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961.
KC Westerlind JD Fluckey SE Gordon WJ Kraemer PA Farrell RT Turner 《Canadian Metallurgical Quarterly》1998,84(2):459-464
The thermal inactivation kinetics of Salmonella enteritidis PT4 between 49 and 60 degrees C were investigated. Using procedures designed to eliminate methodological artifacts, we found that the death kinetics deviated from the accepted model of first-order inactivation. When we used high-density stationary-phase populations and sensitive enumeration, the survivor curves at 60 degrees C were reproducibly biphasic. The decimal reduction time at 60 degrees C (D60 degrees C) of the tail subpopulation was more than four times that of the majority population. This difference decreased with decreasing temperature; i.e., the survivor curves became more linear, but the proportion of tail cells remained a constant proportion of the initial population, about 1 in 10(4) to 10(5). Z plots (log D versus temperature) for the two populations showed that the D values coincided at 51 degrees C, indicating that the survivor curves should be linear at this temperature, and this was confirmed experimentally. Investigations into the nature of the tails ruled out genotypic differences between the populations and protection due to leakage from early heat casualties. Heating of cells at 59 degrees C in the presence of 5 or 100 micrograms of chloramphenicol per ml resulted in reductions in the levels of tailing. These reductions were greatest at the higher chloramphenicol concentration. Our results indicate that de novo protein synthesis of heat shock proteins is responsible for the observed tailing. Chemostat-cultured cells heated at 60 degrees C also produced biphasic survivor curves in all but one instance. Cells with higher growth rates were more heat sensitive, but tailing was comparable with batch cultures. Starved cells (no dilution input) displayed linear inactivation kinetics, suggesting that during starvation a rapid heat shock response cannot be initiated. 相似文献
962.
Both theory and research suggest that obese women may have relatively poor social relationships even if their self-reports about their relationships do not differ from the reports of nonobese women. Seventy-seven obese and 78 nonobese women completed self-report measures of social anxiety, social self-esteem, social competence, social network size, and perceived social support from friends and family. Friends and coworkers also rated these women on the same measures. The self-reports of obese and nonobese women did not differ significantly on any of these social measures, and ratings from friends and coworkers of obese women were not different from ratings of nonobese women by friends and coworkers. These results suggest that obese women may be able to overcome prejudice against obese people in their relationships with others. 相似文献
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The patterns of embryonic expression and the activities of Xenopus members of the hedgehog gene family are suggestive of role in neural induction and patterning. We report that these hedgehog polypeptides undergo autoproteolytic cleavage. Injection into embryos of mRNAs encoding Xenopus banded-hedgehog (X-bhh) or the amino-terminal domain (N) demonstrates that the direct inductive activities of X-bhh are encoded by N. In addition, both N and X-bhh pattern neural tissue by elevating expression of anterior neural genes. Unexpectedly, an internal deletion of X-bhh (delta N-C) was found to block the activity of X-bhh and N in explants and to reduce dorsoanterior structures in embryos. As elevated hedgehog activity increases the expression of anterior neural genes, and as delta N-C reduces dorsoanterior structures, these complementary data support a role for hedgehog in neural induction and anteroposterior patterning. 相似文献
966.
An unusual case of Horner's syndrome secondary to a sympathetic block in a patient with chronic adhesive arachnoiditis (CAA) is described. The patient, a 40-year-old white woman, presented with spastic paraplegia, hyperreflexia, bilateral Babinski sign, superficial and deep sensitive hypoaesthesia at the T4 level, in addition to bladder and rectal dysfunction since she was 32. At age of 38 she complained of excessive daily sweating below the T4 level, mostly at night. A 4mL 0.5% bupivacaine lumbar sympathetic block was performed. Within 15 min a right brachial paresis and an ipsilateral Horner's syndrome were noted. Speculatively, an abnormal cephalic spread of the anaesthesic due to a putative erratic space secondary to the CAA may justify the clinical picture even using a relatively small amount of anaesthesic (4 mL). 相似文献
967.
EM Hay PA Bacon C Gordon DA Isenberg P Maddison ML Snaith DP Symmons N Viner A Zoma 《Canadian Metallurgical Quarterly》1993,86(7):447-458
The British Isles Lupus Assessment Group (BILAG) index is a computerized index for measuring clinical disease activity in systemic lupus erythematosus (SLE), which was developed according to the principle of the physician's 'intention to treat'. The index allocates separate alphabetic scores to each of eight organ-based systems; a total score is not calculated. This study demonstrated good between-rater reliability for the BILAG index for each organ-based system. There was no evidence of bias between observers. The BILAG index had good overall sensitivity (87%) and specificity (99%) when compared with the 'gold standard' criterion (starting or increasing disease-modifying therapy). There were high positive predictive values overall (80%), and for each organ-based system, with the exception of the neurological system. 相似文献
968.
Paraoesophageal hiatus hernia: an important complication of laparoscopic Nissen fundoplication 总被引:2,自引:0,他引:2
DI Watson GG Jamieson PG Devitt PC Mitchell PA Game 《Canadian Metallurgical Quarterly》1995,82(4):521-523
Postoperative paraoesophageal hiatus hernia occurred in 17 of 253 patients who underwent laparoscopic fundoplication at five different hospitals. Ten patients have undergone subsequent surgical revision, eight by an open technique and two by laparoscopy. This complication may have important implications for the technique of laparoscopic fundoplication, as it is possible that routine posterior repair of the diaphragmatic hiatus may greatly reduce the risk. Early postoperative contrast radiology may also achieve earlier diagnosis, enabling correction to be undertaken by laparoscopy. 相似文献
969.
970.