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991.
Y. Cao  W. He 《Acta biomaterialia》2013,9(1):4558-4568
Implantable microelectrode arrays (MEA) hold enormous hope for individuals with sensory or motor deficits. However, long-term function of MEA remains a critical hurdle. The objective of this study was to synthesize an antioxidant prodrug that can be delivered to the neural tissue around the implant and present a pharmacological depot to combat the injurious oxidative stress around the MEA. In this report, monomers of triethylene glycol methyl acrylate and α-tocopheryl acrylate, a synthetic derivative of the antioxidant α-tocopherol (vitamin E, Ve), were copolymerized to obtain poly(triethylene glycol methyl acrylate-co-α-tocopheryl acrylate) (PVT) with different compositions. In contrast to the poor water solubility of Ve, solubility of the PVT prodrug in water can reach as high as 3.1 mg ml?1 (equivalent to 500 μM Ve) by tuning the copolymer composition. To demonstrate the applicability of the prodrug for MEA implants, PVT was successfully deposited on silicon substrates with poly(acrylic acid) (PAA) or tannic acid (TA) using the layer-by-layer technique mediated by hydrogen bonding. Ellipsometry and quartz crystal microbalance data showed that the multilayers of PAA/PVT were destructible at physiological pH. In contrast, multilayers of TA/PVT were stable. The PVT prodrug was non-cytotoxic toward A172 human astrocytes. Furthermore, PVT was able to protect astrocytes against oxidative stress exerted by H2O2 in vitro. Using a free radical scavenging assay, the protection mechanism was attributed to the hydrolysis of the labile ester linkage and release of the active Ve.  相似文献   
992.
选用冠心病介入治疗中常用的7个投照体位,在没有辐射防护情况下分别测量第一操作者在不同高度体表所受的入射剂量,并绘制体表入射剂量分布图。结果是重要辐射剂量区域内剂量峰值都出现在20~70 cm高度;在130~160cm高度出现剂量次高峰。投照体位以左脚位(spider位)时入射剂量最大。  相似文献   
993.
结肠镜下进行大肠息肉切除共2 256例,分为无痛组1 229例和常规组1 027例。无痛组治疗时间为(14.2±2.8)min,常规组为(18.1±3.2)min(P<0.05);成功率无痛组为97.25%,常规组为92.36%,(P<0.05);满意程度无痛组明显提高(P<0.05);腹痛腹胀、血管迷走反射和术中体动等不良反应无痛组显著低于常规组(P<0.01);舌后坠、头晕等不良反应无痛组显著高于常规组(P<0.01或0.05);肠道穿孔等严重并发症发生率两组无明显差异。  相似文献   
994.
Synovial sarcoma is an uncommon, aggressive malignant tumor of the soft tissues primarily involving the extremities of young adults. Head and neck synovial sarcoma is rare, and its diagnosis and therapy are still challenging.We report a case of a young patient with synovial sarcoma, clinically masquerading as cystic mass of the neck and malignant second branchial cleft cyst. The pathological diagnosis of the sarcoma was confirmed by a multimodality diagnostic protocol, including histological, immunohistochemical and molecular genetic analysis. The patient underwent complete surgical excision followed by postoperative radiotherapy and recovered well.  相似文献   
995.
Biglycan (BGN), an extracellular matrix component, has been reported to play a crucial role in the tumor progression of various cancers. However, the relation between the expression of BGN and clinical prognosis has not been studied yet. We therefore carry out the present study to elucidate the role of BGN in predicting outcomes of patients with esophageal squamous cell carcinoma (ESCC). In this study, the expression of BGN in 170 cases of ESCC tissues and matched 46 adjacent non-tumorous tissues was measured by quantitative real-time PCR and immunohistochemistry. Upregulation of BGN occurred in approximately 60% of primary ESCCs compared with their non-tumor counterparts. In addition, high expression of BGN was significantly associated with clinical stage (P = 0.009), tumor invasion (P = 0.006) and lymph node metastasis (P = 0.046). The 5-year disease-specific survival (DSS) in high expression of BGN group is poorer than that in low level expression group (36.8% VS 57.4%, P = 0.006). Stratified analysis according to the pathological stage revealed its discernibility on DSS was only pronounced in patients with advanced clinical stage (P = 0.010). Cox multivariate analysis revealed that pathologic N category (P < 0.001; hazard ratio, 2.482, 95% CI, 1.576-3.909) and BGN expression (P = 0.019; hazard ratio, 1.713, 95% CI, 1.092-2.688) were two independent prognostic factors. The findings of the present study provide evidence that BGN represents a potential novel prognostic biomarker for resected ESCC patients in advanced clinical stage.  相似文献   
996.
Purpose: To study the effect of gonadotropin-releasing hormone II (GnRHII) on the cell apoptosis of ectopic, eutopic and normal endometrial stromal cells cultured in vitro from endometriosis patients, and to provide theoretical basis for exploring new treatments for endometriosis (EMs). Methods: Ectopic, eutopic and normal endometrial stromal cells were isolated, cultured and identified in vitro, then treated with different concentrations of GnRHII (0, 10-10 M, 10-8 M and 10-6 M). Cell apoptosis was detected by Hoechst staining and flow cytometry. Results: GnRHII increased apoptosis in ectopic, eutopic and normal stromal cells in a dosage-dependent manner (P<0.05), and apoptosis of ectopic stroma cells was significantly higher than that of eutopic and normal cells (P<0.05); apoptosis in eutopic and normal cells had no different (P>0.05). Conclusion: GnRHII can significantly induce apoptosis in ectopic, eutopic and normal endometrial stromal cells from patients with endometriosis, especially to the ectopic.  相似文献   
997.
Histiocytoid breast carcinoma (HBC) is a rare type of breast cancer with a controversial histogenesis. Here we describe a case report of a 65-year old woman with HBC. The patient presented with two masses in the right breast. Histopathologically, the tumors consisted of a diffuse infiltration of large tumor cells and histological components of carcinoma in situ and atypical lobular hyperplasia were also observed. The infiltration pattern was similar to that of invasive lobular carcinoma with targetoid and Indian file arrangements. The invasive histiocytoid cells had finely granular, eosinophilic to vesicular cytoplasm and nuclei with a bland uniform appearance, a single small eosinophilic nucleolus and finely granular chromatin. We compared the immunohistochemical profiles of 17 breast cancer markers between invasive carcinoma, carcinoma in situ, atypical lobular hyperplasia and normal breast epithelium. Although they all shared the same reactivity for many of the proteins, they exhibited differences in GCDFP-15, E-cadherin, P120, CEA, HER-2, ER and PR expression, and these are discussed. This is the first case study of two HBC masses occurring in one breast simultaneously. By analyzing and comparing their morphologic characteristics and spectrum of immunohistochemical expression, our study supports the view that HBC is a variant of lobular carcinoma and our findings may assist in future diagnoses of HBC.  相似文献   
998.
999.
1000.
颈前路多节段融合术后吞咽困难的原因分析   总被引:3,自引:0,他引:3       下载免费PDF全文
目的 比较多节段颈前路椎间盘切除减压融合术中采用传统钢板+cage和“零切迹”颈椎椎间融合器植入患者术后吞咽困难的发生情况,并分析其原因.方法 2008年9月至2011年9月,接受颈前路椎间盘切除减压+前路钢板+cage植入的118例多节段颈椎病患者为钢板cage组,接受颈前路椎间盘切除减压+Zero-p颈椎椎间融合器植入的108例患者为Zero-p组.分别于术前、术后第2天、术后3、6、12个月及末次随访时采用日本矫形外科学会评分法(Japan orthopedic association,JOA)对患者的神经功能情况进行评估;摄颈椎X片评价植骨融合程度、内固定相关并发症及椎前软组织肿胀程度;采用Bazaz吞咽困难分级及改良吞咽生活质量量表(swallowing-quality of life,SWAL-QOL)评估患者吞咽困难的发生率及相关症状发生情况.结果 随访时间平均为2.4年(1.0~3.5年).术后第2天钢板cage组发生吞咽困难49例(41.53%)明显高于Zero-p组(36例,33.33%);钢板cage组术后第2天及术后2个月椎前软组织厚度明显大于Zero-p组.术后第2天Zero-p组中手术范围为C3~C6的患者吞咽困难发生率(43.1%)明显高于手术范围为C4~C7的患者(22%).结论 颈前路多节段融合术后吞咽困难不可避免,内固定的选择和手术范围是术后吞咽困难发生的重要影响因素.使用颈椎“零切迹”植入物可以减少术后吞咽困难的发生率,手术节段越高术后吞咽困难的发生率越高.  相似文献   
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