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101.
OBJECTIVE: To estimate the seroprevalence of HHV-8 in several Spanish subpopulations with different risk levels of acquiring HIV-1 infection and from different geographical regions. DESIGN: Cross-sectional seroprevalence study. METHODS: A total of 1699 serum samples from blood donors (613), children under the age of 12 years (100), injecting drug users (IDU) (382), heterosexuals attending a sexually transmitted disease (STD) clinic (273) and homosexual men attending a STD clinic or a HIV-based hospital unit (331) were analysed for anti-HHV-8 antibodies. The presence of antibodies against HHV-8 was tested with an indirect immunofluorescence assay (IFA). A subsample of HHV-8-positive samples was also tested for antibody titre against HHV-8. RESULTS: The overall seroprevalence of antibodies against HHV-8 for the blood donor population was 6.5% (7.0% in Andalusia, 8.0% in Catalonia and 4.5% in the Basque Country). None of the children tested positive for HHV-8. The HHV-8 prevalence was 86.7% in HIV-positive homosexual men and 28.0% in HIV-negative homosexual men (P < 0.001). Of heterosexual men attending STD clinics, 17.2% tested positive for HHV-8; 11.5% of IDU tested positive for HHV-8. HHV-8 antibody titres by groups parallel the distribution of HHV-8 prevalence. No association between HHV-8 antibody titres and CD4 cell count or HIV viral load was identified. CONCLUSIONS: The HHV-8 prevalence among blood donors in Spain is higher than in Northern Europe and the USA, but is similar to that in Northern Italy. The distribution of HHV-8 is compatible with a sexually transmitted agent. The distribution of HHV-8 correlates with that of Kaposi's sarcoma but factors other than HHV-8 seem to explain the Kaposi sarcoma distribution.  相似文献   
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Studies investigating dental arch spatial changes following first primary molar premature loss are controversial regarding clinical significance. The purpose of this review was to systematically investigate the relevant literature. Controlled studies investigating changes before and after premature loss of first primary molars were searched in various databases. Split-mouth design studies were considered eligible for inclusion. The risk of bias was judged according to ADA Clinical Practice Guidelines. Only two analyzable split-mouth studies on mandibular first primary molar loss were identified. Space loss in the extraction side was greater at 2, 4, 6 and 8-month follow-ups, reaching a ?1.5 mm difference in the final examination (95% Confidence Interval: ?2.080 to ?0.925; p = 0.000; random effects model). Studies were judged to be at unclear risk of bias. The amount of space decrease after premature loss of first primary molars may have management implications under certain circumstances. Comprehensive assessment of the various characteristics of each patient should precede management decisions in individual cases.  相似文献   
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Crohn’s disease (CD) diagnosis is a tremendously serious health problem due to its ultimately effect on the gastrointestinal tract that leads to the need of complex medical assistance. In this study, the backpropagation neural network fuzzy classifier and a neuro-fuzzy model are combined for diagnosing the CD. Factor analysis is used for data dimension reduction. The effect on the system performance has been investigated when using fuzzy partitioning and dimension reduction. Additionally, further comparison is done between the different levels of the fuzzy partition to reach the optimal performance accuracy level. The performance evaluation of the proposed system is estimated using the classification accuracy and other metrics. The experimental results revealed that the classification with level-8 partitioning provides a classification accuracy of 97.67 %, with a sensitivity and specificity of 96.07 and 100 %, respectively.  相似文献   
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Background: There is evidence suggesting that atrial fibrillation (AF) may be induced by acute increase of atrial pressure. The aim of the present study was to investigate the effect of alterations in atrial pressure, induced by varying the atrioventricular (AV) interval, on atrial refractoriness, and on the frequency of induction of (AF), in patients with a history of lone atrial fibrillation (LAF).Methods and Results: Twenty-five patients were included in this study. The patients were divided in two groups: the LAF group, and the control group. None of the patients in either group had organic heart disease. Effective refractory period (ERP) and duration of atrial extrastimulus electrogram (A2) were measured at two right atrial sites (high lateral wall, atrial appendage) during AV pacing (cycle length: 500 msec) with different AV intervals. Peak, minimal and mean atrial pressure increased from 8.57 ± 2.37 to 18.14 ± 4.74 mm Hg, 2 ± 2.23 to 5.14 ± 2.60 mm Hg (p = 0.0001) and from 4.28 ± 1.6 mm Hg to 9.77 ± 2.9 mm Hg (p = 0.001), respectively during AV interval modification. During lateral and atrial appendage pacing, with a progressive decrease of AV interval to 160, 100, 80, 40, 0 msec, the ERP, the dispersion of ERP, functional refractory period (FRP), A2 and latency period (LP) did not change significantly, in both groups. The frequency of induction of AF was not statistically different in both lateral atrial wall and appendage, during pacing in different AV intervals.Conclusions: This study demonstrates that alterations in the intraatrial pressure does not have important effects on atrial refractoriness and does not increase vulnerability to AF in patients with a history of LAF.  相似文献   
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Zoledronic acid is a nitrogen-containing, third-generation bisphosphonate that has recently been approved for the treatment of postmenopausal osteoporosis as an annual intravenous infusion. Zoledronic acid is an antiresorptive agent which has a high affinity for mineralized bone and especially for sites of high bone turnover. Zoledronic acid is excreted by the kidney without further metabolism. Zoledronic acid administered as a 5 mg intravenous infusion annually increases bone mineral density in the lumbar spine and femoral neck by 6.7% and 5.1% respectively and reduces the incidence of new vertebral and hip fractures by 70% and 41% respectively in postmenopausal women with osteoporosis. Most common side effects are post-dose fever, flu-like symptoms, myalgia, arthralgia, and headache which usually occur in the first 3 days after infusion and are self-limited. Rare adverse effects include renal dysfunction, hypocalcemia, atrial fibrillation, and osteonecrosis of the jaw.  相似文献   
107.
The purpose of the study was to evaluate the efficacy of conservative surgical treatment of medication related osteonecrosis of the jaw (MRONJ) in patients affected by osteoporosis and exposed to oral bisphosphonates (BPs).Subjects diagnosed with MRONJ and osteoporosis under oral BPs that had undergone conservative surgery and had at least 24 months follow-up were included. All patients received medical-antibiotic therapy and then underwent conservative surgical treatment consisting of sequestrectomy, soft tissue debridement and bone curettage with limited or no extension.A total of 53 patients, mean age of 71.9 ± 10.2 years (range 41–87), were enrolled. Two years after conservative surgical therapy 45 patients (91.8%) showed complete healing. The presence of rheumatoid arthritis (p = 0.003) and a more severe initial MRONJ stage (p = 0.023) were associated with a negative surgical outcome while the presence of bone sequestrum was strongly associated with a positive outcome (p = 0.036).Conservative surgical treatment of MRONJ lesions in patients affected by osteoporosis and receiving only oral BPs may represent a valid therapeutic approach determining a high number of complete healing cases. Conservative surgery should be encouraged at early MRONJ stages and after medical therapy failure.  相似文献   
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