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Bone density is a key parameter in determining the surgical procedure of implant placement and for the predictability of successful implant treatment. Several clinical studies have shown lower survival rates of implants in maxilla which was attributed to poor bone quality. The present study compared the variations in the pre-operative and post-operative bone density values in Hounsfield units using CT between drilling technique and bone expansion technique at 0.25 and 1.0 mm sections at two sites which were selected in maxillary arch between the second premolar regions of either quadrants and results have shown bone expansion technique is superior to drilling technique in division III bone.  相似文献   
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Purpose

Venous thromboembolism (VTE), including deep venous thrombosis (DVT) and pulmonary embolism, is a common cause of morbidity and mortality after radical cystectomy. The purpose of our study was to evaluate the utility of extended outpatient chemoprophylaxis against VTE after radical cystectomy—with a focus on any reduction in the incidence of VTE, including DVT and pulmonary embolism.

Materials and methods

Beginning in April 2013, we prospectively instituted a policy of extending inpatient VTE prophylaxis with subcutaneous heparin/enoxaparin for 30 days postoperatively. For this study, we reviewed the electronic medical records of all patients who underwent radical cystectomy at our institution from January 2012 through December 2015. The experimental group (n = 79) received extended outpatient chemoprophylaxis against VTE; the control group (n = 51) received no chemoprophylaxis after discharge. The primary outcome was the 90-day incidence of VTE. The secondary outcomes included the overall complication rate, the hemorrhagic complication rate, as well as the rate of readmission within 30 days of hospital discharge.

Results

The experimental group experienced a significantly lower rate of DVT (5.06%), assessed as of 90 days postoperatively, than the control group (17.6%): a relative risk reduction of 71.3% (P = 0.021). We found no significant differences in secondary outcomes between the 2 groups, including the overall complication rate (54.4% vs. 68.6%), the hemorrhagic complication rate (3.7% vs. 2.0%), and the readmission rate (21.5% vs. 29.4%).

Conclusion

Extended outpatient chemoprophylaxis significantly reduced the incidence of VTE.  相似文献   
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Background

Adductor canal block (ACB) is a peripheral nerve blockade technique that provides good pain control in patients undergoing total knee arthroplasty which however does not relieve posterior knee pain. The recent technique of an ultrasound-guided local anesthetic infiltration of the interspace between popliteal artery and the capsule of posterior knee (IPACK) has shown promising results in providing significant posterior knee analgesia without affecting the motor nerves.

Materials and methods

A prospective study was conducted from September 2016 to March 2017 in a total of 120 patients undergoing unilateral total knee arthroplasty. The initial 60 consecutive patients received ACB?+?IPACK (Group 1, n?=?60), and the subsequent 60 patients received ACB alone (Group 2, n?=?60). All patients were evaluated with VAS score for pain recorded at 8 h, postoperative day (POD) 1 and POD 2 after the surgery. The secondary outcome measures assessed were the range of movement (ROM) and ambulation distance.

Results

VAS score showed significantly (p?<?0.005) better values in ACB?+?IPACK group compared to the ACB group. The mean ROM of knee and ambulation distance also showed significantly better values in ACB?+?IPACK group compared to the ACB group.

Conclusion

ACB?+?IPACK is a promising technique that offers improved pain management in the immediate postoperative period without affecting the motor function around the knee joint resulting in better ROM and ambulation compared to ACB alone.
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The optimal viral load threshold at which to initiate preemptive cytomegalovirus (CMV) therapy in hematopoietic cell transplantation (HCT) recipients remains to be defined. In an effort to address this question, we conducted a retrospective study of 174 allogeneic HCT recipients who underwent transplantation at a single center between August 2012 and April 2016. During this period, preemptive therapy was initiated at the discretion of the treating clinician. A total of 109 patients (63%) developed CMV viremia. The median time to reactivation was 17 days (interquartile range, IQR, 7-30 days) post-HCT. A peak viremia ≥150?IU/mL was strongly associated with a reduced probability of spontaneous clearance (relative risk, .16; 95% confidence interval, .1-.27), independent of established clinical risk factors, including CMV donor serostatus, exposure to antithymocyte globulin, and underlying lymphoid malignancy. The median time to clearance of viremia was significantly shorter in those who started therapy at CMV <350?IU/mL (19 days; IQR, 11-35 days) compared with those who started antiviral therapy at higher viremia thresholds (33 days; IQR, 21-42 days; P?=?.02). The occurrence of treatment-associated cytopenias was frequent but similar in patients who started preemptive therapy at CMV <350?IU/mL and those who started at CMV >350?IU/mL (44% versus 57%; P?=?.42). Unresolved CMV viremia by treatment day 35 was associated with increased risk of therapeutic failure (32% versus 0%; P?=?.001). Achieving eradication of CMV viremia by treatment day 35 was associated with a 74% reduction in 1-year nonrelapse mortality (NRM) (adjusted hazard ratio [HR], .26; 95% confidence interval [CI], .1-.8; P?=?.02), whereas therapeutic failure was associated with a significant increase in the probability of 1-year NRM (adjusted HR, 26; 95% CI, 8-87; P?<.0001). We conclude that among allogeneic HCT patients, a peak CMV viremia ≥150?IU/mL is associated with a >80% reduction in the probability of spontaneous clearance independent of ATG administration, CMV donor serostatus, and lymphoid malignancy, and is a reasonable cutoff for preemptive therapy. Delaying initiation of therapy until a CMV value ≥350?IU/mL is associated with more protracted CMV viremia, and unresolved viremia by treatment day 35 is associated with a significant increase in NRM.  相似文献   
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