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491.
We studied the microbial changes on fresh (still warm) pork carcasses immediately after electrostatic spraying of lactic acid solutions and during chilled storage. Lactic acid decontamination (LAD) included electrostatic spraying of hot (55C) solutions of 1% lactic acid for 90 s and 2%- and 5% lactic acid for 30 and 90 s. The treatments increased the carcass surface temperature from 22C to about 32–43C. The bactericidal activity of lactic acid killed mainly Gram-negative bacteria. Reductions in "total" psychrotrophic Gram-negative and Entero-bacteriaceae counts were found reliable indicators for the efficacy of LAD. Hot 2–5% LAD treatments achieved overall reductions in Gram-negative psychrotrophs ranging from 0.8 to more than 1.4 log10 cfu per cm2 . Overall reductions in mesophilic Enterobacteriaceae counts ranged from approximately 1.2 to more than 1.8 log10 cfu per cm2 . Treatments with 1% lactic acid achieved marginal 0.5–0.6 overall log10 reductions in these groups of organisms. Bactericidal effects after LAD occurred during a lag period of whose duration increased with the lactic acid concentration of the spray solution. The lag lasted less than 1 day on 1% LAD, 2 days on 2% LAD and 4 days on 5% LAD meat. During these lags the meat surface pH rose from pH 2.7 to 3.2 immediately after LAD to pH 4.8 to 5.2. During aerobic chilled storage after LAD the growth of Gram-negative psychrotrophs was controlled only temporarily. These organisms became the dominant group of organisms. The practical utility of electrostatic spraying of fresh pork carcasses with hot 1–5% LAD to improve the keeping quality is questionable . 相似文献
492.
OM Grindel'' IuM Koptelov EL Masherov IN Pronin 《Canadian Metallurgical Quarterly》1998,48(4):671-686
This article discusses the following aspects of the management of the N+ neck: evolution of neck dissection; specificity of staging of the clinically N+ neck; limitations of neck dissection in patients with adverse histologic features; management of bilateral nodal metastases, fixed nodes, and nodes with involvement of skin, nerves or the carotid artery; retropharyngeal nodes; and salvage treatment of the N+ neck following prior irradiation. A summary of the author's own approach is then presented. 相似文献
493.
The cytopathogenic action of P. mallei on macrophages of golden hamsters and transplantable Hep-2 cell culture was studied. It was shown that the culture test systems may be efficient in estimation of the P. mallei virulent properties. The effect of antibacterial drugs on intracellular P. mallei was also studied. 相似文献
494.
IN Krasikova SV Khotimchenko TF Solov''eva YS Ovodov 《Canadian Metallurgical Quarterly》1995,1257(2):118-124
Glioblastoma multiforme (GBM) is the most malignant glial brain tumor in humans. The fact that deleted copies of chromosome 10 are observed frequently in primary GBM tumors supports the hypothesis that one or more tumor suppressor genes located on chromosome 10 occupy crucial growth control checkpoints for glial cells. Deletion mapping in primary GBM tumors using the loss of heterozygosity (LOH) test has implicated the 10q24-10qter region as one possible site for a gene. We report here on the molecular cytogenetic analysis of chromosome 10 abnormalities in a human GBM cell line, JBSA. LOH testing showed that JBSA cells were hemizygous for chromosome 10. Molecular cytogenetic analysis showed that the undeleted homologue was involved in a reciprocal translocation t(7;10)(p21;q22). The translocation breakpoint on chromosome 10 lay within band q22 between D10S19 and D10S4. The fact that JBSA cells lack one homologue of chromosome 10 and carry a translocation breakpoint on the remaining one, proximal to the smallest region of overlap reported in primary tumor deletions, suggests that 10q22 may be another possible site for a tumor suppressor gene involved in GBM. 相似文献
495.
496.
G Brandst?tter IN Marks F Lanza D Kogut B Cobert JP Savitsky W Bender R Labs H Wurzer 《Canadian Metallurgical Quarterly》1995,17(3):467-478
Roxatidine (150 mg, 312 patients) was compared with ranitidine (300 mg, 308 patients) in a randomized, double-blind, parallel-group, 6-week therapeutic study for the treatment of patients with uncomplicated, benign gastric ulcer disease. The study end points (verified by using endoscopy results) were fully healed ulcers at 4 or 6 weeks. The results of roxatidine therapy were comparable to those of ranitidine therapy: healing rates of 52% and 54% at week 4 and 77% and 76% at week 6 were recorded for roxatidine and ranitidine, respectively. The drugs produced comparable reductions in ulcer diameters and decreases in abdominal pain. Adverse events associated with both roxatidine (27%) and ranitidine (28%) were headache, diarrhea, and dizziness; rash was associated in 6 of 8 cases and in only 1 case with roxatidine. In this trial, roxatidine 150 mg once daily was as efficacious and safe as ranitidine 300 mg once daily for treatment of patients with uncomplicated, benign gastric ulcer disease. 相似文献
497.
498.
The development of allergy in germ-free rats in chronic vibriocarriership was studied. The formation of specific delayed type hypersensitivity was found to occur to a limited extent in the animals devoid of normal microflora. The picture of hyperergic inflammation was revealed in the lymph nodes of vibriocarrier rats, the test for specific allergen being positive. 相似文献
499.
The methyl cellulose modification of the CFUe technique has been applied to 14 day fetal liver and adult bone marrow and spleen from CBA/CA mice. Optimized doses of fetal calf serum, alpha-thioglycerol, erythropoietin and cell suspensions have been obtained from dose response curves in order to standardize the technique. The slopes of the erythropoietin and cell dose response curves indicate a greater sensitivity by fetal liver to the hormone than bone marrow or spleen. The proportion of cells in the DNA synthesis phase of the cell cycle, as measured by the CFUe technique, has been estimated by administering hydroxyurea. Two hours after the drug was injected, 89% of fetal liver cells, 71% of bone marrow cells and 81% of spleen cells were found to be in the S-phase. 相似文献
500.
V.A. Getman A.I. Germanov A.Ya. Derkach I.M. Karnaukhov A.A. Lukhanin A.A. Razumnyj E.A. Sporov 《低温学》1980,20(2):98-100
The paper deals with the design and studies of the He3 continuous flow cryostat of high cooling power operating at 0.5 K intended for polarized targets. A special device for changing the target material damaged under irradiation without heating up the cryostat is described. 相似文献