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991.
992.
Jingting Li Yong Du Ji Qi Ravikumar Sneha Anthony Chang Chandra Mohan Wei‐Chuan Shih 《Journal of biophotonics》2016,9(3):260-269
Both acute nephritis and chronic nephritis account for substantial morbidity and mortality worldwide, partly due to the lack of reliable tools for detecting disease early and monitoring its progression non‐invasively. In this work, Raman spectroscopy coupled with multivariate analysis are employed for the first time to study the accelerated progression of nephritis in anti‐GBM mouse model. Preliminary results show up to 98% discriminant accuracy for the severe and midly diseased and the healthy among two strains of mice with different susceptibility to acute glomerulonephritis. This technique has the potential for non‐invasive or minimally‐invasive early diagnosis, prognosis, and monitoring of renal disease progression.
993.
核酸适配体是一类通过指数富集的配体系统进化(SELEX)技术获得的具有独特三维构象的小分子RNA 或单链DNA。核酸适
配体能高亲和力和高特异性与靶点结合,同时具有自身分子质量小、免疫原性低、热/化学稳定性高、靶标分子范围广等特点,广泛应用
于疾病诊断、治疗、生物传感器、生物标志物筛选、新药研发等领域。综述近年来核酸适配体在肿瘤诊断和治疗方面的应用,并对核酸
适配体的临床研究现状、市场前景及面临挑战和发展趋势作简要分析。 相似文献
994.
Glass IA Rauen KA Chen E Parkes J Alberston DG Pinkel D Cotter PD 《Human genetics》2006,118(5):611-617
Ring chromosome 15 [r(15)] is an uncommon finding with less than 50 patients reported. Precise genotype–phenotype correlations
are problematic because of the difficulties in determining the extent of euchromatic loss, the level of mosaicism, and the
influence of the timing of ascertainment. We report two discordant examples of r(15) patients. In the first case, prenatal
diagnosis of a de novo r(15) was made during the second trimester: mos 46,XX,r(15)(p11.2q26)[32]/45,XX,-15[13]/47,XX,r(15)(p11.2q26)x2[3]/46,XX,dic
r(15)(p11.2q26p11.2q26[1]/46,XX[2]. Postnatal follow-up revealed extremely small stature, heart defects, and developmental
delay. Patient 2 was a 31-year-old short-statured female who was living independently: 46,XX,r(15)(p11q26). Both cases showed
loss of the 15q subtelomeric region by fluorescence in situ hybridization (FISH). To investigate the discordance in phenotypes
between the two patients, we undertook array comparative genomic hybridization (array CGH) analyses to more fully characterize
the deletions associated with these otherwise structurally indistinguishable r(15) chromosomes from conventional cytogenetic
analyses and fluorescence in situ hybridization (FISH) studies. By array CGH, patient 1 showed deletion of multiple contiguous
clones predicting an approximately 6 Mb deletion of distal 15q. In contrast, patient 2 showed loss of just the 15q subtelomeric
clone and an interstitial clone by array CGH confirming that the severity of the phenotype correlated with the size of the
deletion at the molecular level. These cases illustrate the utility of array CGH characterization for determining the size
of the associated deletion in ring chromosomes and for facilitating phenotype–genotype correlations. 相似文献
995.
The IS6110 belongs to the family of insertion sequences (IS) of the IS3 category. This insertion sequence was reported to be specific for Mycobacterium tuberculosis complex and hence is extensively exploited for laboratory detection of the agent of tuberculosis and for epidemiological investigations based on polymerase chain reaction. IS6110 is 1361-bp long and within this sequence different regions have been utilized as targets in the identification of M. tuberculosis by PCR. However, the results are not always consistent, specific and sensitive. In recent years, a few clinical investigations raised concerns over IS6110 specificity and sensitivity in the diagnosis of tuberculosis due to false-positive (homology with other target DNA besides M. tuberculosis) or false negative (due to absence of copies of IS6110) results with IS6110 specific primers. To unravel the variations in IS6110 sequences, an insilico analysis of IS6110 sequence of different strains of M. tuberculosis was carried out. Our results of comparative analysis of IS6110 insertion sequences of M. tuberculosis complex suggests that, IS6110 insertion sequences harbored variations in its sequence, which is evident from the phylogenetic analysis. Importantly, IS6110 sequence has divergence within the copies of same strain and formed different clusters. A list of IS6110 specific primers used in various clinical investigation of tuberculosis was obtained from the literature and their performance scrutinized. Our study emphasizes the need to develop PCR assays (multiplex format) targeting more than one region of the genome of M. tuberculosis. 相似文献
996.
997.
胸膜肺炎放线杆菌基因分型方法的建立及其临床应用 总被引:4,自引:2,他引:4
根据胸膜肺炎放线杆菌各血清型之间外毒素(Apx),外膜脂蛋白(OmlA),转铁蛋白B(TbpB)的基因差异,分别对各血清型进行PCR扩增,得到不同的特异性片段,可区分开生物Ⅰ型13个标准菌株血清型中的8个血清型。临床检测结果与血清学分型一致,将此分型系统用于临床送检的126份肺脏和42份扁桃体的病原学检测,可直接检测出胸膜肺炎放线杆菌感染。此方法还可以将一些尚未定型的菌株进行归类,弥补了血清学方法的不足,为细菌的流行病学调查提供了可靠的技术手段。 相似文献
998.
伪狂犬病病毒gE基因主要抗原表位区的原核表达及其在疫苗接种和自然感染鉴别诊断中的应用 总被引:4,自引:0,他引:4
根据伪狂犬病病毒(PRV)Min-A株gE基因序列,利用PCR方法扩增了PRV-gE基因不含信号肽、胞内区和跨膜区的主要抗原表位区,并克隆到原核表达载体pGEX-6p-1中,获得的重组质粒命名为pGEX-tgE。经SDSPAGE电泳分析证实克隆的部分gE基因获得了表达,融合表达产物大小约为63kD,并在终浓度为0.6mmol/L的IPTG诱导下,3.5h其表达量达到高峰。通过改变诱导条件,有效抑制了包涵体形成,提高了重组蛋白的溶解性。Western blot分析证实表达的重组gE蛋白具有抗原反应活性。将表达产物利用亲和层析法纯化后作为ELISA抗原,通过对其特异性、敏感性及工作条件的优化试验,和对48份PRV阴性血清样品的检测结果的统计学分析,建立了猪伪狂犬病tgE-ELISA鉴别诊断方法。通过对400份送检血清样品的检测结果分析,表明其与PRV全病毒ELISA试验的符合率高达95%以上,与基于抗gE蛋白单抗竞争性ELISA的符合率达94%。此方法可用于gE基因缺失PRV疫苗免疫动物和PRV自然感染动物的鉴别诊断。 相似文献
999.
Spirotontonia grandis (Suzuki and Han, 2000) Agatha, 2004 belongs to the family Tontoniidae Agatha, 2004 because it has a contractile tail. It is the type of the genus Spirotontonia Agatha, 2004, which is characterized by a sinistrally spiralled girdle kinety. Supplementary observations on protargol-impregnated and, especially, live specimens of S. grandis from the Irish Sea are provided. These new findings are included in an improved species diagnosis. Furthermore, they contribute to a better separation of the tontoniid S. grandis from the strombidiid Laboea strobila, which also has a screw-like appearance, a sinistrally spiralled girdle kinety, and multiple macronuclear nodules, but lacks the tontoniid tail. Since the tail of S. grandis, the main distinguishing feature between the two species, is highly contractile and easily lost, further differences are emphasized, e.g., the lower number of girdle kinety whorls (3.0–3.5 vs. 4.5–5.0), the larger cell size (110–170×55–80 μm vs. 80–110×40–60 μm after protargol impregnation), the relatively larger size of the ventral portion of the membranellar zone (51% vs. 40% of body length), and the overlapping cortical platelets (present vs. absent). The record of S. grandis from the Irish Sea is the first record outside the East China Sea and the second worldwide. 相似文献
1000.
The aims of this study were to describe the distribution of magnesium (Mg) and its retranslocation within wheat, in order to develop diagnostic procedures for Mg deficiency. Plants were grown in solution culture with both constant supply (0, 5, 10, 20, 40, 80, 160 MMg) and discontinued supply (40 M and 160 M decreased to nil).Magnesium was depleted from old leaves when Mg supply to the roots was halted. However, initial deficiency symptoms occurred on young leaves under constant but inadequate supply, contrasting with previous reports. Magnesium concentrations were also lower in young leaves compared to old leaves. Symptoms of yellowing and necrosis occurred if the leaf tissue contained <1194 gg–1, irrespective of leaf age. The minimum Mg concentration in whole shoots associated with maximum shoot weight was 932 gg–1; for the youngest emerged blade (YEB) it was 861 gg–1. Symptoms were apparent on the young leaf before a reduction in shoot weight was measurable. The concentration of Mg in the YEB and whole shoot were better related to solution Mg concentration than was the Mg concentration in the old leaf. 相似文献