首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   290篇
  免费   21篇
  国内免费   1篇
林业   2篇
农学   1篇
基础科学   1篇
  9篇
综合类   11篇
农作物   2篇
水产渔业   3篇
畜牧兽医   277篇
园艺   1篇
植物保护   5篇
  2020年   6篇
  2019年   4篇
  2018年   6篇
  2017年   7篇
  2016年   9篇
  2015年   7篇
  2014年   15篇
  2013年   23篇
  2012年   4篇
  2011年   9篇
  2010年   8篇
  2009年   10篇
  2008年   5篇
  2007年   4篇
  2006年   6篇
  2005年   10篇
  2004年   4篇
  2003年   4篇
  2002年   7篇
  2001年   11篇
  2000年   3篇
  1999年   2篇
  1998年   14篇
  1997年   18篇
  1996年   10篇
  1995年   12篇
  1994年   7篇
  1993年   12篇
  1992年   12篇
  1991年   20篇
  1990年   15篇
  1989年   14篇
  1988年   11篇
  1987年   1篇
  1986年   1篇
  1985年   1篇
排序方式: 共有312条查询结果,搜索用时 15 毫秒
1.
2.
3.
Haematological and biochemical investigations were performed on 14 koalas with uncomplicated cystitis, 8 with complicated cystitis, 8 with conjunctivitis, 8 with lymphosarcoma, and 14 with miscellaneous diseases. Changes were limited and inconsistent in individual koalas with uncomplicated cystitis and conjunctivitis. In contrast, individual koalas with complicated cystitis were more likely to have anaemia, leukocytosis due to neutrophilia, hypoproteinaemia due to hypoalbuminaemia, and azotaemia due to elevated urea concentration. Although these changes were non-specific they did allow assessment of prognosis for survival and response to treatment. Koalas with lymphosarcoma were invariably anaemic, leukaemic, azotaemic and hypoalbuminaemic. Elevated enzymes (aspartate transaminase [AST]. lactate dehydrogenase [LD] and gamma glutamyl transferase [GGT]) were more common in koalas with lymphosarcoma. Koalas affected by miscellaneous conditions showed variable changes but once again anaemia, leukocytosis, azotaemia, elevated AST and LD, and hypoalbuminaemia were not uncommon. On the basis of these findings a minimal profile is suggested for the investigation of sick koalas and would include haematocrit, total and differential leukocyte counts, urea, total protein and albumin concentrations and AST, GGT and LD activities.  相似文献   
4.
5.
6.
7.
The presence and importance of visual oestrous symptoms and the relation to conception, breed, housing system and milk yield were studied. Data were collected from a Swedish research herd during a 16-year period. Local, secondary and primary oestrous symptoms and an overall oestrus intensity score (OI) were studied. Decreasing trends in oestrous expression and conception rates (CR), and an increase in CR with more intensive oestrus, from 24% at OI score one (very week) to 54% at OI score five (very strong) were observed. The mean interval from first to last observed oestrus symptom was long with a large variation (54?±?SD?=?32?h). Generally, irrespectively of housing system, Swedish Red cows had higher CR, more intensive oestruses and longer oestrus durations compared to Swedish Holstein cows. Local oestrous symptoms, with CR of 24–28%, were most frequently detected, which is why more attention should be paid to local oestrous symptoms.  相似文献   
8.
Canine inflammatory mammary cancer (IMC) has been proposed as a model for the study of human inflammatory breast cancer (IBC). The aims of this study were to compare the immunohistochemical expression of aromatase (Arom) and several hormone receptors [estrogen receptor α (ERα), estrogen receptor β (ERβ), progesterone receptor (PR) and androgen receptor (AR)], in 21 IMC cases vs 19 non‐IMC; and to study the possible effect of letrozole on canine IMC and human inflammatory breast cancer (IBC) in vitro using IPC‐366 and SUM‐149 cell lines. Significant elevations of the means of Arom Total Score (TS), ERβ TS and PR TS were found in the IMC group (p = 0.025, p = 0.038 and p = 0.037, respectively). Secondary IMC tumours expressed higher levels of Arom than primary IMC (p = 0.029). Non‐IMC PR‐ tumours contained higher levels of Arom than non‐IMC PR+ tumours (p = 0.007). After the addition of letrozole, the number of IMC and IBC cells dropped drastically. The overexpression of Arom found and the results obtained in vitro further support canine IMC as a model for the study of IBC and future approaches to the treatment of dogs with mammary cancer, and especially IMC, using Arom inhibitors.  相似文献   
9.
Growth and carbon dynamics in mixed grass–red clover leys were simulated using a growth model for pure stands based on radiation use, allocation within plant and loss of biomass. The model and its parameter values were taken from previous applications of the model to pure swards of grass and red clover grown in the same experiment at the same sites and years.  相似文献   
10.
A high-performance liquid chromatographic (HPLC) method for the determination of anthocyanidins from berries and red wine is described. Delphinidin, cyanidin, petunidin, pelargonidin, peonidin, and malvidin contents of bilberry (Vaccinium myrtillus), black currant (Ribes nigrum), strawberry (Fragaria ananassa cv. Jonsok), and a Cabernet sauvignon (Vitis vinifera) red wine were determined. The aglycon forms of the anthocyanins present in the samples were revealed by acid hydrolysis. A reversed phase analytical column was employed to separate the anthocyanidins before identification by diode array detection. The suitability of the method was tested by determining the recovery (95-102% as aglycons and 69-104% from glycosides) for each anthocyanidin. Method repeatability was tested by charting the total aglycon content of two samples over a period of 14 analyses and determining the coefficients of variation (1.41% for bilberry and 2.56% for in-house reference material). The method developed proved thus to be effective for reliable determination of anthocyanidins from freeze-dried berry samples and red wine. The total anthocyanidin content of the tested samples was as follows: in-house reference material, 447 +/- 8 mg/100 g; strawberry, 23.8 +/- 0.4 mg/100 g; black currant, 135 +/- 3 mg/100 g; bilberry, 360 +/- 3 mg/100 g; and Cabernet sauvignon red wine, 26.1 +/- 0.1 mg/100 mL.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号