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71.
The objective of this study was to evaluate DNA repair capacity of cancer patients with the bleomycin (BLM) challenge test and the UVC challenge test. The human peripheral lymphocytes were collected from 33 patients with different kinds of cancers and 33 controls in the same hospital. The lymphocytes of each subject were divided into two groups: (1) In the BLM challenge test, the lymphocytes were treated with BLM (20 microgml(-1)) for 30 min, and repaired for 15 min. The DNA damage before and after BLM exposure was detected with comet assay to assess DNA repair capacity. (2) In the UVC challenge test, the lymphocytes were exposed to UVC (254 nm) at the dose of 1.5 Jm(-2). DNA damage of lymphocytes was measured before UVC exposure and at 90 and 240 min after UVC exposure using comet assay, then DNA repair percentage (DRP) was calculated. The results of this study indicate that the average DRPs of cancer patients were 75.63 +/- 3.11 and 68.98 +/- 4.19% calculated with tail length (TL) and tail moment (TM), respectively, in the BLM challenge test, which were significantly lower than those (91.11 +/- 1.09 and 88.19 +/- 1.71%) of controls (P < 0.01). Also, the mean DRPs of cancer patients were 49.19 +/- 3.47 and 58.27 +/- 3.64% calculated with TL and TM, respectively, in the UVC test, which were significantly lower than those (77.52 +/- 2.06 and 83.12 +/- 2.36%) of controls (P < 0.01). The correlation between the DRPs (%) drawn with TL and TM in the BLM test or between the DRPs (%) drawn with mean TL and mean TM in the UVC challenge test were significant (P < 0.05). The DNA repair capacity measured with the BLM and UVC challenge tests in 33 cancer patients was significantly lower than that in controls.  相似文献   
72.
作者从研究中发现:用Roberts铜盐法测定蔗汁样本葡聚糖含量时,所得结果与蔗汁的受热有关,受热蔗汁的测定值高于真实值,作者将这种现象暂称为Roberts铜盐法测定蔗汁样本葡聚糖含量的热效应。研究表明:蔗汁中的淀粉是引起热效应的重要因素。本文最后提出了一种由淀粉引起的热效应的可行校正方法。  相似文献   
73.
实验性顺铂诱导急性肾功能衰竭动物模型的研究   总被引:1,自引:0,他引:1  
1目的 建立顺铂 (cisplatin,CP)诱导的急性肾功能衰竭 (acute renal failure,ARF )大鼠模型 ,探讨 ARF的发病机制。2方法  SD大鼠静脉一次性注射 CP 6 mg/ kg,动态观察大鼠血清肌酐 (Scr)、尿素氮 (BUN)变化以及肾组织形态学改变。 3结果 对照组不同时间 Scr、BUN差异不明显 (P>0 .0 5 ) ,肾组织形态学正常。模型组 Scr、BUN第 4d较第 1d明显升高 (P<0 .0 5 )。肾组织形态学显示 ,肾脏髓质外侧带大部分肾小管坏死 ,细胞核固缩、溶解、消失 ,管腔扩张 ,有坏死脱落碎屑。 4结论  CP诱导的大鼠 ARF模型为一较为理想的 ARF模型  相似文献   
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76.
目的探讨适形切除保肛术(CSPO)与经括约肌间切除术(ISR)治疗低位直肠癌的临床疗效。方法采用回顾性队列研究方法。收集2011年8月至2020年4月2家医学中心收治的183例(海军军医大学附属长海医院117例、复旦大学附属华山医院66例)低位直肠癌病人的临床病理资料;男110例,女73例;年龄为(57±11)岁。183例病人中,117例行CSPO设为CSPO组,66例行ISR设为ISR组。观察指标:(1)两组低位直肠癌病人手术情况。(2)两组低位直肠癌病人术后并发症情况。(3)随访情况。(4)影响低位直肠癌病人预后因素分析。(5)影响低位直肠癌病人肛门满意度因素分析。采用门诊、问卷和电话方式进行随访,了解病人肿瘤局部复发及远处转移、病人生存、造口还纳、肛门满意度评分情况。正态分布的计量资料以x±s表示,组间比较采用t检验;偏态分布的计量资料以M(范围)表示。计数资料以绝对数或百分比表示,组间比较采用χ2检验。等级资料比较采用秩和检验。采用Kaplan-Meier法绘制生存曲线,采用寿命表法计算生存率,采用Log-rank检验进行生存情况分析。单因素分析采用线性回归,将单因素线性回归分析中P<0.10的变量纳入多因素分析。多因素分析采用COX逐步回归分析模型和线性回归分析。结果(1)两组低位直肠癌病人手术情况:CSPO组和ISR组病人腹腔镜手术例数、手术时间、术中出血量、肿瘤远切缘、术后化疗、术后住院时间分别为44例和55例、(165±54)min和(268±101)min、(142±101)mL和(91±85)mL、(0.6±0.4)cm和(1.9±0.6)cm、76例和9例、(6.6±2.5)d和(7.9±4.7)d,两组病人上述指标比较,差异均有统计学意义(χ2=35.531,t=8.995、-3.437、-3.088,χ2=44.681,t=2.267,P<0.05)。(2)两组低位直肠癌病人术后并发症情况:CSPO组术后19例病人发生并发症,其中Ⅰ级并发症6例,Ⅱ级并发症12例,Ⅲb级并发症1例。ISR组术后14例病人发生并发症,其中Ⅰ级并发症4例,Ⅱ级并发症7例,Ⅲa级并发症1例,Ⅲb级并发症2例。两组病人术后总体并发症发生情况比较,差异无统计学意义(χ2=0.706,P>0.05)。两组病人并发症经对症支持治疗后均好转。两组病人均无围术期(术后30 d内)死亡病例。(3)随访情况:183例病人均获得随访,CSPO组和ISR组随访时间分别为(41±27)个月和(37±19)个月,两组病人比较,差异无统计学意义(t=-1.104,P>0.05)。CSPO组和ISR组病人中,肿瘤局部复发分别为2例和3例、肿瘤远处转移分别为9例和4例,两组病人上述指标比较,差异均无统计学意义(χ2=1.277、0.170,P>0.05)。CSPO组和ISR组病人3年无病生存率分别为84.0%和88.6%,3年总体生存率分别为99.0%和92.8%,两组病人无病生存情况和总体生存情况比较,差异均无统计学意义(χ2=0.218、0.002,P>0.05)。CSPO组和ISR组分别有102例和66例病人随访至CSPO或ISR术后12个月,其造口还纳率分别为92.16%(94/102)和96.97%(64/66),两组病人比较,差异无统计学意义(χ2=1.658,P>0.05)。CSPO组8例造口未还纳病人中,2例因高龄、4例主观拒绝还纳、2例因放疗致瘢痕无法还纳。ISR组2例造口未还纳病人中,术后因肝转移和主观拒绝还纳各1例。CSPO组和ISR组分别有92例和61例病人随访至造口还纳术后12个月,其中CSPO组75例和ISR组38例完成肛门功能满意度调查。CSPO组和ISR组病人肛门功能满意度评分分别为(6.8±2.8)分、(5.4±3.0)分,两组病人比较,差异有统计学意义(t=-2.542,P<0.05)。CSPO组和ISR组病人肛门功能满意度评分>5分分别为54例和21例,两组病人比较,差异无统计学意义(χ2=3.165,P>0.05)。(4)影响低位直肠癌病人预后因素分析:COX逐步回归分析结果为性别、肿瘤pT分期是影响低位直肠癌病人无病生存率的独立影响因素(风险比=2.883,1.963,95%可信区间为1.090~7.622,1.129~3.413,P<0.05);性别、肿瘤pT分期是影响低位直肠癌病人总体生存率的独立影响因素(风险比=10.963,3.187,95%可信区间为1.292~93.063,1.240~8.188,P<0.05)。(5)影响低位直肠癌病人肛门满意度因素分析:单因素分析结果显示手术方式和肿瘤分化程度是影响低位直肠癌病人肛门满意度的影响因素(偏回归系数=1.464,-1.580,95%可信区间为0.323~2.605,-2.950~-0.209,P<0.05)。多因素分析结果显示:手术方式、肿瘤分化程度、术前放疗是影响低位直肠癌病人肛门满意度的独立影响因素(偏回归系数=1.637,-1.456,-1.668,95%可信区间为0.485~2.788,-2.796~-0.116,-2.888~-0.447,P<0.05)。结论与ISR比较,低位直肠癌施行CSPO同样可实现超低位保肛,不增加术后并发症发生率,保障肿瘤学安全性,改善肛门功能,提升病人术后肛门功能满意度。  相似文献   
77.

The relationship between the migration process and speciation distribution of Cr is important for the risk assessment in the underground environment. In this work, soil columns were collected from the chromate production site, with a 40-year operation, in the groundwater depression cone area of North China plain. The relationship between chromium pollution features and the geochemical properties of soil was established, and the migration risk of Cr(VI) was assessed based on the Nemerow composite index and Hydrus-1D model. The maximum total Cr concentration in the chromium slag dumping site reached 907 mg/kg, and that in the chromate production workshop was more than 200 mg/kg across the depth. The migration of Cr might be accelerated in the soil with abundant Mn (236–1461 mg/kg) but scarce organic matters (<?0.45%). The Hydrus simulation indicated that Cr(VI) would reach a cumulative flux of 300–729 mg/cm2 after 50 years.

  相似文献   
78.
Peanut allergy is one of the most severe food allergies due to its persistency and life-threatening character. Serum IgE from patients with documented peanut hypersensitivity reactions and synthetic peptides were used to screen the linear IgE-binding epitopes on the major peanut allergen, Ara h 1. Five major epitopes that bound peanut-specific serum IgE from more than 60% of patients tested were identified. Mutational analysis of the immunodominant epitope showed that single amino acid changes had dramatic effects on IgE-binding characteristics. Mapping and characterisation of the IgE-binding epitopes on Ara h1 could be used in future immunotherapeutic approaches for peanut allergy disease.  相似文献   
79.
Overexpression of decoy receptor (DcR) 3 protein, a recently discovered member of the tumor necrosis factor receptor superfamily, was examined in 40 esophagogastrectomy specimens containing areas of Barrett esophagus (n = 27), low-grade dysplasia (n = 27), high-grade dysplasia or carcinoma in situ (n = 22), and esophageal adenocarcinoma (EAC; n = 28) with immunohistochemical analysis. The results revealed significantly more overexpression of DcR3 in high-grade dysplasia or carcinoma in situ and EAC than in benign esophageal mucosa (both P < .0001), Barrett esophagus (both P < .001), and low-grade dysplasia (P < .01 and P = .033, respectively). Low-grade dysplasia also showed significant overexpression of DcR3 compared with benign esophagus (P < .05) but not with Barrett esophagus (P > .05). DcR3 overexpression seems to negatively correlate with the grade of EAC. Our results suggest that overexpression of DcR3 protein might aid in the diagnosis of high-grade dysplasia or carcinoma in situ and EAC and also might serve as a potential therapeutic target.  相似文献   
80.
Osteosarcomatosis   总被引:10,自引:0,他引:10  
A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.  相似文献   
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