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81.
Two wettable powders (Bactimos and Vectobac) and one flowable concentrate (Teknar) of Bacillus thuringiensis var. israelensis (B.t.i.) and primary powders of Bacillus sphaericus isolates 1593 and 2362 were evaluated (laboratory) against field-collected larvae of Anopheles gambiae s.l. and Culex quinquefasciatus in Ouagadougou, Burkina Faso. Bactimos, Vectobac and a Corn-cob B.t.i. formulation (ABG-6138G) were field tested against Cx. quinquefasciatus and An. gambiae s.l. The isolates of B. sphaericus were also tested against An. gambiae s.l. in artificial ponds. Both wettable powders of B.t.i. showed superior activity than the flowable concentrate formulation against An. gambiae s.l. in the laboratory. Culex quinquefasciatus was more susceptible (3-4X) to B.t.i. (Bactimos) than An. gambiae s.l. The isolates of B. sphaericus were more effective (2-3X) against both mosquito species than Bactimos. In a ditch and two channels, Bactimos, Vectobac and ABG-6138G at 0.65, 1.5 and 5.6 kg/ha, respectively, gave 91-100% control of Cx. quinquefasciatus within 3 days of treatment. The same formulations at rates ranging from 0.25 to 5.6 kg/ha, produced 82-97% control of An. gambiae s.l. in rainwater pools 24 h after treatment. Isolates 1593 and 2362 at 0.12 and 0.24 kg/ha gave excellent control of An. gambiae s.l. in artificial ponds.  相似文献   
82.
Summary A recombinant vaccinia virus designated VgBt which expresses a truncated secreted herpes simplex virus gB (gBt) was constructed and compared to V11gB, a vaccinia recombinant previously studied which expresses gB exclusively on the surface of infected cells. Indirect immunofluorescence assay (IFA) revealed that gBt was strongly associated with the surface of infected cells despite being released slowly into the cell culture medium. Both gB and gBt existed as oligomers, and both membrane bound and secreted forms of gBt exhibited heparin-binding activity. In protection studies VgBt and V11gB conferred equivalent protection against both homologous (HSV-1) and heterologous (HSV-2) challenge with HSV.  相似文献   
83.
An Alternative Surgical Technique in Orthotopic Cardiac Transplantation   总被引:8,自引:0,他引:8  
A bstract Forty patients underwent orthotopic cardiac transplantation at Wythenshawe Hospital between May 1991 and November 1992. Twenty patients had transplantation using an alternative technique that preserves the shape of the left atrium and leaves the right atrium intact (group A). The remaining twenty had conventional transplantation using the technique described by Lower and Shumway (group B). The patients were randomized to either the new or the conventional technique on an alternate basis. There was no mortality in group A, but two patients in group B developed right ventricular failure and died. Two patients in each group developed nodal rhythm and all four recovered sinus rhythm. Echocardiography and Doppler velocimetry at the transvalvular level confirmed normal atrial function in group A with erratic atrial contraction wave in group B. There was also slightly lower incidence of mitral and tricuspid valve regurgitation in group A than in group B. The improved atrial function in group A may play a part in the prevention of right sided failure following cardiac transplantation.  相似文献   
84.
A new dimeric indoline alkaloid has been isolated from the leaves of PETCHIA CEYLANICA. Its structure has been assigned as 1 on the basis of spectral studies. Its stereochemistry has been established by NOE difference measurements.  相似文献   
85.
Chronic exposure to cannabis extract or delta-9-tetrahydrocannabinol (THC) has been reported to produce hippocampal neuropathology in rats, as well as classical "hippocampal" behavioral deficits. In an attempt to replicate and extend these findings, male rats were exposed to THC for 13 consecutive weeks, beginning in early adolescence. Drugs were administered five consecutive days a week (Monday through Friday). There were five dose levels: vehicle control, 5, 10, or 20 mg/kg, p.o., and 20 mg/kg THC four days a week (Monday-Thursday), followed by 60 mg/kg on Friday. Following THC exposure, all animals were withdrawn from drugs for seven weeks prior to behavioral testing. Three behavioral tasks previously shown to be sensitive to hippocampal damage were assessed. These were habituation of open-field activity, 24-hr passive avoidance response retention, and complex maze performance. A fourth task, emergence latency, was also included because it has been determined to be sensitive to "anxiety" levels. To facilitate interpretation of the complex maze data, two additional experiments are also reported. One experiment tested rats exposed to trimethyltin (TMT, a potent hippocampal neurotoxicant) on the complex maze. The second assessed the affects of chronic/acute benzodiazepine (BZ) exposure upon maze performance. Test results did not suggest that chronic THC exposure produced behavioral deficits resembling those seen following hippocampal damage. Habituation rates in an activity monitor were identical for all exposure groups, and there was no passive avoidance retention deficit. Further, while TMT caused pronounced abnormalities in the complex maze, chronic THC exposure at the two highest dose levels significantly improved maze performance, similar to BZ effects on this task. Chronic THC also appeared to reduce freezing on the emergence task, another anxiolytic-like effect. These results support other reports of persistent long-term behavioral effects of chronic THC exposure. However, they suggest that some behavioral effects may more closely resemble the effects of minor tranquilizers rather than hippocampal damage.  相似文献   
86.
Health and nutrition education involves not only conveying new information and concepts, but also persuading the target population to engage in innovative action and direct participation. This process can be thwarted if cultural factors are ignored, particularly in dealing with a tribal population. In a country like India, communication with tribals is influenced by ethnic and cultural diversities, different types of ecological settings, a low literacy level, geographic isolation, the lack of development infrastructure, language barriers, health taboos and problems, a lack of access to modern media forms, and food availability and use. Most suitable for working with tribal populations appear to be the media of the spoken work, song and drama, games, exhibitions at the weekly market and yearly festivals, and pictorial aids. Since communication is a 2-way process, there must be a shared frame of reference among scientists, communicators, and receivers. Moreover, even when health education messages are delivered through culture-specific entertainment programs, they must be part of a comprehensive health and development package in which extension workers are backed up by health professionals and integrated programs.  相似文献   
87.
The volume of the nuclei and nucleoli of certain hypothalamic centers (SON, PVN, SCN, AN, VMN) was determined in control rats and in rats after deafferentation of the mediobasal hypothalamus. Sex differences were found in the parvocellular formations of the control animals: The volumes of nuclei and nucleoli of neurons of AN and VMN, and also of the nucleolus of SCN neurons were larger in females than in males. After deafferentation of the mediobasal hypothalamus the volume of the cell nuclei was increased, especially in hypothalamic formations located outside the isolated zone. This increase was more clearly defined in rats constantly in a state of estrus after the operation. Statistically significant differences between volumes of both nuclei and nucleoli of the cells in subgroups of rats with permanent estrus and with permanent diestrus were found only in the case of SCN. No such differences were found for AN, despite the considerable difference in the constant of luteinizing hormone in the pituitary of the same rats. It is suggested that gonadotropin releasing factors are not produced by the cells of AN and that control over the succession of phases of the sex cycle may be exerted by SCN.Laboratory of Neuroendocrinology, I. M. Sechenov Institute of Evolutionary Physiology and Biochemistry, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 352–354, March, 1980.  相似文献   
88.
OBJECTIVE: The purpose of this study was to investigate the presence of emotional abuse and two psychosocial constructs (self-blame and self-silencing) in a sample of women diagnosed with irritable bowel syndrome (IBS) relative to a comparison sample of women diagnosed with inflammatory bowel disease (IBD). METHODS: Women diagnosed with IBS (N = 25) were compared with women diagnosed with IBD (N = 25) on measures of history of abuse, self-blame, and self-silencing. RESULTS: It was found that women in the IBS sample scored significantly higher on emotional abuse, self-blame, and self-silencing than did women in the IBD sample. These three variables were also found to be significantly intercorrelated in both the IBS and IBD samples. Finally, emotional abuse was significantly higher in IBS patients than in IBD patients beyond the differences accounted for by physical and/or sexual abuse history. CONCLUSIONS: These findings empirically demonstrate an association between IBS and emotional abuse, as well as a possible connection with psychosocial variables, that may mediate the connection between emotional abuse and functional bowel symptoms. We suggest that these variables be further evaluated in the context of clinically relevant research on IBS.  相似文献   
89.
To determine the effect of prostaglandin-synthesis inhibition on ureteral motility, isolated rings of sheep ureters were suspended for recording isometric tension in organ baths filled with Krebs-Henseleit solution. The non-steroidal anti-inflammatory drugs (NSAIDs) indomethacin and diclofenac sodium (10(-5) M) inhibited rhythmic ureteral motility by reducing frequency, amplitude and finally stopping contractions. Prostaglandin F2 alpha, 6-keto-prostaglandin F1 alpha and thromboxane B2 were determined by radioimmunoassay in the bathing solution before and after addition of NSAIDs. Peak contractile activity at 100 min of suspension was associated with increased concentration of all three prostanoids and 50 min after addition of indomethacin and diclofenac sodium when rhythmic contractions stopped, concentration dropped to low levels. The concentration of prostaglandins released into the organ bath were not quantitatively related to the frequency of contractions and therefore do not seem to affect pacemaker activity within ureteral smooth muscle but rather intercellular recruitment of myo-genically active fibres. These findings indicate that prostaglandins play a role in the motor control of the ureter, and that non-steroidal anti-inflammatory drugs exert an inhibitory action.  相似文献   
90.
Chronic Allograft Rejection   总被引:3,自引:0,他引:3  
  相似文献   
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