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1.
Ameloblastic carcinoma (AC) is an aggressive malignant epithelial odontogenic tumor. It may appear de novo or originate from a pre-existing ameloblastoma or odontogenic cyst. To our knowledge, an AC that originates from the anterior skull base has not been reported before in the English literature. We report a case of an AC that originated from the anterior skull base and invaded the dura of the anterior fossa and discuss its clinical course and treatment.  相似文献   
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After the chondrogenic potential of free grafts of perichondrium was shown in several experimental studies, perichondrium has been used to reconstruct cartilage tissue in various clinical situations. This study investigates the effects of human amniotic fluid on neochondrogenesis from free perichondrial grafts in a rabbit model. Since this fluid contains high concentrations of hyaluronic acid, hyaluronic acid-stimulating activator, growth factors, and extracellular matrix precursors during the second trimester, it may have a stimulating effect on neochondrogenesis. Perichondrial grafts, measuring 20 x 20 mm2 were obtained from the ears of 144 New Zealand young rabbits and were sutured over the paravertebral muscles. The rabbits were randomly divided into three groups with 48 rabbits per group. In group 1, 0.3 ml human amniotic fluid, and in group 2, 0.3 ml saline were injected underneath the perichondrial grafts. Group 3 formed the control group in which no treatment was given. Histologically, neochondrogenesis was evaluated in terms of cellular form and graft thickness at 2, 4, 6, and 8 weeks after surgery. In group 1, the mature cartilage was generated quickly and the cartilage plate in this group was significantly thick and extensive when compared with groups 2 and 3 at 8 weeks ( p<0.05 ANOVA). In conclusion, our study shows that human amniotic fluid enhances neochondrogenesis from free perichondrial grafts. The rich content of hyaluronic acid and growth factors possibly participate in this result.  相似文献   
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OBJECTIVE: To evaluate the efficacy of diazepam and atropine sulfate premedication in preventing nausea and vomiting after strabismus surgery under general anesthesia. METHODS: Fifty children age 4 to 15 years who underwent strabismus surgery at Cukurova University Medical Faculty, Department of Ophthalmology, from February 2000 to June 2000 were randomized into 2 groups: 25 children in the control group did not receive premedication, whereas 25 children in the treatment group received premedication with 0.15 mg/kg diazepam and 0.015 mg/kg atropine sulfate. Occurrence of postoperative nausea and vomiting (PONV) was recorded. RESULTS: The incidence of PONV was lower in the premedicated group (P <.018, chi(2) test). CONCLUSIONS: It is concluded that diazepam and atropine sulfate premedication decreases nausea and vomiting after strabismus surgery.  相似文献   
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Silane-coated silica particle solutions (ISolate(TM) and PureSperm)TM)) and iodixanol (OptiPrep(TM)) were compared to polyvinylpyrrolidone (PVP)-coated silica particles (Percoll(TM)) in their efficacy to recover spermatozoa by gradient centrifugation for use in assisted reproductive procedures. Efficacy was assessed in terms of percentages of sperm recovery, sperm vitality and motility, normal sperm morphology and normal sperm chromatin condensation. No significant difference was found in the recovery of spermatozoa for men with both normal sperm counts and oligozoospermia, between PVP-coated and silane-coated particle solutions. Iodixanol had significantly lower sperm recovery compared to the other products. Sperm vitality, progressive motility, normal morphology and normal chromatin condensation did not differ significantly between any of the sperm isolation products.   相似文献   
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A survey study was conducted to investigate the possible effects of mobile phone on headache, dizziness, extreme irritation, shaking in the hands, speaking falteringly, forgetfulness, neuro-psychological discomfort, increase in the carelessness, decrease of the reflex and clicking sound in the ears. There is no effect on dizziness, shaking in hands, speaking falteringly and neuro-psychological discomfort, but some statistical evidences are found that mobile phone may cause headache, extreme irritation, increase in the carelessness, forgetfulness, decrease of the reflex and clicking sound in the ears.  相似文献   
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Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts to diminish biomaterial-related infections.  相似文献   
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BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS.  相似文献   
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Plasmid DNA vectors have been constructed with minigenes encoding a single cytotoxic T lymphocyte (CTL) epitope from either the M2 protein of respiratory syncytial virus (RSV) or from the nucleoprotein of measles virus (MV) with or without a signal sequence (also called secretory or leader sequence). Following intradermal immunization, plasmids in which the CTL epitopes were expressed in-frame with the signal sequence were more effective at inducing peptide- and virus- specific CTL responses than plasmids expressing CTL epitopes without the signal sequence. This immunization resulted in protection against MV-induced encephalitis and a significant reduction in viral load following RSV challenge. The reduction of viral load following RSV challenge was abrogated by prior injection with anti-IFN-gamma antibodies. These results highlight the ability of epitope-based DNA immunization to induce protective immune responses to well-defined epitopes and indicate the potential of this approach for the development of vaccines against infectious diseases.   相似文献   
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