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91.
以朱顶红(Hippeastrum vittatum)叶片为外植体进行离体培养,具有取材方便、试材充足、成本低等优势,但叶片诱导再生率极低,是朱顶红离体培养的一大难题。本试验中分别以‘花孔雀’和‘黑天鹅’朱顶红无菌苗叶片为外植体,探究了不同植物生长调节剂和不同取材部位对不定芽诱导和继代增殖的影响。结果表明:最佳外植体为 MS 培养基中培养 10 d 形成的幼嫩叶片基部(0.5 cm),在光照 16 h · d-1(光照强度 36 μmol · m-2 · s-1)下,不定芽诱导的最适培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 2 mg · L-1 TDZ,两个品种的不定芽均以间接途径发生,其中‘花孔雀’在培养 40 d 后形成愈伤组织,55 d形成不定芽,诱导率可达 69.44%;‘黑天鹅’在培养 45 d 后形成愈伤组织,65 d 形成不定芽,诱导率达到 66.67%;最适体细胞胚诱导培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 PIC,‘花孔雀’和‘黑天鹅’的诱导率分别达到 66.67%和 63.89%;最佳不定芽增殖培养基为 MS + 2 mg · L-1 6-BA + 1 mg · L-1 NAA + 1 mg · L-1 TDZ,‘花孔雀’和‘黑天鹅’的增殖系数分别达到 4.67 和 3.46;在不添加植物生长调节剂的 MS培养基中进行生根培养,30 d 后两个品种的生根率均达到 100%;将生根培养 30 d 的小植株转移至室温条件下放置 3 d,摘去封口膜再驯化 3 d 后,移栽至经高温消毒的草炭︰蛭石(体积比)为 1︰1 的基质中,成活率达到 100% 相似文献
92.
Kanichi KUSANO Yuhiro ISHIKAWA Kazuhiro SEKI Ryo KUSUNOSE 《Journal of Equine Science》2008,19(2):25-29
Inflammatory airway disease (IAD) is a common cause of poor performance, interruption of
training and premature retirement in racehorses. It is also reported that up to 80% of
horses are affected at some point in the first years of training in UK and Australia.
However, no studies with regard to the information on occurrence of IAD in Japanese
Thoroughbred racehorses have been reported. To investigate the occurrence and the
characteristics of IAD, epidemic research including endoscopic examination of the airway
tract and trachea wash was conducted for Thoroughbred racehorses presenting coughs or poor
performance which airway tract disease was suspected stalled in training facility managed
by Japan Racing Association. Fifty-six out of 76 Thoroughbred racehorses (73.7%)
presenting coughing or poor performance were diagnosed as IAD. Mean incidence rate of IAD
was 0.3% and it has been confirmed that constant number of IAD exists in Japan. Up to
35.7% of IAD horses showed upper airway abnormalities in some extent. There was a trend
for IAD horses to use wood shavings for bedding and fed hay from the ground compared with
the control group. Therefore, improvement of stabling environment may aid in preventing
IAD. This study demonstrated that Japanese Thoroughbred racehorses are affected by IAD
likewise other countries as well as demonstrated the characteristics of IAD which may
contribute to the clarification of the pathogenesis of IAD. 相似文献
93.
Cytology of tracheal aspirates, tracheal endoscopic and blood tests were carried out to
86 Thoroughbred racehorses presenting coughs or poor performance which were suspected to
have lower respiratory tract disease (LRTD) to assess the conditions of the disorders.
Racehorses were classified into coughing (66 horses) and non-coughing (20 horses) groups
based on clinical symptoms. Nine Thoroughbred racehorses without respiratory abnormality
were used as controls. Assessment of grades of airway mucus, cytology of tracheal
aspirates and serum amyloid A (SAA), fibrinogen (Fbg) and pulmonary surfactant protein D
(SP-D) measurements were performed. Relationships between age, gender and racing careers
were also investigated to understand the characteristics of LRTD in racehorses. Mean age
was significantly higher in non-coughing group compared to coughing group. Existence of
racing career and number of starts were significantly greater in non-coughing group
compared to coughing group. On the other hand, grades of airway mucus were significantly
higher in coughing group compared to control group. Percentages of neutrophils in tracheal
aspirates were significantly higher in coughing group compared to non-coughing and control
groups. SAA, Fbg and SP-D were higher in coughing group compared to non-coughing and
control groups indicating that condition of coughing group is in the acute phase. Positive
rate of inflammatory airway disease was significantly higher in coughing and non-coughing
groups compared to control group. It was concluded that carrying out comprehensive
evaluation including investigation on SAA, Fbg and SP-D analysis with airway assessment to
Thoroughbred racehorses which were suspected to have LRTD are useful procedure to
understand the pathological condition which aid to initiate appropriate treatment,
prognosis judgment or to advise trainers to consider altering training regimen. 相似文献
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98.
AIM: To investigate the expression of p38 mitogen-activated protein kinase (p38MAPK) in the kidney after unilateral ureteral obstruction (UUO) in rats and the functional role of it on apoptosis and fibrosis.METHODS: Eighteen Wistar rats underwent UUO were killed at 3, 7, 14 days. Additional 7 rats were sham operated. Histological changes were observed by HE and Masson staining. Immunohistochemistry study was performed on renal tissue for proliferating cell nuclear antigen (PCNA). Apoptotic cells were determined by terminal deoxynucleotidyl transferase- mediated dUTP nick end labeling (TUNEL) and the electrophoresis analysis of genomic DNA. Western blotting of cysteinyl aspartate specific proteinase-3 (caspase-3), p38MAPK and p-p38MAPK were measured.RESULTS: UUO induced a significant increase in renal tubular and interstitial cell apoptosis, immunohistochemistry of PCNA and Western blotting of caspase-3, p-p38MAPK as well as severe morphology changes. However, there was no significant difference between UUO and the control in Western blotting of p38MAPK.CONCLUSION: An in vivo model of renal fibrosis after UUO demonstrates that activated or phosphorylated p38MAPK plays a role in apoptosis of renal tubulointerstitial cells. 相似文献
99.
Utility of two‐view vs. three‐view abdominal radiography in canines presenting with acute abdominal signs
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Marina V. Mavromatis Mauricio Solano Michael Y. Thelen 《Veterinary radiology & ultrasound》2018,59(4):381-386
There are clear differences in the normal radiographic appearance of the abdominal organs between a left lateral vs. a right lateral view. While a few veterinary academic institutions have transitioned to a three‐view abdominal radiographic study protocol, obtaining only two views of the canine abdomen remains the current standard in veterinary medicine. In this combined retrospective and prospective, case‐controlled study, 48 canine patients presenting with signs of acute abdomen were recruited. Four board‐certified veterinary radiologists and four general practice veterinarians with greater than 3 years of experience in small animal practice were asked to determine if 10 predetermined findings were present within the set of images and if surgery was recommended based on those findings. Image readers were unaware of the clinical history. Three‐view studies did not yield statistically significantly greater accuracy than two‐view studies when evaluating all readers together. No statistically significant associations between the availability of the third view and increased accuracy or confidence were found in evaluations of general practitioners specifically. Evaluation of three‐view radiographic examination, as compared to two‐view examination, did not have perceived or statistically significantly increased diagnostic utility. Based on our findings, there is no statistically increased utility to justify a standard three‐view abdominal radiographic examination over a two‐view study for canines presenting with signs of acute abdomen. 相似文献
100.
Although diagnosis and treatment of horses with colic have improved in the last 30 years, horses with recurrent colic can be a diagnostic and management challenge for both owners and veterinarians, and colic remains a high priority health concern of owners (Mellor et al. 2001 ). Nutritional management of these cases is often based on previous experience combined with recommendations from the evidence‐based literature. This review will briefly summarise the aetiologies of recurrent colic and primarily focus on evidence‐based nutritional management of colonic impactions, sand enteropathy, inflammatory bowel disease, and idiopathic recurrent colic, which is limited. Additional topics to be covered elsewhere in this series that are relevant to this topic include nutritional management of gastric ulceration, liver disease, colitis, geriatric horses, and feeding the horse pre‐ and post surgery. 相似文献