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61.
62.

Background

Very little is known about possible association of nevi and melasma. The study objective was to determine if there is an association between melasma and existence of different kinds of nevi.

Methods

In a case-control study, 120 female melasma patients referred to dermatology clinic of Ardabil and 120 patients referred to other specialty clinics who lacked melasma were enrolled after matching for age. Number of different types of nevi including lentigines and melanocytic nevi were compared between case and control group patients. Data were entered into the computer and analyzed by SPSS 13 statistical software.

Results

Mean number of lentigines was 25.5 in melasma group compared to 8 in control group(P < 0.01). Mean number of melanocytic nevi was 13.2 in cases compared to 2.8 in control group(P < 0.001). Multivariate analysis showed that existence of freckles, lentigines and more than three melanocytic nevi were positively related to developing melasma. The chance of melasma increased up to 23 times for patients having more than three melanocytic nevi. Congenital nevi were observed among 10% both in case and control groups. Campbell de morgan angiomas were seen among 26 patients(21.8%) in case group compared to 6 patients(5%) in control group.

Conclusion

Existence of lentigines and melanocytic nevi increases chance of having melasma  相似文献   
63.
AIM: To assess the distribution of human leukocyte antigen (HLA)-DQ2 and -DQ8 in Iranian celiac disease (CD) patients and compare them to healthy Iranian controls.METHODS: To predict the HLA-DQA1 and -DQB1 genes, we used six previously reported HLA-tagging single nucleotide polymorphism to determine HLA genotypes in 59 Iranian patients with ‘biopsy-confirmed’ CD and in 151 healthy Iranian individuals. To test the transferability of the method, 50 cases and controls were also typed using a commercial kit that identifies individual carriers of DQ2, DQ7 and DQ8 alleles.RESULTS: In this pilot study 97% of CD cases (n = 57) and 58% of controls (n = 87) were carriers of HLA-DQ2 and/or HLA-DQ8 heterodimers, either in the homozygous or heterozygous state. The HLA-DQ pattern of these 57 CD patients: heterozygous DQ2.2 (n = 14) and homozygous DQ2.2 (n = 1), heterozygous DQ2.5 (n = 33) and homozygous DQ2.5 (n = 8), heterozygous DQ8 (n = 13) and homozygous DQ8 (n = 2). Two CD patients were negative for both DQ2 and DQ8 (3%).CONCLUSION: The prevalence of DQ8 in our CD population was higher than that reported in other populations (25.4%). As reported in other populations, our results underline the primary importance of HLA-DQ alleles in the Iranian population’s susceptibility to CD.  相似文献   
64.
The success of dental implants depends on their placement in bone of adequate density and volume in order to achieve primary stability. Optimal esthetics of implants requires their placement in a position approximating that of the natural teeth they replace. However, there is generally at least some degree of atrophy in the sites where implants are to be placed. This atrophy may occur either before or after tooth extraction. Following extraction of teeth, there is commonly alveolar ridge resorption in horizontal and vertical dimensions. Alternatively, some of the oral hard and soft tissues may be destroyed by pathologic conditions such as periodontitis, endodontic infections, or trauma. All of these conditions may potentially compromise the final esthetics and function of implant-supported restorations. During the initial years of the development of the osseointegration protocol, implants were placed with little or no modification of implant sites. Though osseointegration was successfully achieved, esthetic outcome was not a primary objective of therapy at that time. A gradual paradigm shift has occurred in implant dentistry from merely achieving successful osseointegration to achieving final restorative outcomes that mimic natural dentition and their surrounding oral tissues. These objectives have been materialized by advancements in surgical techniques, as well as availability of biomaterials to enable predictable regeneration of oral hard and soft tissues. The objective of the present review is to briefly discuss some of the techniques that are currently available for implant site development.  相似文献   
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The goal of this prospective study of the piezoelectric pulse sensor device was to determine its technical applications and its ability to detect lower extremity occlusive arterial disease. Ten extremities (five volunteers) were evaluated to assess the ability to place the sensor in the correct anatomic position on a foot without a palpable pulse during cuff occlusion so that pulsatile flow would be detected following cuff deflation; its sensitivity as an end-point detector for pulsatile perfusion; and whether there is a linear qualitative pulse wave response with increasing perfusion pressures. Forty extremities (20 patients) with suspected occlusive arterial disease were studied to evaluate its capability of detecting perfusion as compared with the presence of a palpable pulse, an audible Doppler signal, and a foot volume waveform. The placement of the sensor on 10 normal limbs with temporary arterial occlusion resulted in a recordable waveform following cuff deflation in 100% of the dorsalis pedis arteries and in 10% of the posterior tibial arteries. The piezoelectric pulse sensor was as sensitive for detecting pulsatile perfusion as an audible Doppler signal and demonstrated a linear change in the waveform's amplitude and shape with incremental changes in perfusion pressure. In the 40-extremities with ankle/brachial indices ranging from 0.00 to 1.35, there was uniform agreement between pulse volume and Pulse Check waveforms. The piezoelectric pulse sensor is a sensitive method for monitoring lower extremity arterial perfusion when supplied by the dorsalis pedis artery; however, it is inadequate for the posterior tibial artery. This may be useful in monitoring revascularization procedures in the immediate postoperative period or monitoring the hemodynamic effectiveness of thrombolytic therapy.  相似文献   
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69.

Objective

The purpose of this study was to evaluate the trends in procedure volume, clinical sites of care, and Medicare expenditure for peripheral vascular interventions (PVIs) for lower extremity occlusive disease since the Centers for Medicare and Medicaid Services instituted reimbursement policy changes that broadened payment for procedures performed in physician-owned office-based laboratories (OBLs).

Methods

We analyzed fee-for-service Medicare claims data from 2011 to 2014 to obtain the frequency of use of PVI by type, care setting, and physician specialty. We also assessed changes in the total Medicare cost for PVI by setting.

Results

There was a 60% increase in atherectomy cases among Medicare beneficiaries between 2011 and 2014. During the same period, OBLs experienced a 298% increase in atherectomy volume vs a 27% increase in hospital outpatient settings and an 11% decrease for inpatient hospital settings. In 2014, OBLs were the most common setting for atherectomy. Nonatherectomy PVIs grew more modestly at just 3% but also experienced site of care shifts. Vascular surgeons and cardiologists accounted for the majority of office-based PVIs in 2014. Total Medicare costs for PVIs increased 18% from 2011 to 2014. Hospital inpatient costs declined 1%, whereas costs for hospital outpatient PVIs increased by 41% and physician office costs increased by 258%.

Conclusions

The migration of revascularization procedures for lower extremity peripheral arterial occlusive disease continues from the inpatient to the outpatient setting and especially to OBLs. Increased use of atherectomy in all segments of the lower extremity arterial system has been observed, particularly in OBLs, without substantial evidence in the literature of increased efficacy compared with standard angioplasty with or without stenting. Generous Medicare reimbursement for in-office atherectomy procedures is likely contributing to the volume shifts observed.  相似文献   
70.

Background

The traditional treatment for a cT1b renal tumor has been radical nephrectomy. However, recent guidelines have shifted towards partial nephrectomy (PN) in selected patients with cT1b renal tumors. Furthermore, practitioners have extended the role of cryoablation (CA) to treat cT1b tumors in selected patients.

Objective

To evaluate the efficacy of CA compared to PN for cT1b renal tumors.

Design, setting, and participants

We performed a retrospective review of patients who underwent either renal CA (laparoscopic or percutaneous) or PN (robot-assisted) for a cT1b renal mass (>4 cm and ≤7 cm) between November 1999 and August 2014. To reduce the inherent biases of a retrospective study, CA and PN groups were matched on the basis of key variables: tumor size, Charlson comorbidity index (CCI), age, body mass index (BMI), American Society of Anesthesiologists (ASA) score, preoperative serum creatinine, preoperative estimated glomerular filtration rate (eGFR), gender, and solitary kidney. The matching algorithm was 1:1 genetic matching with no replacement.

Outcome measurements and statistical analysis

Survival analysis was performed only for patients diagnosed with renal cell carcinoma according to histopathologic evaluation of a tumor biopsy or resected tumor specimen. Recurrence-free, overall, and cancer-specific survival were analyzed using Kaplan-Meier survival curves. Survival outcomes were compared between groups using the log-rank test.

Results and limitations

A total of 31 patients were treated using CA and 161 using PN during the study period. After matching, there was no significant difference between the PN and CA groups for tumor size (4.6 vs 4.3 cm; p = 0.076), CCI (6 vs 6; p = 0.3), RENAL score (9 vs 8; p = 0.1), age (68 vs 68 yr; p = 0.9), BMI (30 vs 31 kg/m2; p = 0.2), ASA score (3 vs 3; p = 0.3), preoperative creatinine (1.2 vs 1.4 mg/dl; p = 0.2), preoperative eGFR (63 vs 53 ml/min/1.73 m2; p = 0.2), and proportion of patients with a solitary kidney (19% vs 32%; p = 0.4). The total postoperative complication rate was higher for PN than for CA (42% vs 23%; p = 0.10). There was no significant difference in percentage eGFR preservation between PN and CA (89% vs 93%; p = 0.5). The rate of local recurrence was significantly higher for CA than for PN (p = 0.019). There was no significant difference in cancer-specific mortality (p = 0.5) or overall mortality (p = 0.15) between the CA and PN groups.

Conclusions

Patients treated with CA for cT1b renal tumors had a significantly higher rate of local cancer recurrence at 1 yr compared to those treated with PN. Until further studies are performed to clearly define the role of CA in cT1b renal tumors, CA should be reserved for patients with imperative indications for nephron-sparing surgery who cannot be subjected to the risks of more invasive PN.

Patient summary

We evaluated the efficacy of renal cryoablation compared to partial nephrectomy for clinical T1b renal tumors. The cryoablation and partial nephrectomy groups were matched to provide a better comparison. We concluded that renal cryoablation had a higher rate of local cancer recurrence.  相似文献   
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