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71.
套袋梨园应侧重于对枝干、叶部病虫害及人袋害虫的防治。选择高效、低毒、低残留、低药害的农药种类,同时要避免用药种类单一,以防病虫产生抗药性。在防治方法上,应坚持“综合防治”,本着“预防为主,治疗为辅”的原则。要注意保护天敌,选用对天敌无害的生物农药,在天敌发生高峰期不用药。强化农业措施防治、生物防治和人工防治。注意“三个结合”,即杀菌剂和杀虫剂相结合,防病虫药剂与叶面施肥相结合,药剂与助剂(多功能植物增效剂、展着剂等)相结合。  相似文献   
72.
荷兰豆系采收嫩荚的食用荚豌豆,风味独特,色泽鲜绿,深受国际市场的欢迎.我地从1992年开始引进试种,现已形成近2万亩的生产规模.经技术人员的不断探索,已掌握一套行之有效适宜淮北地区的高产栽培技术,现将有关技术要点介绍如下:  相似文献   
73.
试验将槐花蜂花粉进行振动磨超微粉碎破壁,分别按1 g/kg、5 g/kg、10 g/kg三个不同剂量混到蛋鸡饲料中,从7日龄开始饲喂至50日龄,每个剂量分两个试验,试验一用新城疫Ⅳ系疫苗免疫雏鸡,利用β-微量法监测血清中的血凝抑制抗体效价的动态变化;试验二用大肠杆菌油乳苗免疫雏鸡,利用间接血凝法监测血清中大肠杆菌抗体效价的动态变化。分别定期称重捕杀取脾、胸腺、法氏囊,计算免疫器官指数,取肠道内容物计数大肠杆菌和乳酸菌,测定肠道内pH值。结果表明,不同剂量的破壁蜂花粉均能不同程度地提高病毒抗原性抗体效价和菌体抗原性抗体效价,对雏鸡免疫器官的发育以及肠道内环境、菌群的平衡也有一定影响。  相似文献   
74.
AIM:To elucidate the relationship between the intracellular calcium concentration changes and left ventricular hypertrophy and function in the spontaneously hypertensive rats (SHR).METHODS:Intracellular free calcium concentrations were measured by Fura 2 methodology and left ventricular function quantitated by cardiac catheterization in 20 SHR aged 10, 22, and 34 weeks and 20 age-matched Wistar-kyoto (WKY) rats.RESULTS:(1) The systolic blood pressure(SBP), intracellular calcium concentrations and left ventricular mass / body weight index (LVM/BW) were significantly higher in all three age groups of SHR than the corresponding groups of WKY; (2) Compared with age-matched WKY groups, the peak left ventricular pressure descending rate(-dp/dtmax) decreased while left ventricular relaxation time constant (τ)increased significantly in SHR aged 22 and 34 weeks. The peak left ventricular pressure ascending rate(dp/dtmax) and the left ventricular contractility index were significantly increased only in the 34 weeks SHR; (3) Intracellular calcium concentrations showed a positive correlation with LVM/BW,SBP,-dp/dtmax and τ(r=0.47-0.83,P<0.01)and a negative correlation with dp/dtmax and the left ventricular contractility index (r=-0.46,P<0.05 and r=-0.81, P<0.01).CONCLUSION:Intracellular calcium overload is one of the potential mechanisms in the induction of left ventricular hypertrophy as well as of systolic and diastolic dysfunction.  相似文献   
75.
早熟大果鲜食枣品种‘七月鲜''   总被引:3,自引:0,他引:3  
‘七月鲜’是从合阳县农家品种中选出的早熟优良品种,比中熟品种‘梨枣’早熟20d以上;果大,整齐,平均单果质量29.8g,可溶性固形物含量28.9%,可食率97.8%,味甜,肉质细,极宜鲜食,不易裂果,早果性强,抗缩果病,节间短,树体矮小,适宜矮化密植和设施栽培。  相似文献   
76.
AIM: To investigate the protective effect of onychin on the endothelial cells injured by oxidative stress. METHODS: The injured model was established by endothelial cells treated with menadione. The growth inhibitory rate of endothelial cell was determined by MTT assay; NO2-/NO3- concentration in the medium was determined by nitrate reductase assay; eNOS and caveolin-1 protein levels were determined by Western blot. RESULTS: Onychin significantly decreased the growth inhibitory rate of endothelial cells injured by menadione, increased NO2-/NO3- concentration in the medium and eNOS activity and up-regulated caveolin-1 expression. CONCLUSION: Onychin possesses a protective effect against endothelial cell injury induced by menadione via caveolin-1/eNOS pathway.  相似文献   
77.
AIM:To manufacture recombinant protein of the highly conserved domain in human bone morphogenetic protein-1(BMP-1) using gene engineering methods as antigen for making wide spectrum antibody to BMP-1.METHODS:We analyzed the gene sequences and protein structures of BMP-1 and its related proteins, and chose a highly conserved fragment as target gene. Total RNA was prepared from human osteosarcoma cell line Saos-2, then the target gene was amplified with RT-PCR. The PCR product was cloned into prokaryotic expression vector pMAL c2 to get recombinant vector BMP-1(322-588aa)-pMAL c2. After transforming the recombinant plasmid into DH5-alpha and screening, several prositive clones were got for sequencing. Finally the transformed cells was induced with IPTG to get fusion protein.RESULTS:The BMP-1 gene fragment was successfully cloned into vector pMAL c2, and was able to express efficiently with IPTG inducement. The amount of expressed fusion protein is about 66%-72% in total volume of bacterial proteins.CONCLUSIONS:The recombinant protein contains several key domains(2 CUB domains and 1 EGF domain), which are shared by BMP-1 and its related proteins. Specific wide spectrum antibody to human BMP-1 and its related proteins may be generated with this recombinant protein antigen.  相似文献   
78.
AIM:To investigate multi-potential of rat bone marrow mesenchymal stem cells (rBMMSC) and mutation inclination, the rBMMSC were long passaged in vitro. METHODS:Cellular cycles of different passages were assayed by FACSan flow cytometry and karyotypes of passage 6, passage 25 and passage 45 were compared by G-binding analysis. RESULTS:The early passages and long-term passages all showed strong proliferation; passage 6, passage 25 and passage 45 all showed normal karyotype. CONCLUSION:Long-term culture and passage of rBMMSC still remains strong proliferation. With this capability, the mutation inclination is not enhanced.  相似文献   
79.
AIM:The effects of Yigu capsule on tartrate resistant acid phosphatase (TRAP) secretion and apoptosis in rat osteoclasts were investigated in order to further explore its mechanism of preventing and treating osteoporosis.METHODS:(1) Twenty-month-old Sprague-daweley rats were randomly divided into two groups(Yigu capsule group and saline group), and the drug-containing serum and control serum were prepared. (2) The newborn Sprague-daweley rat osteoclasts were cultured with different concentrations of Yigu capsule drug-containing serum. At different time point, TRAP activity was measured and the survival osteoclast was counted under reverse microscope.The percentage of osteoclast apoptosis was observed under fluorescence microscope after acridine orange staining.RESULTS:TRAP activity was lower and the percentage of osteoclast apoptosis was higher in drug-containing serum group than in control group at 24, 48 and 72 h(P<0.01), respectively, and the survival osteoclasts were less in drug-containing serum group than in control groups at 24, 48 and 72 h(P<0.01).CONCLUSIONS:These data suggest that Yigu capsule drug-containing serum induces apoptosis and inhibits TRAP activity in osteoclasts, which may be one of the mechanisms of Yigu capsule preventing and treating osteoporosis.  相似文献   
80.
番木瓜环斑病毒株系的分子生物学方法鉴定   总被引:6,自引:1,他引:6  
 以PRSV株系特异性引物对PRSV的PRSV126(PRSV日本分离物)、Ys、Vb和Sm等株系进行RT-PCR方法鉴定,引物PR21/PR22能把Ys从Vb和Sm中鉴定出来,PR300/PR301则能把Vb从Ys、Sm和PRSV126中鉴定出来;用限制性内切酶Hae Ⅱ、Sau3A I和Hinf I对PRSV的PRSV126、Ys、Vb和Sm等株系进行单酶切RT-PCR-RFLP分析,Hinf I能把PRSV126与Ys、Vb和Sm鉴别开来,Sau3A I能把Ys与Vb和Sm鉴别开来,Hae Ⅱ则能把Ys与PRSV126、Vb和Sm鉴别开来;以P1/P2为引物,对Vb、Ys和Sm株系进行RT-PCR-RFLP-SSCP分析,结果能一次把三者较好地区别开来。  相似文献   
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