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181.
AIM: To explore the relationship between FRAS1 protein and brain metastases of non-small cell lung cancer (NSCLC).METHODS: The mRNA expression of FRAS1 in the brain metastatic tumor tissues and primary tumor tissues of NSCLC was detected by qPCR. The protein expression of FRAS1 in the tumor tissues and normal tissues adjacent to tumor tissues of NSCLC was measured by SP method of immunohistochemistry. The protein expression of FRAS1 in NSCLC primary tumor tissues with or without brain metastases was also determined.RESULTS: The mRNA expression of FRAS1 in the brain metastatic zone was nearly 10 times higher than that in the primary tumor tissues, and there was significant difference between the 2 groups (P<0.05). FRAS1 protein was expressed in the NSCLC primary tumor tissues, but was not found in the normal tissues adjacent to primary tumor tissues. The protein expression of FRAS1 in the NSCLC with brain metastases was significantly higher than that without brain metastases (P<0.01).CONCLUSION: FRAS1 protein may be associated with the occurrence of NSCLC. The over-expression of FRAS1 protein may be related to brain metastases with NSCLC.  相似文献   
182.

Background

The carrier status of lavender foal syndrome (LFS), cerebellar abiotrophy (CA), severe combined immunodeficiency (SCID), and occipitoatlantoaxial malformation (OAAM1) in foals with juvenile idiopathic epilepsy (JIE) is unknown.

Hypothesis/Objectives

To determine the carrier status of LFS, CA, SCID, and OAAM1 in foals with JIE.

Animals

Ten foals with JIE.

Materials and Methods

Archived DNA samples were tested for known genetic mutations causing LFS, CA, SCID, and OAAM1. The inclusion criteria consisted of having been diagnosed with JIE by ruling out other causes of seizures in foals and supported by electroencephalographic examination.

Results

Ten Egyptian Arabian horses (5 females and 5 males) were phenotyped as foals with JIE by electroencephalography (EEG). All foals were negative for the genetic mutations that cause LFS, CA, SCID, and OAAM1 except for 1 foal that was a carrier of CA.

Conclusions and Clinical Importance

Juvenile idiopathic epilepsy of Egyptian Arabian foals and LFS appear to be phenotypically and genetically distinct disorders. There was no apparent association between JIE and LFS, CA, SCID, and OAAM1.  相似文献   
183.
Production of knockout mice using targeted embryonic stem cells (ESCs) is a powerful approach for investigating the function of specific genes in vivo. Although the protocol for gene targeting via homologous recombination (HR) in ESCs is already well established, the targeting efficiency varies at different target loci and is sometimes too low. It is known that knockdown of the Bloom syndrome gene, BLM, enhances HR-mediated gene targeting efficiencies in various cell lines. However, it has not yet been investigated whether this approach in ESCs is applicable for successful knockout mouse production. Therefore, we attempted to answer this question. Consistent with previous reports, Blm knockdown enhanced gene targeting efficiencies for three gene loci that we examined by 2.3–4.1-fold. Furthermore, the targeted ESC clones generated good chimeras and were successful in germline transmission. These data suggest that Blm knockdown provides a general benefit for efficient ESC-based and HR-mediated knockout mouse production.  相似文献   
184.
MicroRNA(miRNA)是一类内源性的非编码RNA,参与调节病毒复制、细胞增殖或凋亡以及肿瘤发生等生物反应。本研究探讨了miR-130c-5p在乌鳢水泡病毒(snakehead vesiculovirus, SHVV)感染中潜在靶基因g的靶向关系以及对病毒复制的影响。本研究以斑点叉尾鮰卵巢(Channel catfish ovary, CCO)为实验材料,通过qRT-PCR和Western blot测定SHVV不同感染时间和感染剂量条件下,病毒基因水平和蛋白水平以及miR-130c-5p变化情况。此外,将SHVV的g基因上miR-130c-5p对应的靶序列克隆到质粒pmirGLO,构建质粒pmirGLO-G用于双荧光素酶报告实验进行靶基因验证。结果显示,随着SHVV感染时间及剂量的不断增加,miR-130c-5p和g基因的表达水平都显著上调。进一步实验证明,miR-130c-5p类似物和pmirGLO-G质粒共转染可显著抑制荧光素酶活性强度,而转染miR-130c-5p抑制剂则明显上调了pmirGLO-G报告载体的荧光信号。此外,miR-130c-5p的过表达显著降低了病毒G基因的mRNA及蛋白表达,而抑制miR-130c-5p的表达则上调了g基因的mRNA及蛋白的表达水平。研究结果表明,miR-130c-5p通过靶向SHVV的g基因,引起G蛋白的降解,从而抑制SHVV的增殖。本研究结果为理解microRNA调控SHVV的致病机制提供了重要基础,为抗SHVV疫苗等药物的研发提供了理论支持。  相似文献   
185.
Turbot larvae were fed live-prey enriched with different levels of arachidonic (ARA) and eicosapentaenoic (EPA) acids to study the effects of these fatty acids on body composition and pigmentation success. Significantly reduced pigmentation was obtained in those fish fed medium and high ARA diets for 43 days. Growth and survival were the same for all groups. The incorporation of ARA and EPA in fish eyes, brains, livers and carcasses reflected the percentage of these fatty acids in the diets. ARA accumulation was similar in all tissues, but brain accumulated EPA was less efficient than the other tissues examined. A highly significant, negative correlation was found between the %ARA in turbot juvenile brain total lipids and pigmentation success. A weaker, positive correlation was found between brain EPA and pigmentation. Increasing dietary ARA affected the fatty acid composition of turbot brain phosphoglycerides more than increasing dietary EPA, especially in phosphatidylinositol (PI) and phosphatidylethanolamine (PE). A negative relationship was found between percentage normal pigmentation and ARA levels in brain phosphatidylcholine (PC), PE and phosphatidylserine (PS). Elevated levels of ARA in PI also resulted in malpigmented juveniles, but EPA:ARA ratios ≥1 in PI were associated with normal pigmentation. We conclude that, given a sufficiency of dietary docosahexaenoic acid (DHA), the optimum dietary level of EPA is not a function of DHA, but of dietary ARA.  相似文献   
186.
琼脂糖凝胶电泳在水稻EcoTILLING技术中的应用   总被引:4,自引:0,他引:4  
为构建低成本的基于琼脂糖凝胶电泳的EcoTILLING技术体系,用于水稻及其他生物自然群体变异的检测,对基于琼脂糖凝胶的EcoTILLING技术进行了优化。结果表明,从芹菜中提取的CEL Ⅰ核酸酶粗提物结合琼脂糖凝胶电泳检测技术,可以成功地检测到目的基因位点的突变。利用该技术,在云南地方水稻品种大吊糯中检测到2 个SNPs。  相似文献   
187.
tRNase Z是金属-β-内酰胺酶(MBL)超家族中的一员,它与pre-tRNA 3'末端的成熟加工相关。人们普遍对微生物和动物的tRNase Z研究较多,但对植物的tRNase Z认识很少。为了更好地了解植物tRNase Z,我们对10种已测序植物进行tRNase Z同源检索并分析。研究表明植物中存在3种tRNase Z,细菌型tRNase ZS只存在于低等的陆生植物和绿藻类植物中,真核型tRNase ZL和海栖热袍菌型tRNase ZS广泛存在于各类植物中。海栖热袍菌tRNase ZS具有独特的保守模体:KL模体、EgxSxxG模体、xHxT模体和HxH模体。对开花植物的tRNase ZS定位预测显示,海栖热袍菌型tRNase ZS定位于植物细胞的叶绿体中。进一步分析发现,低等植物中存在一些没有tRNase Z活性的tRNase Z-like蛋白。试验结果显示植物的tRNase Z比真菌和动物的更加丰富。海栖热袍菌型tRNase ZS和tRNase Z-like蛋白的发现,丰富了tRNase Z家族,加深了人们对tRNase Z的认识。  相似文献   
188.
BACKGROUND: Hypertrophic cardiomyopathy (HCM) is the most common heart disease of cats, resulting in left ventricular (LV) hypertrophy, myocardial fibrosis, and diastolic dysfunction. HYPOTHESIS: Ramipril will reduce LV mass, improve diastolic function, and reduce myocardial fibrosis in cats with HCM without congestive heart failure (CHF). ANIMALS: This prospective, blinded, placebo-controlled study included 26 Maine Coon and Maine Coon cross-bred cats with familial HCM but without CHF. METHODS: Cats were matched for LV mass index (LVMI) and were randomized to receive ramipril (0.5 mg/kg) or placebo q24h for 1 year, with investigators blinded. Plasma brain natriuretic peptide (BNP) concentration, plasma aldosterone concentration, Doppler tissue imaging (DTI), and systolic blood pressure were measured at baseline and every 3 months for 1 year. Cardiac magnetic resonance imaging (cMRI) was performed to quantify LV mass and myocardial fibrosis by delayed enhancement (DE) cMRI at baseline and 6 and 12 months. Plasma angiotensin-converting enzyme (ACE) activity was measured on 16 cats 1 hour after PO administration. RESULTS: Plasma ACE activity was adequately suppressed (97%) in cats treated with ramipril. LV mass, LVMI, DTI, DE, blood pressure, plasma BNP, and plasma aldosterone were not different in cats treated with ramipril compared with placebo (P = .85, P = .94, P = .91, P = .89, P = .28, P = .18, and P = .25, respectively). CONCLUSION: Treatment of Maine Coon cats with HCM without CHF with ramipril did not change LV mass, improve diastolic function, alter DE, or alter plasma BNP or aldosterone concentrations in a relevant manner.  相似文献   
189.
Although recognized as a possible complication to sepsis, there are few published reports on brain abscesses in foals. This case report describes a 4-month-old Icelandic filly that, as a neonate, had a history of pyrexia and lameness, which resolved with antibiotic treatment. Approximately 3 months later, the foal developed neurological signs which were initially attributed to trauma; she was referred for further investigation. The clinical signs were consistent with a lesion of the right forebrain. Computed tomography examination revealed a mass, approximately 6 cm in diameter, located in the right cerebral hemisphere craniolateral to the right lateral ventricle. Because of the poor prognosis, the foal was killed, and a postmortem was performed. The findings confirmed the presence of an abscess of the right cerebral hemisphere, leading to severe atrophy of the cortex and dilation of both lateral ventricles. The left hemisphere was moderate-to-severe atrophic and had displaced to the left. Streptococcus equi subspecies zooepidemicus was isolated in pure culture from the abscess. The clinical features of the foal were compared with the pathological findings.  相似文献   
190.
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