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41.
Seraj JM Yazdani N Ashtiani ZO Seraj SM Hasheminasab SM Memar B Mirashrafi F Borghei H Yazdani J Mostaan LV 《Pathology, research and practice》2011,207(12):758-761
In this study, we investigated the prevalence of human papilloma virus (HPV) infection and TP53 expression in patients with squamous cell carcinoma (SCC) of the tongue and, subsequently, its significance in cervical lymph node metastases and tumor differentiation. Sections of formalin-fixed, paraffin-embedded tissue blocks from 94 histologically confirmed tongue SCC cases were investigated in this study. Immunohistochemistry was used to study TP53 expression, and polymerase chain reaction (PCR) was performed for the detection of high risk HPV types (16 and 18). The frequency of HPV-16 and HPV-18 infection was 10.6% and 16%, respectively. Overexpression of TP53 was observed in 70.2% of patients. Young patients (aged below 45 years) comprised 20% of all patients. There was no significant association between TP53, HPV-16, or HPV 18 presence and higher stages of the tumor, tumor differentiation, or presence of nodal metastasis. Although an association between head and neck SCC and HPV infection is being recognized and reported, our data implicate that HPV infection or TP53 expression does not play a significant role in oral tongue SCC pathogenesis, differentiation, or metastasis, as seen in our patients. 相似文献
42.
Mostaan LV Khorsandi MT Sharifian SM Shandiz FH Mirashrafi F Sabzari H Badiee R Borghei H Yazdani N 《Pathology, research and practice》2011,207(7):448-451
The aim of this article was to evaluate the expression of E-cadherin and CD44 adhesion molecule in oral tongue squamous cell carcinoma (SCC) since inappropriate expression of adhesion molecules raises the metastatic ability of the tumor cells.Biopsy specimens from 92 patients with tongue SCC were examined for the expression of E-cadherin and CD44 by immunohistochemistry. The relationship of immunoreactivity with tumor stage and cervical lymph node metastasis was then analyzed.Sixty-one patients (66.3%) had reduced or negative staining for CD44. Weak or absent staining for E-cadherin was seen in 14 patients (15.21%). Cervical lymph node metastasis is associated with decreased or negative staining for CD44, but no association was found between E-cadherin immunoreactivity and nodal metastasis.Our study reveals that reduced expression of CD44 could be an indicator of high invasiveness of tumor by increasing cervical lymph node metastasis. 相似文献
43.
N. Yazdani M. T. Khorsandi Ashtiani M. M. Zarandy S. J. Mohammadi H. Ghazavi E. Mahrampour P. Amiri M. M. Amoli 《International journal of immunogenetics》2013,40(6):488-491
Several pieces of evidence support the involvement of immune system in Menière's disease (MD). Macrophage migration inhibitory factor (MIF) plays a key role in immune‐mediated reactions. Several studies have shown an association between MIF gene polymorphisms and susceptibility to various inflammatory and autoimmune disorders. The aim of this study was to explore the association between MIF‐173 G/C polymorphism and MD in an Iranian population. In this case–control association study, MD cases (N = 72) were recruited and were comprised of definitive MD (N = 58) and probable MD (N = 14) subjects. Normal healthy subjects (N = 100) were also included. Genotyping for MIF‐173 G/C polymorphism was carried out using PCR‐RFLP technique. There was a significant increase in genotype GG in patients with MD compared with the control group. (GG vs. GC + CC, P = 0.02, OR = 2.08, 95% CI: 1.02–4.3). This was more significant when definitive MD was stratified and compared with the controls (GG vs. GC + CC, P = 0.009, OR = 2.6, 95% CI = 1.19–6.18). This study's result indicates the potential role of MIF in MD of which further evaluation is required. Also, the more significant association between MIF gene polymorphism and definitive MD designates the involvement of specific pathogenic mechanisms which may be considered as a marker for diagnosis. 相似文献
44.
Ahmadi J 《Journal of substance abuse treatment》2002,22(3):157-159
The aim of this study was to assess the efficacy of 1-, 2-, and 4-mg-per-day sublingual doses of buprenorphine in the maintenance treatment of heroin-dependent patients over a 17-week treatment period. Subjects were randomized to three dosage groups. Participants consisted of 105 heroin addicts (102 men and 3 women) who met the DSM-IV criteria for opioid dependence and were seeking treatment. Subjects received buprenorphine at a dose of 1, 2, or 4 mg per day and were treated in an urban outpatient clinic, including a weekly 1-hour individual counseling session. Days retained in treatment were measured. Overall, 49 patients (46.7%) completed the 17-week study. Completion rates by dosage group were 34.3% for the 1 mg dose group, 42.9% for the 2 mg dose group, and 62.9% for the 4 mg dose group. Retention in the 4 mg dose group was significantly better than in the 1 mg dose group (P = .017). None of the other comparisons was significant. The results support the efficacy and safety of buprenorphine for outpatient treatment of heroin dependence and seem to indicate that the highest dose (4 mg) of buprenorphine was the best of the three doses for Iranian heroin addicts to increase their retention in treatment. 相似文献
45.
[目标]:研究不同和相同读片人对息肉直径进行体外自动测量时所得结果的一致性。[方法]:用16排CT扫描两个模型(QRM和Whiting模型),两个模型都包含有直径和体积已知的模拟息肉。两位读片人用三种方式来估计息肉的直径:软件测量(手工)、手工边界识别(半自动)及自动软件分割(全自动)。[结果]:对同一读片人,当使用全自动方法时,95%一致性极限范围最小(QRM范围:0.39mm~0.48mm;Whiting范围:0.24mm~0mm)。手工估计测量的极限范围大约比全自动方法要大10倍(QRM范围:3.57mm~3.21mm,Whiting范围:3.2mm~2.02mm)。全自动方法对体积的估计范围最小(范围:24.2mm^3~24.1mm^3;而半自动测量的范围为97.9mm^3~102.9mm^3.对不同读片人,当使用全自动方法时,测得直径的一致性范围最小(QRM范围:0.12mm;Whiting范围:0.16mm),而使用手工方法的一致性范围大约是全自动方法的18倍(QRM范围2.87mm;Whiting范围:2.18mm)。[结论]:通过全自动方法来测量息肉直径和体积在技术上是可行的,可使不同和相同读片人的测量结果实现更高的一致性。 相似文献
46.
47.
Yono M Pouresmail M Takahashi W Flanagan JF Weiss RM Latifpour J 《Naunyn-Schmiedeberg's archives of pharmacology》2005,372(3):251-255
To examine the differences between spontaneous and streptozotocin (STZ)-induced diabetes, four parallel studies were performed;
three studies of diabetes-prone BB (BBDP/Wor) rats maintained for 8, 16, and 32 weeks and one study of STZ-injected diabetes-resistant
BB (BBDR/Wor) rats maintained for 32 weeks. Each diabetic study has three groups of rats: a control group; a euglycemic group,
which received sufficient amounts of insulin; and a hyperglycemic group, which received a suboptimal dose of insulin. The
extent of tissue weight changes was generally shown to be less dramatic in the euglycemic diabetic than in the hyperglycemic
diabetic rats. STZ-induced diabetes increased the bladder weight more dramatically (up to 3-fold) than did spontaneous diabetes
(up to 2-fold). Furthermore, a significant decrease in the size of the adrenal gland (20%) and testis (10%) is observed only
with spontaneous diabetes, whereas a significant decrease in the size of the ventral prostate (30%) is observed only with
STZ-induced diabetes, although the serum testosterone levels are similar in both groups. Our data demonstrate that there are
differences in the effect of insulin treatment on the tissue size of the genitourinary tract between spontaneously developed
and streptozotocin-induced diabetes in BB rats. 相似文献
48.
Keyak JH Kaneko TS Tehranzadeh J Skinner HB 《Clinical orthopaedics and related research》2005,(437):219-228
Hip fracture related to osteoporosis and metastatic disease is a major cause of morbidity and mortality. An accurate and precise method of predicting proximal femoral strength and fracture location would be useful for research and clinical studies of hip fracture. The goals of this study were to develop a structural modeling technique that accurately predicts proximal femoral strength; to evaluate the accuracy and precision of this predicted strength on an independent data set; and to evaluate the ability of this technique to predict fracture location. Fresh human cadaveric proximal femora with and without metastatic lesions were studied using computed tomography scan-based three-dimensional structural models and mechanical testing to failure under single-limb stance-type loading. The models understated proximal femoral strength by an average of 444 N, and the precision of the predicted strength was +/- 1900 N. Therefore, the ability to predict hip strength in an individual subject is limited primarily by the level of precision, rather than accuracy. This level of precision is likely to be sufficient for many studies of hip strength. Finally, these models predict fractures involving the subcapital and cervical regions, consistent with most fractures produced experimentally under single-limb stance-type loading. 相似文献
49.
Vitamin A (Vit A) and its derivatives have recently been reported to be implicated in synaptic plasticity. In this study, the possible effect of Vit A and its precursor, beta-carotene on acute seizure and kindling, induced by pentylenetetrazole (PTZ) was assessed. Vit A and beta-carotene were evaluated for their ability to: (1) elevate the threshold of clonic seizures induced by i.v. infusion of PTZ; (2) suppress the seizures (clonic and tonic) and lethality induced by i.p. PTZ in PTZ-kindled mice (anticonvulsant effect); (3) attenuate the development of sensitization to convulsive and lethal effects of i.p. PTZ in kindled mice (anti-epileptogenic effect). Diazepam was employed as positive control. All the drugs showed anti-epileptogenic effect against PTZ-induced tonic seizures and lethality. Vit A and beta-carotene had no effect on clonic seizures threshold and also on tonic seizures and lethality induced by PTZ in kindled mice. Non-genomic and genomic mechanisms could be involved in the anti-epileptogenic effect of Vit A and beta-carotene. 相似文献
50.
PURPOSE OF REVIEW: To describe the reconstructive techniques in urinary diversion utilized by the gynecologist after radical pelvic surgery. The radical resection of pelvic malignancies remains an important part of the armamentarium of the gynecological oncologist. Techniques in continent urinary diversion should be used to restore these women to an acceptable quality of life. Reconstruction is the surgical challenge of this and future generations of pelvic surgeons. It is imperative that pelvic surgeons begin to consider the quality of life and the functional reintegration into society of the patients we are able to salvage with these radical surgical efforts. RECENT FINDINGS: The advent of continent urostomies has significantly improved the quality of life of patients who undergo radical tumor resection involving the bladder. Such techniques prevent the need for urostomy bags, and thus all the physical and psychological ramifications associated with them. We will review recent literature associated with the complications and the management of these complications. SUMMARY: Familiarity with techniques in continent urinary diversion by the gynecologist is an important part of the management of patients with gynecological malignancies and permanent bladder atony. 相似文献