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101.
This study compares the effect of tooth clenching and grinding on supra- and infrahyoid electromyographic (EMG) activity during different laterotrusive jaw posture tasks. The study included 30 healthy subjects with natural dentition and bilateral molar support, 15 with bilateral canine guidance and 15 with bilateral group function. Bipolar surface electrodes were located on the left and right supra- and infrahyoid muscles. EMG activity was recorded during the following tasks: A. eccentric grinding from intercuspal position to the right lateral edge-to-edge contact position; B. clenching in right edge-to-edge lateral contact position; C. concentric grinding from right lateral edge-to-edge contact position to intercuspal position. EMG activity was not significantly different between tasks on the working side, nonworking side, or between both sides, in subjects with canine guidance or group function (Wilcoxon rank-sum test). When comparing EMG activity by occlusal scheme, no significant differences were found either on the working side or the non-working side (Mann-Whitney U test). This result suggests that supra- and infrahyoid EMG activity in its predominant stabilizing role of the hyoid bone is not significantly modified by the type of laterotrusive occlusal scheme.  相似文献   
102.
To evaluate the effect of topography in nanoscale, titanium surfaces were bombarded by argon ions (a chemically inert gas), in an atmosphere of plasma. The effects of surface parameters on morphology, adhesion, proliferation, and MC3T3‐E1 preosteoblasts differentiation were analyzed. Nontreated (smooth) surfaces were used as a control. The levels of average roughness (Ra) observed in bombarded and smooth titanium surfaces were of 95 and 14 nm, respectively. The wettability increased on treated surfaces. The number of attached cells (30 and 60 min) was significantly higher on the bombarded surface. The cell proliferation after 3 and 7 days was also significantly higher on the ion‐bombarded surface. In addition, the ALP activity and expression of osteocalcin were higher in cells grown on the treated surface. The results showed that bombardment with argon ions increased the roughness and the wettability of the Ti surface, promoting a significant increase in the adhesion, proliferation, and differentiation of preosteoblasts.  相似文献   
103.
104.
Moraxella catarrhalis causes acute otitis media in children and lower respiratory tract infections in adults and elderly. In children the presence of antibodies against the highly conserved outer membrane protein CD correlates with protection against infection, suggesting that this protein may be useful as a vaccine antigen. However, native CD is difficult to purify, and it is still unclear if recombinant CD (rCD) is a valid alternative. We performed a side-by-side comparison of the immunogenicities and efficacies of vaccine formulations containing native CD and rCD with adamantylamide dipeptide as the mucosal adjuvant. Intranasal vaccination of mice stimulated the production of high CD-specific antibody titers in sera and of secretory immunoglobulin A in mucosal lavages, which cross-recognized both antigens. While vaccination with native CD increased the number of interleukin-2 (IL-2)- and gamma interferon-producing cells, rCD mainly stimulated IL-4-secreting cells. Nevertheless, efficient bacterial clearance was observed in the lungs of challenged mice receiving native CD and in the lungs of challenged mice receiving rCD (96% and 99%, respectively). Thus, rCD is a promising candidate for incorporation in vaccine formulations for use against M. catarrhalis.  相似文献   
105.
Fertilization problems are the major problems that may be faced in 30–55% of the patients during an intracytoplasmic sperm injection (ICSI) cycle. A successful oocyte activation depends on factors related to both sperm and oocyte, and one of the important factors that mediates the process is Ca2+ concentration within the oocyte. Artificial oocyte activation (AOA) is a method used for fertilization problems that commonly involve the usage of Ca2+ ionophores and is usually used in problems such as total fertilization failure (TFF) and globozoospermia. The aim of the present study was to investigate possible effects of AOA for different groups of patients with fertilization failure. Four groups of patients (previous TFF, low oocyte number, severe sperm quality, and frozen sperm (FS) group) that underwent ICSI with AOA were included in the study. All groups had similar control groups with same indications except TFF, where AOA was not performed. Fertilization rates were significantly higher in the TFF group than those observed in other AOA groups. Fertilization rates and quality of embryos observed in the remaining AOA groups were higher than those of the controls, which were statistically insignificant. Prgenancy rates were higher in all AOA groups compared to the controls, although the differences were significant in FS group only. Quality of embryos and pregnancy rates were lower in the TFF group compared to the remaining AOA groups indicating possible concomitant problems. Fertilization rates, quality of embryos and pregnancy rates seemed to be increased in all indication groups suggesting that not only TFF patients but also a wide variety of patients with different indications may benefit from AOA.

Abbreviations: ICSI: Intracytoplasmic sperm injection; ARTs: Assisted reproductive techniques; Ca: Calcium; AOA: Artificial oocyte activation; TFF: Total fertilization failures; OAT: Oligoasthenoteratozoospemia; IVF: In vitro fertilization; SOAT: Severe OAT; LON: Low ooctye number; FS: Frozen sperm; hCG: human chorionic gonadotrophin; PVP: polyvinylpyrrolidone; HSA: human serum albumin  相似文献   

106.

Background

Resident doctors are continuously exposed to prolonged working hours and night shifts, making them susceptible to the many physical, psychological, and cognitive side effects of sleep deprivation, which may affect their quality of life. Therefore, this study aimed to determine the prevalence of sleep penury in resident doctors and to assess the association between self-apprehended sleepiness and quality of life.

Methods

A cross-sectional study was carried out in the governmental hospitals in the North of the West Bank between May 2017 and September 2017. Doctors enrolled in residency programmes completed questionnaires about general, sociodemographic, and sleep characteristics. The doctors completed the Arabic Version of the Epworth Sleepiness Scale (ArESS) to assess subjective daytime sleepiness and the RAND 36-item short-form health survey (SF-36) to determine quality of life.

Results

A total of 101 participants were enrolled. Daytime sleepiness was observed in 37.6% (n?=?38) of the participants with an ESS score of ≥10. There was a notable negative correlation between the ESS and quality of health index in the physical composition (r?=???0.351, p?<?0.001) demonstrated in the following four subscales: the physical functioning (p?<?0.001), role limitations due to physical health (p?=?0.045), body pain (p?=?0.036), and general health (p?<?0.001) components of the SF-36 scale. Females and residents of the centre region had poorer mental quality (p?=?0.006 and 0.020, respectively).

Conclusions

More than one third of the resident doctors suffer from daytime sleepiness according to the ESS. This was proven to significantly affect several aspects of their quality of life, including physical function and health, body pain, and general health. Sleep deprivation and improvement of quality of life require health promotion actions among medical residents.
  相似文献   
107.

Objective

Aim is to compare the glycemic level among patients before, and after local anesthesia containing adrenaline 1:80,000 among patients who need dental extraction.

Materials and methods

60 patients were randomly selected including 30 healthy and 30 with a diabetes history for this study in Riyadh city. First the blood glucose level was measured before administering local anesthesia containing adrenaline after taking their history with glucocheck according to instructions, then blood Sugar level was recorded after administering local anesthesia containing adrenaline 1:80,000 concentrations. Blood sugar level was also checked 5 min after the tooth extraction procedure.

Results

There were no significant results found after the administration of local anesthesia containing adrenaline in both healthy and diabetic patients (p > 0.05). However, change of significance (p < 0.05) was noticed in diabetic patients who had not taken their hypoglycemic medication; there was a rise in their blood glucose level after extraction.

Conclusion

The study concluded no significant effect on the glycemic level of patients after the administration of local anesthesia containing adrenaline 1:80,000 in healthy and diabetic patients whether hypoglycemic medication was taken or not but a rise in blood sugar level was found among diabetic patients who did not take their hypoglycemic medications undergoing tooth extraction.  相似文献   
108.
109.
Sperm or testicular tissue cryopreservation is performed in cases of male infertility as a treatment for the preservation of fertility. When these sperm cells are used in assisted reproductive techniques, fertilisation rates, developmental and implantation potential of embryos decrease and the abortion rates increase. In the present work, differences of both phosphorylation and expression levels of p53 and Mitogen‐activated protein kinases (MAPK) proteins were analysed in 61 individual sperm samples before and after cryopreservation. We observed that p53 protein residue at Ser 15 was phosphorylated after cryopreservation. Because MAPK pathway activations may be involved in p53 phosphorylation, MAPK/ERK, Stress‐activated protein kinases (SAPK)/JNK and p38MAPK proteins were also investigated. Analysis showed that p38MAPK phosphorylations increased significantly. However, ERK and JNK expressions and phosphorylations decreased, although the differences were not statistically significant. According to our results, it may be suggested that cryopreservation process activates p53 via p38 MAPK pathway that subsequently causes apoptosis, which may be related to sperm parameters.  相似文献   
110.
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