全文获取类型
收费全文 | 1066篇 |
免费 | 77篇 |
国内免费 | 2篇 |
专业分类
林业 | 69篇 |
农学 | 82篇 |
基础科学 | 2篇 |
165篇 | |
综合类 | 41篇 |
农作物 | 149篇 |
水产渔业 | 96篇 |
畜牧兽医 | 447篇 |
园艺 | 17篇 |
植物保护 | 77篇 |
出版年
2023年 | 6篇 |
2022年 | 10篇 |
2021年 | 32篇 |
2020年 | 25篇 |
2019年 | 25篇 |
2018年 | 39篇 |
2017年 | 36篇 |
2016年 | 37篇 |
2015年 | 54篇 |
2014年 | 57篇 |
2013年 | 56篇 |
2012年 | 79篇 |
2011年 | 85篇 |
2010年 | 69篇 |
2009年 | 47篇 |
2008年 | 69篇 |
2007年 | 65篇 |
2006年 | 63篇 |
2005年 | 43篇 |
2004年 | 46篇 |
2003年 | 41篇 |
2002年 | 36篇 |
2001年 | 20篇 |
2000年 | 16篇 |
1999年 | 6篇 |
1997年 | 5篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1993年 | 4篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 3篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 2篇 |
1972年 | 3篇 |
1970年 | 1篇 |
1969年 | 1篇 |
1967年 | 4篇 |
1966年 | 9篇 |
1965年 | 4篇 |
1964年 | 1篇 |
1961年 | 2篇 |
1960年 | 2篇 |
1952年 | 1篇 |
1938年 | 1篇 |
排序方式: 共有1145条查询结果,搜索用时 46 毫秒
1.
Verification by polymerase chain reaction of vertical transmission of Theileria sergenti in cows 总被引:2,自引:0,他引:2 下载免费PDF全文
Byeong K. Baek Kim B. Soo Jin H. Kim Jin Hur Bou O. Lee J. M. Jung Misao Onuma Anthony O. Oluoch Chang-Hyun Kim Ibulaimu Kakoma 《Canadian journal of veterinary research》2003,67(4):278-282
To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases. 相似文献
2.
K. Jung Y. Ha S.‐K. Ha D. U. Han D.‐W. Kim W. K. Moon C. Chae 《Zoonoses and public health》2004,51(2):72-76
The aim of these experiments was to investigate the potential antiviral effect of Saccharomyces cerevisiaeβ‐glucan on the pneumonia induced by swine influenza virus (SIV). Forty colostrum‐deprived 5‐day‐old piglets were randomly divided into four groups of 10. The 20 pigs in groups 1 and 2 were administered Saccharomyces cerevisiaeβ‐glucan orally (50 mg/day/pig; En‐Bio Technology Co., Ltd) for 3 days before SIV infection and those in groups 3 and 4 were given culture medium/diluent alone. Groups 1 and 3 were inoculated intranasally with 3 ml of tissue culture fluid containing 2 × 106 tissue culture infective doses 50% (TCID50)/ml of SIV and those in groups 2 and 4 were exposed in the same manner to uninfected cell culture supernatant. The microscopic lung lesions induced by SIV infection (group 1 pigs) were significantly more severe than those induced by infection in animals pre‐administered β‐glucan (group 3) (P < 0.05). Significantly more SIV nucleic acid was detected in the lungs of pigs experimentally infected with SIV only (group 1) at 5, 7 and 10 days post‐inoculation (dpi) compared with lungs from pigs pre‐administered β‐glucan and infected with SIV (group 3) (P < 0.05). The concentrations of interferon‐γ (IFN‐γ) and nitric oxide (NO) in bronchoalveolar lavage fluid from pigs pre‐administered β‐glucan and infected with SIV (group 3) were significantly higher than for any other group at 7 and 10 dpi for IFN‐γ, and at 5, 7 and 10 dpi for NO (P < 0.05). Saccharomyces cerevisiaeβ‐glucan reduced the pulmonary lesion score and viral replication rate in SIV‐infected pigs. These findings support the potential application of β‐glucan as prophylactic/treatment agent in influenza virus infection. 相似文献
3.
Chang‐Hoon Shin Hien Thi Dieu Bui Samad Rahimnejad Ji‐Hoon Cha Byung‐Woo Yoo Bo‐Kyeun Lee Hyung‐Jin Ahn Soo‐Il Choi Yun‐Jeong Choi Yong‐Ho Park Jeong‐Dae Kim Kyeong‐Jun Lee 《Journal of the World Aquaculture Society》2014,45(3):258-268
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets. 相似文献
4.
Soo-Young CHOI Woo-Chang JEONG Young-Won LEE Ho-Jung CHOI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):239-244
Contrast enhanced ultrasound (CEUS) is useful to evaluate tissue perfusion in the kidney. In veterinary
medicine, sedation or anesthesia may be required in uncooperative or panting patients. The aim of this study
was to evaluate and compare the normal kidney perfusion patterns in conscious and anesthetized dogs using
CEUS. Eight healthy beagles were used in this study. Scanning was performed in conscious dogs using manual
restraint (conscious group), or under general anesthesia using tiletamine-zolazepam and medetomidine (TZM
group) or medetomidine (M group). The contrast agent (Sonovue®) was administered as an IV bolus.
The peak intensity (PI), time to peak enhancement from injection (TTP0) and the time to peak
enhancement from the initial rise (TTPup), upslope, downslope and area under the curve (AUC) were
analyzed. Compared to the cortical values in the conscious group, TTP0 was significantly delayed in
the TZM group, and upslope, TTP0 and TTPup were significantly different in the M group.
The AUCs in the TZM and M groups were not different from those in the conscious group. The upslope of renal
medullary perfusion was significantly decreased in the TZM and M groups. TTP0 and TTPup
were also significantly delayed in these groups. The AUC of the medulla was significantly decreased in the M
group. Therefore, TZM is useful as an anesthetic protocol when performing CEUS, and the obtained data may
serve as reference values in the evaluation of renal perfusion using CEUS in dogs under anesthesia. 相似文献
5.
Comparison of Salt and Drought‐Stress Effects on Maize Growth and Yield Formation with Regard to Acid Invertase Activity in the Kernels 下载免费PDF全文
The long‐term effects of salt stress (11 dS m?1) and drought stress (35 % WHC) were investigated for two maize genotypes, focusing on the relation between metabolic changes around the time of pollination and the impact on yield determinants at maturity. The relatively salt‐resistant hybrid Pioneer 3906 and the relatively drought‐resistant hybrid Fabregas were compared. The experiments were conducted in large plastic containers in a vegetation hall in two consecutive years (2011 and 2012). Plant height and leaf area were significantly reduced under both stress conditions. The transpiration rate was only slightly reduced under drought stress; but under salt stress, a significant reduction occurred 40–53 days after sowing. As a significant increase in sucrose concentrations was observed in the salt‐treated maize kernels 2 days after pollination, the availability of assimilates was not limiting and the plants could afford to save water by reduced stomatal opening. Although under both stress conditions the soluble acid invertase activity was reduced 2 days after pollination, concomitantly, an increase in hexose concentrations was observed. Thus, in these experiments, the delivery of hexoses by acid invertase activity did not limit kernel development. Differences in grain yield at maturity between salt and drought stress were most likely caused by salt‐specific effects (Na+ toxicity), Fabregas being more affected than Pioneer 3906. 相似文献
6.
Hyunkyoung LEE Hyeshin HWANG Younghye RO Ji-Hyeon KIM Kyunghyun LEE Eunjin CHOI Youchan BAE Byungjae SO Inhyung LEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(5):869
This study was performed to examine and clarify the cause of hindlimb ataxia and neuropathy seen in the South Korean horse population. Fifty horses diagnosed with hindlimb ataxia and neuropathy were referred for this study. Neurological examination was performed on 47 horses while necropsy was performed in all 50 animals. The occurrence of neurological diseases increased rapidly in the summer and 47 out of 50 horses were referred after the end of July. The incidence of neurological diseases started from the southern part of Korea in July and proceeded northward in August and September. Although there was no correlation with age, Thoroughbred and Warmblood horses showed a higher incidence rate than Halla and Jeju horses. The incidence rate was 5 times higher in geldings than in mares and stallions. Of the 20 cases, 16 were diagnosed with eosinophilic meningoencephalomyelitis in 2015. The most common lesions observed in 2016 were parasitic meningoencephalomyelitis (10 cases, 33%) and eosinophilic meningomyelitis (7 cases, 23%). Histopathological analysis of the brain and spinal cord revealed nematodes of approximately 100–200 µm in diameter, microcavitation and infiltrates of eosinophils, and brown pigmented macrophage infiltrates. The nematodes were identified as Setaria digitata via DNA sequencing, performed subsequent to polymerase chain reaction using DNA isolated from formalin-fixed paraffin-embedded tissue sections of the spinal cord. These results show that aberrant migration of Setaria digitata larva in the brain and spinal cord was a major cause for neurological signs in horses. 相似文献
7.
8.
9.
Shin JH Sakoda Y Kim JH Ochiai K Umemura T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(11):1167-1169
Rabbits were immunized with inactivated influenza virus via the subarachnoidal (SA) or subcutaneous (SC) route, and the antibody titers in cerebrospinal fluid (CSF) and serum were assayed. There were no nervous signs or morphological lesions related to SA immunization. In the SC group, the antibody titer was elevated in serum, but not elevated in CSF. In the SA group, the antibody titer was significantly elevated in serum and even in CSF, and their antibody titers were much greater than in the SC group. The present results suggest that intrathecal immunization is more effective than SC immunization at inducing a protective immune response against the transneural spread of viruses. 相似文献
10.
Park C Yoo JH Jeon HW Kang BT Kim JH Jung DI Lim CY Lee HJ Hahm DH Woo EJ Park HM 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(9):951-955
Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs. 相似文献