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991.
992.
Eighteen esters of resolved cis- and trans-3-(2,2-difluoro, -dichloro or -dibromovinyl)-2,2-dimethylcyclopropanecarboxylic acids with 5-benzyl-3-furylmethyl, 3-phenoxybenzyl and α-cyano-3-phenoxybenzyl alcohols were prepared and evaluated for insecticidal activity against Musca domestica L. and Phaedon cochleariae Fab. Chlorine and bromine substituted esters are more active, in general, than those with fluorine, and in the most active esters, the cis isomer is more effective than the trans.  相似文献   
993.
994.
Purified and semipurified diets yielding good growth and survival of lobsters (Homarus americanus) have been developed. Growth of animals fed the semipurified diet for 18 months at 20±1°C indicates that market size (.5 kg) could be attained within 2.5 years. The semipurified diet contains 53% (dry weight) protein using casein, shrimp meal, gluten, and egg white as different protein sources. Substitution of these particular sources of protein with soy protein, shrimp protein, a soy protein-shrimp meal combination, or bacterial cell protein caused significant reductions in growth. Similar growth can be achieved when the protein level of the semipurified diet is reduced to 30.5%. It appears that if specific protein and energy requirements are met, diets containing low protein levels can be nutritionally adequate for optimal growth, thereby increasing the possibility of cost-effective diets for intensive lobster culture.  相似文献   
995.
996.
Four resistance factors were isolated genetically from the NPR strain of houseflies (Musca domestica L.), which resists natural pyrethrins, and were characterised toxicologically. The four factors were : pen, which reduces the rate of penetration of insecticides through the cuticle; kdr-NPR, a general pyrethroid resistance mechanism unaffected by the synergist sesamex; py-ses, a mechanism of resistance to natural pyrethrins that can be suppressed by sesamex; and py-ex, a factor that gives strong resistance to synergised natural pyrethrins and to the new synthetic esters, e.g. resmethrin, but little or none to natural pyrethrins alone.  相似文献   
997.
998.
999.
Ectopic cilium was diagnosed by slit-lamp biomicroscopy and treated surgically by transconjunctival excision in seven adult horses. All cases presented with a common history of blepharospasm, ocular discharge and keratitis. Ophthalmic examination revealed a single translucent cilium in the upper eyelid palpebral conjunctiva, emerging approximately 5 mm from the eyelid margin. Corneal ulceration was not observed in any horse. Most horses responded well to transconjunctival surgical excision. There was recurrence of ectopic cilium 6 weeks postoperatively in one horse. Histopathologic examination was performed in two cases and confirmed the diagnosis of ectopic cilium in one horse. This is the first publication of ectopic cilia in horses and emphasizes their importance as etiology for epiphora, blepharospasm and keratitis.  相似文献   
1000.
Objective To investigate the effect of 0.02% tacrolimus in aqueous suspension on tear production in dogs with keratoconjunctivitis sicca (KCS). Animals studied One hundred five dogs diagnosed with KCS [Schirmer tear test (STT) ≤ 10 mm/min and clinical signs of dry eye]. Eyes with marginally decreased STT (11 ≤ 15 mm/min) and clinical signs of dry eye were also evaluated. Procedure The investigation was conducted in two parts: an initial efficacy study and a subsequent double blinded controlled study. In the efficacy study, the effect of topical tacrolimus (formerly FK‐506) on tear production in dogs with primary KCS was evaluated. Dogs were divided into four categories: 1) 59 eyes (38 dogs) naïve to tear stimulation therapy with initial STT ≤ 10 mm/min; 2) 28 eyes (21 dogs) naïve to tear stimulation therapy with initial STT 11 ≤ 15 mm/min; 3) 30 eyes (15 dogs) maintained successfully on CsA therapy; 4) 47 eyes (24 dogs) unresponsive to CsA therapy. STT and clinical signs were evaluated prior to and after 6 to 8 weeks of twice daily tacrolimus administration. Tacrolimus was substituted for CsA therapy in categories 3 and 4. The controlled study compared the effect of topical tacrolimus in aqueous suspension to administration of the aqueous carrier alone on tear production in 20 dogs with primary KCS. Results In the efficacy study, STT increased by 5 mm/min in 84.7%, 25.0%, 26.7% and 51.1% of eyes in categories 1, 2, 3 and 4 respectively after tacrolimus administration. Eighty‐three percent of eyes with extremely low initial STT (≤ 2 mm/min), increased 5 mm/min after tacrolimus. In the controlled study, STT increased by 5 mm/min in 7/10 dogs (14/20 eyes) that received tacrolimus and in none of the 10 dogs that received aqueous carrier alone. Dogs receiving just the aqueous carrier were subsequently treated with tacrolimus, and STT increased 5 mm/min in 9 dogs (18/20 eyes) after administration. Conclusions Twice daily administration of 0.02% tacrolimus in aqueous suspension effectively increased tear production in dogs with KCS. Topical tacrolimus is a promising alternative to topical CsA for treatment of KCS and may be beneficial in patients with less than optimal response to topical CsA.  相似文献   
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