全文获取类型
收费全文 | 8269篇 |
免费 | 3594篇 |
国内免费 | 4篇 |
专业分类
林业 | 241篇 |
农学 | 458篇 |
1511篇 | |
综合类 | 527篇 |
农作物 | 149篇 |
水产渔业 | 2624篇 |
畜牧兽医 | 4986篇 |
园艺 | 49篇 |
植物保护 | 1322篇 |
出版年
2023年 | 18篇 |
2022年 | 18篇 |
2021年 | 177篇 |
2020年 | 520篇 |
2019年 | 1066篇 |
2018年 | 938篇 |
2017年 | 988篇 |
2016年 | 971篇 |
2015年 | 858篇 |
2014年 | 851篇 |
2013年 | 1038篇 |
2012年 | 589篇 |
2011年 | 629篇 |
2010年 | 672篇 |
2009年 | 305篇 |
2008年 | 364篇 |
2007年 | 232篇 |
2006年 | 221篇 |
2005年 | 255篇 |
2004年 | 208篇 |
2003年 | 229篇 |
2002年 | 235篇 |
2001年 | 81篇 |
2000年 | 104篇 |
1999年 | 16篇 |
1998年 | 23篇 |
1997年 | 21篇 |
1996年 | 13篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1993年 | 14篇 |
1991年 | 8篇 |
1990年 | 12篇 |
1989年 | 8篇 |
1986年 | 10篇 |
1985年 | 7篇 |
1984年 | 6篇 |
1983年 | 5篇 |
1982年 | 8篇 |
1981年 | 8篇 |
1980年 | 5篇 |
1978年 | 10篇 |
1977年 | 13篇 |
1976年 | 7篇 |
1975年 | 8篇 |
1974年 | 5篇 |
1970年 | 6篇 |
1968年 | 4篇 |
1966年 | 5篇 |
1963年 | 4篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
121.
122.
123.
124.
Thomas R. De Ridder Justine E. Campbell Cheryl Burke‐Schwarz David Clegg Emily L. Elliot Samuel Geller Wendy Kozak Stephen T. Pittenger Jennifer B. Pruitt Jocelyn Riehl Julie White Melissa L. Wiest Chad M. Johannes John Morton Pamela D. Jones Peter F. Schmidt Victoria Gordon Paul Reddell 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2021,35(1):415-429
125.
126.
127.
The stratum corneum (SC), the outermost layer of the epidermis, serves a crucial role in maintaining body hydration and protection from environmental insults. When the stratum corneum is injured or when the genetic blueprints are flawed, the body is at risk of dehydration, secondary infections and allergen sensitization. Advancements in veterinary dermatology have revealed a wide gamut of disease from relatively benign to lethal that specifically arise from flawed structural proteins, enzymes or lipids needed to create the corneocytes and lipid bilayers of the SC. Some conditions closely mimic their human counterparts while others are unique to the dog. This review will focus on forms of ichthyosis in the dog. 相似文献
128.
Kelsey T. Young Kevin K. Lahmers Holly S. Sellers David E. Stallknecht Rebecca L. Poulson Jerry T. Saliki Stephen Mark Tompkins Ian Padykula Chris Siepker Elizabeth W. Howerth Michelle Todd James B. Stanton 《Journal of veterinary diagnostic investigation》2021,33(2):202
RNA viruses rapidly mutate, which can result in increased virulence, increased escape from vaccine protection, and false-negative detection results. Targeted detection methods have a limited ability to detect unknown viruses and often provide insufficient data to detect coinfections or identify antigenic variants. Random, deep sequencing is a method that can more fully detect and characterize RNA viruses and is often coupled with molecular techniques or culture methods for viral enrichment. We tested viral culture coupled with third-generation sequencing for the ability to detect and characterize RNA viruses. Cultures of bovine viral diarrhea virus, canine distemper virus (CDV), epizootic hemorrhagic disease virus, infectious bronchitis virus, 2 influenza A viruses, and porcine respiratory and reproductive syndrome virus were sequenced on the MinION platform using a random, reverse primer in a strand-switching reaction, coupled with PCR-based barcoding. Reads were taxonomically classified and used for reference-based sequence building using a stock personal computer. This method accurately detected and identified complete coding sequence genomes with a minimum of 20× coverage depth for all 7 viruses, including a sample containing 2 viruses. Each lineage-typing region had at least 26× coverage depth for all viruses. Furthermore, analyzing the CDV sample through a pipeline devoid of CDV reference sequences modeled the ability of this protocol to detect unknown viruses. Our results show the ability of this technique to detect and characterize dsRNA, negative- and positive-sense ssRNA, and nonsegmented and segmented RNA viruses. 相似文献
129.
Kara L. Moreno Elizabeth M. Scallan Beatriz P. Monteiro Paulo V. Steagall Bradley T. Simon 《Veterinary anaesthesia and analgesia》2021,48(4):570-576
ObjectiveTo evaluate the thermal antinociceptive effects of a high-concentration formulation of buprenorphine alone or followed by hydromorphone in conscious cats.Study designRandomized, blinded, placebo-controlled crossover study design.AnimalsA total of six purpose-bred, adult female ovariohysterectomized Domestic Short Hair cats.MethodsCats were allocated into three treatments each consisting of two injections, subcutaneous then intravenous (IV) administration, 2 hours apart: treatment SS, two injections of 0.9% saline; treatment BS, buprenorphine (0.24 mg kg–1, 1.8 mg mL–1) and saline; and treatment BH, buprenorphine (0.24 mg kg–1) and hydromorphone (0.1 mg kg–1). Skin temperature (ST) and thermal threshold (TT) were recorded before (baseline) and for 24 hours following first injection. TT data were analyzed using mixed linear models and a Benjamini–Hochberg sequential adjustment procedure (p < 0.05).ResultsThere were no significant differences among treatments for baseline ST and TT values, treatment SS over time and between treatments BS and BH. Compared with baseline, TT was significantly increased at all time points in treatments BH and BS except at 2 hours in treatment BS. TT was significantly higher than SS at 3–18 hours and 4–12 hours for treatments BS and BH, respectively. Maximal increases in TT were 47.5 °C at 2 hours, 53.9 °C at 3 hours and 52.4 °C at 6 hours in treatments SS, BS and BH, respectively.Conclusions and clinical relevanceAdministration of IV hydromorphone following high-concentration buprenorphine provided no additional antinociception and decreased the duration of effect when compared with high-concentration buprenorphine alone. Alternative analgesics should be considered if additional analgesia is required after administration of high-concentration buprenorphine. 相似文献
130.
Wei‐Shan Lee Jih‐Jong Lee Albert Taiching Liao Chia‐Lien Kao Shang‐Lin Wang 《Veterinary and comparative oncology》2021,19(1):53-60
The majority of the known prognostic factors in dogs with lymphoma have been evaluated before treatment commences or at the time of diagnosis. Prognostic factors evaluated during the initial phase of treatment are less described but may provide important clinical information. In this retrospective study, 82 canine lymphoma patients were categorized according to the weight change between diagnosis and after 5 weeks of chemotherapy. Dogs that gained greater than 5% or lost greater than 5% of initial body weight were categorized as increased‐ or decreased‐weight groups, respectively. Those in which weight changed less than 5% were categorized as the maintained‐weight group. The median progression‐free survival (PFS) in the increased‐weight group, maintained‐weight group and decreased‐weight group was 226, 256 and 129 days, respectively. The decreased‐weight group had significantly shorter PFS than the increased and maintained groups (P = .023, P = .003, respectively). The median survival time (ST) in the increased‐weight group, maintained‐weight group and decreased‐weight group was 320, 339 and 222 days, respectively. There was no significant difference in ST among the three groups (P = .128). In Cox‐regression results, weight change group and initial body weight were significant risk factors associated to PFS (P = .007, P = .001, respectively) while only patient's initial body weight was a significant risk factor to ST (P = .013). In conclusion, evaluation of initial body weight and weight changes over time can provide valuable information regarding PFS and ST in dogs with multicentric lymphoma. 相似文献