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901.
Vasa praevia is a rare complication of pregnancy associated with a high fetal morbidity and mortality. As planned caesarean section can circumvent fetal risks, early detection of vasa praevia is desirable. Antenatal diagnosis by ultrasound by visualisation of vasa praevia may be difficult by transvaginal sonography alone due to an unfavourable angle of insonation. Combination of transabdominal and transvaginal sonography is superior in imaging the placental type, location, insertion of the cord and vasa praevia. We present four cases of antepartum and one case of intrapartum diagnosis of vasa praevia in singleton pregnancies using transabdominal and transvaginal colour coded Doppler sonography. A bipartite placenta with normal cord insertion was found in three cases and with velamentous insertion of the cord in one case. One case had a partially membranous placenta with velamentous insertion of the cord. From the site of cord insertion fetal vessels were coursing over the internal cervical os and then continued in an amniotic sheet to the main placental mass on the opposite uterine wall. 相似文献
902.
WL Nicholson 《Canadian Metallurgical Quarterly》1995,31(6):361-364
Photoreactivation of ultraviolet radiation-induced DNA damage was examined in exponential-phase cells of six mesophilic species of the genus Bacillus. Under the experimental conditions used, it was observed that the laboratory strains B. cereus strain T and B. thuringiensis var. thuringiensis strain NRRL-B4039 exhibited strong photoreactivation (86-fold and 70-fold respectively). Bacillus licheniformis strain ATCC 8480 exhibited moderate (15-fold) photoreactivation. Weak photoreactivation was observed in B. subtilis strain 168 (4-fold) and B. megaterium strain QM B1551 (3.4-fold). Bacillus amyloliquefaciens strain H demonstrated no detectable photoreactivation. 相似文献
903.
WA Ferens WL Goff WC Davis LK Fox C Deobald MJ Hamilton GA Bohach 《Canadian Metallurgical Quarterly》1998,7(3):193-213
Persistent intramammary infections of dairy cows with Staphylococcus aureus may involve immunosuppression mediated by bacterial toxins such as enterotoxins and other super-antigens (SAgs). Previously we found that stimulation of bovine PBMC with staphylococcal enterotoxin C (SEC) induced a unique phenotype of activated CD8+ T cells expressing a newly identified activation molecule, ACT3. In the present study we found that SEC induced the expression of interleukin (IL)-4 and IL-10 mRNAs, two cytokines associated with type 2 responses. Elevated levels of IL-4 and IL-10, observed between day 0 and day 4 of culture, were associated with temporary inhibition of proliferative responses of T cells, evidenced by a decrease in numbers of CD4+ T cells and a small increase in numbers of CD8+ T cells. Vigorous proliferation of T cells occurred between days 4 and 7 of culture and with a bias towards CD8+ T cells. Acquisition of the ACT3+ phenotype by CD8+ T cells was preceded by induction of IL-4 mRNA. Thus, in the bovine system, SAgs may hinder protective responses by inducing type 2 cytokines, which interfere with immune clearance of many microbial pathogens. The results of the study are consistent with the hypothesis that SAgs are involved in immunosuppression, and suggest possible immunomodulatory mechanisms. 相似文献
904.
A rapid, specific method for measuring gentamicin in plasma by high-pressure liquid chromatography was developed. After deproteinization, gentamicin in the supernate was dansylated and extracted into ethyl acetate. The organic extract was chromatographed on a microparticulate reversed-phase column, which was eluted with aqueous acetonitrile. Use of the dansyl derivative enables fluorometry, for more sensitive quantitation. Various factors that could affect the assay sensitivity were investigated. With 0.2-ml plasma samples, the method can accurately measure as little as 1 mg of gentamicin per liter. We encountered no interferences from plasma supplemented with various drugs or plasma of patients who were on therapy with other drugs. This method can also separate gentamicin C1 from C1a and C2, all of which are present in various ratios in commercial dosage forms. This method is also applicable to gentamicin determination in urine. 相似文献
905.
JA Foekens MP Look HA Peters WL van Putten H Portengen JG Klijn 《Canadian Metallurgical Quarterly》1995,87(10):751-756
BACKGROUND: Urokinase-type plasminogen activator (uPA) is a proteolytic enzyme thought to be involved in processes leading to tumor cell invasion of surrounding tissues. Its activity during metastasis may be regulated by an inhibitor, PAI-1. Previous work has shown that high levels of uPA and PAI-1 are associated with poor prognosis in primary breast cancers. PURPOSE: In this pilot study, we explored possible associations between the expression levels of uPA or PAI-1 and the efficacy of tamoxifen treatment in breast cancer patients with relapsed disease. METHODS: Levels of uPA, PAI-1, estrogen receptor (ER), and progesterone receptor (PgR) were assayed in cytosolic extracts derived from the primary breast tumors of 235 tamoxifennaive patients who had recurrent disease. The extracts were classified as positive or negative for each assayed factor. In some analyses, ER and PgR levels were evaluated together. In these analyses, three ER/PgR subsets were defined: low, intermediate, and high. All patients in the study received tamoxifen therapy upon relapse (median follow-up, 57 months). Association of the tested factors with the response to tamoxifen treatment was studied by logistic regression analysis. Association of the factors with progression-free and overall survival was further evaluated by Cox univariate and multivariate regression analyses. RESULTS: Patients with uPA-negative tumors exhibited a better response (tumor regression or stable disease, maintained for more than 6 months) to tamoxifen treatment than those with uPA-positive tumors (51% versus 26% response; odds ratio [OR] = 0.34; 95% confidence interval [CI] = 0.18-0.65). The response rate was also better for patients with PAI-1-negative tumors than for those with PAI-1-positive tumors (49% versus 35% response; OR = 0.57; 95% CI = 0.32-1.01). In addition, patients with uPA-positive or PAI-1-positive tumors showed shorter progression-free survival (P = .001 and P < .05, respectively) and total survival after relapse (P = .005 and P < .005, respectively). When patients were stratified by ER/PgR status, the only statistically significant association between uPA levels and reduced tamoxifen response was seen in the subset whose tumors possessed intermediate levels of ER/PgR (16% response in uPA-positive versus 60% response in uPA-negative tumors; OR = 0.13; 95% CI = 0.04-0.41). Overall, uPA status appeared independent of association with ER/PgR status in its ability to predict response to tamoxifen treatment. The association of PAI-1 expression and the response to tamoxifen was less pronounced when patients were stratified by ER/PgR status. CONCLUSION: Measurement of primary breast tumor uPA levels may be useful in predicting the overall response of metastatic disease to tamoxifen therapy. 相似文献
906.
For the diagnosis of lumbar P.I.D. discography is much superior to myelography. The risks of both techniques are the same, but the side-effects of discography are clearly less. Higher lesions remain a problem if they do not show up neurologically (s. the prolapsed disc at L 2/3). Here segmental blocking, posterior gaping of the intervertebral space and displacement of the dural sac show clearly the posterior prolapse. In the standard discogram of the lower 3 discs it would have been missed. In spite of this our present experience with lumbar discography is so positive, that we are about to test a long term series, whether and to which extend discography could replace myelography in cases where there is no hint at a space-occupying lesion, other than a disc or whether the order of these investigations should be reversed. 相似文献
907.
Anti-Lu 14 has been found in the serum of a gravida 2 pregnant woman who had not been given any blood transfusions. Her husband is Lu:14 but otherwise of common Lutheran blood type. Maternal immunization probably occurred during the first pregnancy. The second child did not inherit the father's Lu14 gene and was not affected by the maternal antibody. 相似文献
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