全文获取类型
收费全文 | 81篇 |
免费 | 3篇 |
专业分类
林业 | 1篇 |
4篇 | |
综合类 | 22篇 |
农作物 | 2篇 |
水产渔业 | 1篇 |
畜牧兽医 | 43篇 |
植物保护 | 11篇 |
出版年
2021年 | 1篇 |
2019年 | 2篇 |
2018年 | 1篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 1篇 |
2013年 | 2篇 |
2012年 | 2篇 |
2010年 | 4篇 |
2009年 | 6篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2003年 | 5篇 |
2002年 | 9篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 8篇 |
1996年 | 7篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1989年 | 5篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1967年 | 1篇 |
排序方式: 共有84条查询结果,搜索用时 15 毫秒
81.
Assessing the usefulness of B‐mode and colour Doppler sonography,and measurements of circulating progesterone concentrations for determining ovarian responses in superovulated ewes
下载免费PDF全文
![点击此处可从《Reproduction in domestic animals》网站下载免费的PDF全文](/ch/ext_images/free.gif)
MEF Oliveira IF Ribeiro MGK Rodriguez GS Maciel JF Fonseca FZ Brandão PM Bartlewski 《Reproduction in domestic animals》2018,53(3):742-750
The main goal of this study was to assess the usefulness of two imaging modalities, namely the B‐mode and colour Doppler sonography, and serum progesterone (P4) concentrations for determining the ovarian response in superovulated ewes. Twenty‐four sexually mature Santa Inês ewes underwent the superovulatory treatment consisting of eight injections of porcine FSH (total dose of 200 or 133 or 100 mg; n = 8 ewes/total dose) given at 12‐hr intervals and initiated 48 hr before CIDR ® (Pfizer Inc., Auckland, New Zealand) removal. Six days after natural mating, the ovaries of all donor ewes were visualized and examined with transrectal ultrasonography and then with videolaparoscopy to identify and enumerate corpora lutea (CL ) and luteinized unovulated follicles (LUF s). Jugular blood samples were collected just prior to ovarian examinations. The total number of CL (r = .78 and 0.83, p < .0001) and LUF s (r = .74 and 0.90, p < .0001) enumerated using the B‐mode and colour Doppler ultrasonographic technique, respectively, were correlated with that ascertained by videolaparoscopy. Circulating concentrations of P4 were related directly to the number of healthy CL (r = .73, p = .0002) and inversely to the number of prematurely regressing CL (r = ?.46, p = .03), but the accuracy of predicting the number of short‐lived CL with serum P4 concentrations was very poor. The present results indicate that ultrasonographic imaging and serum P4 measurements on the day of embryo recovery are useful indicators of total/normal CL numbers and both ultrasonographic techniques can be used to quantify LUF s in superovulated ewes. 相似文献
82.
A decrease in somatic growth rate, and hence productivity, of the South African west coast rock lobster population which occurred in the late 1980s has had important ramifications for subsequent TACs set for this resource. These are critically dependent on monitoring growth rates and determining whether an increase back towards earlier higher levels is underway. The available data are not well balanced by season and location, and a GLMM approach is used to take account of season–location interactions by treating these as random effects. This results in much less precise estimates of annual somatic growth rate than had been suggested by an earlier fixed effects GLM approach, and has necessitated a change in the philosophy underlying management of the resource. 相似文献
83.
Tolstoy M Cowen JP Baker ET Fornari DJ Rubin KH Shank TM Waldhauser F Bohnenstiehl DR Forsyth DW Holmes RC Love B Perfit MR Weekly RT Soule SA Glazer B 《Science (New York, N.Y.)》2006,314(5807):1920-1922
Two-thirds of Earth's surface is formed at mid-ocean ridges, yet sea-floor spreading events are poorly understood because they occur far beneath the ocean surface. At 9 degrees 50'N on the East Pacific Rise, ocean-bottom seismometers recently recorded the microearthquake character of a mid-ocean ridge eruption, including precursory activity. A gradual ramp-up in activity rates since seismic monitoring began at this site in October 2003 suggests that eruptions may be forecast in the fast-spreading environment. The pattern culminates in an intense but brief (approximately 6-hour) inferred diking event on 22 January 2006, followed by rapid tapering to markedly decreased levels of seismicity. 相似文献
84.
Trouwborst RE Clement BG Tebo BM Glazer BT Luther GW 《Science (New York, N.Y.)》2006,313(5795):1955-1957
Soluble manganese(III) [Mn(III)] has been thought to disproportionate to soluble Mn(II) and particulate Mn(IV)O2 in natural waters, although it persists as complexes in laboratory solutions. We report that, in the Black Sea, soluble Mn(III) concentrations were as high as 5 micromolar and constituted up to 100% of the total dissolved Mn pool. Depth profiles indicated that soluble Mn(III) was produced at the top of the suboxic zone by Mn(II) oxidation and at the bottom of the suboxic zone by Mn(IV)O2 reduction, then stabilized in each case by unknown natural ligands. We also found micromolar concentrations of dissolved Mn(III) in the Chesapeake Bay. Dissolved Mn(III) can maintain the existence of suboxic zones because it can act as either an electron acceptor or donor. Our data indicate that Mn(III) should be ubiquitous at all water column and sediment oxic/anoxic interfaces in the environment. 相似文献