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991.
992.
SA Ewing JE Dawson RJ Panciera JS Mathew KW Pratt P Katavolos SR Telford 《Canadian Metallurgical Quarterly》1997,34(6):710-718
In contrast to the anticipation that in sepsis granulocyte colony-stimulating factor (G-CSF) would overactivate the nonspecific immune system by recruiting and priming leukocytes with consequent aggravation of inflammatory tissue lesions, recombinant (r) G-CSF pretreatment was protective in various experimental non-neutropenic models of inflammation. The mechanisms of protection, however, are not fully understood. Using intravital fluorescence microscopy, we show that rG-CSF enhances leukocyte endothelial cell interaction within the microvasculature of normal rat livers, whereas rG-CSF pretreatment of animals exposed to lipopolysaccharide (LPS) attenuates the LPS-induced leukocytic response, including stasis in sinusoids as well as rolling and adherence in postsinusoidal venules with subsequent tissue infiltration. Moreover, rG-CSF, which did not affect Kupffer cell activity in normal rat livers, reduced the immediate activation of Kupffer cells on LPS exposure, as indicated in vivo by the delayed adherence/phagocytosis of intra-arterially administered latex particles associated with attenuation of proinflammatory cytokine release (tumor necrosis factor alpha and interleukin-6). Finally, rG-CSF reduced LPS-induced nutritive perfusion failure and hepatocellular excretory dysfunction. This study provides evidence for a distinct, possibly tumor necrosis factor alpha-dependent modulation of LPS-induced cellular response within the liver by rG-CSF, thereby achieving protection against microcirculatory perfusion failure and hepatic dysfunction. 相似文献
993.
Root surface caries is prevalent in patients with both treated and untreated periodontal disease. The major etiologic factor has been identified as microbial plaque. In periodontally treated patients, significantly higher root caries prevalence and incidence have been found in patients with high levels of Streptococcus mutans and Lactobacilli in saliva. Reducing the levels of S. mutans and Lactobacilli in saliva may lower the risk of root caries development. The purpose of this investigation was to determine the effect of an oral enzymatic rinse on the salivary counts of S. mutans and Lactobacilli in periodontally treated patients. Fifteen adult subjects participated in a double-blind, cross-over designed clinical trial. Each subject had previously undergone comprehensive periodontal therapy and had been maintained on a regular program of supportive periodontal therapy. Paraffin-stimulated whole saliva was collected from each participant. Each subject was then randomly given either the enzymatic rinse product or a control rinse and instructed to rinse with one tablespoonful twice a day for 2 weeks, after which saliva samples were taken. After a washout period, salivary samples were again taken, and the subjects received the alternate rinse product. Two weeks later, final salivary samples were taken. The salivary samples were serially diluted and incubated aerobically on selective culture media. S. mutans and Lactobacilli were counted on the basis of colonial morphology. Pretreatment and posttreatment salivary counts of S. mutans and Lactobacilli were analyzed using the Wilcoxon matched-pairs signed-rank test at the 5% level of significance. Analysis of data revealed that neither the test nor the control rinse significantly lowered salivary counts of either species in the sample population. 相似文献
994.
OBJECTIVE: To evaluate the predictive value of standard letters of recommendation (LORs) vs preprinted questionnaires (PPQs) for resident performance at one emergency medicine (EM) residency program. METHODS: A retrospective association of LORs and PPQs with in-training residents performance ratings was done at one EM residency program. The residency application files of EM residents who completed the program were reviewed to locate files that had LORs and PPQs written by the same author. Seventeen resident files contained 32 LOR/PPQ pairs. These LORs and PPQs were submitted in a blinded fashion to 3 outside EM residency directors. Each LOR and PPQ was evaluated for the applicant's suitability for the specialty of EM, medical knowledge, procedural skills, interpersonal skills, motivation, and overall rank. The scores given by the outside reviewers were compared with resident performance ratings determined by 5 EM attending physicians who evaluated the residents along the same 6 dimensional ratings. RESULTS: Statistically, no differences were found between the LORs and PPQs in predicting resident performance. CONCLUSIONS: PPQs may substitute for LORs in the evaluation of resident applicants. 相似文献
995.
Stevens-Johnson syndrome, related to carvedilol use, has not been previously reported as a serious adverse experience requiring hospitalization. We report this reaction in a 71-year-old man with stable ischemic cardiomyopathy. 相似文献
996.
MM Haznedar MS Buchsbaum C Luu EA Hazlett BV Siegel J Lohr J Wu RJ Haier WE Bunney 《Canadian Metallurgical Quarterly》1997,154(5):682-684
Although the majority of physicians entering residency training in Canada will enjoy fulfilling careers in their chosen specialty, today's postgraduate training system has its critics. Among them are the new graduates who are not satisfied with the residency positions offered to them and practising physicians who would like to re-enter the system to train in a new specialty but find themselves locked out. 相似文献
997.
998.
J Stiles M McDermott M Willis W Roberts C Greene 《Canadian Metallurgical Quarterly》1997,58(8):804-807
OBJECTIVE: To compare nested polymerase chain reaction (PCR), virus isolation (VI), and fluorescent antibody (FA) testing to detect feline herpesvirus (FHV) in cats with naturally acquired conjunctivitis or respiratory tract disease, or both. SAMPLES: Swab and microbrush specimens from the conjunctiva and throat were taken from 46 cats, allotted to 3 groups (conjunctivitis only, respiratory tract disease and conjunctivitis, and clinically normal). PROCEDURE: Cells from microbrush specimens were digested and herpesvirus DNA was amplified, using a double round of PCR. Products were detected by use of agarose gel electrophoresis. The VI and FA tests were performed in routine manner. RESULTS: Of 16 cats with conjunctivitis only, conjunctival specimens from 8 and throat specimens from 8 were FHV positive by PCR. None had positive results of VI or FA testing. Of 15 cats with respiratory tract disease and conjunctivitis, conjunctival specimens from 13 and throat specimens from 12 were FHV positive by PCR. A conjunctival specimen from 1 cat and throat specimens from 3 cats were FHV positive by VI. A conjunctival specimen from 1 cat was FHV positive by FA testing. Of 15 clinically normal cats, conjunctival and throat specimens from 2 cats were FHV positive by PCR; neither conjunctival nor throat specimens from these cats were FHV positive by VI or FA testing. CONCLUSION: For cats with respiratory tract disease and conjunctivitis, or with conjunctivitis only, nested PCR was more sensitive at detecting FHV than was VI or FA testing. CLINICAL RELEVANCE: Nested PCR is a more sensitive test than the currently available VI and FA tests for identifying FHV in cats with conjunctivitis. 相似文献
999.
Glut-2 is a low-affinity transporter present in the plasma membrane of pancreatic beta-cells, hepatocytes and intestine and kidney absorptive epithelial cells of mice. In beta-cells, Glut-2 has been proposed to be active in the control of glucose-stimulated insulin secretion (GSIS; ref. 2), and its expression is strongly reduced in glucose-unresponsive islets from different animal models of diabetes. However, recent investigations have yielded conflicting data on the possible role of Glut-2 in GSIS. Whereas some reports have supported a specific role for Glut-2 (refs 5,6), others have suggested that GSIS could proceed normally even in the presence of low or almost undetectable levels of this transporter. Here we show that homozygous, but not heterozygous, mice deficient in Glut-2 are hyperglycaemic and relatively hypo-insulinaemic and have elevated plasma levels of glucagon, free fatty acids and beta-hydroxybutyrate. In vivo, their glucose tolerance is abnormal. In vitro, beta-cells display loss of control of insulin gene expression by glucose and impaired GSIS with a loss of first phase but preserved second phase of secretion, while the secretory response to non-glucidic nutrients or to D-glyceraldehyde is normal. This is accompanied by alterations in the postnatal development of pancreatic islets, evidenced by an inversion of the alpha- to beta-cell ratio. Glut-2 is thus required to maintain normal glucose homeostasis and normal function and development of the endocrine pancreas. Its absence leads to symptoms characteristic of non-insulin-dependent diabetes mellitus. 相似文献
1000.
The use of either direct or indirect genetic analyses in neurology is becoming ever greater as more genes are identified thanks to the human genome project. Often the methodologies are complex and difficult to understand. The aim of this review is to present various approaches to molecular diagnosis using several different inherited neurological diseases as examples. These include inherited mitochondriopathies, monogenetic disorders like trinucleotid repeat instability syndromes, duplication anomalies and specific point mutations as well as heterogenetic diseases such as limb girdle dystrophy and familial amyotrophic lateral sclerosis. Possible pathogenetic implications can now be proposed as the basis of new therapeutic modalities. 相似文献