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81.
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83.
Prof. Dr. Max Dingler 《European Journal of Forest Research》1934,56(10):350-351
84.
Phloem mobility is a desirable attribute for pesticides in many applications, and the physicochemical properties necessary for phloem mobility are now well understood. However, attempts to derivatize pesticides to make them phloem mobile are often frustrated by a concomitant loss of activity. This study describes a phloem-mobile pro-nematicide, a hydroxymethyloxamyl glucuronide (JR522) coupled with an in-situ activation mechanism in transgenic tobacco expressing Escherichia coli β-glucuronidase in its root tips. When applied foliarly to the transgenic tobacco, JR522 and its methyl ester (JM775) showed greater nematicidal activity than oxamyl against root-knot nematodes. This example of combining pro-pesticide chemistry with crop genetic engineering for site-specific activation provides a model system for demonstrating how to circumvent the often mutual exclusivity of phloem mobility and pesticidal activity. Additional advantages of this scheme include the potential mammalian safety of the propesticide, as exhibited by JR522 in this study, and a high degree of site-specific release of xenobiotics in plants. 相似文献
85.
OBJECTIVE: To evaluate the mechanical properties of the 18 and 36 kg Securos Cranial Cruciate Ligament Repair System. STUDY DESIGN: In vitro mechanical evaluation. SAMPLE POPULATION: Loop constructs of 18, 27, and 36 kilogram test (kgt) nylon leader line (NLL) secured with Securos crimp-clamps (SCC, n=40 per NLL test weight) or by a clamped square knot (CSK; n=40/NLL test weight). METHODS: The 36 kg SCC were used for the 27 and 36 kgt NLL, and 18 kg SCC were used for the 18 kgt NLL. Loop constructs were mounted on a material testing machine, and distracted at 500 mm/min for static tests, and for cyclic tests at 500 mm/min to a distraction limit of 6 mm (18 kgt) or 7.5 mm (27 and 36 kgt) for 49 cycles, until failure. Constructs were tested at 20 degrees C except for 1 group of 27 kgt CSK loops tested at 40 degrees C. Load at failure, elongation, and stiffness was recorded and compared between groups under static or cyclic testing conditions. RESULTS: All 27 and 36 kgt loops failed by disruption of NLL contained within the knot or crimp-clamp, whereas 18 kgt SCC loops failed by the NLL pulling through the crimp-clamp. The 18 kg SCC loops had considerable variability in ultimate load and elongation (coefficient of variation 29.6% and 18.3%, respectively). There was no significant difference in elongation between 27.3 kgt CSK loops tested at 20 degrees C and 40 degrees C. Generally, in both static and cyclic testing, SCC constructs formed with 27.3 or 36.4 kgt NLL performed as well or better than CSK constructs, resulting in loops that were strong, underwent minimal elongation, and had high stiffness. CONCLUSION: The results support use of the 36 kg Securos system but not the 18 kg Securos system (with the clamp and crimping device used). The significantly lower load required for failure, slippage through the clamp, and substantial variability suggested that the crimp tube diameter or the crimping device tested may be inappropriate for use with 18 kgt NLL. CLINICAL RELEVANCE: Surgeons should be aware that crimp-clamp design is important in controlling suture slippage or breakage within the clamp, and that novel systems should undergo mechanical testing with the size suture material they are intended to secure before clinical use. 相似文献
86.
Objective-To determine whether partial transection of the medial branch of the suspensory ligament (MBSL) alters equine third metacarpal bone (MC3) condylar surface strains and forelimb, distal joint angles in a manner consistent with promotion of lateral condylar fracture. Study Design-In vitro biomechanical experiment. Sample Population-Right forelimbs from 7 Thoroughbred horse cadavers. Methods-Lateral and medial MC3 condylar, dorsal and abaxial, bone surface strains and distal joint angles were measured both before and after partial transection of the MBSL during in vitro axial limb compression. Dorsal, principal bone strains and abaxial, uniaxial, and proximodistal strains were compared before and after MBSL partial transection at 1,400-, 3,000-, and 5,600-N loads. Results-Bone strains increased in all locations with increasing axial load. All lateral condylar bone strains were significantly higher, and abaxial surface medial condylar bone strain was significantly lower, after partial transection of the MBSL. Respective distal joints became more flexed or extended as axial load increased but were not significantly different after partial transection of the MBSL. Conclusions-Partial transection of the MBSL increases in vitro MC3 lateral condylar bone surface strains. Clinical Relevance-Loss of integrity of the medial branch of the suspensory ligament could increase the risk for lateral condylar fracture in Thoroughbred horses by amplifying bone strain in the lateral condyle. 相似文献
87.
Paul MA Appel M Barrett R Carmichael LE Childers H Cotter S Davidson A Ford R Keil D Lappin M Schultz RD Thacker E Trumpeter JL Welborn L;American Animal Hospital Association Canine Vaccine Task Force 《Journal of the American Animal Hospital Association》2003,39(2):119-131
The AAHA has undertaken the development of this document in an effort to inform veterinary practitioners, clarify misunderstandings held by veterinarians, and encourage practitioners to recognize that immunization of patients is a medical procedure. As such, it is bound by the same tenets that govern the recommendation of other medical procedures-principally, that it be tailored to the needs of the individual patient. Many diseases we immunize against are ubiquitous. Many are serious and some even life threatening. Some are of limited demographic concern given the exposure risk for each patient. These factors have all been considered in developing the AAHA Canine Vaccination Guidelines. In the end, each veterinarian must do what he or she determines to be in the best interest of the patient. Vaccination of individual animals produces not only individual immunity but also population or herd immunity. Since we have no readily available and reliable way to determine if each patient has developed an adequate immune response, we encourage the practice philosophy of vaccinating more patients while vaccinating each patient no more than needed. 相似文献
88.
89.
Recombinant bovine soluble CD14 reduces severity of experimental Escherichia coli mastitis in mice 总被引:3,自引:0,他引:3
Endotoxin, or lipopolysaccharide (LPS), is responsible for pathogenesis of infections induced by Gram-negative bacteria, such as E. coli. The cellular response to LPS is modulated by interactions among LPS, LPS-binding protein (LBP) and CD14. Accumulated evidence shows that the soluble form of CD14 (sCD14) competes with membrane-bound CD14 (mCD14) for LPS and plays a pivotal role in regulating bacterial infection and septic shock caused by Gram-negative bacteria. Recombinant bovine sCD14 (rbosCD14) was produced by transfected insect sf/9 cells and its biological function was evaluated in mice. Eighty-one 8-week old BALB/cj female mice were randomly assigned to two groups, and injected intraperitoneally with either LPS (8 microg/g of body weight, n = 41) or LPS plus rbosCD14 (6.8 microg/g of body weight, n = 40). Survival rate at 24 h after injection for mice injected with either LPS or LPS plus rbosCD14 was 30 and 72%, respectively (P < 0.01). At 48 h survival rate was 7 and 37%, respectively (P < 0.01). To investigate the protective effect of rbosCD14 on experimentally induced mastitis in mice, two abdominal contralateral mammary glands of 7 lactating BALB/cj mice were injected through the teat canal with 10-20 colony-forming units (CFU) of Escherichia coli. One gland simultaneously received rbosCD14 (6 microg) and the other saline. At 24 h after challenge, glands that received rbosCD14 had less swelling and hemorrhaging, significantly lower bacterial counts (P < 0.05) and lower concentrations of TNF-alpha (P < 0.05). Results indicate that rbosCD14 is biologically functional and reduces mortality in mice from endotoxin shock and severity of intramammary infection by E. coli. 相似文献
90.
Max Dingler 《Journal of pest science》1933,9(1):1-9
Ohne Zusammenfassung
Mit 8 Abbildungen. 相似文献