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1.
Although the influence of the menstrual cycle on both vaginal candidosis and Candida albicans adherence to vaginal epithelial cells in vitro has been shown to be significant, similar studies have not been made on oral candidosis and adherence to buccal epithelial cells. The aim of this study was therefore to use an in vitro adherence assay to investigate the possible influence of the menstrual cycle on the adherence of C. albicans to buccal epithelial cells. Epithelial cells were collected from a single, healthy, female volunteer on days 5, 15, 22 and 28 of six menstrual cycles. Adherence of C. albicans was significantly higher to buccal epithelial cells collected on day 5 of the menstrual cycle when compared with days 15, 22 and 28, both in terms of the percentage of buccal epithelial cells with adherent C. albicans and the number of C. albicans adhering per 200 buccal epithelial cells in four out of six menstrual cycles (p < 0.001). This result indicates that hormonal influences should be considered when buccal epithelial cells are used in vitro to assess candidal adherence and may implicate hormonal factors in the aetiology of oral candidosis.  相似文献   
2.
In this paper we examine the problem of constructing optimal virtual topologies for one-to-many communication in optical networks employing wavelength-division multiplexing. A virtual topology is a collection of optical lightpaths embedded in a physical topology. A packet sent from the source node travels over one or more lightpaths en route to its destination. Within a lightpath, transmission is entirely optical. At the terminus of a lightpath the data is converted into the electronic domain where it may be retransmitted on another lightpath toward its destination. Since the conversion of the packet from the optical to the electronic domain introduces delays and uses limited physical resources, one important objective is to find virtual topologies which minimize either the maximum or average number of lightpaths used from the source to all destination nodes. Although this problem is NP-complete in general, we show that minimizing the maximum or average number of lightpaths in path and ring topologies can be solved optimally by efficient algorithms.  相似文献   
3.
This investigation examined the relationship between gender (client, therapist, and client/therapist dyad) and various psychotherapy-related variables for clients with mood and/or anxiety disorders. In several instances, both client and therapist gender predicted treatment retention and psychological symptom changes during 3 months of therapy. In general, female clients were more likely to advance beyond the initial intake assessment and also complete 3 months of therapy. Conversely, male clients were more likely to withdraw from therapy after the initial intake assessment. Specific client/therapist gender pairing predicted treatment retention in the mood disorder subsample and trait anxiety symptom severity in the anxiety disorder subsample. Some findings should be interpreted with caution, as there were small group samples in a few of the analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Self-assembling Ge(Si)/Si(100) quantum dots   总被引:2,自引:0,他引:2  
The morphological evolution of self-assembled epitaxial quantum dots on Si(100) is reviewed. This intensely investigated material system continues to provide fundamental insight guiding the growth of nanostructured electronic materials. Self-assembled quantum dots are faceted, three-dimensional islands which grow atop a planar wetting layer. Pure Ge growth at higher substrate temperatures results in narrower island size distributions but activates additional strain-relief mechanisms which will alter the optical and electronic properties of the dots. Optical and electrical characterization has shown that electrons and holes are confined to different regions of the dot. This results in a spatially indirect, type II recombination mechanism. Emerging device applications which exploit properties of these nanoscale Ge islands are discussed.  相似文献   
5.
We conducted a prospective nonrandomized study of outpatient therapy with ceftriaxone as a single agent in 50 episodes of fever and neutropenia in children treated with various myelosuppressive regimens for different malignancies. All patients underwent clinical and radiological evaluation and blood/urine cultures taken before starting therapy. Patients with dehydration, hypotension, rigor and clinical exit-site infection of indwelling right-sided catheters were excluded. Forty-one patients completed an antibiotic course of 7 days: in 12 patients fever returned to normal on day 2, in 10 patients on day 3, and in 8 patients on day 4. The duration of neutropenia following the initial febrile episode was 3-10 days. In some patients fever returned to normal after 2 days, but neutropenia persisted up to 10 days. Two patients were bacteremic--Escherichia coli in one, and Acinetobacter/Staphylococcus coagulase negative in another; all isolates were sensitive to ceftriaxone. In nine episodes, antimicrobial therapy was modified because of persistent fever > 39 degrees C in five patients, bacteremia in two, enterocolitis in one, breakthrough fever in two, and bronchopneumonia in one. The low incidence of bacterial isolation is probably attributed to the selection of patients with low risk features. Patients and parents complied with and favored outpatient therapy to hospitalization.  相似文献   
6.
PURPOSE: To study the tolerance of peripherally inserted central catheters (PICCs) of varying sizes and materials to power injection of radiographic contrast agents. MATERIALS AND METHODS: Eight different models of silicone and five different models of polyurethane single-lumen PICCs were injected with increasing rates of iothalamate 60% with use of a power injector. Tolerated and bursting rates and pressures were recorded. RESULTS: There was a wide range of tolerated rates and pressures, depending on the inner and outer diameters of the catheters and on the catheter material. Silicone PICCs tolerated rates between 0.4 and 7.0 mL/sec and polyurethane PICCs tolerated rates between 0.6 and 10.2 mL/sec, depending on the specific catheter. The 5-F silicone PICCs and the 4-F and 5-F polyurethane PICCs tested all tolerated rates greater than 4 mL/sec. Silicone catheters tolerated pressures between 107 and 184 psi, and polyurethane catheters tolerated pressures between 160 and 314 psi. CONCLUSIONS: Larger single-lumen silicone and polyurethane PICCs may be suitable for power injection of contrast agents.  相似文献   
7.
8.
The main objective of the Ambulatory Blood Pressure and Treatment of Hypertension (APTH) trial is to test the hypothesis that antihypertensive treatment based on ambulatory monitoring may be more beneficial than treatment guided by conventional sphygmomanometry. After a 2-month run-in period on single-blind placebo, hypertensive patients were randomized to two groups, one in which the target pressure was a sitting diastolic pressure from 80 through 89 mm Hg on conventional sphygmomanometry (conventional blood pressure [CBP] group), and one in which a daytime (from 10 to 20 h) diastolic pressure from 80 through 89 mm Hg had to be achieved (ambulatory blood pressure [ABP] group). After randomization all patients were started on lisinopril 10 mg/day. One month later lisinopril could be continued at 10 or 20 mg/day or discontinued depending on the attained blood pressure level. This article is an interim report on 207 patients followed for two months into the trial. At one month lisinopril was discontinued more frequently in the ABP than the CBP group (24 vs 9 patients, p = 0.004). Nevertheless at two months, blood pressure control was not significantly different in the two treatment groups. The baseline-adjusted differences in systolic pressure between the two treatment arms of the trial (ABP-CBP group) were +2.7 mm Hg (95% confidence interval [CI]): -2.9, +8.3) for the conventional pressure, +0.4 mm Hg (CI: -4.3, +5.1) for the 24 h pressure, -0.1 mm Hg (CI: -5.1, +4.8) for the daytime pressure and -0.7 mm Hg (CI: -6.7, +5.4) for the night-time pressure. The corresponding differences in diastolic pressure were -1.3 mm Hg (CI: -4, +1.4), +0.1 mm Hg (CI: -3, +3.1), -1.1 mmgH (CI: -4.4, +2.1) and +0.3 mm Hg (CI: -3.7, +4.3), respectively. Thus, the present findings do not refute the APTH research hypothesis. In terms of blood pressure control and the number of patients remaining on antihypertensive drugs, treatment based on ambulatory recordings may be preferable to treatment guided by conventional sphygmomanometry.  相似文献   
9.
Pseudomonas phage MD8 is a temperate phage isolated from the freshwater lake Baikal. The organisation of the MD8 genome resembles the genomes of lambdoid bacteriophages. However, MD8 gene and protein sequences have little in common with classified representatives of lambda-like phages. Analysis of phage genomes revealed a group of other Pseudomonas phages related to phage MD8 and the genomic layout of MD8-like phages indicated extensive gene exchange involving even the most conservative proteins and leading to a high degree of genomic mosaicism. Multiple horizontal transfers and mosaicism of the genome of MD8, related phages and other λ-like phages raise questions about the principles of taxonomic classification of the representatives of this voluminous phage group. Comparison and analysis of various bioinformatic approaches applied to λ-like phage genomes demonstrated different efficiency and contradictory results in the estimation of genomic similarity and relatedness. However, we were able to make suggestions for the possible origin of the MD8 genome and the basic principles for the taxonomic classification of lambdoid phages. The group comprising 26 MD8-related phages was proposed to classify as two close genera belonging to a big family of λ-like phages.  相似文献   
10.
Isolation by distance in Switzerland was detected comparing the surname distributions between Cantons. The decay of isonymy with geographic distance between Cantons was consistent with Malecot's exponential decay of kinship. Lasker's distance was defined as the negative value of the logarithm of isonymy between localities, and it was found that it is linearly and significantly correlated with the log of geographic distance, both within and between languages. The peculiar geographic and linguistic structure of the Confederation, where mountain barriers exist at short distances separating different languages, might explain the rapid changes in surname similarity. It was predicted that the frequency of markers linked to the Y chromosome would show a similar association with distance in Switzerland.  相似文献   
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