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91.
Jennifer E. Sanner Lorraine Frazier Malini Udtha 《The Yale journal of biology and medicine》2013,86(1):5-13
Platelet serotonin has been associated with depression and coronary artery
disease. Understanding the association between platelet serotonin and depressive
symptoms during acute coronary syndrome (ACS) may explain some of the ACS events
seen in depressed individuals. The objectives were to evaluate whether levels of
platelet serotonin during an ACS event differ between individuals who screen
positive or negative for depressive symptoms and to determine if a linear
relationship exists. In this cross-sectional study, data were collected on 51
patients with ACS. Multiple linear regression models were examined. Platelet
serotonin levels were not significantly different between the depressed and
non-depressed groups (β = -4.093 and p = .293); a linear relationship was not
found (β = -.254 and p = .250). In conclusion, a relationship between platelet
serotonin and depressive symptoms was not found. It remains unclear if an
association exists between platelet serotonin levels and depressive symptoms
during hospitalization for ACS. 相似文献
92.
Ginger R. Zipperer Sridhar Arumugam Sharon R. Chirgwin Sharon U. Coleman Krishna P. Shakya Thomas R. Klei 《Experimental parasitology》2013
Previous studies have shown that intradermally (ID) injected Brugia pahangi L3s migrate through various tissues and into the lymphatics of gerbils in a distinct pattern. Excretory/secretory products (ES) produced at the time of invasion of B. pahangi are likely to be important in this early migration phase of the parasite life cycle in their rodent host. Hence, early L3 ES was collected from 24 h in vitro cultures of B. pahangi L3 larvae and used in immunization experiments to investigate the effect of immunity to early L3 ES on worm migration, survival and development of B. pahangi. Immunization of gerbils with ES in RIBI adjuvant produced antibodies to numerous ES proteins eliciting a strong humoral response to ES and indirect fluorescent antibody (IFA) assay using anti-ES serum recognized the ES proteins on the surface of B. pahangi L3 larvae. Following ES immunization, gerbils were challenged either ID or intraperitoneally (IP) with 100 L3s of B. pahangi and euthanized at 3 or 106 days post inoculation (DPI). Immunization with early ES slowed the migration of ID inoculated L3 at 3 DPI and significantly altered the locations of adult worms at 106 DPI. Immunization did not induce protection in any treatment group. However, immunized animals had significantly fewer microfilariae per female worm suggesting the antigens in ES are important in microfilariae development or survival in the host. The number of lymphatic granulomas was also significantly reduced in ES immunized animals. It is important to note that microfilariae serve as a nidus in these granulomas. Our results shows immunization with early Brugia malayi L3 ES alters the worm migration, affects circulating microfilarial numbers and reduces lymphatic granulomas associated with B. pahangi infection in gerbils. 相似文献
93.
Monika Primon Peter C. Huszthy Helena Motaln Krishna M. Talasila Ana Torkar Rolf Bjerkvig Tamara Lah Turnšek 《Experimental cell research》2013
Despite improved treatment options, glioblastoma multiforme (GBM) remains the most aggressive brain tumour with the shortest post-diagnostic survival. Arsenite (As2O3) is already being used in the treatment of acute promyelocytic leukaemia (APL), yet its effects on GBM have not been evaluated in detail. In U87MG cell monolayers, we have previously shown that arsenite cytotoxicity significantly increases upon transient inhibition of lysosomal protease Cathepsin L (CatL). As multicellular spheroids more closely represent in vivo tumours, we aimed to evaluate the impact of permanent CatL silencing on arsenite treatment in U87MG spheroids. CatL was stably silenced using shRNA expression plasmid packed lentiviruses. By using metabolic- and cell viability assays, we demonstrated that long-term CatL silencing significantly increased arsenite cytotoxicity in U87MG spheroids. Silenced CatL also increased arsenite-mediated apoptosis in spheroids via elevated p53 expression, Bax/Bcl2 ratio and caspase 3/7 activity, though with lower efficacy than in monolayers. Arsenite cytotoxicity was enhanced by lower CatL activity, since similar cytotoxicity increase was also observed using the novel CatL inhibitor AT094. The results have significant translational impact, since stable CatL silencing would enable the application of lower systemic doses of arsenite to achieve the desired cytotoxic effects on GBMs in vivo. 相似文献
94.
Pin Guo Quanmin Nie Jin Lan Jianwei Ge Yongming Qiu Qing Mao 《Biochemical and biophysical research communications》2013
The c-Myc oncogene is amplified in many tumor types. It is an important regulator of cell proliferation and has been linked to altered miRNA expression, suggesting that c-Myc-regulated miRNAs might contribute to tumor progression. Although miR-26a has been reported to be upregulated in glioblastoma multiforme (GBM), the mechanism has not been established. We have shown that ectopic expression of miR-26a influenced cell proliferation by targeting PTEN, a tumor suppressor gene that is inactivated in many common malignancies, including GBM. Our findings suggest that c-Myc modulates genes associated with oncogenesis in GBM through deregulation of miRNAs via the c-Myc–miR-26a–PTEN signaling pathway. This may be of clinical relevance. 相似文献
95.
Luca Federici Brunangelo Falini 《Protein science : a publication of the Protein Society》2013,22(5):545-556
Nucleophosmin (NPM1) is an abundant, ubiquitously expressed protein mainly localized at nucleoli but continuously shuttling between nucleus and cytoplasm. NPM1 plays a role in several cellular functions, including ribosome biogenesis and export, centrosome duplication, chromatin remodeling, DNA repair, and response to stress stimuli. Much of the interest in this protein arises from its relevance in human malignancies. NPM1 is frequently overexpressed in solid tumors and is the target of several chromosomal translocations in hematologic neoplasms. Notably, NPM1 has been characterized as the most frequently mutated gene in acute myeloid leukemia (AML). Mutations alter the C‐terminal DNA‐binding domain of the protein and result in its aberrant nuclear export and stable cytosolic localization. In this review, we focus on the leukemia‐associated NPM1 C‐terminal domain and describe its structure, function, and the effect exerted by leukemic mutations. Finally, we discuss the possibility to target NPM1 for the treatment of cancer and, in particular, of AML patients with mutated NPM1 gene. 相似文献
96.
本文观察了番茄叶水提物对小鼠的急性毒性及其对脂多糖诱导急性炎症模型大鼠的影响。采用经典的急性毒性试验方法,观察小鼠口服给予番茄叶水提物的死亡率,按寇氏法计算半数致死量(LD50)。50只SD大鼠随机分为正常组、模型组、阳性药泼尼松5 mg/kg组与番茄叶水提物3.19、1.59 g/kg组,连续给药10 d,每天一次。以腹腔注射脂多糖(LPS)建立急性炎症模型,ELISA法测定血清白细胞介素1(IL-1)、白细胞介素6(IL-6)、肿瘤坏死因子(TNF-α)。结果显示,番茄叶水提物单次灌胃给药的LD50为46.44g/kg,95%可信限为39.52~54.60 g/kg。3.19 g/kg番茄叶水提物可明显降低LPS诱导的急性炎症小鼠血清IL-1、IL-6和TNF-α水平。番茄叶水提物抑制LPS诱导急性炎症的作用机制可能与其降低血清炎症因子水平有关。 相似文献
97.
Yoshichika Takamura Tomiko Takamura Masami Soejima Teijiro Uemura 《Bioscience, biotechnology, and biochemistry》2013,77(5):718-728
Maleate cis-trans isomerase in Alcaligenes faecalis IB–14 was induced by malonate and purified about 100-fold over the crude cell-free extract by treatments of ammonium sulfate fractionation, Sephadex G–100 gel filtration, DEAE-cellulose and DEAE-Sephadex A–50 column chromatography. The preparation was shown to be monodisperse on ultracentrifugal analysis and Svedberg value was found to be 3.84 S.The enzyme was most active at pH value around 8.3 and was stable over the range of pH 5.0 to 7.0 in the presence of dithiothreitol (DTT) for a few weeks, but in the absence of it, the enzyme activity was markedly decreased, especially in the alkaline region. The enzyme activity was inhibited by various sulfhydryl reagents and oxidizing agents, whereas it was not affected by metal chelating agents. The inhibition by Hg2+ and PCMB was overcome by the addition of sulfhydryl compounds such as DTT, 2-mercaptoethanol, l-cysteine and glutathione. It was observed that the enzyme did not require co-factor for its function.Kinetic studies showed that Michaelis constant for maleate was 2.8×10?3 m and the enzyme did not catalyze the reverse reaction. 相似文献
98.
目的 研究小儿腹泻病继发乳糖不耐受的年龄、病因及乳糖酶治疗继发乳糖不耐受的效果.方法 对382例腹泻继发乳糖不耐受患儿进行年龄、病因分析,同时将患儿分成治疗及对照两组,分析乳糖酶的疗效.结果 小儿腹泻继发乳糖不耐受以婴幼儿多见,轮状病毒感染是继发乳糖不耐受的主要病因,乳糖酶治疗继发乳糖不耐受疗效显著.结论 婴幼儿腹泻常规给予乳糖酶可以缩短病程,减少治疗费用,患儿及家长易于接受. 相似文献
99.
100.
目的:探究舒芬太尼与曲马多对用于小儿鼾症手术苏醒期躁动的作用与影响。方法:60例ASAI或II级扁桃体肥大或腺样体肥大的鼾症手术患儿,年龄6-14岁,无呼吸系统,循环系统等疾病,一般状态良好。随机分为舒芬太尼组(s组)和曲马多(T组),每组各30例。常规监测各项生命体征。于手术结束前20分钟(min),S组缓慢静脉输入0.15μg/kg舒芬太尼,T组静脉输入1.2mg/kg曲马多。观察各组的:平均动脉压 (MAP)、心率(HR)、血氧饱和度(SpO2),进行各组的镇静评分(RSS)、躁动评分(RS)、镇痛评分(VRS)、意识状态评分(OAAS)。记录拔管前(T0)、拔管时(T1)、拔管后5min(T2)、拔管后10min(T3)、拔管后20min(T4)各时间点各参数的变化。记录各组的恶心呕吐、呼吸抑制、烦躁等的发生率。结果:SpO2各组间无显著差异。MAP,HR在各时间点的变化T组大于S组,P〈0.05,有显著差异。T组在RS,RSS,VRS评分与S组有显著差异,P〈0.05。结论:0.15μg/kg的舒芬太尼在小儿鼾症手术的苏醒期可以维持稳定的血流动力学,副作用小,镇痛效果良好,可以有效减少小儿苏醒期的躁动。 相似文献