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31.
[目的]观察2味中药复方(LWZY)抗大鼠胃黏膜损伤作用及对血液指标的影响。[方法]采用无水乙醇致大鼠胃黏膜损伤模型、阿司匹林致大鼠胃黏膜损伤模型、盐酸致大鼠胃黏膜损伤模型,预防性灌胃给药,以胃黏膜的损伤指数、凝血酶原时间(PT)、纤维蛋白原(FIB)、活化部分凝血活酶时间(APTT)、凝血酶时间(TT)为指标,评价2味中药复方药剂对各动物模型的抗胃黏膜损伤作用及对血液指标的影响。[结果]西米替丁及LWZY各给药组对阿司匹林大鼠胃黏膜损伤模型、盐酸大鼠胃黏膜损伤模型、无水乙醇大鼠胃黏膜损伤模型均有明显的保护作用,各给药组胃黏膜损伤指数均较模型组明显降低(P0.05;P0.01);无水乙醇模型中的血液值;LWZY组较模型组比较PT、FIB、APTT、TT值有明显降低(P0.05;P0.01),有统计学意义;盐酸模型中的血液值,模型组PT、FIB、APTT、TT值较正常组比较略有升高,LWZY组较模型组比较PT、FIB值有明显降低,但无统计学意义,而APTT、TT值有明显降低(P0.05;P0.01),有统计学意义;阿司匹林模型中的血液指标中模型组PT、FIB、APTT、TT值较正常组比较明显升高,LWZY组较模型组比较PT、FIB、APTT、TT值有明显降低(P0.05;P0.01),有统计学意义。[结论]LWZY对无水乙醇、阿司匹林、盐酸致大鼠胃黏膜损伤有明显的保护作用,并且有一定的体内促凝血作用,作用机制可能和凝血因子以及调节激素水平有关。  相似文献   
32.
在浙粳22辐照的突变体库中,筛选出一个对环境不敏感的全生育期表达的类病斑突变体。遗传分析表明,该突变性状由1对隐性核基因spl(t)控制。利用SSR标记对类病斑突变体spl(t)与珍汕97B杂交构建的F2群体进行基因定位,把spl(t)基因定位在第12号染色体短臂端的着丝粒附近,位于SSR标记RM7195与RM27929之间的0.8cM区间内。锥虫蓝染色检测结果表明spl(t)类病斑的形成和发展是一个程序性细胞死亡的过程。进一步研究表明,这种程序性细胞死亡是由H2O2氧迸发而致。突变体经白叶枯病和稻瘟病鉴定,表明该突变体的抗病性与野生型品种浙粳22相仿。  相似文献   
33.
Intracranial hypertension is a cause of cerebral ischemia and neurologic deficits in dogs. Goals of this retrospective study were to test interobserver agreement for MRI measurements of optic nerve sheath diameter and associations between optic nerve sheath diameter, signalment data, and presumed intracranial hypertension status in a cohort of dogs. A veterinary radiologist interpreted scans of 100 dogs and dogs were assigned to groups based on presence or absence of at least two MRI characteristics of presumed intracranial hypertension. Two observers who were unaware of group status independently measured optic nerve diameter from transverse T2‐weighted sequences. Mean optic nerve sheath diameter for all dogs was 3 mm (1–4 mm). The mean difference between observers was 0.3 mm (limits of agreement, ?0.4 and 1.0 mm). There was no correlation between optic nerve sheath diameter and age for either observer (r = ?0.06 to 0.00) but a moderate positive correlation was observed between optic nerve sheath diameter and body weight for both observers (r = 0.70–0.76). The 22 dogs with presumed intracranial hypertension weighed less than the 78 dogs without (P = 0.02) and were more often female (P = 0.04). Dogs with presumed intracranial hypertension had a larger ratio of optic nerve sheath diameter to body weight for each observer‐side pair (P = 0.01–0.04) than dogs without. Findings indicated that the ratio of MRI optic nerve sheath diameter relative to body weight may be a repeatable predictor of intracranial hypertension in dogs.  相似文献   
34.
长薄鳅恶臭假单胞菌的分离鉴定及其感染的病理损伤   总被引:1,自引:0,他引:1  
恶臭假单胞菌(Pseudomonas putida)是广泛分布于土壤、水体中的一种条件致病菌,可感染两栖类、鱼类和甲壳类等多种水生动物。2017年8月,四川省西昌市某养殖场的长薄鳅出现一种以体表溃烂、鳍条出血为主要特征的传染病。为探究其病因,本研究进行了病原菌分离、人工感染、分离菌表型特征测定、16S rRNA与gyrB基因序列分析。从病鱼肝、脾、肾中分离到优势菌株(BMH170820),人工感染试验证实了其病原性。根据其菌落形态、生理生化特性,结合16S rRNA与gyrB基因序列分析鉴定其为恶臭假单胞菌。组织病理学观察发现,其感染长薄鳅对鳃、肾、肝、心、脾与消化道等多处组织器官造成损伤,表现出明显的变性、坏死和炎症反应,致全身多器官功能障碍而死亡。药物敏感试验显示,该菌对新霉素、氧氟沙星以及强力霉素等敏感,而对阿莫西林、头孢氨苄与氟苯尼考等耐药。  相似文献   
35.
AIM:To observe whether selective inhibition of endothelin receptor A (ETRA) improves white matter lesions (WMLs), and explore the mechanism. METHODS:Sprague-Dawley rats (n=33) were randomly divided into sham operation group (n=9), treatment group[stroke-prone renovascular hypertensive rats-modified 2 vessel occlusion (RHRSP-modified 2VO) + ambrisentan (n=12)] and placebo group[RHRSP-modified 2VO + vehicle (n=12)]. Drug and vehicle administration was performed from 17th to 20th week and monitoring of systolic arterial pressure was performed weekly. Morris water maze test was conducted to evaluate the function of cognition. The protein levels of endothelin-1 (ET-1) in the cortex, corpus callosum and caudate putamen were quantitatively analyzed respectively. The severity of WMLs and the relationship between ET-1 and vessels were observed by the method of histopathology. RESULTS:The difference of systolic arterial pressure between treatment group and placebo group was not significant. The animals in treatment group exhibited shorter escape latency (P<0.05), more times of crossing platform (P<0.05), lower level of ET-1 in corpus callosum and caudate putamen (P<0.05), respectively, improved WMLs severity (P<0.05) and lower binding level of ET-1 to vessels compared with the placebo group. CONCLUSION:Selective inhibition of endothelin receptor A improves the severity of WMLs and ameliorates the cognitive function.  相似文献   
36.
A 3-month-old colt foal presented to the Philip Leverhulme Equine Hospital for investigation of progressive neurological signs. Diagnostic investigation included cerebrospinal fluid collection, which was performed under general anaesthesia. During this procedure, severe bradycardia which progressed to asystole occurred. Initial resuscitation was successful; however, the foal had clinical signs consistent with cerebral hypoxia post-resuscitation and was euthanased the following day due to deterioration of neurological function. Asystole was presumed due to a Cushing-type reflex as a result of changes in intracranial pressure during the sampling procedure.  相似文献   
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Objective

To develop a reference range for ultrasonographically measured optic nerve sheath diameter (ONSD‐US) in dogs. We hypothesized that ONSD‐US can be measured reliably and is associated with weight but not age, sex, or body condition score (BCS), and that the relationship between weight and ONSD‐US in dogs is allometric due to canine size variations.

Design

Prospective, observational study.

Setting

University teaching hospital.

Animals

Seventy‐eight healthy adult dogs.

Interventions

The ONSD was measured by a standardized transpalpebral approach.

Measurements and Main Results

Regression analysis showed the relationship between weight and ONSD was better fit with a linear model (R2 = 0.8510) than an allometric model (R2 = 0.7917). Multiple regression analysis showed ONSD is associated with weight (P < 0.0001), age (P = 0.0021), and BCS (P = 0.0007), but not with sex. Dominance analysis showed 94.6% of the variance explained by the model was due to weight. Intraclass correlation coefficient (ICC) analysis showed excellent interobserver (ICC = 0.9338–0.9608) and intraobserver (ICC = 0.9893) reliability.

Conclusions

These results suggest that ONSD‐US may be reliably measured in dogs using our described transpalpebral approach, and we have calculated prediction intervals based on body weight. Future studies are needed to determine if ONSD‐US measurements are associated with intracranial hypertension as shown in human medicine.  相似文献   
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