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991.
The recovery of Clostridium difficile from the stools of patients with C. difficile-associated diarrhea was evaluated by use of an enrichment broth (cycloserine-cefoxitin fructose broth supplemented with 0.1% sodium taurocholate [TCCFB]) and was compared to that from selective agar (cycloserine-cefoxitin fructose agar [CCFA]) and alcohol shock followed by inoculation onto blood agar (AS-BA). TCCFB was superior to CCFA and AS-BA, and neither the storage time nor the storage temperature affected the recovery rate.  相似文献   
992.
Currently available methods for the diagnosis of cutaneous leishmaniasis (CL) have low sensitivities or are unable to quantify the number of viable parasites. This constitutes a major obstacle for the diagnosis of the disease and for the study of the effectiveness of treatment schedules and urges the development of improved detection methods. In this study, quantitative nucleic acid sequence-based amplification (QT-NASBA) technology was used to detect and quantify Leishmania parasites in skin biopsy samples from CL patients. The assay is based on the detection of a small subunit rRNA (18S rRNA), which may allow for the detection of viable parasites. The QT-NASBA assay was evaluated using in vitro-cultured promastigotes and amastigotes and 2-mm skin biopsy samples from Old and New World CL patients. The study demonstrated that the lower detection limit of the QT-NASBA was two parasites per biopsy sample. Parasites could be quantified in a range of 2 to 11,300,000 parasites per biopsy sample. The QT-NASBA could detect levels of parasites 100-fold lower than those detected by conventional PCR. Test evaluation revealed that the QT-NASBA had a sensitivity of 97.5% and a specificity of 100% in the present study. The QT-NASBA is a highly sensitive and specific method that allows quantification of both Old and New World Leishmania parasites in skin biopsy samples and may provide an important tool for diagnosis as well as for monitoring the therapy of CL patients.  相似文献   
993.
994.
Although research on DNIC has revealed the inhibitory effect occurring between two remote pain stimuli, the interrelation between two adjacent painful stimuli has not yet been characterized. In the present study, we used a sample of 40 healthy volunteers to examine the effect of 30-s immersion of the fingers in water of 1 °C, as a conditioning stimulus, on pain intensities produced by conditioned mechanical punctuate stimuli, applied both adjacent and contralateral to the cooled area. There was a significant decrease in mechanical pain intensities from 17.23 ± 2.39 at baseline to 12.45 ± 2.39 when stimulating immediately after the cold immersion at an adjacent site, and from 20.00 ± 2.39 to 15.08 ± 2.39 at remote sites (F = 20.02, p < 0.0001). A significant positive correlation between the extent of pain reduction in the cooled and in the uncooled hand was found (rs = 0.59, p = 0.0001). The extent of pain reduction following cooling in the cooled and in the uncooled hand was also found to be similar for males and for females (p = 0.63). It is concluded that under the conditions of this experiment, EA affects heterotopic and homotopic regions similarly and without gender differences.  相似文献   
995.
996.
Objective: To evaluate clinical outcomes of women with singleton pregnancies that underwent intra-amniotic dye instillation (amniodye test) following equivocal diagnosis of prelabor rupture of membranes (PROM).

Method: Records of 34 pregnant women who underwent amniodye test for equivocal PROM were reviewed. Comparisons of characteristics, amniotic fluid (AF) cultures, AF interleukin (IL)-6 concentrations, and placenta pathology results between women who tested positive and those who tested negative were performed. A sub-analysis of women who were amniodye test-negative was also performed.

Results: (1) Commonest indication for amniodye test was a typical history of PROM with positive conventional tests and persistently normal AF volume, (2) amniodye test-positive women had a shorter procedure-to-delivery interval (p?=?0.008), and a greater proportion of histologic acute chorioamnionitis (p?=?0.04) and funisitis (p?=?0.01) than amniodye-negative women, and (3) in addition to similarities to women with amniodye-positive test, amniodye test-negative women who delivered <34 weeks, had a greater proportion of women with risk for preterm birth (p?=?0.04), than their counterparts who delivered between 34 0/7 and 36 6/7 weeks.

Conclusion: Equivocal diagnosis of PPROM should warrant an amniodye test to avoid iatrogenic intervention in women with intact amniotic membranes. AF analysis should be performed in amniodye test-negative women.  相似文献   
997.
Objectives: “Heart sparing” refers to prominent antegrade fetal coronary artery (CA) blood flow readily visualized by color Doppler and is a harbinger of poor outcome in growth restricted fetus, but little is known of the features and presentation of heart sparing in normally grown fetuses. Our objective was to describe heart sparing effects in normally grown fetuses, and compare the presentation and outcome of heart sparing between fetuses with growth restriction and those who were normally grown.

Methods: In a series of fetuses with prominent antegrade CA flow, we assessed Doppler flow profiles in the aortic isthmus, ductus venosus (DV), umbilical vein (UV), umbilical artery (UA) and middle cerebral artery (MCA). We calculated MCA and UA systolic/diastolic ratios and the cerebral placental ratio, and measured fetal biometry. We evaluated cardiac function using the myocardial performance index (MPI) and the cardiovascular profile score (CVPS).

Results: Ten fetuses with heart sparing had normal DV flow at 24–36.6 (mean 30.9) weeks of gestation. Five had growth restriction (Group 1); 4/5 had normal MPI and CVPS, and one died. Five were normally grown (Group 2); 5/5 had elevated MPI and decreased CVPS, of these 2 died in utero and one died immediately after birth despite urgent delivery. Coronary arteries were normal after birth or autopsy.

Conclusions: Heart sparing confers a poor prognosis in fetal growth restriction and in normally grown fetuses with cardiac dysfunction. We suggest CA flow be assessed in all high-risk fetuses.  相似文献   
998.
999.
1000.
Co-stimulatory molecules are key mediators in the regulation of immune responses and knowledge of its different families, structure, and functions has improved in recent decades. Understanding the role of co-stimulatory molecules in pathological processes has allowed the development of strategies to modulate cellular functions. Currently, modulation of co-stimulatory and co-inhibitory molecules has been applied in clinical applications as therapeutic targets in diseases and promising results have been achieved.  相似文献   
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