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991.
Lone Tjellesen Anders Gotfredsen Jens Borg Claus Christiansen 《Clinical physiology and functional imaging》1983,3(4):359-364
Summary. Total body bone mineral (TBBM), measured by dual photon absorptiometry, and local body bone mineral content (BMC), measured by single photon absorptiometry, in both forearms were determined in 49 epileptic patients, 19 receiving phenytoin and 30 receiving carbamazepine, and in 55 controls. A highly significant correlation was found between BMC and TBBM in the patients (r = 0·81, SEE = 10·6%), as well as in the controls(r = 0·78, SEE = 9·9%). Furthermore, the intercepts and the slopes were virtually of the same order. The patients on phenytoin had a mild generalised osteomalacia, independent of method used, whereas the patients on carbamazepine did not have this side-effect. It is concluded that BMC of the forearm can be used as a valid estimate of total body bone mineral in groups of epileptic patients and in normal subjects. 相似文献
992.
Vertebral Fractures After Discontinuation of Denosumab: A Post Hoc Analysis of the Randomized Placebo‐Controlled FREEDOM Trial and Its Extension 下载免费PDF全文
Steven R Cummings Serge Ferrari Richard Eastell Nigel Gilchrist Jens‐Erik Beck Jensen Michael McClung Christian Roux Ove Törring Ivo Valter Andrea T Wang Jacques P Brown 《Journal of bone and mineral research》2018,33(2):190-198
Denosumab reduces bone resorption and vertebral and nonvertebral fracture risk. Denosumab discontinuation increases bone turnover markers 3 months after a scheduled dose is omitted, reaching above‐baseline levels by 6 months, and decreases bone mineral density (BMD) to baseline levels by 12 months. We analyzed the risk of new or worsening vertebral fractures, especially multiple vertebral fractures, in participants who discontinued denosumab during the FREEDOM study or its Extension. Participants received ≥2 doses of denosumab or placebo Q6M, discontinued treatment, and stayed in the study ≥7 months after the last dose. Of 1001 participants who discontinued denosumab during FREEDOM or Extension, the vertebral fracture rate increased from 1.2 per 100 participant‐years during the on‐treatment period to 7.1, similar to participants who received and then discontinued placebo (n = 470; 8.5 per 100 participant‐years). Among participants with ≥1 off‐treatment vertebral fracture, the proportion with multiple (>1) was larger among those who discontinued denosumab (60.7%) than placebo (38.7%; p = 0.049), corresponding to a 3.4% and 2.2% risk of multiple vertebral fractures, respectively. The odds (95% confidence interval) of developing multiple vertebral fractures after stopping denosumab were 3.9 (2.1–7. 2) times higher in those with prior vertebral fractures, sustained before or during treatment, than those without, and 1.6 (1.3–1.9) times higher with each additional year of off‐treatment follow‐up; among participants with available off‐treatment total hip (TH) BMD measurements, the odds were 1.2 (1.1–1.3) times higher per 1% annualized TH BMD loss. The rates (per 100 participant‐years) of nonvertebral fractures during the off‐treatment period were similar (2.8, denosumab; 3.8, placebo). The vertebral fracture rate increased upon denosumab discontinuation to the level observed in untreated participants. A majority of participants who sustained a vertebral fracture after discontinuing denosumab had multiple vertebral fractures, with greatest risk in participants with a prior vertebral fracture. Therefore, patients who discontinue denosumab should rapidly transition to an alternative antiresorptive treatment. Clinicaltrails.gov : NCT00089791 (FREEDOM) and NCT00523341 (Extension). © 2017 American Society for Bone and Mineral Research. 相似文献
993.
Gieffers J Rupp J Gebert A Solbach W Klinger M 《Antimicrobial agents and chemotherapy》2004,48(4):1402-1405
Persistent growth forms of Chlamydia pneumoniae have been associated with chronic infections in vivo. We investigated the effects of first-line therapeutics on the induction of persistence by monitoring recoverable organisms, gene expression of membrane proteins, and morphology. We found that all of the antibiotics tested have distinct and subinhibitory concentrations at which they induce persistence. 相似文献
994.
995.
Schrezenmeier H Walther-Wenke G Müller TH Weinauer F Younis A Holland-Letz T Geis G Asmus J Bauerfeind U Burkhart J Deitenbeck R Förstemann E Gebauer W Höchsmann B Karakassopoulos A Liebscher UM Sänger W Schmidt M Schunter F Sireis W Seifried E 《Transfusion》2007,47(4):644-652
BACKGROUND: The GERMS Group initiated a prospective multicenter study to assess prevalence and nature of bacterial contamination of pooled buffy-coat platelet concentrates (PPCs) and apheresis platelet concentrates (APCs) by routine screening with a bacterial culture system. STUDY DESIGN AND METHODS: In nine centers overall, 52,243 platelet (PLT) concentrates (15,198 APCs, 37,045 PPCs) were analyzed by aerobic and anaerobic cultures (BacT/ALERT, bioMérieux). RESULTS: In 135 PLT concentrates (PCs; 0.26%), bacteria could be identified in the first culture (0.4% for APCs vs. 0.2% for PPCs; p < 0.001). In 37 (0.07%) of these PC units, the same bacteria strain could be identified in a second culture from the sample bag and/or the PC unit. The rate of confirmed-positive units did not differ significantly between APC (0.09%; 1/1169) and PPC units (0.06%; 1/1544). Bacteria from skin flora (Propionibacterium acnes, Staphylococcus epidermidis) were the most prevalent contaminants. Median times to first positive culture from start of incubation were 0.7 and 3.7 days in aerobic and anaerobic cultures for confirmed-positive units. With a "negative-to-date" issue strategy, most PC units (55%) had already been issued by time of the first positive culture. CONCLUSION: The rate of confirmed bacterial contamination of PC units was low. Nevertheless, clinicians must be aware of this risk. The risk of bacterial contamination does not warrant universal preference of APCs. It must be questioned whether routine bacterial screening by a culture method can sufficiently prevent contaminated products from being transfused due to the delay until a positive signal in the culture system and due to false-negative results. 相似文献
996.
The objective of the study was to assess inter-rater reliability of one palpation and six pain provocation tests for pain of sacroiliac origin. The sacroiliac joint (SIJ) is a potential source of low back and pelvic girdle pain. Diagnosis is made primarily by physical examination using palpation and pain provocation tests. Previous studies on the reliability of such tests have reported inconclusive and conflicting results. Fifty-six women and five men aged 18-50 years old were included in the study. Fifteen patients had ankylosing spondylitis; 30 women had post partum pelvic girdle pain for more than 6 weeks; and 16 people had no low back or pelvic girdle pain. All participants were examined twice on the same day by experienced manual therapists. Percentage agreement and kappa statistic were used to evaluate the tests reliability. Results showed percentage agreement and kappa values ranged from 67% to 97% and 0.43 to 0.84 for the pain provocation tests. For the palpation test the percent agreement was 48% and the kappa value was -0.06. Clusters of pain provocation tests were found to have good percentage agreement, and kappa values ranged from 0.51 to 0.75. In conclusion this study has shown the reliability of the pain provocation tests employed were moderate to good, and for the palpation test, reliability was poor. Clusters out of three and five pain provocation tests were found to be reliable. The cluster of tests should now be validated for assessment of diagnostic power. 相似文献
997.
Adipose tissue blood flow was measured in six healthy, non-obese subjects with the xenon wash-out technique after labelling of the tissue by either injection of 133Xe dissolved in isotonic sodium chloride (water depot) or injection of 133Xe in gas form (gas depot). The wash-out rates were registered from four depots simultaneously. Two depots were placed above the umbilicus, and two depots were placed below the umbilicus in the abdominal, subcutaneous adipose tissue. A water depot and a gas depot were placed in the two positions, respectively. It was not possible to demonstrate any difference between the wash-out rates registered from the two depot types, and it was also not possible to demonstrate any difference between the changes in wash-out rates induced by an oral glucose load. Similarly, the tissue distribution of the water and the gas depots appeared to be similar as registered by a gamma camera. It is concluded that that the two tissue labelling modes give identical results. However, there are significant regional differences in the wash-out rates of xenon from subcutaneous, abdominal adipose tissue, the wash-out rates from infraumbilical depots being about 20% lower than from the supraumbilical depots. 相似文献
998.
Björn Knutsson Sebastian Mukka Jens Wahlström Bengt Järvholm Arkan S. Sayed-Noor 《The spine journal》2018,18(8):1313-1317
Background Context
Tobacco smoking is an injurious habit associated with a number of chronic disorders. Its influence on disc metabolism and degeneration including lumbar spinal stenosis (LSS) has been investigated in the literature.Purpose
We aimed to investigate whether tobacco smoking is an independent risk factor for undergoing surgical intervention for LSS.Study Design/Setting
This is a prospective cohort study.Patient Sample
The patient sample of 331,941 workers was derived from a Swedish nationwide occupational surveillance program for construction workers.Outcome Measure
The outcome measure included the incidence of undergoing surgical intervention for LSS in tobacco smokers versus no smokers.Materials and Methods
At inclusion, age, sex, body mass index (BMI), workers' job title, and self-reported smoking habits were registered. The workers were divided into four categories: never smoked, former smoker, moderate current (1–14 cigarettes/day), and heavy current (≥15 cigarettes/day). Patients who underwent a surgically treated LSS were defined using the relevant International Classification of Diseases (ICD) disease code derived from the Swedish National Patient Register.Results
A total of 331,941 participants were included in the analysis. Forty-four percent of the participants were non-smokers, 16% were former smokers, 26% were moderate smokers, and 14% were heavy smokers. The vast majority of construction workers were males (95%). During the average follow-up of 30.7 years, 1,623 participants were surgically treated for LSS. The incidence rate ratio (IRRs) of LSS varied across smoking categories, with the highest values found in heavy smokers. Compared with non-smokers, all smoking categories show an increased incidence of surgically treated LSS. The findings were consistent even when the comparison was performed for participants with BMIs between 18.5 and 25 and for participants aged between 40 and 74 years.Conclusions
Tobacco smoking is associated with an increased incidence of surgically treated LSS. The effect seems to be dose related, whereby heavy smokers have a higher risk than moderate or former smokers. 相似文献999.
Nombela-Arrieta C Mempel TR Soriano SF Mazo I Wymann MP Hirsch E Martínez-A C Fukui Y von Andrian UH Stein JV 《The Journal of experimental medicine》2007,204(3):497-510
Recent observations using multiphoton intravital microscopy (MP-IVM) have uncovered an unexpectedly high lymphocyte motility within peripheral lymph nodes (PLNs). Lymphocyte-expressed intracellular signaling molecules governing interstitial movement remain largely unknown. Here, we used MP-IVM of murine PLNs to examine interstitial motility of lymphocytes lacking the Rac guanine exchange factor DOCK2 and phosphoinositide-3-kinase (PI3K)gamma, signaling molecules that act downstream of G protein-coupled receptors, including chemokine receptors (CKRs). T and B cells lacking DOCK2 alone or DOCK2 and PI3Kgamma displayed markedly reduced motility inside T cell area and B cell follicle, respectively. Lack of PI3Kgamma alone had no effect on migration velocity but resulted in increased turning angles of T cells. As lymphocyte egress from PLNs requires the sphingosine-1-phosphate (S1P) receptor 1, a G(alphai) protein-coupled receptor similar to CKR, we further analyzed whether DOCK2 and PI3Kgamma contributed to S1P-triggered signaling events. S1P-induced cell migration was significantly reduced in T and B cells lacking DOCK2, whereas T cell-expressed PI3Kgamma contributed to F-actin polymerization and protein kinase B phosphorylation but not migration. These findings correlated with delayed lymphocyte egress from PLNs in the absence of DOCK2 but not PI3Kgamma, and a markedly reduced cell motility of DOCK2-deficient T cells in close proximity to efferent lymphatic vessels. In summary, our data support a central role for DOCK2, and to a lesser extent T cell-expressed PI3Kgamma, for signal transduction during interstitial lymphocyte migration and S1P-mediated egress. 相似文献
1000.
Cozzi-Lepri A Ruiz L Loveday C Phillips AN Clotet B Reiss P Ledergerber B Holkmann C Staszewski S Lundgren JD;EuroSIDA Study Group 《Antiviral therapy》2005,10(7):791-802
BACKGROUND: Studies have suggested that HIV-1 may develop thymidine analogue mutations (TAMs) by one of two distinct pathways - the TAM1 pathway (including mutations 41L, 210W and 215Y) or the TAM2 pathway (including mutations 67N, 70R and 219E/Q) - under the pressure of a not fully suppressive thymidine-analogue-containing regimen. METHODS: Frozen plasma samples stored in the EuroSIDA repository were selected and sent to two central laboratories for genotypic analysis. We considered 733 patients with at least one genotypic test showing > or =1 TAMs (the first of these tests in chronological order was used). TAM1 and TAM2 genotypic profiles were defined in accordance with previous literature. Statistical modelling involved logistic regression and linear regression analysis for censored data. RESULTS: The observed frequencies of patterns classifiable as TAM1 or TAM2 profiles were markedly higher than the probabilities of falling into these classifications by chance alone. The chance of detecting a TAM2 profile increased by 25% per additional year of exposure to zidovudine. We found that mutations 67N and 184V were not associated with a particular TAM profile. In the presence of TAM2 profiles, the adjusted mean difference in the 6-month viral reduction was 0.96 log10 copies/ml (95% confidence interval: 0.20; 1.73) higher in patients who started stavudine-containing regimens instead of zidovudine-containing regimens. CONCLUSIONS: This study provides evidence that the suggested TAM clustering is a real phenomenon and that it may be driven by which thymidine analogue the patients has used. In patients with TAM2-resistant viruses, stavudine appears to retain greater viral activity than zidovudine. 相似文献