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101.

Purpose

The preservation of peri-implant bone is one requirement for long-term success of dental implants. The purpose of this study was to evaluate the impact of subcrestal placement on the crestal bone level of immediate versus delayed placed implants after loading.

Materials and methods

In this retrospective study, data of 159 patients who received 330 implants was analyzed. Implants were placed subcrestally, crestally or supracrestally into fresh sockets or healed sites. Vertical bone level height was assessed radiographically and implants were followed up annually. The influence of patient and implant related risk factors for peri-implant bone loss was evaluated using a linear mixed model.

Results

Depth of implant placement was significantly correlated with peri-implant bone loss (P = 0.001, 95% CI). Least effective loss of crestal bone was determined when implants were placed between 1 mm and 1.99 mm subcrestally. Smoking significantly enhanced the risk of peri-implant bone loss (P = 0.04, 95% CI). Immediate implant placement was not positively correlated with peri-implant bone loss (P = 0.51, 95% CI).

Conclusion

Within the limits of this study, implant placement 1.08 mm subcrestally may be recommendable in order to avoid supracrestal expositions of platform-switched titanium implants over time.  相似文献   
102.

Introduction

Poor weight gain is one of the most important mortality hazards in cystic fibrosis (CF) patients. The mechanisms that may hinder body weight regulation are not completely understood. Leptin and its role in fat mass could be related to control of weight gain in CF patients. As the previous data are conflicting, we aimed to investigate serum leptin level in Iranian CF children compared to a control group.

Material and methods

Forty-three CF patients aged from 3 to 120 months and 43 age-matched controls were enrolled. Patients were recruited from the outpatient clinic of the Children''s Medical Center Hospital. Controls were visited in the general outpatient clinic for an annual check-up. Both groups were divided into three subgroups based on age: 3 to 12 months, 13 to 48 months, and 49 to 120 months. Body mass index (BMI) was calculated for all the participants. Serum leptin levels were measured applying a solid phase enzyme-linked immunosorbent assay (ELISA).

Results

Leptin levels and BMI values were significantly different between patients and controls (p = 0.02, p < 0.001, respectively) but only patients aged 13–48 months had significantly higher levels of leptin than age-matched controls (p = 0.016). Overall male patients’ mean leptin level was significantly higher than in female patients (p = 0.032) and male controls (p < 0.001).

Conclusions

Leptin level in our patients was significantly higher than controls. It seems that leptin levels during infancy are higher than in adult patients. Further studies are required on specific genotypes, gender and age to reveal the probable correlation with BMI and leptin levels in CF patients from different ethnic groups.  相似文献   
103.
104.
Neutropenia is a reduction of the absolute neutrophil count (ANC), which could be seen in different conditions, while its association with a number of primary immunodeficiency diseases has been reported. This study was performed in all neutropenic patients who were admitted in a referral pediatric hospital during a 6-year period (2006–2011). One hundred and forty patients with ANC of below 1500/mm3 were investigated in this study. The most common causes of neutropenia were severe congenital neutropenia (41%), aplastic anemia (19%), cyclic neutropenia (11%), hyperimmunoglobulin M syndrome (9%), and fanconi anemia (7%). The patients experienced their first manifestation at a median age of 1 year, while the median diagnostic age was 21 months. Parental consanguinity was present in about half of the cases. The most common clinical manifestations of the patients were sinusitis (62 cases), periodontitis (51 cases), acute diarrhea (39 cases), pneumonia (38 cases), abscess (36 cases), skin rashes (35 cases), and otitis media (31 cases). Twenty two patients (16%) died during the study period. Considering the differential diagnosis of neutropenia, making the diagnosis and appropriate treatments are the keys in management of patients with neutropenia to avoid further complications.  相似文献   
105.
PurposeAdolescence is associated with the onset of depressive symptoms as well as significant increases in health-risk behaviors. Potential explanations for the direction of effects in the association between depressive symptoms and health-risk behaviors include the self-medication/acting out hypothesis (i.e., early depressive symptoms predict increases in risk behaviors over time) and the failure hypothesis (i.e., early participation in health-risk behaviors predicts increases in depressive symptoms over time). The purpose of the present longitudinal study was to assess these competing hypotheses across the high school years, and to examine whether the direction of effects (and therefore the self-medication/acting out and failure hypotheses) may differ depending on the type of risk behavior under consideration.MethodsThe sample consisted of 4,412 adolescents (49% female) who were followed up from grade nine to 12. Adolescents reported on their depressive symptoms and six health-risk behaviors (frequency of alcohol use, amount of alcohol consumed per drinking episode, cigarette smoking, marijuana use, hard drug use, and delinquency). Analyses were conducted with dual trajectory growth curve modeling.ResultsAdolescents who had higher depressive symptoms in grade nine reported faster increases than their peers in smoking, marijuana, and hard drug use across the high school years, supporting the self-medication hypothesis. The failure hypothesis was not supported.ConclusionThe results are important because they suggest that by targeting depressive symptoms during early adolescence, treatment programs may prevent increases in the frequency of these risk behaviors later in adolescence.  相似文献   
106.
The clinical features of interface Candida keratitis after deep anterior lamellar keratoplasty (DALK), may imitate rejection or crystalline keratopathy. We report here an 18-year-old woman presented with red eye, 4 months after undergoing DALK. Slit lamp examination revealed keratic precipitates (KPs) and conjunctival injection. She was prescribed corticosteroid treatment for endothelial rejection by another ophthalmologist because of misdiagnosis, but suffered a recurrence of symptoms after reduction of the corticosteroid treatment. At that time, she was referred to our office. The recurrence persisted despite antibiotic and antifungal therapies. Ten days after treatment with interface irrigation with amphotericin, the infiltration and hypopyon were resolved. Topical steroid was added after 3 months of antifungal monotherapy. Irrigant cultures confirmed the presence of Candida albicans. The corneal graft appeared semi-clear with no signs of infection at 17-month follow-up. We recommend a close follow-up and a timely intervention to prevent the need for more invasive treatment such as penetrating keratoplasty.  相似文献   
107.
Hemophilia A (HA) is an inherited X-linked bleeding disorder caused by a variety of mutations that are distributed throughout the large FVIII gene (F8). The most common mutations in studied populations with severe HA are introns 22 and 1 inversions, gross exon deletions and point mutations in exon 14. The aim of this study was to define the frequency of these common mutations in Iranian population of Azeri Turkish in North West of Iran. Fifty patients with severe HA and forty-three female potential carriers were genotyped by inverse shifting polymerase chain reaction (IS-PCR), long-range PCR, multiplex PCR, and sequencing methods for the detection of Intron 22 and 1 inversions, gross exon deletions, and exon 14 point mutations, respectively. F8 intron 22 inversion was detected in 22 (44 %) out of 50 patients. Moreover, we detected one intron 1 inversion (2 %), and one point mutation in exon 14 (2 %). In this population, 52 % of the patients with hemophilia A did not show to carry a mutation in the analyzed regions by three mentioned methods. F8 intron 22 inversion was the major causative mutation in nearly 50 % of severe HA cases in an Azerbaijani Turkish population, which is similar to the incidence of other populations. IS-PCR is a robust, rapid, efficient, and cost-effective method for the genetic analysis of patients with severe HA and for HA carrier detection, especially in developing countries.  相似文献   
108.
This paper reports a novel green procedure for immobilization of bimetallic Fe/Ni on amorphous silica nanoparticles extracted from rice husk (RH-SiO2). The heterogeneous nanocomposite (Fe/Ni@RH-SiO2) was identified using SEM, EDX, TEM, BET, H2-TPR, TGA, XRD, VSM, ICP-OES, and FT-IR analyses. The Fe/Ni@RH-SiO2 nanocomposite was applied as a powerful catalyst for the reduction of structurally diverse nitro compounds with sodium borohydride (NaBH4) in green conditions. This procedure suggests some benefits such as green chemistry-based properties, short reaction times, non-explosive materials, easy to handle, fast separation and simple work-up method. The catalyst was separated by an external magnet from the reaction mixture and was reused for 9 successive cycles with no detectable changes of its catalytic efficiency.

This paper reports a novel green procedure for immobilization of bimetallic Fe/Ni on amorphous silica nanoparticles extracted from rice husk (RH-SiO2).  相似文献   
109.
110.
Carbapenems are increasingly needed to treat infections caused by drug-resistant gram-negative bacilli (GNB), but carbapenem resistance is increasing. We evaluated the activity of doripenem by broth microdilution against 96 extensively drug-resistant (XDR) Acinetobacter baumannii and Klebsiella pneumoniae isolates from patients with hospital-associated infections. All isolates were non-susceptible to doripenem, but ≥1 doripenem combination demonstrated synergy (fractional inhibitory concentration index: ≤0.5 for 2 agents, ≤0.75 for 3 agents) against 7 (15%) A. baumannii and 23 (48%) K. pneumoniae isolates; doripenem with rifampin and/or polymyxin B were most active. As doripenem has unique potential for use in prolonged infusions, suggested pharmacodynamic (PD) breakpoints range from 2–8 μg/mL; synergistic activity was found for higher proportions of XDR-GNB at higher PD breakpoints with doripenem with amikacin or with rifampin. The clinical utility of these observations requires further study, as treatment options for XDR-GNB infections are limited.  相似文献   
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