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31.
MRI诊断双侧基底节区对称性分水岭脑梗死   总被引:1,自引:0,他引:1  
目的:探讨双侧基底节区对称性分水岭性脑梗死(CWI)的病因与机理、MRI特征。方法:回顾性分析12例经MRI及临床证实的双侧基底节区对称性CWI的临床资料及MRI表现。结果:12例的病因中以严重低血压及低血容量为主,MRI表现为双侧基底节区对称性T1WI为低,T2WI为高信号,信号均匀,占位不明显,加强扫描无强化。结论:双侧基底节区对称性CWI病因主要为严重低血压及低血容量。MRI能较早及敏感地显示其变化,其与一些好发于基底节区病变的MRI表现相似,鉴别时须结合临床资料。  相似文献   
32.
骨髓间充质干细胞移植治疗脑缺血的动物实验研究   总被引:1,自引:0,他引:1       下载免费PDF全文
    探讨骨髓间充质干细胞(MSCs)移植对大鼠脑缺血的修复和治疗.体外分离培养大鼠MSCs,以Hoeschst33342标记,移植到大脑中动脉梗塞(MCAO)模型的大鼠体内,分别设立缺血1 d和缺血7 dMSCs移植组与缺血对照组,对各组大鼠进行神经功能损害严重程度评分(NSS)及大脑组织切片观察比较.结果发现,缺血1 d MSCs移植组大鼠NSS评分低于另外两组,差异显著(P<0.05),大脑组织结构清晰、完整,胶质瘢痕少;缺血7 d MSCs移植组与对照组无明显差异(P>0.05).故缺血早期进行MSCs移植,大鼠神经功能恢复情况明显.MSCs在损伤后的脑组织内能够存活并且分化为神经元、胶质细胞等,对动物神经损伤后组织重建及功能恢复有一定的治疗作用.  相似文献   
33.
目的 观察“四海之腧”取穴法对脑梗塞恢复期患者的血脂水平及凝血系统的影响。方法 将60例患者随机分为治疗组和对照组,每组各30例。两组患者均接受基础治疗,治疗组配合“四海之腧”取穴法,对照组配合常规针刺,3个疗程后,观察治疗前后血脂及凝血系统相关指标情况。结果 两组患者治疗前后血脂水平和凝血系统指标比较差异均有统计学意义(P<0.05),且治疗组疗效优于对照组(P<0.05)。结论 “四海之腧”取穴法可调节脑梗塞恢复期患者的血脂水平及血液流变学状态,疗效确切,值得临床推广应用。  相似文献   
34.
格尔木紫皮大蒜种植的气候条件分析   总被引:1,自引:0,他引:1  
利用格尔木气象观测资料,分析了格尔木的气候特征,根据紫皮大蒜的生长特征和对气象条件的要求,分析了紫皮大蒜种植的农业气象条件,提出建立适宜气候条件下的科学管理模式,发展紫皮大蒜种植产业。  相似文献   
35.
目的 观察四海之腧取穴法配合康复训练治疗脑梗死恢复期的临床疗效。方法 将60例患者随机分为治疗组和对照组各30例,两组患者均接受基础治疗,治疗组采取四海之腧取穴法结合常规康复训练,对照组采用常规针刺结合康复训练,1个月为1个疗程,治疗3个疗程后,观察治疗前后上下肢Fugl-Meyer评分、NIHSS评分变化情况。结果 与治疗前相比,两组治疗1个月、2个月和3个月后Fugl-Meyer评分、NIHSS评分均有所改善(P<0.05或P<0.01),且治疗组各项指标均显著优于对照组,尤以治疗组治疗3个月后疗效为最佳(P<0.01)。结论 “四海之腧”取穴法结合康复训练的治疗方式可更好地改善脑梗死恢复期患者的运动功能障碍和神经功能缺损情况,疗效确切,值得临床推广应用。  相似文献   
36.
AIM: To investigate the role of excitatory amino acid transporter 3(EAAT3) in prefrontal cortex and hippocampus in morphine relapse by detecting the changes of EAAT3 expression in prefrontal cortex and hippocampus in conditioned place preference (CPP) reinstatement rat model induced by morphine.METHODS: Forty adult male SD rats, weighing 200-250 g, were randomly divided into 5 groups with 8 rats each: control group, CPP establishment group (Es), CPP extinction group (Ex), reinstatement 2 h group (Re2) and reinstatement 4 h group (Re4).Intraperitoneal (ip) injection of morphine was applied at a constant dose (10 mg/kg) for 10 days to the established CPP model.Normal saline instead of morphine was used to induce CPP extinction for 10 days.CPP was reinstated following a single priming injection of morphine (2.5 mg/kg).After the CPP behavior test, the rats were sacrificed, and the prefrontal cortex and hippocampus were collected for detecting the levels of EAAT3 by Western blotting.RESULTS: The accumulated time the rats spent in the drug-paired chamber was significantly longer in Es group, Re2 group and Re4 group than that in control group (P<0.05).Compared with control group, the expression of EAAT3 in prefrontal cortex significantly decreased both in Es group and Re4 group (P<0.05).No significant change of EAAT3 in hippocampus among groups was observed (P>0.05), while EAAT3 in hippocampal CA1 area significantly increased in Es group and Ex group as compared with control group (P<0.05).CONCLUSION: The expression of EAAT3 in prefrontal cortex decreases both in CPP establishment and reinstatement models, indicating that down-regulation of EAAT3 in prefrontal cortex may partly participate in the formation of opium relapse.  相似文献   
37.
探讨了3种常用的有机磷农药胚胎期暴露对新生鼠脑组织结构的影响。在母鼠妊娠期7.5~11.5 d时,连续5 d每天分别经皮下注射2 mg/kg bw的二嗪磷(diazinon)、2 mg/kg bw的毒死蜱(chlorpyrifos)及50 mg/kg bw乙酰甲胺磷(acephate),显微镜下观察并计数大脑皮层S1区胶质细胞和神经元数量及比率,以及海马CA1、CA3区锥体细胞的数量及体积密度。结果表明,二嗪磷与毒死蜱处理分别使得大脑皮层S1区胶质细胞数减少了14.29%和21.43%;毒死蜱处理导致胶质细胞与神经元比率下降了24.19%;二嗪磷与毒死蜱处理后海马CA1区锥体细胞数量分别下降了9.30%与20.93%,毒死蜱处理后锥体细胞体积密度下降了27.05%;二嗪磷与毒死蜱处理后海马CA3区锥体细胞数量分别下降了22.22%和19.44%,锥体细胞体积密度分别下降了23.54%和18.98%;而乙酰甲胺磷对新生鼠大脑皮层与海马细胞均无明显影响。  相似文献   
38.
A new of performing cerebral sinus venography was developed that opacivies both the ventral and most of the dorsal venous sinus systems. A pediatric angiographic catheter was introduced into the external jugular vein and advanced to the level of the temporal sinus. Iodinated contrast medium was injected manually and radiographs were made. Subtraction radiography was used to visualize vessels field wit contast medium. Venography was simple and relatively non-invasive and was considered safe. The technique was used to confirm occlusion of the transverse venous sinus in healthy dogs that had undergone radical craniectomies.  相似文献   
39.
AIM:To explore the molecular effects of Astragalus polysaccharide(AP) on improving nervous functions and preventing neuronal apoptosis in rat cerebral cortex with cerebral ischemia and reperfusion. METHODS:One hundred and twenty male Wister rats were randomly divided into sham operation group(SOG), model groups(MG-1 d, 3 d and 7 d), low-dose AP treatment groups(L-APTG-1 d, 3 d and 7 d), and high-dose AP treatment groups(H-APTG-1 d, 3 d and 7 d). The right middle cerebral artery of the rats in MG and AGTG was intercepted by operation to induce ischemic brain injury. The rats in L-APTG and H-APTG were treated with AP at the doses of 5 mg/kg and 15 mg/kg by intraperitoneal injection, respectively. On the 1st day, 3rd day and 7th day after operation, those animals were sacrificed to collect the brain specimens for the study after cerebral blood flow reperfusion and determination of neurological deficit scores. The structural changes of the neurons were observed under electron microscope. Apoptosis was analyzed by flow cytometry. The protein levels of heat-shock protein 70(HSP70), protein kinase B(PKB) and P53 in cerebral corical neurons were determined by immunohistochemical staining and Western blotting. RESULTS:The neurological deficit scores and the apoptotic rate of cerebral cortical neurons in H-APTG were significantly lower than those in MG and L-APTG(P<0.05). The structures of the neurons in H-APTG, such as ribosome endoplasmic reticulum, nucleolus, Golgi complex, mitochondria, etc, were better than those in MG and L-APTG. On the 1st day, 3rd day and 7th day, the protein levels of HSP70 and PKB in cerebral cortical neurons in H-APTG were significantly higher than those in L-APTG, which were significantly higher than those in MG(P<0.05). However, the P53 protein level in H-APTG was significantly lower than that in L-APTG, which was significantly lower than that in MG(P<0.05). CONCLUSION:AP improves nervous functions and inhibits neuronal apoptosis during ischemia and reperfusion. The molecular mechanisms are associated with variations of protein expression in cerebral cortical neurons, such as promotion of HSP70 and PKB and inhibition of P53.  相似文献   
40.
Reasons for performing study: Minocycline holds great potential for use in horses not only for its antimicrobial effects but also for its anti‐inflammatory and neuroprotective properties. However, there are no pharmacokinetic or safety data available regarding the use of oral minocycline in horses. Objectives: To determine pharmacokinetics, safety and penetration into plasma, synovial fluid, aqueous humour (AH) and cerebral spinal fluid (CSF) of minocycline after oral administration of multiple doses in horses and to determine the minimum inhibitory concentrations (MIC) of minocycline for equine pathogenic bacteria. Methods: Six horses received minocycline (4 mg/kg bwt q. 12 h for 5 doses). Thirty‐three blood and 9 synovial fluid samples were collected over 96 h. Aqueous humour and CSF samples were collected 1 h after the final dose. Minocycline concentrations were measured using high pressure liquid chromatography. The MIC values of minocycline for equine bacterial isolates were determined. Results: At steady state, the mean ± s.d. peak concentration of minocycline in the plasma was 0.67 ± 0.26 µg/ml and the mean half‐life was 11.48 ± 3.23 h. The highest trough synovial fluid minocycline concentration was 0.33 ± 0.12 µg/ml. The AH concentration of minocycline was 0.09 ± 0.03 µg/ml in normal eyes and 0.11 ± 0.04 µg/ml in blood aqueous barrier‐disrupted eyes. The mean CSF concentration of minocycline was 0.38 ± 0.09 µg/ml. The MIC values were determined for 301 isolates. Minocycline concentrations were above the MIC50 and MIC90 for many gram‐positive equine pathogens. Potential relevance: This study supports the use of orally administered minocycline at a dose of 4 mg/kg bwt every 12 h for the treatment of nonocular infections caused by susceptible (MIC≤0.25 µg/ml) organisms in horses. Further studies are required to determine the dose that would be effective for the treatment of ocular infections.  相似文献   
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