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991.
Speakers at the 1996 Midlands Region Symposium (Go green - like it or lump it) ranged from dyemakers to retailers; Rebecca Reid reports on their predictions for the industry.  相似文献   
992.
Stereo perception and dead reckoning for a prototype lunar rover   总被引:5,自引:2,他引:3  
This paper describes practical, effective approaches to stereo perception and dead reckoning, and presents results from systems implemented for a prototype lunar rover operating in natural, outdoor environments.The stereo perception hardware includes a binocular head mounted on a motion-averaging mast. This head provides images to a normalized correlation matcher, that intelligently selects what part of the image to process (saving time), and subsamples the images (again saving time) without subsampling disparities (which would reduce accuracy). The implementation has operated successfully during long-duration field exercises, processing streams of thousands of images.The dead reckoning approach employs encoders, inclinometers, a compass, and a turn-rate sensor to maintain the position and orientation of the rover as it traverses. The approach integrates classical odometry with inertial guidance. The implementation succeeds in the face of significant sensor noise by virtue of sensor modelling, plus extensive filtering.The stereo and dead reckoning components are used by an obstacle avoidance planner that projects a finite number of arcs through the terrain map, and evaluates the traversability of each arc to choose a travel direction that is safe and effective. With these components integrated into a complete navigation system, a prototype rover has traversed over 1 km in lunar-like environments.  相似文献   
993.
To study the immunotherapeutic potential of interleukin-4 (IL-4) delivered in vivo via a recombinant vaccinia virus, a thymidine kinase-negative (TK-) vaccinia virus that expressed the murine IL-4 gene (VV1/IL-4) was constructed. When mice were inoculated with 10(7) plaque-forming units (pfu) of VV1/IL-4 subcutaneously (s.c.), 10(5) pfu/cm2 were found in skin, and smaller numbers in liver and kidney between 1 and 7 days after infection; few viral pfu were found in spleen and lung, or in any organ after intravenous infection. This suggested that recombinant vaccinia viruses might be most efficient at delivery of cytokine genes to the skin. Because IL-4 has recently been found to have potent anti-tumor activity, the effect of recombinant virus infection on the development of s.c. tumors was studied. A single s.c. inoculation with VV1/IL-4 delayed the development of NCTC 2472 tumors, but when VV1/IL-4 was inoculated s.c. weekly for 8 weeks, tumor development was completely prevented in 93% of mice. Similarly, the development of M-3 melanoma tumors was also prevented by weekly s.c. inoculations of VV1/IL-4. About 40% of mice treated with control VV2/beta gal by the same regimen also failed to develop tumors. Weekly virus treatment did not prevent NCTC 2472 tumor development in athymic nu/nu mice, suggesting that mature T cells are required for expression of VV1/IL-4 induced antitumor activity. Thus, recombinant vaccinia viruses may be especially well suited for convenient therapeutic delivery of immunomodulator genes to skin-related sites.  相似文献   
994.
BACKGROUND: A randomized trial was conducted to evaluate the impact of a community-based intervention on mammography use among low-income women living in public housing. METHODS: All 41 public housing high-rise buildings were randomized to treatment and delayed treatment (control) conditions. After a cross-sectional baseline survey, an intervention called Friend to Friend was conducted in the treatment buildings by American Cancer Society and building resident volunteers. The intervention consisted of a health professional talk, small group discussions, and an opportunity to request assistance in obtaining a mammogram or mammogram reminder. A second cross-sectional survey was conducted to measure differences in screening rates between the study groups. RESULTS: Participation in the intervention averaged 27%. The study groups were equivalent at baseline. At follow-up, the proportion of women age 50-79 years who reported mammography screening in the previous 15 months was significantly higher in the treatment group (64%) than in the control group (52%). Breast cancer knowledge, attitudes, and beliefs did not differ between groups. CONCLUSIONS: These findings suggest that a multidimensional intervention which reaches women within their social environment and uses community volunteers can increase mammography utilization among women in public housing.  相似文献   
995.
We have described a rare case of multifocal granular cell myoblastoma affecting respiratory and hepatobiliary tracts in a young woman. The patient had successful tracheal resection and biliary stent placement to alleviate symptoms. Long-term follow-up will clarify the true nature of the disease.  相似文献   
996.
To determine factors influencing Hispanic women's HIV-related communication and condom use with their primary male partner, 189 Dominican, Puerto Rican, and Mexican women were interviewed regarding sexual behaviour and condom use, relationship characteristics, perceived risk for HIV, and HIV-related communication with the primary male partner. Level of HIV-related communication with the primary male partner was associated with the woman's perceived risk for HIV and her rating of the openness with which she could communicate with her primary partner. Mexican women were less likely than Puerto Rican or Dominican women and women with multiple partners were less likely than those with one partner to communicate about HIV-related issues with their primary partner. Women reporting more condom use with their primary partner were younger, had discussed HIV-related issues more with the primary partner, and were less likely to expect negative reactions to requests for condom use than those reporting less condom use. These results suggest that prevention programmes that increase both general and HIV-specific communication between members of a couple may facilitate safer sex practices by the couple. Prevention programmes that encourage women to insist on condom use should consider the woman's expectations about her partner's reaction as a potential barrier to the initiation of safer sex practices.  相似文献   
997.
On the basis of reactions described in the synthetic literature, a two-step chiral derivatization sequence was developed for the anticancer agent cyclophosphamide (CP). The sequence involves amidoalkylation of CP with anhydrous chloral containing 1% dimethylformamide followed by acylation of the resulting secondary alcohol with a chiral carboxylic acid chloride, (+)-6-methoxy-alpha-methyl-2-naphthaleneacetyl chloride, to form a diastereomeric pair. Derivatized (-)-CP and (+)-CP exhibited retention times of 17.2 and 20.7 min, respectively, when chromatographed on Hypersil ODS with acetonitrile/phosphate buffer (pH 6.8) as the mobile phase. Preparation of the individual diastereomers from enantiomerically pure CP enabled correlation of the chromatographically observed peaks with a particular enantiomer. Various aspects of the overall assay methodology have been systematically investigated (derivatization solvents, temperatures, reaction time, and work-up procedure) and optimized on the scale required for trace analysis in biological fluids. Calibration curves were established for each enantiomer in spiked human plasma over the therapeutically relevant concentration range of 0.99-49.94 micrograms/mL.  相似文献   
998.
Fourteen consecutive patients with hepatocellular carcinoma (HCC) and diaphragmatic invasion found during operation and confirmed histopathologically were studied. They were treated by resection of the liver tumour en bloc with part of the diaphragm. Eight of the 14 patients had a diaphragmatic hump on chest radiography. Preoperative ultrasonography, computed tomography and hepatic angiography were unable to diagnose diaphragmatic invasion in these patients. A control group of 14 closely matched patients were selected from 98 undergoing curative resection for HCC during the period of the study. No evidence of a diaphragmatic hump was found in the control patients (P < 0.001). There was no significant difference in survival, operative morbidity or mortality rates between the two groups. In patients with HCC situated in the dome of the liver, the presence of a diaphragmatic hump on chest radiography strongly suggests invasion of the diaphragm. There was no difference in outcome in patients with or without diaphragmatic invasion; the tumour should be resected if the patient is fit for operation.  相似文献   
999.
To determine lead exposure among children in Bahrain, a total of 280 shed deciduous whole teeth were collected from 269 children. Teeth were analyzed for lead concentrations using atomic absorption spectrophotometry with electrothermal atomization. Children were between 5 and 15 years old. The study period extended from July 1993 to April 1994. The study showed that the overall mean tooth-lead level was 4.3 micrograms/g dry weight with a range of 0.1-60.8 micrograms/g dry weight. The cumulative frequency distribution revealed that 35% of the teeth had a lead concentration of more than 4 micrograms/g dry weight. The tooth-lead concentrations differed according to the tooth type age. The child's sex, nationality, area of residence and socio-economic status had no impact on tooth-lead level. In conclusion, lead is present in toxic concentrations in 35% of the teeth of the children studied. Urgent measures are needed to eliminate lead from gasoline, paint and other sources in the environment.  相似文献   
1000.
An FP prostanoid receptor isoform, which appears to arise from alternative mRNA splicing, has been cloned from a mid-cycle ovine large cell corpus luteum library. The isoform, named the FP(B) receptor, is identical to the original isoform, the FP(A), throughout the seven transmembrane domains, but diverges nine amino acids into the carboxyl terminus. In contrast to FP(A), whose carboxyl terminus continues for another 46 amino acids beyond the nine shared residues, the FP(B) terminates after only one amino acid. The FP(A) isoform appears to arise by the failure to utilize a potential splice site, while a 3.2-kilobase pair intron is spliced out from the FP gene to generate the FP(B) isoform mRNA. The two isoforms have indistinguishable radioligand binding properties, but seem to differ in functional coupling to phosphatidylinositol hydrolysis. Thus, in COS-7 cells transiently transfected with either the FP(A) or the FP(B) receptor cDNAs, prostaglandin F(2alpha) stimulates inositol phosphate accumulation to the same absolute maximum, but the basal level of inositol phosphate accumulation is approximately 1.3-fold higher in cells transfected with the FP(B) as compared with cells transfected with the FP(A) isoform. Using the polymerase chain reaction, mRNA encoding the FP(B) isoform was identified in the ovine corpus luteum.  相似文献   
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