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1.
目的建立一种基于规律成簇的间隔短回文重复序列及其相关蛋白(CRISPR/Cas13a)的乙型肝炎病毒(HBV)共价闭合环状DNA(HBV cccDNA)检测方法。方法提取2017年6月至2020年10月于首都医科大学附属北京佑安医院就诊的4例乙型肝炎患者肝脏总DNA后,使用HindⅢ内切酶和质粒安全性ATP依赖DNA酶(PSAD)分别进行酶切;根据松弛环状DNA(rcDNA)和cccDNA的结构差异,设计特异性扩增HBV cccDNA的引物,对酶切后的产物进行滚环扩增(RCA)和PCR扩增;并筛选crRNA,建立基于CRISPR/Cas13a技术的HBV cccDNA检测新方法。结果利用α-1-抗胰蛋白酶(A1AT)和HBV表面抗原(HBsAg)引物对双重酶切后的产物进行扩增,验证产物中HBV基因组的存在;利用HBV cccDNA和HBV rcDNA引物对PSDA酶切后的产物扩增,验证了产物中只存在HBV cccDNA;利用RCA后的阳性样本作为模板梯度稀释,然后进行PCR扩增转录后使用CRISPR/Cas13a检测,计算出检测下限为10拷贝/μl。结论本研究建立了RCA-PCR-CRISPR-Cas13a的新型检测方法,可对HBV cccDNA进行高灵敏度和高特异性检测,为乙型肝炎患者抗病毒治疗评估、治疗终点的确定以及调整治疗方案提供了有效的监测手段。  相似文献   
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PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences.  相似文献   
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沈晓敏  姚芳园  沈贤新  黄婷  徐璟  郑芸 《新中医》2021,53(5):175-178
目的:研究儿童生长贴联合艾灸、运动操及饮食习惯调整相结合的方式对儿童身高改善的影响。方法:纳入身高偏矮患儿58例为研究对象,随机分为研究组(儿童生长贴联合艾灸、运动操与饮食习惯调整)与对照组(饮食指导)各29例,比较血清指标、身高增值与生长速度、有效率与不良反应。结果:2组干预3个月的身高增值与生长速度比较,差异无统计学意义(P>0.05);干预6个月后与对照组比较,研究组身高增值与生长速度高(P<0.05)。2组干预前胰岛素样生长因子-1 (IGF-1)与胰岛素样生长因子结合蛋白-3 (IGFBP-3)水平比较,差异无统计学意义(P>0.05);干预后与对照组比较,研究组IGF-1与IGFBP-3水平均更高(P<0.05)。对照组总有效率为79.31%,研究组为96.55%,2组比较,差异有统计学意义(P<0.05)。与对照组比较,研究组甲状腺素低下、水肿与头疼的不良反应发生率均更低(P<0.05)。结论:对身高偏矮患儿采用儿童生长贴联合艾灸、运动操及饮食习惯调整相结合的方式治疗能提高身高增值与生长速度,提高疗效并减少不良反应发生,安全性高。  相似文献   
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IntroductionThe prevalence of the phylogenetic groups of Mycobacterium tuberculosis Beijing genotype has been reported to be similar in different areas of Japan. However, recent reports from rural areas of Japan show a low prevalence of modern Beijing strains, suggesting that the distribution of modern Beijing strains may have changed recently. Therefore, multi-locus variable number of tandem repeats analysis (MLVA) and draft whole genome sequence (DWGS) analysis were carried out to investigate the prevalence of particular genotype strains.MethodsNine hundred and ninety modern Beijing strains were studied using minimum spanning tree (MST) analysis and neighbor-net analysis of MLVA and WGS data.ResultsAn MST of M. tuberculosis Beijing genotype strains reconstructed from 12 loci-MLVA data showed two large complexes with the J12-0006 MLVA pattern. In one of the complexes, strains with the pECT07 pattern produced by 24 loci-MLVA and its SLVs were most prevalent. DWGS analysis was carried out for pECT07 and its SLV strains. Neighbor-net and MST analyses of the DWGS data showed that pECT07 and its SLV strains were grouped in separate clusters. When all the combinations of two of the tested strains were analyzed, MST analysis showed that only 9 (1.7%) of the 528 pairs of tested strains had 5 or less SNPs.ConclusionsThe results of this study suggested that pECT07 and its variants were prevalent among M. tuberculosis modern Beijing strains in Chiba Prefecture, but the prevalence of those strains may not have been due to an earlier large-scale latent outbreak.  相似文献   
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【目的】利用高通量测序技术获得大青的转录组信息特征。【方法】通过高通量测序平台Illumina HiSeq;2500对大青进行转录组测序,采用Trinity软件de novo组装获得Unigene,并基于序列同源性对Unigene进行功能注释,得到大青转录组的遗传信息。【结果】测序数据经过质控后共获得26 394 223个高质量的Reads,通过de novo组装获得100 191个Unigene,N50长度为1 055 bp,平均长度724.4 bp。其中59 690个(59.58%)Unigene在NR、SwissProt、KOG、GO、KEGG数据库中均得到注释。其中KEGG数据库注释到38 260个Unigene,涉及136条代谢通路。在大青转录组中共鉴定到407个Unigene参与萜类化合物的生物合成,165个Unigene涉及类黄酮生物合成,29个Unigene参与黄酮和黄酮醇生物合成,37个Unigene参与异黄酮生物合成,同时,还鉴定到210类转录因子。MISA分析发现6 680个Unigene包含8 640个简单重复序列。【结论】利用高通量测序技术和生物信息分析获得了大青的转录组信息特征,这些数据可为后期开展功能基因鉴定、解析黄酮类化合物次生代谢途径及其调控机制奠定研究基础。  相似文献   
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摘要:目的研究 1例Melnick-Needles综合征家系的致病基因并为该家系提供遗传咨询依据。方法采集先证者即 1例不明原因骨骼发育异常、身材矮小的青年女性患者及其父母外周血标本,提取基因组DNA,采用家系全外显子组测序(Trio-WES)筛查先证者致病基因及突变位点,并通过Sanger测序进行验证。结果先证者位于 X染色体上的FLNA基因有一杂合变异位点:NM_ 001 110556.2: c.3562G>A(p.A1188T),父母均为野生型。根据ACMG指南,提示FLNA基因的c.3562G>A突变为1个致病突变位点,与X连锁显性遗传疾病Melnick-Needles综合征相关。国内未见该致病位点报道。结论确诊1 例罕见Melnick-Needles综合征,致病FLNA突变c.3562G>A在国内为首次报道,为患者及家属遺传咨询提供了依据。  相似文献   
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The objective of this mini‐review is to provide insights on the advances in the understanding of the genetic variants associated with different manifestations of Hirschsprung disease, which may present with a range of denervation from a short segment of colon to total colonic and small bowel or extensive aganglionosis. A recent article in this journal documented potential gene variants involved in long‐segment Hirschsprung disease in 23 patients. Gene variants were identified using a 31‐gene panel of genes related to Hirschsprung disease or enteric neural crest cell development, as previously reported in the literature. The study identified potentially harmful variants in eight genes across 13 patients, with a detection rate of 56.5% (13/23 patients). Five patients had pathologic variants in RET, NRG1, and L1CAM, and the remainder were considered variants of unknown significance. The authors attempted prenatal diagnosis of Hirschsprung disease utilizing an amniocentesis sample obtained for advanced maternal age in a family with a known deleterious RET mutation, manifested in the father (long‐segment Hirschsprung disease) and older daughter (total colonic aganglionosis). The fetus had the same RET variant but, after several years of follow‐up, has not developed any symptoms of Hirschsprung disease, supporting the conclusion that this RET mutation is an autosomal dominant gene with incomplete penetrance. This experience suggests that genetic counseling is appropriate to carefully assess the justification of prenatal testing, especially, when the phenotype of long‐segment Hirschsprung disease is so variable and the disease is potentially curable with surgery.  相似文献   
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Background: We determined qualitative and quantitative serum unconjugated bile acid (SUBA) levels among children with history of intestinal failure (IF) and suspected small bowel bacterial overgrowth (SBBO). Methods: This was a single‐center, case‐control pilot study conducted at Cincinnati Children's Hospital Medical Center. Children with history of IF and suspected SBBO were enrolled as subjects. Age‐matched children without IF or suspected SBBO served as controls. All participants underwent small bowel fluid sampling for microbial culture analysis. Additionally, serum fractionated and total bile acids were measured by liquid chromatography‐mass spectrometry at enrollment and following treatment for SBBO. Results: SUBA concentrations were elevated in IF subjects (median 1.16 μM, range 0.43–10.65 μM) compared with controls (median 0.10 μM, range 0.05–0.18 μM, P = 0.001). Among SUBA, chenodeoxycholic acid (CDCA) was significantly elevated in subjects (median 0.8 μM, range 0–7.08 μM) compared with controls (median 0 μM, range 0–0.03 μM, P = 0.012). When controls were excluded from analysis, IF subjects with positive aspirates for SBBO demonstrated higher concentration of CDCA (median 7.36 μM, range 1.1–8.28 μM) compared with IF subjects with negative aspirates (median 0.18 μM, range 0–1.06 μM, P = 0.017). Treatment for SBBO did not alter SUBA concentration. Conclusions: SUBA concentrations are elevated in children with history of IF and presumed SBBO compared with non‐IF controls. CDCA was more prevalent in IF subjects with positive aspirates for SBBO compared with IF subjects with negative aspirates. The determination of SUBA concentration may be a useful surrogate to small bowel fluid aspiration in the diagnosis of SBBO in children with history of IF.  相似文献   
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