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41.
AIM: To investigate the effect of paricalcitol (P) on renal tubulointerstitial fibrosis and the underlying mechanisms in diabetic nephropathy (DN).METHODS: DN rat model was induced by a single intraperitoneal injection of streptozotocin after fasting. The animals were randomly divided into 2 groups:the DN rats in paricalcitol-intervened group (group P) were injected intraperitoneally with paricalcitol dissolved in propylene glycol after the day when the model was induced successfully at a dose of 0.4 μg/kg (3 times a week); the DN rats in DN group (group D) were given isopyknic propylene glycol. Normal control group (group C) was also set up. The samples of blood, urine and renal tissue were collected after intervention of paricalcitol for 12 weeks. The biochemical indexes were measured. The renal tissues were used for pathologic observation and determining the expression of transforming growth factor-β1 (TGF-β1), Wnt-4, β-catenin and Klotho by immunohistochemistry and Western blotting. In addition, the correlation among the above indexes was analyzed.RESULTS: (1) Scr, BUN and 24 h urine protein increased significantly in group D compared with group C, while decreased in group P compared with group D (P<0.05). (2) The area of renal tubulointerstitial fibrosis increased in group D compared with group C, while decreased in group P compared with group D (P<0.05). (3) The expression of Klotho decreased, while the expression of TGF-β1, Wnt-4 and β-catenin increased in group D compared with group C (P<0.05). Compared with group D, the expression of Klotho increased, while the expression of TGF-β1, Wnt-4 and β-catenin decreased in group P (P<0.05). (4) The expression of Klotho was negatively correlated with the fibrosis area, TGF-β1, Wnt-4 and β-catenin (P<0.05).CONCLUSION: Paricalcitol inhibits renal tubulointerstitial fibrosis in DN by promoting the expression of renal Klotho, and inhibiting Wnt/β-catenin signaling pathway activation and TGF-β1 synthesis. 相似文献
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43.
Oriental persimmon (Diospyros kaki) originated in Eastern Asia, and many indigenous cultivars have been developed in China, Japan, and Korea. These cultivars are classified into four groups based on their natural astringency loss on the tree and seed formation: pollination-constant non-astringent (PCNA), pollination-variant non-astringent (PVNA), pollination-constant astringent (PCA), and pollination-variant astringent (PVA). PCNA is the most desirable type because the fruit can be eaten without any postharvest treatment; therefore, one of the goals of our persimmon breeding programs is to release superior PCNA cultivars. The PCNA genotype is recessive to the other three non-PCNA genotypes, and PCNA-type F1 offspring are obtained exclusively from crosses among PCNA genotypes. Moreover, the number of superior PCNA cross-parents have been limited. In the late 1980s, inbreeding depression became obvious, especially in terms of fruit size, tree vigor, and productivity. To mitigate the inbreeding, a backcross program using PCNA [(non-PCNA × PCNA) × PCNA] was started in 1990. This process, however, was inefficient because only 15% of the offspring were PCNA, and all offspring had to be grown to the fruiting stage. Therefore, molecular markers linked to the PCNA locus were developed for discriminating PCNA offspring. A molecular marker linked to Chinese PCNA has also been developed. 相似文献
44.
AIM: To observe the therapeutic effect of Jiedu-Qingfei mixture on Mycoplasma pneumoniae (MP)-infected rat lung tissues and to explore its mechanism. METHODS: SD rats (n=40) were randomly divided into 4 groups:blank control group, model group, Jiedu-Qingfei group and positive control group, with 10 rats in each group. The rats in experimental groups were slowly dripped with 1×109 CFU/L MP solution into their nostrils for 4 d. One rat in each group was sacrificed for MP nucleic acid detection at the second day after inoculation, and the other rats were given gavage therapy. The rats in blank control group and model group were intragastrically given the same volume of normal saline, the rats in Jiedu-Qingfei group were given 8 mL/kg Jiedu-Qingfei mixture daily for 4 weeks, and the rats in psoitive control group were given dexmethasone sodium phosphate (0.5 mg·kg-1·d-1). After the experiment, the rats were killed. The serum and bronchoalveolar lavage fluid (BALF) were collected for detecting the levels of interleukin-12 (IL-12), IL-13 and TNF-α by ELISA. The right lung tissues were used for pathological observation and HE staining, while the left lung tissues were used to detect the expression of NF-κB p50, I-κBα and p38 mitogen-activated protein kinase (p38 MAPK) at mRNA and protein levels. RESULTS: The results of MP nucleic acid detection showed that all the rats except blank control group were MP nucleic acid positive, indicating that the rat model of MP infection was successfully established. On the 1st day of the treatment, the pathological scores of the lung tissues in model group and Jiedu-Qingfei group were significantly higher than those in blank control group (P<0.05). After treatment, the pathological scores of the lung tissues in mo-del group were significantly higher than those in blank control group and Jiedu-Qingfei group. The levels of IL-12 in the serum and BALF in model group were significantly lower than those in blank control group after MP infection (P<0.05), while those after treatment with Jiedu-Qingfei mixture were significantly higher than those in model group (P<0.05). The levels of IL-13 and TNF-α in the serum and BALF of MP-infected rats were increased significantly, while those after treatment with Jiedu-Qingfei mixture were significantly lower than those in model group (P<0.05). The mRNA expression levels of NF-κB p50 and p38 MAPK in model group were increased significantly (P<0.01). After treatment, the mRNA expression levels of NF-κB p50 and p38 MAPK were decreased significantly compared with model group (P<0.01). The mRNA expression level of I-κBα in model group was significantly lower than that in control group. After treatment, the mRNA expression of I-κBα in Jiedu-Qingfei group was significantly higher than that in model group (P<0.05). The protein levels of NF-κB p50 and p38 MAPK in the lung tissues of model group were significantly higher than those of blank control group. After treatment, the protein expression of NF-κB p50 and p38 MAPK was decreased significantly. The protein level of I-κBα in model group was significantly lower than that in blank control group, and after treatment with Jiedu-Qingfei mixture, the protein expression level of I-κBα was increased significantly (P<0.05). CONCLUSION: Jiedu-Qingfei mixture may attenuate lung tissue inflammation caused by MP through NF-κB and p38 MAPK pathways. 相似文献
45.
Diabetes is characterized by an absolute or relative deficiency in β-cell mass, which cannot be reversed with existing therapeutic strategies. The restoration of the endogenous islet β-cells can stabilize the level of blood glucose. The islet β-cells can be obtained from the directional differentiation of stem cells, but the process is complex and has the risk of teratomas generation. Cell direct reprogramming, one terminal differentiated cell can transdifferentiate into another kind of terminal differentiated cell, which is other than directional differentiation from stem cells. Direct reprogramming gives rise to the generation of islet β-cells from one terminal differentiated cell, may be preferable for diabetes therapy because of its unique advantage. 相似文献
46.
47.
湘紫薯174 是以浙紫薯1 号为母本、浙紫薯3 号为父本杂交选育而成的食用型紫心甘薯新品种,薯块纺锤形,薯皮
紫红色,薯肉紫色,结薯较集中整齐,单株结薯4~5 个,大中薯率82.7% 以上,熟食味好,抗黑斑病,中抗根腐病、茎线
虫病和薯瘟病;每667 m2 鲜薯产量1 913~2 359 kg,薯干产量549~736 kg;花青素含量为714.5 mg · kg-1(FW)。适宜在湖
南、湖北、江西、江苏、浙江等地春夏薯区种植。 相似文献
48.
Eleven grape cultivars were analysed to explore the variety differences of fresh grape phenolic profiles. The results showed that free phenolics were predominant in grape skins and pulps, and showed the higher antioxidant activities than bound. In 11 cultivars, Muscat Kyoho extracts had the highest total phenolic content in skins(10.525 mg GAE g~(–1) FW) and pulps(1.134 mg GAE g~(–1) FW), and exhibited the highest DPPH radical scavening capacity(EC_(50)=11.7 μg mL~(–1)) and oxygen radical absorbance capacity(ORAC) value(190.57 μmol TE g~(–1) FW) of free phenolic in skin. In addition, the most abundant phenolics in grape skins were found to be flavonoids such as kaempferol in Kyoho skin(541.2 μg g~(–1) FW), rutin, catechin and epicatechin in Muscat Kyoho skin(262.3, 86.3 and 70.0 μg g~(–1) FW, respectively). Furthermore, the principal component analysis showed a strong difference of phenolic profiles with the cultivars, existing forms and distributions. Pearson correlation coefficient analysis showed a significant linear correlation between total phenolic content and antioxidant activity(P0.05). Therefore, both skins and pulps were rich sources of bioactive phenolic compounds, and Muscat Kyoho was the ideal source among all samples. 相似文献
49.
AIM: To observe the treatment effect and its immune regulation of human amnion epithelial cells (hAECs) on Alzheimer's disease (AD)-like pathology rat model. METHODS: The hAECs were isolated from amnion with trypsin digestion, and the phenotype of hAECs was analyzed by flow cytometry. SD rats (n=48) were randomly divided into sham control group, model group, medium group and hAECs group. AD-like pathology rat model was induced by bilateral intraventricular injection of lipopolysaccharide (LPS). hAECs (5×105) were injected into the hippocampus of the AD-like pathology rats. At 2 weeks after transplantation, the animals were tested by Morris water maze to observe the function of learning and memory. The pathological change of the brain was observed by HE staining. The expression of amyloid β-protein 42(Aβ42) and Tau protein and the level of acetylcholine (ACh) in the injury brain were determined by immunohistochemistry. The survival and differentiation of hAECs in the hippocampus were measured by immunofluorescent technique. The percentages of lymphocyte subsets in the peripheral blood mononuclear cells were analyzed by flow cytometry. The contents of serum cytokines were detected by cytometric bead array. RESULTS: Compared with model group and medium group, hAECs group showed shortened escape latency (P<0.01), increased frequency of going through the platform (P<0.05), reduced loss of hippocampal neurons, decreased expression of Tau protein and Aβ42 in the hippocampus (P<0.05), increased ACh level in the hippocampus (P<0.05), decreased percentages of Th1 and Th17 subsets, increased percentages of Th2 and Treg cells (P<0.05), decreased concentrations of IFN-γ and IL-2 in the serum, and increased concentration of IL-4(P<0.05). CONCLUSION: hAECs improve the cognitive learning and memory function and alleviate pathologic damage of hippocampus through immune regulation in AD-like pathology rats. 相似文献
50.
WU Xue-lei CAI Yao-wu ZHUANG Zhi-zhong CHEN Yuan-jing GUO Ren-jie ZHENG Mao-song 《园艺学报》2015,31(12):2169-2175
AIM: To explore the mechanism by which over-expression of enhancer of zeste homolog 2 (EZH2) in a panel of gastric cancer cell lines is involved in tumorigenesis of gastric cancer. METHODS: Real-time PCR and Western blot were employed to examine the mRNA and protein levels of EZH2, respectively. MTS assay, cell migration and soft agar assay were performed to investigate the role of EZH2 in the regulation of stomach cancer behaviors. The effect of EZH2 on NF-κB target gene expression was determined by Luciferase reporter and real-time PCR. Co-immunoprecipitation was used to analyze the interaction of EZH2 and p65 in HEK293T cells. RESULTS: The expression levels of EZH2 were significantly increased in the gastric cancer cells compared with normal gastric epithelial cells. Pharmacological inhibition by DZNep or knockdown of EZH2 significantly compromised AGS and SNU-16 cell activity, cell migration and anchorage-independent cell growth. Moreover, siRNA knockdown of EZH2 impaired NF-κB downstream targets, such as IL-8, CXCL5 and CCL20. In addition, the interaction of EZH2 and p65 was detected. CONCLUSION: EZH2 mediates the growth of gastric cancer cells through the regulation of NF-κB downstream gene expression. 相似文献