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Endothelial injury is a characteristic finding in chronic kidney disease and is associated with both markedly increased cardiovascular risk and chronic kidney disease progression. The past decade has seen a remarkable surge of interest in the role of bone marrow-derived cells for the protection, repair, and regeneration of injured endothelium. In particular, despite controversies regarding their mechanisms of action, endothelial progenitor cells have garnered considerable attention, with multiple reports suggesting that these cells exhibit remarkable pro-angiogenic effects. Recent advances in our understanding of how the bone marrow responds to endothelial injury now suggest that multiple bone marrow cell populations, including both endothelial progenitor cells and a novel group of cells called early outgrowth cells, promote endothelial repair and regeneration through different, yet complementary, mechanisms. Moreover, certain subsets of bone marrow-derived cells also appear to have novel, potent, angiogenesis-independent tissue-protective properties. The bone marrow should thus now be viewed not only as a hematopoiesis organ, but also as a rich reservoir of cells capable of protecting and even regenerating nonhematopoietic tissues such as the kidney. To harness the prognostic and therapeutic potential of the bone marrow, the renal community must be aware of recent advances in our understanding of the nature and therapeutic potential of these cells. 相似文献
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STUDY DESIGN.: A retrieval analysis of wear modes and fixation of lumbar total disc replacements (TDRs). Explanted Prodisc-L TDRs were prospectively collected during a 7-year period (2005-2011) and analyzed. OBJECTIVE.: To assess the in vivo modes of wear and fixation of lumbar TDR with the Prodisc-L device. SUMMARY OF BACKGROUND DATA.: Inferior clinical outcomes and failure of lumbar TDR may occur because of suboptimal component fixation, wear properties, and impingement in a subset of patients. Posterior component TDR impingement has been demonstrated radiographically; however, despite its widespread use, the in vivo mechanical performance and fixation of the Prodisc-L device remain unknown. METHODS.: Explanted polyethylene and metallic (CoCrMo) components of Prodisc-L devices were examined by light stereo-microscopy (6X-31X), scanning electron microscopy, and energy-dispersive x-ray analysis from an international retrieval registry, with 13 participating surgeons. RESULTS.: Nineteen ProDisc-L devices from 18 patients (age, 44.7 ± 2.9 yr) following an index TDR at L4-L5 (n = 6), L5-S1 (n = 11), and unknown level (n = 2) were explanted for pain (n = 8), prosthesis subluxation/migration (n = 4), end plate collapse/subsidence (n = 3), polyethylene dislodgement (n = 3), and unknown (n = 2) after a mean length of implantation of 13.0 ± 3.9 months. Surface area of bony ongrowth was 9.6 ± 2.9% (range, 0%-52.5%). TDR burnishing was observed posteriorly consistent with component impingement in extension in 53% (8/15) (P < 0.02), more commonly than anterior 20% (3/15) lateral 20% (n = 3) (3/15) patterns. Circumferential burnishing was not observed. Posterior impingement was associated with 6° lordotic implants (P < 0.05) and 10-mm polyethylene size (P < 0.05). Backside wear occurred in 75% (9 of 12) of the disassembled implants and third-body wear was observed in 33% (5 of 15). CONCLUSION.: Metallic end plate burnishing was evident in a large percentage of clinically failed Prodisc-L TDR devices, most commonly posteriorly, consistent with impingement in extension. Long-term follow-up studies will evaluate the effects of the observed backside wear, third-body wear, and end plate impingement on clinical outcomes. 相似文献
995.
Background
Tumor recurrence after resection of hepatocellular carcinoma is a common phenomenon. Re-resection and radiofrequency ablation (RFA) are good options for treating recurrent HCC. This study compared the efficacy of these two modalities in the treatment of intrahepatic HCC recurrence after hepatectomy. 相似文献996.
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Shirley Poon Anna Pupco Gideon Koren Pina Bozzo 《Canadian family physician Médecin de famille canadien》2014,60(7):631-632
Question
I have a patient recently confirmed to be 6 weeks pregnant. For the past 6 months she has been treated for an opioid addiction with buprenorphine-naloxone combination. Should I be concerned about her exposure to this drug combination up to this point of the pregnancy? Should I switch her medication to methadone now that she is pregnant?Answer
The limited data on buprenorphine exposure during pregnancy show no increased risk of adverse outcomes in the newborn. There are limited data on naloxone exposure during pregnancy; however, oral use is not expected to be associated with an increased risk of adverse pregnancy outcomes. Physicians treating pregnant women or women who become pregnant while they are stable taking buprenorphine-naloxone treatment are advised to continue this treatment but to consider transition to buprenorphine monotherapy.There are limited prevalence data on substance abuse in pregnant women in Canada. In the United States there has been an increase in the prevalence of substance abuse among women, and up to 90% of women who abuse substances are of reproductive age.1 Further, the proportion of pregnancies that are unintended among opioid-dependent women ranges between 80% and 90%.2 This makes opioid use and dependence in pregnancy an important health problem. While little information exists about the incidence of treatment of opioid addiction in pregnant women, more than 550 000 women were admitted to US treatment programs in 2007, with roughly 4% being pregnant at the time of admission. In 8.6% of these pregnant women, opioids were the primary substance of abuse at admission.3Although it would be ideal to abstain from taking opioids throughout the course of pregnancy, most opioid-dependent women are unable to do so even under close medical supervision and are at risk of relapse. The pressure from rapid detoxification might cause maternal stress, withdrawal, and fetal stress, which are associated with poor fetal growth, preterm delivery, and fetal death.4 Abrupt opioid withdrawal in pregnancy might also increase the likelihood of abortion, premature labour, miscarriage, and stillbirth.5 The current criterion standard for managing opioid dependence in pregnant women is methadone maintenance.6 相似文献999.
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Alexander Aarvold James O. Smith Edward R. Tayton Caroline J. Edwards Darren J. Fowler Edward D. Gent Richard O. C. Oreffo 《Journal of children's orthopaedics》2012,6(4):339-346