全文获取类型
收费全文 | 202篇 |
免费 | 18篇 |
国内免费 | 15篇 |
专业分类
综合类 | 31篇 |
水产渔业 | 82篇 |
畜牧兽医 | 121篇 |
园艺 | 1篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 14篇 |
2019年 | 7篇 |
2018年 | 6篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 7篇 |
2014年 | 6篇 |
2013年 | 10篇 |
2012年 | 4篇 |
2011年 | 11篇 |
2010年 | 11篇 |
2009年 | 5篇 |
2008年 | 9篇 |
2007年 | 6篇 |
2006年 | 7篇 |
2005年 | 9篇 |
2004年 | 9篇 |
2003年 | 9篇 |
2002年 | 5篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 11篇 |
1996年 | 3篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 10篇 |
1992年 | 2篇 |
1991年 | 4篇 |
1990年 | 5篇 |
1989年 | 10篇 |
1988年 | 3篇 |
1987年 | 1篇 |
1986年 | 2篇 |
排序方式: 共有235条查询结果,搜索用时 47 毫秒
101.
102.
103.
Kazuhiro KENGAKU Tomomi TANAKA Hideo KAMOMAE 《The Journal of reproduction and development》2021,67(5):332
The aim of the present study was to clarify the ovarian and hormonal dynamics after the aspiration of follicular fluid in cows with follicular cysts. Follicular fluid was aspirated from the follicular cysts and follicles that were fated to become cystic follicles and other coexisting normal follicles, respectively, in lactating cows (n = 3). After the aspiration procedure, new follicles developed and reached a diameter of 25 mm without ovulation within 13–19 days. The plasma concentrations of inhibin decreased and follicle-stimulating hormone increased rapidly after the aspiration procedure, and subsequently increased and decreased, respectively, as a new follicle grew. No luteal structures developed after the aspiration procedure, and the animals’ plasma progesterone levels remained low. The present study indicates that the cystic follicles are never luteinized by the aspiration of follicular fluid, and consequently, new follicular cysts are observed to repeatedly develop. 相似文献
104.
采用RT-PCR和cDNA末端快速扩增法(RACE)分离、克隆出鲇(Parasilurus asotus)垂体阿黑皮素原(proopiomelanocortin,POMC)基因全长cDNA序列,共1 099 bp,包括129 bp 5′非翻译区、648 bp阅读框以及322 bp 3′非翻译区,阅读框共编码215个氨基酸,POMC前体蛋白的结构主要由信号肽(Met1-Ala28)、N端多肽(Gln29-Asp102)、促肾上腺皮质激素(ACTH,Ser 105-Met144)、α-黑色素细胞刺激激素(α-MSH,Ser105-Val 117)、促肾上腺皮质激素样中叶肽(CLIP,Arg123-Met144)、γ-促脂解激素(γ-LPH,Glu145-Ser158)、β-黑色素细胞刺激激素(β-MSH,Asp161-Ser177)和β-内啡肽(β-EP,Tyr178-Leu215)构成。分子量计算值为24.66 kD,理论等电点为7.25。同源性分析表明鲇与斑点叉尾的相似性高达88%,其构成多肽中α-MSH、β-MSH、β-EP、CLIP保守性逐渐降低,而γ-MSH、连接肽(JP)、γ-LPH是变异比较大的区域... 相似文献
105.
目的:研究肝硬化患者腺垂体分泌细胞的储备功能。方法:用放免法测定10例男性肝硬化患者行药物腺垂体兴奋试验前后的血清PRL、GH、FSH和LH水平。结果:兴奋腺垂体前与健康对照组比较患者血清GH增高(P〈0.05)、FSH降低(P〈0.05)、LH(P〉0.05)和PRL(P〉0.05)与健康对照组比较差异无显著性,兴奋后垂体激素均值明显低于健康对照组(P值分别为,P〈0.01,P〈0.05,P〈0 相似文献
106.
ABSTRACT: Cultivated eels often either lack a part of the ovary (abnormal) or do not have any gonadal tissue (completely sterile). These abnormalities may cause a failure of induction of sexual maturation of female eels. In order to effectively induce sexual maturation and obtain good quality eggs, female eels having normal ovaries should be selected before induction of maturation. The present study examined effects of injection of salmon pituitary extract (SPE) on serum estradiol-17β levels to estimate gonadal status of sexually immature Japanese eels. At the initial stage (just prior to SPE injection), serum estradiol-17β levels were low and no significant difference was observed among eels possessing the different gonad types (normal, abnormal, and sterile), suggesting that gonadal status cannot be estimated by the measurement of serum estradiol-17β levels. A single injection of SPE significantly increased serum estradiol-17β levels in eels possessing normal and abnormal ovaries, but not in sterile eels. Serum estradiol-17β levels significantly increased from 24 h and were high on day 3. These data indicate that eels possessing ovaries can be distinguished from sterile eels by measurement of serum estradiol-17β between 1 and 3 days after a single injection of SPE. 相似文献
107.
We examined the distribution of the orexin‐like peptides in the pituitary and median eminence of the flat‐tailed house gecko (Hemidactylus platyurus) using immunohistochemistry. Orexin‐B‐like, but not orexin‐A‐like, immunoreactivity was detected in the pituitary, specifically in the pars intermedia, and these cells corresponded to alpha‐melanocyte‐stimulating hormone (αMSH)‐producing cells. Orexin‐B and αMSH secreted from pars intermedia may modulate secretion of adenohypophyseal cells in the pars distalis. In the median eminence, orexin‐B‐immunoreactive puncta and fibres were observed, and these structures corresponded to gonadotropin‐releasing hormone (GnRH)‐immunoreactive puncta and fibres. Orexin‐B secreted from GnRH‐containing neurons in the hypothalamus may affect thyrotropin‐releasing hormone‐containing neurons resulting in modulation of αMSH secretion of melanotrophs in the pars intermedia. 相似文献
108.
109.
110.
R. G. Madrigal F. M. Andrews N. Rademacher R. S. McConnico D. Duplantis S. C. Eades 《Equine Veterinary Education》2018,30(6):295-300
An 8‐year‐old Arabian stallion weighing 361 kg presented to Louisiana State University Veterinary Teaching Hospital with a 3‐month history of weight loss, exercise intolerance, long hair coat and recent history of seizures and aimless wandering in the pasture. An initial presumptive diagnosis of pituitary pars intermedia dysfunction (PPID) was made based on clinical signs. The initial examination revealed weight loss and loss of body condition (BCS 3/9), hypertrichosis, muscle wasting and reluctance to move when prompted. A neurological examination revealed dull mentation with no evidence of proprioceptive deficits in the limbs. Mild hyperglycaemia and a stress leucogram were noted on initial biochemical panel and haematology, respectively. Plasma adrenocorticotrophic hormone (ACTH) concentrations before and after thyrotropin releasing hormone (TRH) stimulation were markedly increased. Rapid slice computed tomography (CT) scan of the head before and after contrast revealed a large mass in the region of the pituitary gland suggestive of macroadenoma causing PPID. Prior to imaging, treatment consisted of supportive nursing care. Due to size of the pituitary gland (measuring 4.6 × 4.6 × 3.8 cm) and the presence of seizure‐like activity and dull mentation, the stallion was subjected to euthanasia. A necropsy was not performed. Pituitary macroadenomas in horses affected with PPID, who show neurological signs such as seizure‐like activity, dull mentation and aimless wandering, might have a poor prognosis and treatment with pergolide mesylate might not reduce pituitary gland size or relieve clinical signs. A CT scan is indicated in horses with neurological signs suspected of PPID to further evaluate pituitary gland size and surrounding structures and rule out other causes to better assess prognosis. 相似文献