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31.
Objective: The objective of this study was to explore effects of implant macrodesign and diameter on initial intraosseous stability and interface mechanical properties of immediately placed implants. Material and method: Mandibular premolars of four fresh‐frozen human cadavers were extracted. Ø 4.1/4.8 mm ITI® TE®, Ø 4.1 and 4.8 mm solid screw synOcta® ITI® implants were placed into freshly prepared extraction sockets. Resonance frequency analysis was conducted to quantify primary implant stability quotient (ISQ). Installation torque value (ITV) and removal torque value (RTV) of the implants were measured using a custom‐made strain‐gauged torque wrench connected to a data acquisition system at a sample rate of 10,000 Hz. The vertical defect depth around the collar of each implant was measured directly by an endodontic spreader. The bone–implant contact was determined in digitalized images of periapical radiographs and expressed as percentage bone contact. Results: The ISQ values of the TE® implant was higher than the Ø 4.1 mm implant (P<0.01), and comparable with the Ø 4.8 mm implants (P>0.05). ITVs and RTVs of TE® and Ø 4.8 mm implants were higher than the Ø 4.1 mm implant, although the differences between groups were statistically insignificant (P>0.05). The vertical defect depths around all types of implants were similar. In the radiographic analyses, percentage bone–implant contact of the TE® and Ø 4.8 mm implants were comparable at the marginal bone region and both were higher than that of the Ø 4.1 mm ITI® implant. Nonparametric correlations between groups revealed a significant correlation between ITV and RTV (r=0.838; P<0.001), but not between ISQ values and ITVs and RTVs (P>0.05). Conclusion: Immediately placed ITI® TE® implant leads to initial intraosseous stability and interface mechanical properties comparable with a wide diameter implant.  相似文献   
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PURPOSE: To investigate the refractive results of clear corneal incision performed at the steepest meridian of pre-existing corneal astigmatism. METHODS: One hundred eighty-two patients with astigmatism > 0.75 diopters (D) were evaluated. Superior, temporal, nasal, superotemporal, or superonasal clear corneal incisions were performed at the steep meridian. Refraction, visual acuity, and topography values were evaluated, and changes in surgically induced astigmatism were calculated by vector analysis using the Fourier formula. Paired t test was used to compare mean values. RESULTS: Postoperative cylinder values showed minor changes in all groups, except the nasal group. Nasal incision increased preoperative cylinder from 1.13 D to 1.83 D 6 months after surgery. Temporal and superotemporal incisions resulted only in small astigmatic changes. Conversely, superior, superonasal, and nasal incisions induced more pronounced astigmatism. CONCLUSIONS: Performing clear corneal incision for phacoemulsification of cataract at the steep meridian resulted in small changes with temporal incisions, whereas nasal incisions resulted in higher surgically induced astigmatism.  相似文献   
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Aim

To examine the influence of obesity on the patient characteristics and clinicopathologic features of endometrial cancer, and to find how treatment and prognosis were affected by obesity in women with endometrial cancer.

Methods

The data of 370 consecutive women operated for endometrial cancer were retrospectively reviewed. Patients were divided into three categories as <25, 25–29.9 and ≥30 according to BMI. All patients underwent primary surgical treatment including total abdominal hysterectomy, bilateral oophorectomy and peritoneal cytology. Pelvic lymphadenectomy was carried out for all patients except for those with no myometrial invasion regardless of the tumor grade or for whom it was technically impossible. Paraaortic lymphadenectomy was performed when pre- and intraoperative assessments suggested non-endometrioid or grade 3 endometrioid cancer, >50?% myometrial invasion and cervical involvement.

Results

Patients with a BMI (body mass index) of <25 were significantly younger. Patients with a BMI of ≥30 were statistically less likely to have >50?% myometrial invasion and more likely to have stage I disease. There were no significant differences in the incidences of positive pelvic and paraaortic lymph nodes and tumor grades between the three groups. Also, there were no differences in surgery type, the mean of removed pelvic and paraaortic lymph node number, hospital stay, blood loss and complications between the groups. The patients with a BMI of ≥30 had significantly longer operating time. There were no statistically significant differences in recurrences, the median number of months at recurrence or the site of recurrence between the three groups, as well as the 5-year overall and disease-free survival of patients. Multivariate proportional hazard models identified stage III and IV disease as significant covariates for mortality rates, while stage III and IV disease, hypertension and pelvic irradiation were identified as significant covariates for recurrence rates.

Conclusion

Positive peritoneal cytology, deep myometrial invasion and stage II–IV endometrial cancer were significantly more common in patients with a BMI of <25. There were no significant differences in tumor grade, surgical technique, surgical morbidity or adjuvant radiotherapy between the BMI groups. Recurrence and cancer-related mortality rates were not affected by the BMI.  相似文献   
35.
Caffeine is widely consumed among elite athletes for its well-known ergogenic properties, and its ability to increase exercise performance. However, studies to date have predominantly focused on the anhydrous form of caffeine in male participants. The aim of the study was to investigate the effect of caffeinated coffee ingestion on lower-upper body muscular endurance, cognitive performance, and heart rate variability (HRV) in female athletes. A total of 17 participants (mean ± standard deviation (SD): age = 23 ± 2 years, body mass = 64 ± 4 kg, height = 168 ± 3 cm) in a randomized cross-over design completed three testing sessions, following the ingestion of 3 mg/kg/bm of caffeine (3COF), 6 mg/kg/bm of caffeine (6COF) provided from coffee or decaffeinated coffee (PLA) in 600 mL of hot water. The testing results included: (1) repetition number for muscular endurance performance; (2): reaction time and response accuracy for cognitive performance; (3): HRV parameters, such as standard deviation of normal-to-normal (NN) intervals (SDNN), standard deviation of successive differences (SDSD), root mean square of successive differences (RMSSD), total power (TP), the ratio of low- and high-frequency powers (LF/HF), high-frequency power (HF), normalized HF (HFnu), low-frequency power (LF), and normalized LF (LFnu). A one-way repeated measures ANOVA revealed that 3COF (p = 0.024) and 6COF (p = 0.036) improved lower body muscular endurance in the first set as well as cognitive performance (p = 0.025, p = 0.035 in the post-test, respectively) compared to PLA. However, no differences were detected between trials for upper body muscular endurance (p = 0.07). Lastly, all HRV parameters did not change between trials (p > 0.05). In conclusion, ingesting caffeinated coffee improved lower body muscular endurance and cognitive performance, while not adversely affecting cardiac autonomic function.  相似文献   
36.

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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Objective

We aimed to describe the typical clinical and laboratory features and treatment of children diagnosed with multisystem inflammatory syndrome in children (MIS-C) and to understand the differences as compared to severe/critical pediatric cases with COVID-19 in an eastern Mediterranean country.

Methods

Children (aged <18 years) who diagnosed with MIS-C and severe/critical pediatric cases with COVID-19 and were admitted to hospital between March 26 and November 3, 2020 were enrolled in the study.

Results

A total of 52 patients, 22 patients diagnosed with COVID-19 with severe/critical disease course and 30 patients diagnosed with MIS-C, were included in the study. Although severe COVID-19 cases and cases with MIS-C share many clinical and laboratory features, MIS-C cases had longer fever duration and higher rate of the existence of rash, conjunctival injection, peripheral edema, abdominal pain, altered mental status, and myalgia than in severe cases (p<0.001 for each). Of all, 53.3% of MIS-C cases had the evidence of myocardial involvement as compared to severe cases (27.2%). Additionally, C-reactive protein (CRP) and white blood cell (WBC) are the independent predictors for the diagnosis of MIS-C, particularly in the existence of conjunctival injection and rash. Corticosteroids, intravenous immunoglobulin (IVIG), and biologic immunomodulatory treatments were mainly used in MIS-C cases rather than cases with severe disease course. There were only three deaths among 52 patients, one of whom had Burkitt lymphoma and the two cases with severe COVID-19 of late referral.

Conclusion

Differences between clinical presentations, acute phase responses, organ involvements, and management strategies indicate that MIS-C might be a distinct immunopathogenic disease as compared to pediatric COVID-19. Conjunctival injection and higher CRP and low WBC count are reliable diagnostic parameters for MIS-C cases.

Key Points
? MIS-C cases had longer fever duration and higher rate of the existence of rash, conjunctival injection, peripheral edema, abdominal pain, altered mental status, and myalgia than in severe/critical pediatric cases with COVID-19.
? Higher CRP and low total WBC count are the independent predictors for the diagnosis of MIS-C.
? MIS-C might be a distinct immunopathogenic disease as compared to pediatric COVID-19.
  相似文献   
40.
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