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111.
【目的】初步探讨与单纯疱疹病毒糖蛋白D竞争结合疱疹病毒侵入介体的淋巴毒素类似物(lymphotoxin-like inducible protein that competes with glycoprotein D for herpesvirus entry on T cells,LIGHT)在抗衣原体感染免疫及介导衣原体生殖道病理损伤过程的作用。【方法】用1×104IFUs的Mo Pn经生殖道感染野生型(wild type,wt)、LIGHT KO小鼠,每组一半小鼠于感染后49d,再次感染相同剂量的Mo Pn。每隔3-4 d取生殖道分泌物,测定其中衣原体包涵体的数量。初次感染后80d,处死小鼠,眼眶取血,分离血清,用间接免疫荧光法测定其中抗体类型及效价;同时分离生殖道,肉眼观察其输卵管、子宫角水肿程度,然后甲醛固定、切片,H&E染色后,显微镜下观察各组织炎性浸润程度和管腔水肿程度。分离小鼠脾细胞,体外用衣原体EB刺激,测定上清中IL-4、IL-5、IL-17和IFN-γ等细胞因子水平。【结果】LIGHT KO小鼠阴道带菌时间与wt组相当,大部分小鼠均在原发感染后28d左右完全清除感染,且均产生对再次感染的免疫力。LIGHT KO和wt小鼠子宫角和输卵管均出现一定程度的病变,但差异无统计学意义。两组小鼠在原发和继发感染Mo Pn后,均产生高效价的特异性抗Mo Pn Ig G抗体,总抗体及各Ig G抗体亚类效价差异均无统计学意义(P>0.05),且Ig G2a/Ig G1比值均大于1。和wt小鼠一样,LIGHT KO小鼠脾淋巴细胞经衣原体再次刺激后均可产生较高水平的IFN-γ和IL-17,且未能检测到IL-4和IL-5。【结论】小鼠抗Mo Pn生殖道感染及Mo Pn引起的生殖道病理损伤不依赖于LIGHT信号通路。 相似文献
112.
Weiyi Sun Jian Sun Lili Zou Kaini Shen Dingrong Zhong Daobin Zhou Wei Sun Jian Li 《PloS one》2015,10(5)
Laser microdissection followed by mass spectrometry has been successfully used for amyloid typing. However, sample contamination can interfere with proteomic analysis, and overnight digestion limits the analytical throughput. Moreover, current quantitative analysis methods are based on the spectrum count, which ignores differences in protein length and may lead to misdiagnoses. Here, we developed a microwave-assisted filter-aided sample preparation (maFASP) method that can efficiently remove contaminants with a 10-kDa cutoff ultrafiltration unit and can accelerate the digestion process with the assistance of a microwave. Additionally, two parameters (P- and D-scores) based on the exponentially modified protein abundance index were developed to define the existence of amyloid deposits and those causative proteins with the greatest abundance. Using our protocol, twenty cases of systemic amyloidosis that were well-typed according to clinical diagnostic standards (training group) and another twenty-four cases without subtype diagnoses (validation group) were analyzed. Using this approach, sample preparation could be completed within four hours. We successfully subtyped 100% of the cases in the training group, and the diagnostic success rate in the validation group was 91.7%. This maFASP-aided proteomic protocol represents an efficient approach for amyloid diagnosis and subtyping, particularly for serum-contaminated samples. 相似文献
113.
Zewu Li Lutao Du Zhaogang Dong Yongmei Yang Xin Zhang Lili Wang Juan Li Guixi Zheng Ailin Qu Chuanxin Wang 《PloS one》2015,10(1)
Zinc finger protein 217 (ZNF217) is essential for cell proliferation and has been implicated in tumorigenesis. However, its expression and exact roles in colorectal cancer (CRC) remain unclear. In this study, we demonstrated that ZNF217 expression was aberrantly upregulated in CRC tissues and associated with poor overall survival of CRC patients. In addition, we found that ZNF217 was a putative target of microRNA (miR)-203 using bioinformatics analysis and confirmed that using luciferase reporter assay. Moreover, in vitro knockdown of ZNF217 or enforced expression of miR-203 attenuated CRC cell proliferation, invasion and migration. Furthermore, combined treatment of ZNF217 siRNA and miR-203 exhibited synergistic inhibitory effects. Taken together, our results provide new evidences that ZNF217 has an oncogenic role in CRC and is regulated by miR-203, and open up the possibility of ZNF217- and miR-203-targeted therapy for CRC. 相似文献
114.
Yan Li Yunshan Ning Yundan Wang Dandan Peng Yaodong Jiang Lili Zhang Min Long Jun Luo Ming Li 《BMC biotechnology》2010,10(1):84
Background
Urease B is an important virulence factor that is required for Helicobacter pylori to colonise the gastric mucosa. Mouse monoclonal antibodies (mAbs) that inhibit urease B enzymatic activity will be useful as vaccines for the prevention and treatment of H. pylori infection. Here, we produced murine mAbs against urease B that neutralize the enzyme's activity. We mapped their epitopes by phage display libraries and investigated the immunogenicity of the selected mimotopes in vivo. 相似文献115.
Gong G Dai Y Fan B Zhu H Zhu S Wang H Wang L Tang B Li R Wan R Liu Y Huang Y Zhang L Sun X Li N 《Molecular reproduction and development》2004,69(3):278-288
The present study examined effects of genetic manipulation and serum starvation on in vitro developmental potential of bovine somatic cell nuclear transfer (SCNT) embryos and vitrification on in vivo developmental competence of transgenic SCNT blastocysts. Fetal oviduct epithelial cells (FOECs) were isolated from the oviduct of a Day 147 bovine fetus and transfected with a plasmid (pCE-EGFP-IRES-NEO) containing the enhanced green fluorescent protein (EGFP) and neomycin-resistant (Neor) genes. There were no significant differences (P > 0.05) in cleavage rates or development rates to the blastocyst stage for SCNT embryos derived from FOECs (72.5 and 47.8%, respectively) or transfected FOECs (TFOECs, 73.8 and 47.7%, respectively); nor from serum-fed (73.6 and 47.2%, respectively) or serum-starved (72.7 and 48.3%, respectively) cells. Seventeen of Day 7 GFP-embryos (eight fresh blastocysts and nine vitrified/thawed blastocysts ) were transferred to recipients with one embryo per recipient. Two (25%) recipients were confirmed pregnant at Day 60 in fresh blastocysts group, and three recipients (33%) were confirmed pregnant at Day 60 in vitrified/thawed blastocysts group. Two healthy calves (25%) were obtained from fresh blastocysts and one (11%) from vitrified/thawed blastocysts. Microsatellite analysis confirmed that the three clones were genetically identical to the donor cells. Moreover, PCR and Southern blot demonstrated integration of transgene in genomic DNA of all three cloned calves. Expression of GFP in skin biopsies isolated from transgenic cloned calves and fibroblasts derived from the skin biopsies revealed the activity of EGFP gene, and G418 resistance in vitro of these fibroblasts confirmed the activity of Neor gene. Our results show that genetic manipulation and serum starvation of donor cells (FOECs) do not affect in vitro developmental competence of bovine SCNT embryos, and vitrified transgenic SCNT blastocysts can develop to term successfully. 相似文献
116.
117.
Yaoming Li Wangwang Lv Lili Jiang Lirong Zhang Shiping Wang Qi Wang Kai Xue Bowen Li Peipei Liu Huan Hong Wangmu Renzen A Wang Caiyun Luo Zhenhua Zhang Tsechoe Dorji Neslihan Ta Zhezhen Wang Huakun Zhou Yanfen Wang 《Global Change Biology》2019,25(10):3438-3449
Changes in labile carbon (LC) pools and microbial communities are the primary factors controlling soil heterotrophic respiration (Rh) in warming experiments. Warming is expected to initially increase Rh but studies show this increase may not be continuous or sustained. Specifically, LC and soil microbiome have been shown to contribute to the effect of extended warming on Rh. However, their relative contribution is unclear and this gap in knowledge causes considerable uncertainty in the prediction of carbon cycle feedbacks to climate change. In this study, we used a two‐step incubation approach to reveal the relative contribution of LC limitation and soil microbial community responses in attenuating the effect that extended warming has on Rh. Soil samples from three Tibetan ecosystems—an alpine meadow (AM), alpine steppe (AS), and desert steppe (DS)—were exposed to a temperature gradient of 5–25°C. After an initial incubation period, soils were processed in one of two methods: (a) soils were sterilized then inoculated with parent soil microbes to assess the LC limitation effects, while controlling for microbial community responses; or (b) soil microbes from the incubations were used to inoculate sterilized parent soils to assess the microbial community effects, while controlling for LC limitation. We found both LC limitation and microbial community responses led to significant declines in Rh by 37% and 30%, respectively, but their relative contributions were ecosystem specific. LC limitation alone caused a greater Rh decrease for DS soils than AMs or ASs. Our study demonstrates that soil carbon loss due to Rh in Tibetan alpine soils—especially in copiotrophic soils—will be weakened by microbial community responses under short‐term warming. 相似文献
118.
Zeolitic imidazolate framework‐8 (ZIF‐8) loading rhodamine‐B (ZIF‐8@rhodamine‐B) nanocomposites was proposed and used as ratiometric fluorescent sensor to detect copper(II) ion (Cu2+). Scanning electron microscopy, Fourier transform infrared spectroscopy, X‐ray powder diffraction, nitrogen adsorption/desorption isotherms and fluorescence emission spectroscopy were employed to characterize the ZIF‐8@rhodamine‐B nanocomposites. The results showed the rhodamine‐B was successfully assembled on ZIF‐8 based on the π‐π interaction and the hydrogen bond between the nitrogen atom of ZIF‐8 and –COOH of rhodamine‐B. The as‐obtained ZIF‐8@rhodamine‐B nanocomposites were octahedron with size about 150–200 nm, had good water dispersion, and exhibited the characteristic fluorescence emission of ZIF‐8 at 335 nm and rhodamine‐B at 575 nm. The Cu2+ could quench fluorescence of ZIF‐8 rather than rhodamine‐B. The ZIF‐8 not only acted as the template to assemble rhodamine‐B, but also was employed as the signal fluorescence together with the fluorescence of rhodamine‐B as the reference to construct a novel ratiometric fluorescent sensor to detect Cu2+. The resulted ZIF‐8@rhodamine‐B nanocomposite fluorescence probe showed good linear range (68.4 nM to 125 μM) with a low detection limit (22.8 nM) for Cu2+ combined with good sensitivity and selectivity. The work also provides a better way to design ratiometric fluorescent sensors from ZIF‐8 and other fluorescent molecules. 相似文献
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