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Cardiac resynchronization therapy is an effective tool for the treatment of drug-refractory heart failure in patients with left ventricular dysfunction and inter/intra ventricular conduction delay. Supraventricular tachycardias may prevent effect delivery of this therapy. We report three cases in which effective therapy was limited by asymptomatic supraventricular tachycardia. Diagnostic pacing maneuvers were performed via the implanted device to determine the underlying arrhythmia mechanism. These cases highlight the importance of (1) treating supraventricular tachycardias before and after implantation of cardiac devices and (2) using device based programmed stimulation to diagnose the mechanism of supraventricular tachycardias. Dr. Gerstenfeld is supported by a Scientist Development Grant from the American Heart Association.  相似文献   
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Background

The hypocellular variant of acute myeloid leukemia accounts for less than 10% of all cases of adult acute myeloid leukemia. It is defined by having less than 20 percent of cellular bone marrow in a biopsy at presentation. It is unclear in the literature whether the outcome of hypocellular acute myeloid leukemia differs from that of non-hypocellular acute myeloid leukemia.

Design and Methods

We retrospectively analyzed all the cases reported to be hypocellular acute myeloid leukemia between 2000 and 2009. A second pathology review was conducted and the diagnosis was confirmed in all cases.

Results

One hundred twenty-three (9%) patients were identified: patients with hypocellular acute myeloid leukemia were older than those with non-hypocellular acute myeloid leukemia (P=0.009) and more frequently presented with cytopenias (P<0.001). Forty-one patients with hypocellular acute myeloid leukemia had an antecedent hematologic disorder and 11 patients had received prior chemo-radiotherapy for non-hematopoietic neoplasms. On multivariate analysis, overall survival, remission duration and event-free survival were comparable to those of other patients with acute myeloid leukemia.

Conclusions

The outcome of hypocellular acute myeloid leukemia does not differ from that of non-hypocellular acute myeloid leukemia.  相似文献   
24.
Background: Implant therapy is a highly predictable treatment option; however, insufficient data exist to show whether flapless implant surgery provides better esthetic outcomes and less bone loss than implant surgery with a flap approach. Methods: In this randomized, controlled study comparing the flapless and traditional flap protocol for implant placement, 24 patients received a single implant in the anterior maxillary region. A cone beam computed tomography–aided surgical guide was used for implant placement surgery for both groups. Implants were restored using a one‐piece, screw‐retained ceramic crown at 3 months. Radiographic and clinical measurements were assessed at baseline (implant placement) and at 3 (crown placement), 6, 9, and 15 months. Clinical parameters evaluated were plaque index, gingival index, papillary index (PPI) (0 = no papilla, 1 = less than half, 2 = more than half but not complete, 3 = complete fill, and 4 = overfill), marginal tissue levels, biotype, width of keratinized tissue, and soft tissue thickness. Results: Implant success rate was 92% in both groups. Mean PPI values for the flap control group and flapless test group were 2.38 ± 0.51 versus 2.31 ± 0.48 at crown placement (P = 0.68) and 2.52 ± 0.52 versus 2.64 ± 0.54 at 15 months (P = 0.42), respectively. PPI increased over time in both groups, although the flapless group had a significantly larger change in PPI from crown placement to 6 and 9 months (P <0.01). Crestal bone levels in the flap group were more apical in relation to the implant platform than those in the flapless group for the duration of the study. No differences among groups were noted for all other measurements. Conclusions: Both flapless and flap implant placement protocols resulted in high success rates. A flapless protocol may provide a better short‐term esthetic result, although there appears to be no long‐term advantage.  相似文献   
25.
Polycystic ovary syndrome (PCOS) is characterized by insulin resistance. Chronic low grade inflammation has been reported to participate in the pathogenesis of insulin resistance. Chitotriosidase (ChT), a protein secreted by activated macrophages, has been shown to be involved in chronic inflammatory responses. In the present study, serum chitotriosidase activity and its relationship with insulin resistance were determined in patients with PCOS.34 patients with PCOS and 44 age and body mass index (BMI) matched healthy controls were enrolled in the study. ChT activity was measured by the fluorescence method. High sensitivity C reactive protein (hs-CRP) and adiponectin levels were determined by enzyme immunoassay (EIA). Insulin resistance was calculated by the homeostasis model assessment of insulin resistance (HOMA-IR) formula.Plasma ChT activity, hs-CRP level and HOMA-IR score were significantly higher (p=0.024, p=0.002, p=0.001, respectively) while plasma adiponectin concentration was significantly lower (p=0.018) in women with PCOS compared to healthy controls. Blood ChT activity correlated positively with age, waist-to-hip ratio (WHR), BMI, hs-CRP, HOMA-IR and negatively with blood adiponectin level. After adjustment for age and BMI, ChT activity, total testosterone level and WHR remained as the independent predictors of HOMA-IR score in logistic regression analysis.ChT activity is increased in patients with PCOS in concordance with insulin resistance. These findings may reflect the pronounced risk for metabolic syndrome and atherosclerotic diseases in this particular patient group.  相似文献   
26.
Vein of Marshall Ethanol in Recurrent AF. Introduction: Atrial fibrillation (AF) or flutter can recur after pulmonary vein (PV) antral isolation (PVAI). The vein of Marshall (VOM) has been linked to the genesis of AF. We hypothesized that the VOM may play a role in AF recurrences and that VOM ethanol infusion may have therapeutic value in this setting. Methods and Results: Sixty-one patients with recurrent AF or flutter after PVAI were studied. The VOM was successfully cannulated in 54; VOM and PV electrograms were recorded, and differential PV-VOM pacing was performed. VOM signals were present in all patients; however, VOM triggers of AF could not be demonstrated. VOM tachycardia was present in 1 patient. Left inferior (LIPV) and left superior (LSPV) reconnection was present in 32 and 30 patients, respectively. Differential pacing in VOM and LIPV showed VOM-mediated LIPV reconnection in 5/32 patients. In others, VOM and PV connected indirectly via left atrial tissues. Up to four 1 cc infusions of 98% ethanol were delivered in the VOM. Regardless of the reconnection pattern, ethanol infusion eliminated LIPV and LSPV reconnection in 23/32 and 13/30 patients, respectively. Ethanol terminated VOM and LIPV tachycardias in 2 patients. There were no acute procedural complications. Conclusions: VOM signals are consistently present in recurrent AF. VOM may rarely play a role in PV reconnection. However, VOM ethanol infusion can be useful in patients with recurrent AF after PVAI, assisting in achieving redisconnection of reconnected left PVs.  相似文献   
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Renal transplant is usually performed at the end stage of renal disease. Most of the transplant recipients become susceptible to infections due to chronic uremia, protein depletion, anemia and administration of immunosuppressive drugs. It is a retrospective study of 510 post renal transplant recipients. 378 (74%) renal transplant recipients suffered from the infections. Most common site of infection was urinary tract infection (53%). Out of 26% of wound infections, the deep wound infection (23%) was six times higher than superficial wound infection (3.5%). Chest infection and bacteraemia were noticed to be 18% and 8%, respectively. The common isolate was Escherichia coli (160) followed by Staphylococcus aureus (140), Enterococcus (86) and Pseudomonas (69).  相似文献   
30.
To compare the clinical presentation and outcomes of retinoblastoma (RB) based on age at presentation. Retrospective comparative study of 1940 eyes of 1450 children with RB. Presentation of RB with enlarged eyeball and eyelid swelling (2% and < 1% in ≤ 1 year, 4% and 2% in > 1–2 years, 7% and 2% in > 2–3 years, and 12% and 4% in > 3 years; p < 0.0001 and p = 0.05, respectively) is more common with increasing age. Based on the 8th edition of American Joint Committee Classification, T1 is more common in children younger than 1 year (27%), while T4 is more common in children > 3 years of age (20%) (p < 0.0001). Kaplan–Meier (KM) estimate at 1 and 5 years for globe salvage was 64% and 58% in children ≤ 1 year of age versus 30% and 20% in children > 3 years, respectively [Hazard ratio (HR) = 2.48; p < 0.0001], and KM estimate at 1 and 5 years for life salvage was 99% and 97% in children ≤ 1 year of age versus 89% and 78% in children older than 3 years, respectively (HR = 7.65; p < 0.0001). Uncommon clinical features of RB including enlarged eyeball and eyelid swelling are more common with increasing age. Younger age at presentation with RB is associated with better prognosis including higher chances of life and globe salvage.  相似文献   
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