全文获取类型
收费全文 | 4286篇 |
免费 | 278篇 |
国内免费 | 2篇 |
专业分类
林业 | 387篇 |
农学 | 187篇 |
基础科学 | 30篇 |
1116篇 | |
综合类 | 301篇 |
农作物 | 208篇 |
水产渔业 | 344篇 |
畜牧兽医 | 1544篇 |
园艺 | 61篇 |
植物保护 | 388篇 |
出版年
2023年 | 59篇 |
2022年 | 53篇 |
2021年 | 112篇 |
2020年 | 126篇 |
2019年 | 62篇 |
2018年 | 179篇 |
2017年 | 185篇 |
2016年 | 183篇 |
2015年 | 145篇 |
2014年 | 178篇 |
2013年 | 285篇 |
2012年 | 374篇 |
2011年 | 343篇 |
2010年 | 168篇 |
2009年 | 119篇 |
2008年 | 283篇 |
2007年 | 274篇 |
2006年 | 235篇 |
2005年 | 240篇 |
2004年 | 185篇 |
2003年 | 200篇 |
2002年 | 157篇 |
2001年 | 87篇 |
2000年 | 77篇 |
1999年 | 40篇 |
1998年 | 20篇 |
1997年 | 18篇 |
1996年 | 9篇 |
1995年 | 9篇 |
1994年 | 12篇 |
1993年 | 16篇 |
1992年 | 8篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 7篇 |
1987年 | 4篇 |
1985年 | 6篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 4篇 |
1976年 | 4篇 |
1974年 | 5篇 |
1969年 | 4篇 |
1968年 | 5篇 |
1953年 | 3篇 |
1937年 | 2篇 |
1934年 | 3篇 |
排序方式: 共有4566条查询结果,搜索用时 93 毫秒
1.
Ana E. González-Santiago Belinda Vargas-Guerrero Pedro M. García-López Alma L. Martínez-Ayala José A. Domínguez-Rosales Carmen M. Gurrola-Díaz 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(2):134-140
Lupinus albus seeds contain conglutin gamma (Cγ) protein, which exerts a hypoglycemic effect and positively modifies proteins involved in glucose homeostasis. Cγ could potentially be used to manage patients with impaired glucose metabolism, but there remains a need to evaluate its effects on hepatic glucose production. The present study aimed to analyze G6pc, Fbp1, and Pck1 gene expressions in two experimental animal models of impaired glucose metabolism. We also evaluated hepatic and renal tissue integrity following Cγ treatment. To generate an insulin resistance model, male Wistar rats were provided 30% sucrose solution ad libitum for 20 weeks. To generate a type 2 diabetes model (STZ), five-day-old rats were intraperitoneally injected with streptozotocin (150 mg/kg). Each animal model was randomized into three subgroups that received the following oral treatments daily for one week: 0.9% w/v NaCl (vehicle; IR-Ctrl and STZ-Ctrl); metformin 300 mg/kg (IR-Met and STZ-Met); and Cγ 150 mg/kg (IR-Cγ and STZ-Cγ). Biochemical parameters were assessed pre- and post-treatment using colorimetric or enzymatic methods. We also performed histological analysis of hepatic and renal tissue. G6pc, Fbp1, and Pck1 gene expressions were quantified using real-time PCR. No histological changes were observed in any group. Post-treatment G6pc gene expression was decreased in the IR-Cγ and STZ-Cγ groups. Post-treatment Fbp1 and Pck1 gene expressions were reduced in the IR-Cγ group but increased in STZ-Cγ animals. Overall, these findings suggest that Cγ is involved in reducing hepatic glucose production, mainly through G6pc inhibition in impaired glucose metabolism disorders. 相似文献
2.
de Almeida Márcia Rodrigues Schwambach Joséli Silveira Vanildo Heringer Angelo Schuabb Fett Janette Palma Fett-Neto Arthur G. 《New Forests》2020,51(2):213-241
New Forests - Adventitious rooting (AR) is an obligatory step for vegetative propagation of commercial woody species. Paper industries have interest in Eucalyptus globulus Labill and its hybrids... 相似文献
3.
Raquel Lucas-González Manuel Viuda-Martos José Ángel Pérez-Álvarez Juana Fernández-López 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(1):67-73
The aim of the work was to study the influence of particle size in the composition, physicochemical, techno-functional and physio-functional properties of two flours obtained from persimmon (Diospyros kaki Trumb. cvs. ‘Rojo Brillante’ (RBF) and ‘Triump’ (THF) coproducts. The cultivar (RBF and THF) and particle size significantly affected all parameters under study, although depending on the evaluated property, only one of these effects predominated. Carbohydrates (38.07–46.98 g/100 g) and total dietary fiber (32.07–43.57 g/100 g) were the main components in both flours (RBF and THF). Furthermore, insoluble dietary fiber represented more than 68% of total dietary fiber content. All color properties studied were influenced by cultivar and particle size. For both cultivars, the lower particle size, the higher lightness and hue values. RBF flours showed high values for emulsifying activity (69.33–74.00 mL/mL), while THF presented high values for water holding capacity (WHC: 9.47–12.19 g water/g sample). The bile holding capacity (BHC) and fat/oil binding values were, in general, higher in RBF (19.61–12.19 g bile/g sample and 11.98–9.07, respectively) than THF (16.12–12.40 g bile/g sample and 9.78–7.96, respectively). The effect of particle size was really evident in both WHC and BHC. Due to their dietary fiber content, techno-functional and physio-functional properties, persimmon flours seem to have a good profile to be used as potential functional ingredient. 相似文献
4.
5.
Morin M Sauvageau R Phaneuf JB Teuscher E Beauregard M Lagacé A 《The Canadian veterinary journal. La revue veterinaire canadienne》1984,25(12):440-442
Necropsy records of 36 sows with torsion of abdominal organs involving individually the stomach, the spleen, a liver lobe or the intestine were reviewed for the years 1970 to 1983, and the age, the clinical signs and the gross lesions were recorded. These acute abdominal accidents were characterized clinically by sudden death. Dry sows from large breeding units were affected. Twenty-six cases were diagnosed between January 1981 and December 1983 while only ten cases had been seen between 1970 and 1980. Gastric torsion was the most common condition (40% of the cases) and the other three conditions were equally represented (20% each). Management practises that could be responsible for the apparent increase in occurrence of this problem are discussed. 相似文献
6.
Transitional Cell Carcinoma of the Urinary Bladder in a Beluga Whale (Delphinapterus leucas) 总被引:1,自引:0,他引:1 下载免费PDF全文
Martineau D Lagacé A Massé R Morin M Béland P 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(10):297-302
A transitional cell carcinoma of the urinary bladder was found in a beluga whale stranded in the St. Lawrence middle estuary. Various organs of this animal were submitted to high resolution gas chromatography coupled with mass spectrometry analysis. High frequency of urinary bladder cancer in the human population of the same area and the presence of carcinogenic compounds in the marine environment of this animal are discussed.
Concurrent isolation of Edwardsiella tarda from various organs of this whale is also reported.
相似文献7.
Summary On two occasions an anaplasm was isolated from sheep on the Dutch island of Ameland. The organism proved to be highly pathogenic for splenectomised sheep; a non-splenectomised animal recovered spontaneously after the packed cell volume had decreased by 40%. Treatment with oxytetracycline was effective. Its pathogenicity for goats appeared to be low, and the organism was apparently not infective to splenectomised cattle. This anaplasm differs from Anaplasma ovis in that less than 30% of the organisms are marginally situated in the red cell, as against over 70% in A. ovis; cross-immunity with A. ovis was incomplete and the latter appeared to be far more pathogenic to goats than the Dutch anaplasm, for which the name Anaplasma mesaeterum sp.n. is proposed. Its ultrastructure is similar to that of A. marginale and A. ovis. The vector is either Ixodes ricinus or Haemaphysalis punctata. Its practical importance remains to be ascertained. 相似文献
8.
Dr. L. Bos Dr. M. P. Benetti 《European journal of plant pathology / European Foundation for Plant Pathology》1979,85(6):241-251
Most of 43 viruses could easily be detected directly in 53 out of 66 leaf samples dried and stored over CaCl2 for varying periods of time up to 20 1/2 years. Detection usually was with PTA pH 6.5, but alfalfa mosaic, cucumber mosaic and tomato aspermy viruses required PTA pH 3.0 to 4.0. Bean common mosaic, cowpea aphid-borne mosaic and cowpea mosaic viruses were also easily observed in newly dehydrated samples obtained for diagnosis from Morocco and Tanzania.Broad bean wilt virus, cowpea mosaic virus and cucumber mosaic virus were detected with agar gel-diffusion tests in dry leaf material ground in buffer. This serological assay demonstrated a high concentration of cucumber mosaic virus in leaf material dried over CaCl2 20 years ago. This paper further coroborates the value of the CaCl2 method of dehydration and storage of plant viruses in leaf material.Samenvatting Zeer uiteenlopende plantevirussen kunnen goed worden bewaard in bladmateriaal van geïnfecteerde planten dat is gedroogd en bewaard boven CaCl2. Bij rechtstreekse elektronenmicroscopische toetsing van 66 monsters met verschillende isolaten van 43 virussen konden in 53 monsters gemakkelijk virusdeeltjes worden waargenomen (Tabel 1 en Fig. 1 en 2). Meestal lukte dit met fosforwolfraamzuur pH 6,5 dat doorgaans voor in ruw plantesap voorkomende virussen wordt gebruikt. Bij luzernemozaïekvirus en komkommermozaïek virus gelukte dit alleen maar bij lagere pH (3,0 en 4,0). Ook het tomate-aspermievirus was dan veel gemakkelijker aantoombaar. Methylaminewolfraamzuur gaf geen beter resultaat.Draden van bonerolmozaïekvirus en van cowpea aphid-borne mosaic virus en bolletjes van cowpea mosaic virus waren snel waarneembaar in elektronenmicroscopische preparaten gemaakt van bladmateriaal van recent uit Marokko en Tanzania ontvangen monsters.Cowpea mosaic virus, tuinboneverwelkingsvirus en komkommermozaïekvirus konden eveneens gemakkelijk en snel serologisch worden aangetoond in met bufferoplossing vermalen droog blad van respectievelijk cowpea, erwt en tabak. Het laatstgenoemde, reeds 20 1/2 jaar geleden gedroogde bladmateriaal, bleek in vergelijking met pas geïnoculeerd vers blad van komkommer enChenopodium quinoa zelfs zeer veel serologisch actief virusmateriaal te bevatten (Fig. 3).De beschreven waarnemingen bevestigen nogmaals de waarde van de toegepaste methode van virusbewaring en tonen aan dat het mogelijk is vele virussen te herkennen in van elders ontvangen gedroogde bladmonsters, zonder het risico te lopen van virusontsnapping, zoals altijd aanwezig bij werk met toetsplanten in de kas.Guestworker from Istituto Sperimentale per la Patologia Vegetale, Rome, Italy, participating in the investigations from September 21 to December 21, 1977. 相似文献
9.
Corné M. J. Pieterse Pierre J. G. M. de Wit Francine P. M. Govers 《European journal of plant pathology / European Foundation for Plant Pathology》1992,98(Z2):85-92
The fungal pathogenPhytophthora infestans is the causal organism of late blight, one of the most devastating diseases of potato. In the past, various aspects of the potato-P. infestans interaction have been studied extensively. In this paper we briefly review the current knowledge of the molecular events associated with the interaction and in addition we discuss a new approach for analyzing the molecular basis of pathogenicity ofP. infestans. 相似文献
10.