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91.
A child is described with a de novo interstitial deletion of band 2p22 and a reciprocal translocation (3;7)(p21;q22). The child has mild developmental delay, coloboma of the right eye, and Hirschsprung's disease. The clinical and cytogenetic findings are described.  相似文献   
92.
Lactobacillus fermentum NCTC 6991 and Lactobacillus plantarum NCIB 7220 were grown in a chemostat in the diffusible fraction of complex medium at pH 6.0 with glucose limitation. Organisms grown at different dilution rates (D) were injected into rabbits, and the resultant antisera were examined for reactivity with antigens previously isolated from batch-grown organisms. For L. fermentum, antisera obtained on injecting cells grown at D = 0.5 h-1 contained a significantly higher level of antibody reacting with lipoteichoic acid and a lower level of antibody reacting with wall polysaccharide than did antisera obtained with slower-growing cells (D = 0.05 and 0.033). Antibodies to the cell wall polysaccharide were alpha-D-glucosyl specific and cross-reacted with dextran and alpha-D-glucosyl ribitol teichoic acid from L. plantarum. The immunogenicity of the ribitol teichoic acid and lipoteichoic acid components of L. plantarum was not influenced by injecting organisms grown at different rates. However, chemical and serological studies indicate that growth of L. plantarum in the diffusible fraction of complex medium results in a wall teichoic acid of lower glucose substitution. This apparently influences the specificity of the resultant antibodies so that some sera react much less with glucosyl-substituted lipoteichoic acid and dextran.  相似文献   
93.
Rapid detection of vancomycin-resistant enterococci.   总被引:4,自引:12,他引:4       下载免费PDF全文
Campylobacter blood agar with clindamycin incubated in 6% CO2 served as a medium to both screen for vancomycin resistance and select for presumptive enterococci. Colonies that grew on the medium were specifically identified as enterococci within 30 min by the pyroglutamyl-beta-naphthylamide and rapid bile esculin tests. The combination of a selective medium plus rapid enzyme substrate tests offered an inexpensive means to enumerate vancomycin-resistant enterococci from specimens by using readily available reagents.  相似文献   
94.
A case of postoperative prosthetic hip joint infection due to Campylobacter fetus subsp. fetus is described. Difficulties in isolation and antimicrobial susceptibility testing of this organism are discussed.  相似文献   
95.
BACKGROUND. The idiotypic determinants of the surface immunoglobulin of a B-cell lymphoma can serve as a clonal tumor-specific marker, which may have implications for immunotherapy. We sought to determine whether idiotype-specific immune responses against this autologous antigen could be induced in patients with B-cell lymphoma. METHODS. Nine patients were selected who had minimal residual disease or a complete remission after chemotherapy. Each received a series of subcutaneous injections of the immunoglobulin derived from his or her tumor cells (immunoglobulin-idiotype protein), which had been conjugated to a protein carrier and mixed with an immunologic adjuvant. RESULTS. In seven of the nine patients the injections induced sustained idiotype-specific immunologic responses of the humoral type (two patients), the cell-mediated type (four patients), or both (one patient). The use of an adjuvant was essential for these immune responses. The induced antibodies bound specifically to autologous immunoglobulin idiotype, inhibited the binding of murine monoclonal antiidiotype antibodies, and bound autologous tumor cells. Cell-mediated responses were demonstrated by the specific proliferation of immune peripheral-blood mononuclear cells to the soluble immunoglobulin-idiotype protein in vitro. The tumors of both of the patients with measurable disease regressed completely. Toxicity associated with the vaccine was minimal and consisted only of mild reactions at the site of intramuscular injection. CONCLUSIONS. These results demonstrate that autologous immunoglobulin idiotype can be formulated into an immunogenic, tumor-specific antigen in humans with B-cell lymphoma, and they provide the background for large-scale trials of active specific immunotherapy of this disease.  相似文献   
96.
Computers have gained rapid acceptance in general practice. A recent development has been the use of computers to run practice appointment systems. This study demonstrates the benefits of installing a computerized appointment system, with improved service for patients, and more efficient use of time by both doctors and receptionists.  相似文献   
97.
Isoflavones are plant compounds, proposed to have health benefits in a variety of human diseases, including coronary heart disease and endocrine-responsive cancers. Their physiological effects include possible antioxidant activity, therefore suggesting a role for isoflavones in the prevention of male infertility. The aim of this study was to test the antioxidant effects of the isoflavones genistein and equol on sperm DNA integrity, assessed in vitro after hydrogen peroxide-mediated damage, using the comet assay. Pre-treatment with genistein or equol at doses of 0.01-100 micromol/l significantly protected sperm DNA against oxidative damage. Both ascorbic acid (10-600 micromol/l) and alpha-tocopherol (1-100 micromol/l) also protected. Compared with ascorbic acid and alpha-tocopherol, added at physiological concentrations, genistein was the most potent antioxidant, followed by equol, ascorbic acid, and alpha-tocopherol. Genistein and equol added in combination were more protective than when added singly. Based on these preliminary data, which are similar to those observed previously in lymphocytes, these compounds may have a role to play in antioxidant protection against male infertility.  相似文献   
98.
99.
Facial expression recognition by people with mobius syndrome   总被引:1,自引:0,他引:1  
We present an investigation of facial expression recognition by three people (BC, LP, and NC) with Mobius syndrome, a congenital disorder producing facial paralysis. The participants were asked to identify the emotion displayed in 10 examples of facial expressions associated with each of 6 basic emotions from the Ekman and Friesen (1976) series. None of the three people with Mobius syndrome was significantly impaired on this task. On a second test of facial expression recognition using computer-morphed facial expressions, NC showed a statistically significant impairment, BC a borderline deficit, and LP was unimpaired. However, even when impairments were found, people with Mobius syndrome still recognised many of the facial expressions shown to them. The recognition of facial expressions by people who have never been able to produce such signals on their own faces demonstrates that the ability to produce facial expressions is not a necessary prerequisite of their recognition.  相似文献   
100.
A blood culture cohort study investigating issues related to isolation of coagulase-negative staphylococci (CoNS) and other skin microflora is reported. Data were collected over 12 weeks to determine the incidence of significant CoNS bacteremia versus that of pseudobacteremia (contaminants) and to evaluate drug therapy in patients with cultures positive for CoNS. In addition, the effectiveness of 0.2% chlorine peroxide as a bactericidal disinfectant was compared to that of 10% providone iodine. A total of 3,276 cultures of blood from 1,433 patients were evaluated in the study. Eighty-nine cultures were positive for skin flora, with 81 of 89 (91%) involving CoNS. The incidence of significant CoNS bacteremia was 20 of 81 (24.7%), that of indeterminate bacteremia was 10 of 81 (12.3%), and that of contamination was 59 of 81 (72.8%). The incidence of significant bacteremia involving CoNS was double the 10 to 12% rate based on previous estimations at our institutions. In tests with the two bactericidal disinfectants, 22 of 1,639 cultures (1.3%) in the chlorine peroxide group versus 37 of 1,637 (2.3%) in the providone iodine group were considered contaminated (P = 0.065). Rates of contamination for venipuncture versus catheter collection were not significantly different (P = 0.46). The overall contamination rate was 59 of 3,276 (1.8%), which is consistent with the lower end of published quality assurance benchmark standards. The low rate was believed to be due to the professional phlebotomy staff in our institutions. There was excellent agreement between retrospective analysis by reviewers, when formal criteria were used, and the attending physicians’ intuitive clinical impressions in the classification of significant bloodstream infections (100% agreement) or contamination (95% agreement). However, physicians still used antimicrobial agents to treat nearly one-half of the patients with contaminated blood cultures, with vancomycin being misused in 34% of patients. In addition, 10% of patients with significant bacteremia were treated with inappropriate agents. There were no significant adverse events or prolonged hospital stays due to the unnecessary use of vancomycin; however, the additional costs of treating patients whose cultures contained CoNS contaminants was estimated to be $1,000 per patient. Measures to limit the unnecessary use of vancomycin (and other agents) are important.Coagulase-negative staphylococci (CoNS), the most frequent blood culture isolates, are predominantly blood culture contaminants, but they are also a significant cause of bacteremia (25, 7, 9, 13). Institution-specific contamination rates vary from 2 to more than 6% (3, 5, 23, 26, 27). In the past 5 years, estimated contamination rates at our hospitals ranged from 2.5 to 3.5%. During this period, CoNS accounted for 45 to 60% of total blood isolates, and we estimated, using laboratory criteria, that 10 to 12% of CoNS isolates from blood were implicated in significant bloodstream infections. A relatively large proportion of the patient population with presumed false-positive blood cultures due to contaminants (pseudobacteremia) were treated with antimicrobial agents, in particular, vancomycin.Clinical and microbiologic guidelines for the differentiation of true bacteremia from pseudobacteremia or contamination have been published (5, 13, 15). Suggested laboratory criteria for true bacteremia include growth within 48 h and multiple blood cultures positive for the same organism. In contrast, increased duration of time before positivity, polymicrobial growth of skin organisms, or growth during antibiotic treatment suggest contamination. Others recommended that the addition of clinical guidelines is essential for the appropriate classification of bacteremia (4, 8, 9, 15, 18).We conducted a cohort study to evaluate clinical and laboratory data for adult patients with blood cultures positive for CoNS. The study was done at two tertiary-care teaching centers, Deaconess Medical Center (DMC) and Sacred Heart Medical Center (SHMC), with a combined capacity of 900 beds. We examined problems associated with false-positive bacteremia and determined the incidence of significant bacteremia. Our goal was to make recommendations to improve clinicians’ ability to recognize the significance of potentially contaminating organisms and to evaluate treatment given to patients with CoNS-positive blood cultures. To attempt to minimize contamination, we evaluated the nontoxic, antiseptic and disinfectant chlorine peroxide in comparison to a standard disinfectant.(This work was previously presented in abstract form at the 96th General Meeting of the American Society for Microbiology, New Orleans, La., 19 to 23 May 1996 [24a].)  相似文献   
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