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151.
为了阐明树鼩精子中是否存在丝氨酸/苏氨酸蛋白磷酸酶1γ2(PP1γ2)及其在附睾精子中的存在形式,进而探究PP1γ2对精子成熟和运动性的调控作用,本试验以树鼩为研究对象,采用Western blotting分析了不同条件下树鼩附睾头和附睾尾精子中PP1γ2的存在形式和磷酸化程度,探讨了双丁酰环腺苷酸(db-cAMP)、3-异丁基-1-甲基黄嘌呤(IBMX)或Ca2+对树鼩精子中PP1γ2磷酸化表达水平的影响,并进一步研究了磷酸酶抑制剂冈田酸(okadaic acid,OA)和花萼海绵诱癌素A(calyculin A,CA)对树鼩精子中PP1γ2磷酸化程度的影响及其对树鼩附睾头和附睾尾精子运动度的影响。结果显示,在树鼩附睾头和附睾尾精子中均存在PP1γ2,且在等量的附睾头和附睾尾精子蛋白中,PP1γ2在附睾尾精子的磷酸化程度远高于附睾头精子;db-cAMP、IBMX或Ca2+不改变PP1γ2的磷酸化水平;磷酸酶抑制剂OA和CA能明显提高附睾头和附睾尾中PP1γ2磷酸化的程度,且能显著提高精子(尤其是附睾头精子)的运动度(P<0.05),OA和CA的最佳作用浓度分别为1μmol/L和10 nmol/L,最佳作用时间分别为15、20 min。本研究结果表明,蛋白磷酸酶PP1γ2对树鼩精子成熟及运动性具有重要的调控作用,其主要通过磷酸化和去磷酸化的变化发挥作用。 相似文献
152.
Jiro Sonoda Yuki Seki Atsushi Hakura Satoru Hosokawa 《Journal of toxicologic pathology》2015,28(2):109-120
Benzo[a]pyrene (BP) is mutagenic but noncarcinogenic in the murine colon. Recently, we reported rapid induction of colonic tumors by treatment of CD2F1 mice with BP (125 mg/kg for 5 days) followed by a colitis inducer, dextran sulfate sodium (DSS) (4% in drinking water for 1 or 2 weeks). However, there are no reports on detailed time course and histopathological features of colonic proliferative lesions in this model. Here, we show the detailed time course of colonic dysplasia, adenoma and adenocarcinoma induced by treatment with BP, DSS, and a combination of the two (BP/DSS). In the colon of mice exposed to BP/DSS, 14.6 dysplastic foci per mouse were present one week after DSS treatment (week 4). The number of dysplastic foci decreased with time to 3.1 at week 9 and thereafter remained almost constant. At week 4, 1.5 adenocarcinomas were also observed, with a marked increase in numbers with time, reaching 29.3 at week 14. In contrast, the number of dysplastic foci induced by DSS alone showed a time course similar to that following BP/DSS treatment; however, only a few tumors appeared. Neither dysplastic foci nor neoplastic lesions were induced by BP only. In mice exposed to BP/DSS, ;2;-catenin was demonstrated immunohistochemically in the nucleus and/or cytoplasm of the tumor cells, and this translocation from the cell membrane was evident in subsets of dysplastic foci. In dysplastic foci induced by DSS alone, ;2;-catenin was absent in the nucleus/cytoplasm. These finding suggest that aberrant ;2;-catenin accumulation in dysplastic foci is associated with tumor progression in this BP/DSS model. 相似文献
153.
陈学文 《青海畜牧兽医杂志》1998,28(5):7-9
1994~1996年在海南州赛什塘牧场对1/2和1/4野血牦犊牛的生长发育进行了观测。结果:1/2和1/4野血牦犊牛的初生重分别比家牦犊牛提高7.65%和8.86%(P<0.01),1/2野血牦犊牛在初生时的体高、体长和胸围比家牦犊牛分别提高3.21%,5.57%,5.51%;6月龄时分别提高9.56%,11.46%,3.59%;18月龄时分别提高9.18%,17.55%,7.64%(P<0.01)。 相似文献
154.
为调查规模化猪场不同年龄猪群中2型猪链球菌(S.suis 2)抗体水平,本研究采用以荚膜多糖为抗原的间接ELISA对来自广西地区母猪群、肥猪群、生长猪群共1 908份血清样品进行了S.suis 2抗体检测和分析。结果显示:成年猪群中抗S.suis 2的抗体水平普遍较高,种猪场母猪血清抗体阳性率可高达95%以上,不同地区屠宰场的育肥猪血清抗体阳性率在39.2%~97.5%。对不同日龄仔猪群抗体水平检测分析显示:14日龄~42日龄期间,抗体水平随仔猪日龄的增长而呈逐渐下降的趋势;而42日龄~130日龄期间,抗体水平随日龄的增长而呈逐渐上升的趋势。此外,经产母猪群抗体水平略高于后备母猪群,并且随胎次的增加,抗体的离散度缩小。以上结果表明S.suis 2抗体在仔猪生长阶段的空白期即42日龄时,仔猪群抗体水平最低。因此,在这个阶段和之前做好S.suis的预防和免疫工作对猪群链球菌病的防控至关重要。 相似文献
155.
探究茉莉酸甲酯(Methyl Jasmonate,MeJA)和磷酸氢二钾(K2HPO4)诱导柱花草对炭疽病的抵抗作用。结果表明,二者浓度分别为0.001~0.1 mgmL-1和10~50 mmolL-1时,病情指数均显著降低(P0.05),最佳诱导浓度分别是0.001 mgmL-1和30 mmolL-1,诱导效果分别是64.84 %和54.40 %。0.001 mgmL-1 MeJA处理组的过氧化物酶(POD)及多酚氧化酶(PPO)活性在48 h达到最大值,显著高于对照组。30 mmolL-1 K2HPO4处理组的POD与PPO活性分别在48和24 h达到最大值,显著高于对照组。两种诱抗剂处理的POD和PPO活性在接种早期增加了柱花草对炭疽菌的侵染的抵御能力,进而提高植株的抗病性。30 mmolL-1 K2HPO4处理组的过氧化氢酶(CAT)活性在48~72 h内上升,显著高于对照组,而0.001 mgmL-1 MeJA处理组的CAT活性除72 h显著低于对照组,其他时间点与对照组相差不大。说明在诱导柱花草抗病性方面,两种诱导抗性剂处理的诱抗效果与POD、PPO和CAT的酶活性的诱导的时间及程度有关。 相似文献
156.
Mammary tumours are the most common neoplasms in humans and canines. Human and canine mammary tumours share several important epidemiological, clinicopathological and biochemical features. Development of mammary tumours involves accumulation of mutant cells caused by excessive proliferation and insufficient apoptosis or dysregulation of cellular differentiation. The present study was therefore designed to investigate the expression of proliferation, differentiation, and apoptosis associated proteins together with expression of estrogen receptors (ER) in both human and canine mammary tumours. Thirty breast cancer patients categorized as pre- and postmenopausal, and 30 mammary gland tumours obtained from bitches were included in this study. The expression of proliferating cell nuclear antigen (PCNA), Bcl-2, p53, cytokeratin and ER in tumour tissues and adjacent tissues were investigated using immunohistochemical staining. While the expression of PCNA, Bcl-2, p53 and ER was significantly increased, expression of cytokeratin was significantly lower in both human as well as canine mammary tumours compared to corresponding adjacent tissues. The magnitude of the changes was however more pronounced in premenopausal patients compared to postmenopausal patients. The changes in proliferation, apoptosis and differentiation associated proteins in human and canine mammary tumours validate use of the canine model to understand the molecular mechanisms of mammary carcinogenesis. 相似文献
157.
通过对高原植物香芸火绒草超临界CO2萃取的研究,获得了温度45℃、压力18MPa为其相对较佳提取条件,提取产物为黄绿色浸膏,得率为0.87%。将该浸膏精制成净油,其得率为60.2%。进一步通过气相色谱-质谱联用技术(GC—MS)对净油分析,鉴定出其中的15种化学成分,并通过峰面积归一法确定了它们的相对含量。挥发油成分主要为:邻苯二甲酸异辛酯、高良姜素黄烷酮、α-甜没药萜醇、橙花叔醇、胡萝卜醇、棕榈酸等。通过对香芸火绒草挥发油成分的研究,为高原特有植物资源的进一步开发利用提供了试验依据。 相似文献
158.
Alexander Valverde DVM DVSc DACVA Cornelia I. Gunkel Dr. med. vet. MRCVS 《Journal of Veterinary Emergency and Critical Care》2005,15(4):295-307
Objective: This review discusses the different analgesic drugs and routes of administration used in large animals for acute pain management. General guidelines and doses are given to assist in choosing techniques that provide effective analgesia. Etiology: Noxious stimuli are perceived, recognized, and localized by specialized sensory systems located at spinal and supraspinal levels. Diagnosis: Localizing the source of the noxious stimulus as well as understanding the behavioral aspects and physiological changes that result from such insult is important to adequately diagnose and treat pain. Pain assessment is far from being definite and objective; not only are there species differences, but also individual variation. In addition, the behavioral and physiological manifestations vary with the acute or chronic nature of pain. Therapy: Pain management should include (1) selecting drugs that better control the type of pain elicited by the insult; (2) selecting techniques of analgesic drug administration that act on pathways or anatomical locations where the nociceptive information is being processed or originating from; (3) combining analgesic drugs that act on different pain pathways; and (4) provide the best possible comfort for the animal. Prognosis: Providing pain relief improves the animal's well being and outcome; however, interpreting and diagnosing pain remains difficult. Continuing research in pain management will contribute to the evaluation of the pathophysiology of pain, pain assessment, and newer analgesic drugs and techniques. 相似文献
159.
采用RT-PCR方法从鸭源呼肠孤病毒DRV—GZ株中扩增出了S2基因片段,将其克隆到表达载体pET-28a(+)中,测序验证后转化入表达宿主菌Rosetta^TM2(DE3)plysS,进行IPTG诱导表达。结果表明,重组菌可表达出相对分子质量约为50000的重组融合蛋白,在浓度为0.6mmol/L的IPTG诱导4h的情况下表达效果最好。表达的蛋白以包涵体的形式存在于菌体中。表达产物经Ni柱纯化后可得到纯度较高的目的蛋白。经Western-blot分析,所纯化的蛋白能与抗呼肠孤病毒DRV—GZ株阳性血清进行特异性的免疫印迹反应,证实表达的蛋白具有较好的反应原性。 相似文献
160.
以野生斑马鱼为模式动物,对6株mrp+epf+sly+猪链球菌2型(SS2)分离株进行致病性比较。斑马鱼经腹腔接种不同稀释度的SS2分离株,连续观察5d,Kaplan-Meier生存曲线分析并统计半数致死量(LD50)。结果显示,6个分离株对斑马鱼的LD50在10^5cfu-10^6cfu之间,临床株与非临床株的毒力差异不显著(P〉0.05)。从攻毒后死亡的鱼腹腔和脑可分离到SS2,并伴有腹腔出血及肝、肠、脑部炎性病变。表明SS2可感染斑马鱼,为进一步研究SS2的体内感染机制及毒力因子功能等奠定了基础。 相似文献