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931.
932.
刘伟  张倩倩  舒芳  蔡英丽  马晓龙  边银丙 《菌物学报》2019,38(12):2195-2204
基于梯棱羊肚菌Morchella importuna两个子囊孢子培养物的全基因组测序数据,对全基因组范围内的变异位点进行分析。共鉴定到18 438个变异位点,平均每Mbp的变异位点数量为361个;变异位点以单核苷酸多态性SNP为主,共计17 104个,基因组中SNP的频率为335SNPs/Mbp;Indel多态性位点1 334个,以2-10bp的插入缺失为主;73.4% SNP/Indel位于基因间隔区域,外显子区域共检测到3 042个变异位点,占总数的16.50%;对基因功能产生确定影响的移码突变有1 088个,占5.90%,错义突变916个,占比4.97%;不同Scaffold上的SNP/Indel出现频率不同,SNP频率最大的为Scaffold80,平均每Mbp包含2 856个SNP,频率最低为Scaffold60和Scaffold75,分别为16SNPs/Mbp和30SNPs/Mbp;对≥11bp的Indel变异位点进行标记开发和多态性群体分析,成功开发出75对Indel标记。采用原生质体单细胞分离技术,获得了梯棱羊肚菌M04的两个可亲和的同核体菌株M04P01和M04P40,同时采用来自M04子囊果的58个单孢菌株作为作图群体,初步构建了包含75个Indel标记和1个交配型基因的梯棱羊肚菌遗传连锁图谱,共获得12个连锁群,连锁群总长度273.7cM。  相似文献   
933.
喀斯特石漠化环境有着高度的生境异质性,异质性生境中土被不连续,土壤瘠薄,岩溶漏斗上的土壤保水性差,严重制约着喀斯特植被的生长及分布。为探究克隆植物在喀斯特地区的适应策略,本研究以喀斯特黄色石灰土为基质,选用克隆植物活血丹(Glechoma longituba),以一个节间连接的两个分株为材料,保持节间连接或切断,种植于相邻花盆中,并施以不同浇水量,以明确不同水分可用性水平下克隆整合对活血丹生物量积累、生物量分配、叶片气孔及叶片组织特征的影响。结果显示,克隆整合显著促进活血丹生物量的积累及对根、叶的生物量分配;增加了活血丹叶气孔导度,降低了气孔指数;叶海绵组织受克隆整合影响较小,但栅栏组织及栅海比(栅栏组织/海绵组织)表现为非整合分株高于整合分株。本研究表明,克隆整合可增加活血丹胁迫分株对根、叶的投资,并以更佳的叶气孔、组织适应策略提高其在喀斯特生境中的生存与适应。  相似文献   
934.
目的:探讨复方丹参注射液联合阿奇霉素治疗小儿喘息性支气管炎的效果及对炎性因子的影响。方法:选取2015年6月~2018年6月我院收治的喘息性支气管炎患儿300例,采用随机数字表法将患儿分为两组,每组各150例。对照组在常规治疗的基础上给予阿奇霉素注射液治疗,观察组在对照组的基础上联合应用复方丹参注射液治疗。比较两组的临床治疗效果,临床症状缓解时间及住院时间,治疗前后两组血清白介素(Interleukin, IL)-6、IL-8和肿瘤坏死因子-α(Tumor necrosis factor-α, TNF-α)水平的变化情况及不良反应发生情况和复发率。结果:治疗后,观察组治疗总有效率显著高于对照组(93.33%VS.85.33%, P0.05);观察组喘息缓解时间、咳嗽缓解时间、哮鸣音消失时间、体温恢复时间及住院时间均显著短于对照组(P0.05);两组治疗后血清IL-6、IL-8和TNF-α水平均较治疗前显著下降,且观察组更低(P0.05);两组不良反应发生率比较差异无统计学意义(P0.05),观察组的复发率显著低于对照组(P0.05)。结论:复方丹参注射液联合阿奇霉素可快速缓解喘息性支气管炎患儿的临床症状、体征并缩短住院时间,提高临床治疗效果,且复发率低,安全性较高,这可能与其可显著降低患儿血清IL-6、IL-8和TNF-α水平有关。  相似文献   
935.
为了快速高效的观察兰科植物铁皮石斛的显微结构,利用光镜和改进的蔗糖保护--液氮速冻冰冻切片法,观察铁皮石斛根、茎、叶的显微结构。该技术方法是将铁皮石斛器官经过蔗糖磷酸缓冲液保护液处理后抽真空,再经过液氮速冻、包埋、切片、展片观察、染色以及拍照等步骤,制作出铁皮石斛根、茎和叶较完整的显微结构切片。研究结果表明,适合铁皮石斛根的最适条件为:蔗糖质量体积分数为8%、冷凝温度-25℃、切片厚度20μm;茎的最适条件为:蔗糖质量体积分数为16%、冷凝温度-20℃、切片厚度15μm;叶的最适条件为:蔗糖质量体积分数为4%、冷凝温度-20℃、切片厚度10μm。该研究在兰科植物显微结构观察和组织化学研究中将具有广阔的应用前景。  相似文献   
936.
937.
Interleukin‐29 (IL‐29) is a newly discovered member of type III interferon. It mediates signal transduction via binding to its receptor complex and activates downstream signalling pathways, and therefore induces the generation of inflammatory components. Recent studies reported that expression of IL‐29 is dysregulated in inflammatory autoimmune diseases, such as rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, Sjögren's syndrome, psoriasis and systemic sclerosis. Furthermore, functional analysis revealed that IL‐29 may involve in the pathogenesis of the inflammatory autoimmune disorders. In this review, we will systematically review the current knowledge about IL‐29. The information collected revealed the regulatory role of IL‐29 and may give important implications for its potential in clinical treatment.  相似文献   
938.
Uveal melanoma (UM) has a high mortality rate due to liver metastasis. The insulin‐like growth factor‐1 receptor (IGF‐1R) is highly expressed in UM and has been shown to be associated with hepatic metastases. Targeting IGF signalling may be considered as a promising approach to inhibit the process of metastatic UM cells. Pristimerin (PRI) has been demonstrated to inhibit the growth of several cancer cells, but its role and underlying mechanisms in the IGF‐1‐induced UM cell proliferation are largely unknown. The present study examined the anti‐proliferative effect of PRI on UM cells and its possible role in IGF‐1R signalling transduction. MTT and clonogenic assays were used to determine the role of PRI in the proliferation of UM cells. Flow cytometry was performed to detect the effect of PRI on the cell cycle distribution of UM cells. Western blotting was carried out to assess the effects of PRI and IGF‐1 on the IGF‐1R phosphorylation and its downstream targets. The results indicated that IGF‐1 promoted the UM cell proliferation and improved the level of IGF‐1R phosphorylation, whereas PRI attenuated the effect of IGF‐1. Interestingly, PRI could not only induce the G1 phase accumulation and reduce the G2 phase induced by IGF‐1, but also could stimulate the expression of p21 and inhibit the expression of cyclin D1. Besides, PRI could attenuate the phosphorylations of Akt, mTOR and ERK1/2 induced by IGF‐1. Furthermore, the molecular docking study also demonstrated that PRI had potential inhibitory effects on IGF‐1R. Taken together, these results indicated that PRI could inhibit the proliferation of UM cells through down‐regulation of phosphorylated IGF‐1R and its downstream signalling.  相似文献   
939.
Diabetic cardiomyopathy (DCM) is a condition associated with significant structural changes including cardiac tissue necrosis, localized fibrosis, and cardiomyocyte hypertrophy. This study sought to assess whether and how FBXL10 can attenuate DCM using a rat streptozotocin (STZ)‐induced DCM model system. In the current study, we found that FBXL10 expression was significantly decreased in diabetic rat hearts. FBXL10 protected cells from high glucose (HG)‐induced inflammation, oxidative stress, and apoptosis in vitro. In addition, FBXL10 significantly activated PKC β2 signaling pathway in H9c2 cells and rat model. The cardiomyocyte‐specific overexpression of FBXL10 at 12 weeks after the initial STZ administration attenuated oxidative stress and inflammation, thereby reducing cardiomyocyte death and preserving cardiac function in these animals. Moreover, FBXL10 protected against DCM via activation of the PKC β2 pathway. In conclusion, FBXL has the therapeutic potential for the treatment of DCM.  相似文献   
940.
Interleukin‐27 (IL‐27) gene polymorphisms are linked to infectious disease susceptibility and IL‐27 plasma level is associated with HIV infection. Therefore, we aimed to investigate the association between IL‐27 polymorphisms and susceptibility to HIV infection and disease progression. A total of 300 patients with HIV infection (48 long‐term nonprogressors and 252 typical progressors) and 300 healthy controls were genotyped for three IL‐27 polymorphisms, rs17855750, rs181206, rs40837 which were performed by using multiple single nucleotide primer extension technique. Significant association was found between IL‐27 rs40837 polymorphisms with susceptibility to HIV infection (AG vs AA: adjusted OR = 1.60, 95% CI, 1.11‐2.30, = 0.012; AG+GG vs AA: adjusted OR = 1.44, 95% CI, 1.02‐2.03, P = 0.038) and disease progression (LTNP: AG vs AA: adjusted OR = 2.33, 95% CI, 1.13‐4.80, P = 0.021; TP: AG vs AA: adjusted OR = 1.50, 95% CI, 1.04‐2.24, P = 0.030). Serum IL‐27 levels were significantly lower in cases compared to controls (< 0.001). There were lower serum IL‐27 levels in TPs than in LTNPs (< 0.001). We further found that LTNPs with rs40837 AG or GG genotype had lower serum IL‐27 levels than with AA genotype (< 0.05). The CD4+T counts in cases were significantly lower than controls (< 0.001). In contrast, individuals with rs40837 AG genotype had lower CD4+T counts than with AA genotype in cases (< 0.05). In addition, CD4+T counts in TPs were significantly lower than LTNPs (< 0.001). IL‐27 rs40837 polymorphism might influence the susceptibility to HIV infection and disease progression probably by regulating the level of serum IL‐27 or the quantity of CD4+T.  相似文献   
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