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11.
经生物学软件DNAStar分析,以牛传染性鼻气管炎病毒(Banha Nu/67)基因组DNA为模板,PCR扩增gD基因943bp的片段,将目的片段定向克隆到pET30a表达载体中,酶切及测序鉴定均正确后,转化BL21表达菌,经IPTG诱导得到部分可溶表达的重组蛋白。用Ni柱亲和层析法在非变性的条件下纯化重组蛋白,纯化的重组蛋白浓度为0.852mg/mL,纯度为85.2%。Westem blot、间接ELISA检测证明纯化的重组蛋白具有良好的抗原性和特异性。  相似文献   
12.
白菜S位点糖蛋白基因的克隆与表达分析   总被引:1,自引:0,他引:1  
 以白菜自交不亲和系为材料,采用RT-PCR技术,用特异引物对SLG基因进行克隆,获得SLG基因cDNA序列长度为1 324 bp,命名为BcSLG。序列分析表明:所获得的白菜BcSLG基因cDNA序列包含一完整的编码框,编码432个氨基酸,含有12个保守的半胱氨酸残基和7个N-糖基化位点。序列比对和系统进化分析表明:BcSLG与其它植物的SLG基因氨基酸序列具有较高的同源性,与大白菜和甘蓝亲缘关系最近。荧光定量PCR分析表明:BcSLG基因在自交不亲和系的柱头中表达量最高,其次是花蕾,叶片中表达最低, 在自交亲和系的柱头、花蕾和叶片中相对表达较低。  相似文献   
13.
研究以鸡传染性喉气管炎病毒(ILTV)烟台株为模板,PCIK扩增出1条约2.7的gB基因片段,并将其克隆到pMD18-T载体中。序列测定显示,gB基因长2622bp,包含完的阅读框架。序列比较分析发现,烟台株和王岗株、河北株的班基因核苷酸序列与SA2株的比均在第89位上缺失1个碱基G,而在第102位核苷酸处插入1个碱基A,从而引起氨基酸序中第29-32位5个氨基酸的移码突变。烟台株还有另外7个碱基发生突变,使得其班基因与北株、王岗株、SA2疫苗株的gB基因核苷酸同源性分别为99.8%、99.7%和99.6%,氨基酸的同性分别为99.4%、99.4%、98.9%,表明不同ILTV毒株之间gB基因是非常保守的。划型相列河源  相似文献   
14.
A cDNA encoding the subunit of thyrotropin (TSH) was isolated from a goldfish (Carassius auratus) pituitary gland cDNA library. By comparing the sequence with other teleost TSHs, a signal peptide of 19 amino acids and a mature hormone of 131 amino acids were predicted for goldfish TSH subunits. The resulting putative mature hormone of 131 amino acids had well-conserved cysteine positions and a putative N-linked glycosylation site; homology was 51–67% with TSHs from other teleosts, 38–43% with tetrapod TSHs, but only 27 and 29% with goldfish GTH-I and -II, respectively. We also examined the effects of thyroid hormones (TH) and thiourea (TU, an inhibitor of TH production) treatments on TSH and GTH subunit gene expressions in the goldfish pituitary gland. After thyroxine (T4) treatment, circulating T4 concentration increased and TSH mRNA level decreased. Supressing the amount of circulating T4 and triiodothyronine (T3) by TU treatment increased the TSH mRNA level. Moreover, T4 replacement therapy (simultaneous treatment of both TU and T4) caused a high level of circulating T4 and a low level of circulating T3, and a decrease in the TSH mRNA level. Thus, changing levels of circulating TH exert a negative feedback on the level of TSH subunit mRNA in goldfish in vivo. On the other hand, GTH subunit mRNA levels were not affected by changes in the levels of circulating TH.  相似文献   
15.
The aim of this study was to assess whether Holy Birman cats (HB) have a peculiar immune profile and a higher rate of infection by feline coronaviruses (FCoV). Leucocyte and lymphocyte subsets, antibody titers, α1-acid glycoprotein (AGP), globulin fractions, IL-4, IL-12 and IFN-γ in blood and fecal FCoV excretion were determined in HB (n = 75) and in cats from other breeds (n = 94). Significantly higher CD4/CD8 ratio, IFN-γ concentration and IL12/IL4 ratio and significantly lower IL-4 concentration and proportion of shedders were found in HB than in other breeds. No other differences were found. In conclusion, this study did not provide evidence of peculiar immune profiles in HB, except for a prevalent Th1 profile, that may explain why in our caseload the rate of shedders was lower in HB than in other breeds.  相似文献   
16.

Background

Thyroid carcinoma is a common endocrine tumor in the dog. Local invasive growth frequently precludes surgical excision and, in up to 38% of dogs, the tumor has already metastasized by the time of diagnosis. Therefore, it is important to investigate new treatment modalities that may be useful for the large number of dogs with inoperable tumors or metastatic disease.

Hypothesis/Objectives

To investigate the immunohistochemical expression of potential therapeutic targets in canine thyroid tumors.

Animals

74 dogs with thyroid neoplasia.

Methods

Immunohistochemistry was performed for thyroglobulin, calcitonin, vascular endothelial growth factor (VEGF), p53, cycloxygenase‐2 (cox‐2), and P‐glycoprotein (P‐gp).

Results

Fifty‐four (73%) tumors were classified as follicular cell thyroid carcinomas (FTCs) and 20 (27%) as medullary thyroid carcinomas (MTCs). Eighty percent of FTCs and all MTCs had a high percentage (76–100%) of neoplastic cells immunopositive for VEGF. Thirteen percent of FTCs and 50% of MTCs expressed cox‐2. Seven percent of FTCs and 70% of MTCs expressed P‐gp. No tumor was immunopositive for p53 expression. Expression of VEGF (P = .034), cox‐2 (P = .013), and P‐gp (P < .001) was significantly higher in MTCs compared to FTCs.

Conclusions and Clinical Importance

VEGF is a potential therapeutic target in both FTC and MTC in dogs. Cox‐2 and P‐gp may be useful molecular targets in canine MTC.  相似文献   
17.
We determined full-length cDNA of carp warm-temperature-acclimation-associated 65-kDa protein (Wap65). It encoded 439 amino acid residues with a signal peptide of 22 residues and showed an amino acid sequence identity of 88% to that of goldfish reported before (J. Biol. Chem. 1995. 270: 17087–17092). The number of potential N-linked glycosylation sites of carp Wap65 was two in contrast to three for goldfish. In addition, molecular mass determined by SDS-PAGE was apparently different from that of goldfish. These results suggest that the amount of oligosaccharide is different between the carp and goldfish protein. As in goldfish, carp Wap65 mRNA showed marked accumulation in hepatopancreas of the 30 °C- acclimated fish, which was 8-fold higher than that of the 10 °C-acclimated fish. Carp Wap65 showed 30% amino acid identity to mammalian hemopexins, which appeared to be considerably low in comparison with those among mammalian hemopexins (72 to 80%), or among carp Wap65 and rainbow trout hemopexin-like protein (70%). However, although mammalian hemopexins contain residues comprising the heme binding pocket, carp Wap65 lacked one of the two histidine residues to serve as heme axial ligands in hemopexins. Our data on carp protein substantiates the previous observation for goldfish and indicates that Wap65 might have some important functions in warm-temperature-acclimation of fish.  相似文献   
18.
In order to gain nucleocapsid protein (N) and glycoprotein (E) of porcine reproductive and respiratory syndrome virus (PRRSV), the total RNA was extracted,ORF7 and ORF5 genes were obtained by RT-PCR, inserted into pET-28a(+) vector, and then transformed into Escherichia coli BL21(DE3),respectively. The expressed products were identified by SDS-PAGE and Western blotting, and purified by affinity chromatography. The results showed that N and E fusion protein were successfully expressed and the proteins had good reactionogenicities by Western blotting analysis. The purities of the purified proteins were 89% and 90%, respectively. This study could lay foundations for molecular biological function research and establishment of test methods for detection antibodies of PRRSV.  相似文献   
19.
通过双酶切将伪狂犬病毒(Pseudorabies virus,PRV)Fa株gC囊膜糖蛋白基因片段亚克隆到5型腺病毒AdMax系统穿梭质粒pDC316中,得到pDC316-gC。用此质粒与腺病毒DNA辅助质粒pBHGloxΔ E1,3Cre共转染293细胞,包装出重组腺病毒Adv-gC。通过PCR鉴定和病毒空斑纯化,得到纯的高效价Adv-gC病毒液。间接免疫荧光实验证明此重组病毒能表达PRV gC蛋白。该病毒经肌注免疫Balb/c小鼠,能诱导小鼠产生特异的体液和细胞免疫反应。攻毒试验表明,此重组病毒能提供100%的免疫保护。  相似文献   
20.
SARS冠状病毒刺突蛋白S144-643的表达及免疫原性分析   总被引:2,自引:1,他引:2  
将SARS冠状病毒(SARS-CoV)表面的主要结构蛋白刺突蛋白S144-643的基因片段(nt430-nt1929)克隆入表达质粒pET-28b中,并在大肠杆菌中表达。S144-643蛋白分子质量为55 ku左右,以包涵体形式存在于细菌中。ELISA及Western blot证明,S144-643可以与SARS康复病人的阳性血清发生特异性反应,免疫新西兰大白兔可以诱发产生较高水平的特异性抗体,因而证明原核表达的S144-643具有良好的免疫原性。  相似文献   
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