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11.
A brain tumor that develops from glial cells is called a glioma. About half of all primary brain tumors form from glial cells. Gliomas are divided into subgroups, depending on the origin of the glial cells. Detection of human cytomegalovirus in tumor tissues of glioma patient was performed for the first time in Iran. These data show an association between human cytomegalovirus (HCMV) and malignant gliomas and suggest that HCMV may play an active role in glioma pathogenesis. Cytomegalovirus surgical biopsy specimens of glioma tissues (n?=?28) and non-tumor brain tissues (n?=?8) were obtained. Total DNA of specimens was extracted, and then, extracted DNA was evaluated by polymerase chain reaction for evidence of HCMV nucleic acids. Here, we show that a high percentage of malignant gliomas are infected by HCMV. Seventy-five percent of grade 4 glioma, 57 % of grade 3 glioma, and 33 % of grade 2 glioma were HCMV positive. All specimens of grade 1 glioma and control tissues were HCMV negative. The relationship between the grade of glioma and the presence of HCMV is significant (P value?=?0.035). Fisher exact test was used for statistical analysis.  相似文献   
12.
Objective: To identify the incidence rate, relative risk, hotspot regions and incidence trend of COVID-19 in Qom province, northwest part of Iran in the first s...  相似文献   
13.
Pemphigus vulgaris (PV) is a chronic autoimmune disorder with potentially fatal outcomes. The aim of this study was to investigate the effect of l ‐carnitine (LC) on secreted frizzled‐related protein‐5 (SFRP5), omentin, visfatin, and glycemic indices in PV patients under corticosteroid treatment. In this randomized, double‐blind, placebo‐controlled clinical trial, 52 patients with PV were divided randomly into two groups to receive 2 g of LC or a placebo for 8 weeks. Serum levels of SFRP5, omentin, visfatin, and also glycemic indices were evaluated at the baseline and end of the study. LC supplementation significantly decreased the serum level of visfatin (95% CI [?14.718, ?0.877], p = .05) and increased the serum levels of SFRP5 (95%CI [1.637, 11.380], p < .006) and omentin (95% CI [9.014, 65.286], p < .01). However, LC supplementation had no significant effects on the serum levels of glycemic factors such as insulin (95% CI [?1.125, 3.056], p = .426), fasting blood sugar (95% CI [?4.743, 3.642], p = .894), homeostatic model assessment of insulin resistance (95% CI [?0.305, 0.528], p = .729), and quantitative insulin‐sensitivity check index (95% CI [?0.016, ?0.010], p = .81). LC supplementation decreased visfatin serum level and increased omentin‐1 and SFRP5 serum levels in patients with PV. However, it has no significant effect on the serum levels of insulin and glycemic indices.  相似文献   
14.
DNA interfaces with nano, micro, and macro materials have gained widespread attention for various applications. Such interfaces exhibit distinct functions and properties not only due to the unique properties of interfacing materials but also sequence- and conformation-dependent characteristics of the DNA. Therefore, DNA interfaces with diverse dimensional materials have advanced our understanding of the interaction mechanisms and the properties of such interfaces. The unique interfacial properties of such novel materials have applications in nanotechnology, biophysics, cell biology, biosensing, and bioelectronics. The field is growing rapidly with the frequent emergence of new interfaces carrying remarkable interfacial character. In this review article, we have classified the DNA interfaces into 0D, 1D, 2D, and 3D categories based on the types of dimensional materials. We review the key efforts made in the last five years and focus on types of interfaces, interfacing mechanisms, and their state-of-the-art applications. This review will draw a general interest because of the diversity in the DNA materials science but also the unique applications that will play a cutting-edge role in biomedical and biosensing research.

DNA interfaces with 0–3 dimensional materials through physisorption and chemisorption mechanisms acquire unique interfacial character for novel biomedical applications.  相似文献   
15.
Triple-negative breast cancer (TNBC) is defined as a type of breast cancer with lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor 2 protein. In comparison to other types of breast cancer, TNBC characterizes for its aggressive behavior, more prone to early recurrence and a disease with poor response to molecular target therapy. Although TNBC is identified in only 25%-30% of American breast cancer cases annually, these tumors continue to be a therapeutic challenge for clinicians for several reasons: Tumor heterogeneity, limited and toxic systemic therapy options, and often resistance to current standard therapy, characterized by progressive disease on treatment, residual tumor after cytotoxic chemotherapy, and early recurrence after complete surgical excision. Cell-surface targeted therapies have been successful for breast cancer in general, however there are currently no approved cell-surface targeted therapies specifically indicated for TNBC. Recently, several cell-surface targets have been identified as candidates for treatment of TNBC and associated targeted therapies are in development. The purpose of this work is to review the current clinical challenges posed by TNBC, the therapeutic approaches currently in use, and provide an overview of developing cell surface targeting approaches to improve outcomes for treatment resistant TNBC.  相似文献   
16.
AIM: To compare the effect of extra-amniotic normal saline solution infusion on its own, and in combination with dexamethasone on the ripening of the cervix and induction of labor. METHODS: A double-blind randomized clinical trial study was performed at Akbar Abadi Teaching Hospital in Tehran, Iran, between March 2002 and March 2003 on 84 pregnant women at a gestational age of 40 weeks or more, and with a Bishop score 相似文献   
17.
BACKGROUND: The optimal method for managing a patient diagnosed with atypical squamous cells of undetermined significance (ASCUS) has not yet been established. The interim guidelines published by the National Cancer Institute suggest that a patient should be referred for colposcopy after the second ASCUS diagnosis within 2 years. AIM: To assess the significance of ASCUS in predicting the presence of underlying squamous intraepithelial lesion (SIL) of the uterine cervix. STUDY POPULATION: Women undergoing colposcopy for ASCUS cytology at a teaching hospital in Tehran University, in the years 1998-2001, considered eligible to enter this retrospective study. RESULTS: Of the 266 patients who underwent colposcopy, 28 (11%) had low-grade squamous intraepithelial lesion (LSIL), 16 (6.3%) had high-grade squamous intraepithelial lesion (HSIL) two (0.8%) had squamous cell carcinoma (SCC), and 48 (18.8%) had flat condyloma. CONCLUSION: Atypical squamous cells of undetermined significance (ASCUS) on a cervical smear is a good marker for detecting underlying SIL and condyloma. Thus, immediate colposcopy and directed biopsy are appropriate follow-up procedures.  相似文献   
18.
PURPOSE: To evaluate the effects of sex and estrus cycle on biphasic anticonvulsant and proconvulsant modulation of seizure threshold by morphine. METHODS: The threshold for the clonic seizures (CST) induced by acute intravenous administration of gamma-aminobutyric acid (GABA)-antagonist pentylenetetrazole (PTZ) was assessed in male and female mice. Estrus cycle was assessed by vaginal smears. The effect of removing circulating sex hormones was assessed by gonadectomy. RESULTS: At baseline, diestrus females had a higher CST compared with males and estrus females. Morphine at lower doses (0.5-3 mg/kg) had a significant anticonvulsant effect in males and estrus females compared with that in vehicle-treated controls, whereas female mice in diestrus phase showed a relative subsensitivity to this effect. Morphine at higher doses (30 and 60 mg/kg) significantly decreased CST in males and diestrus females, with less relative effect in estrus mice. In both phases, morphine exerted stronger effects in males compared with females. Ovariectomy brought the baseline CST to the male level and resulted in significant expression of both phases of morphine effect but did not abolish the sex difference in responsiveness to morphine. CONCLUSIONS: The biphasic modulation of seizure threshold is subject to both constitutive sex differences in sensitivity to morphine and hormonal fluctuations during the estrus cycle.  相似文献   
19.
20.

Background

Bearing surface wear and osteolysis are major factors limiting the durability of total hip arthroplasty (THA). Second generation annealed highly cross-linked polyethylene (HXLPE) and ceramics were introduced to THA for their excellent wear rates. However, there is little data comparing the wear rates of metal and ceramic heads on second generation HXLPE.

Methods

Sixty patients who received a noncemented THA with a 32- or 36-mm delta ceramic head were matched with 60 THAs with a 32- or 36-mm metal head based on gender, head size, follow-up, and University of California, Los Angeles activity score. Linear and volumetric wear rates were measured.

Results

At mean 6-year follow-up, the mean linear wear rates were 0.012 mm/y (standard deviation [SD] 0.045; 95% confidence interval [CI] 0.001-0.024) and 0.018 mm/y (SD 0.025; 95% CI 0.012-0.025) for the ceramic and metal groups, respectively (P = .724). The mean volumetric wear rates for the ceramic and metal head groups were 11.9 (SD 43.0; 95% CI 0.7-23.0) and 17.3 (SD 23.9; 95% CI 11.1-23.4), respectively. No significant differences were detectable in either the mean linear or volumetric wear rates (P = .380 and P = .398, respectively).

Conclusion

Second generation HXLPE had low wear rates and we were unable to detect a significant difference in wear rates with 32- or 36-mm metal and ceramic heads. We believe that this is due to the excellent tribological properties of second generation HXLPE. We continue to use ceramic as standard of care because of issues of trunnionosis with metal heads.  相似文献   
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