱锁定钢板治疗胫骨平台骨折的临床效果。方法采用关节镜技术和三柱锁定钢板固定治疗51例胫骨平台骨折,SehatzkerI~Ⅲ型35例,Ⅳ一Ⅵ型16例;其中,胫骨髁间嵴骨折并前交叉韧带损伤8例,后交叉韧带止点撕脱骨折8例,半月板损伤5例。结果本组随访12~24个月,平均13.6个月。膝关节功能参照Rasmussen评分:优24例,良20例,可6例,差1例,优良率达86.3%。无切口坏死,无固定失败及骨外露发生。有1例伤口感染。结论采用关节镜技术和三柱锁定钢板固定各种胫骨平台骨折是一种可靠方法。  相似文献   
997.
Orthopedic metallic prosthetic implants are commonly made of cobalt chromium (CoCr) alloys. However, such metal‐based implants are susceptible to fibrous capsule formation on the implant surface after implantation. At the bone‐implant interface, this capsule can prevent implant integration, resulting in loosening and failure. Minimizing the development of such a capsule on the CoCr surface would improve direct bone‐implant bonding leading to long‐term implant functionality. We evaluated the anti‐fibrosis effect of bone morphogenic protein‐7 (BMP‐7) peptide covalently bonded to CoCr alloy. This peptide, a biomimetic derivation of the knuckle epitope of BMP‐7, was conjugated at the N‐terminus with a cysteine amino acid. X‐ray photoelectron spectroscopy (XPS) and probe binding assay were used to evaluate different stages of grafting and surface functionalization using polydopamine coating. Cellular functions were studied using fibroblast attachment, cell proliferation, and MTT assays. Fibroblasts were grown on functionalized and pristine CoCr substrates, and the efficacy of BMP‐7 peptide on anti‐fibrosis was analyzed via gene expression and protein expression of fibrosis markers ACTA2, Collagen 1A1, and fibronectin. The peptide functionalized substrates showed significant reduction of fibrosis markers expression after 1 week of incubation compared to controls. BMP‐7 signaling pathway activation was shown by the presence of phosphorylation of Smad1/5/8. These findings may contribute to the improvement of CoCr implants in orthopedic surgery applications. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 983–990, 2013  相似文献   
998.
We conducted a systematic review of comparative clinical trials assessing the results of high tibial osteotomy (HTO) and unicompartmental knee arthroplasty (UKA) in patients with strictly unilateral osteoarthritis of the knee. A literature search was conducted through Medline, Embase and Cochrane library. A total of 11 comparative studies were included. Pooled results showed: UKA showed significantly better results compared to HTO in terms of function results, however, no difference in specific knee score was observed; HTO got slightly better results of the range of motion; a trend towards an increased velocity was found in UKA without significant difference. Postoperative rate of revision and complications did not differ significantly between two groups. With the correct patient selection, both HTO and UKA show effective and reliable results.  相似文献   
999.

Purpose

It is unclear whether volatile general anesthetics have sustained adverse effects on the immature brains of children. We performed a self-controlled study to evaluate the effects of strabismus surgery under sevoflurane-based general anesthesia on the cognitive function of pediatric patients.

Methods

The study included 100 children of ages 4 to 7 years old scheduled to undergo strabismus correction under sevoflurane-based general anesthesia. Cognitive function was tested 1 day before the operation (T1), 1 month after the operation (T2), and 6 months after the operation by the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) (Third Edition) method, which consists of 150 items. The scores at T1 were compared with scores at T2 and T3.

Results

Seventy-two children completed the three tests. At T1, they were 66.1 ± 7.7 months old and had a mean body weight of 21.6 ± 4.0 kg. The mean anesthesia time was 67.3 ± 9.8 min. The mean interval between T1 and T2 was 25.4 ± 6.8 days, and that between T1 and T3 was 182.1 ± 27.7 days. No statistically significant decrease in WPPSI scores was observed between T1 and T2, or between T1 and T3.

Conclusion

These findings from our self-controlled study show that sevoflurane-based general anesthesia does not have significantly adverse effects on the cognitive function of 4- to 7-year-old children at 1 month and 6 months after strabismus surgery. Additional studies with a larger sample size are needed.  相似文献   
1000.
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