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971.
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ObjectiveThe purpose of this study was to determine from which side of the spine the popping sound (PS) emanates during side-lying, rotatory high-velocity low-amplitude (HVLA) thrust manipulation directed to the L5-S1 articulation using a time-frequency analysis. Secondary aims were to calculate the average number of PSs, the duration of lumbar thrust manipulation, and the duration of a single PS.MethodsThirty-four asymptomatic participants received 2 lumbar HVLA thrust manipulations targeting the right and left L5-S1 articulations. Two high sampling rate accelerometers were secured bilaterally 25 mm lateral to the midline of the L5-S1 interspace. For each manipulation, 2 audio signals were extracted and singularly processed via spectrogram calculation to obtain the release of energy over time on each side of the lumbosacral junction.ResultsDuring 60 HVLA thrust manipulations, it was measured a total of 320 PSs. Of those PSs, 176 occurred ipsilateral and 144 occurred contralateral to the targeted L5-S1 articulation; that is, the PS was no more likely to occur on the upside than the downside facet after right or left rotatory L5-S1 HVLA thrust manipulation. Moreover, PSs occurring on both sides at the same time were detected very rarely (ie, 2% of cases) with the lumbar HVLA thrust manipulations. The mean number of audible PSs per lumbosacral HVLA thrust manipulation was 5.27 (range 2-9). The mean duration of a single manipulation was 139.13 milliseconds (95% confidence interval: 5.61-493.79), and the mean duration of a single PS was 2.69 milliseconds (95% confidence interval: 0.95-4.59).ConclusionBased on our findings, spinal manipulative therapy practitioners should expect multiple PSs that most often occur on the upside or the downside facet articulations when performing HVLA thrust manipulation to the lumbosacral junction (ie, L5-S1). However, whether the multiple PSs found in this study emanated from the same joint or adjacent ipsilateral or contralateral facet joints remains unknown. A single model may not necessarily be able to explain all of the audible sounds during HVLA thrust manipulation.  相似文献   
973.
Boiling histotripsy (BH) is an experimental focused ultrasound technique that produces non-thermal mechanical ablation. We evaluated the feasibility, short-term histologic effects and the resulting acute inflammatory response to BH ablation of renal cell carcinoma (RCC) in the Eker rat. Genotyped Eker rats were monitored for de novo RCCs with serial ultrasound (US) imaging. When tumors were ≥8 mm, rats underwent ultrasound-guided extracorporeal ablation of the tumor with BH, a pulsed focused US technique that produces non-thermal mechanical ablation of targeted tissues, or a sham US procedure. Treatments targeted approximately 50% of the largest RCC with a margin of normal kidney. BH treated rats were euthanized at 1 (n?=?4) or 48 (n?=?4) h, and sham patients (n?=?4) at 48 h. Circulating plasma cytokine levels were assessed with multiplex assays before and at 0.25, 1, 4, 24 and 48 h following treatment. Kidneys were collected and processed for histologic assessment, immunohistochemistry and intrarenal cytokine concentration measurements. For statistical analysis Student's t-test was used. US-guided BH treatment was successful in all animals, producing hypoechoic regions within the targeted volume consistent with BH treatment effect. Grossly, regions of homogenized tissue were apparent with evidence of focal intra-parenchymal hemorrhage. Histologically, BH produced a sharply demarcated region of homogenized tumor and non-tumor tissue containing acellular debris. BH treatment was associated with significantly increased relative concentration of plasma TNF versus sham treatment (p < 0.05) and transient elevations in high-mobility group box 1 (HMGB1), IL-10 and IL-6 consistent with acute inflammatory response to trauma. Intrarenal cytokine concentrations followed the same trend. At 48 h, enhanced infiltration of CD8+ T cells was observed by immunohistochemistry in both the treated and un-treated contralateral RCC/kidneys in BH-treated animals versus sham treatment. BH treatment was well tolerated with transient gross hematuria and a perinephric hematoma developing in one subject each. The study demonstrates the feasibility of BH ablation of de novo RCC and suggests activation of the acute inflammatory cascade following treatment that appears to stimulate CD8+ T cell infiltration of both treated and untreated tumors. Longer duration chronic studies are ongoing to characterize the longevity and robustness of this response.  相似文献   
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We conducted Mongolia's first nation-wide cross-sectional survey of sexually transmitted infections (STIs) among pregnant women attending prenatal care. Among our 2000 participants, 386 (19.3%) were infected with Chlamydia trachomatis, 133 (6.7%) with Trichomonas vaginalis, 121 (6.1%) with Neisseria gonorrhoeae, and 128 (6.4%) were seropositive for Treponemal antibodies. None of our participants were seropositive for HIV infection. Additionally, 605 (30.3%) of the women had at least one STI, 133 (6.7%) had a double infection, and 15 (0.8%) had a triple infection. Our results suggest that STIs are a serious problem in Mongolia. Pregnant women represent a lower-risk general population; these high STI rates suggest that at this nascent stage, the identification, treatment, and prevention of STIs as risk factors for HIV transmission are crucial in the prevention of the emerging Mongolian HIV epidemic.  相似文献   
980.
BACKGROUND/AIMS: The aim of this study was to evaluate long term safety and antiviral activity of different doses of emtricitabine given once daily to patients chronically infected with hepatitis B. METHODS: Eligible patients were randomized in a double-blind, parallel study to evaluate 25, 100 or 200 mg once daily doses of emtricitabine for 48 weeks. Patients were then followed for an additional 48 weeks on open-label 200 mg emtricitabine. Serum HBV DNA, ALT, and hepatitis B serology were measured at regular intervals over the 2 years. Resistance surveillance was performed after 1 and 2 years on viremic samples, i.e. > 4700 copies/mL. RESULTS: Emtricitabine was well tolerated and produced a dose proportional antiviral response. After 2 years, 53% of the patients had serum HBV DNA < or = 4700 copies/mL, 33% seroconverted to anti-HBe and 85% had normal ALT. Eighteen percent of the patients who had received 200 mg emtricitabine for 2 years developed resistance mutations. CONCLUSIONS: Emtricitabine was well tolerated and demonstrated a potent antiviral response for up to 2 years in patients with chronic hepatitis B infection. Based on these data, 200 mg emtricitabine once daily was chosen as the optimal dose for future hepatitis B studies.  相似文献   
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