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11.
A potential molecular marker associated with cancer susceptibility as well as metastasis, prognosis and adverse survival, is the L-myc gene. The studies of lung cancer patients from different populations have yielded controversial results. We studied 64 nonsmall cell lung cancer (NSCLC) patients and 37 healthy controls of Turkish origin for L-myc gene polymorphism. Our aim was to test the hypothesis that there was association between L-myc S allele in NSCLC and predisposition to the disease and TNM stage indicating tumor size, node classification and metastasis. Polymerase chain reaction restriction fragment length polymorphism and agarose gel electrophoresis were used to determine the L-myc oncogene genotypes. We found no significant difference, both in the distribution of the LL, LS and SS genotypes and in the allelic frequencies, between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data between the patient group and the control group; that is, the frequencies of L-myc alleles were, L and S, 0.59 and 0.41, 0.60 and 0.40, respectively. Our data concerning age, sex, size of tumors, histological type of tumors showed no significant association with L-myc genotype. However, a higher frequency of L-myc S allele in the squamous cell carcinoma compared to other histological groups was found, although this difference was not statistically significant. No association was found between the L-myc RFLP and increased risk of metastasis either to the lymph nodes or to other organs. Our results suggested that L-myc gene polymorphism was not a suitable prognostic marker of metastatic development in Turkish NSCLC patients.  相似文献   
12.
The reductive etherification reaction (RER) of carbonyl groups (aldehydes or ketones) through silane as a reducing agent together with Bronsted or Lewis acid affords the synthesis of symmetrical and unsymmetrical ethers. This strategy is applied at the macromolecular level for the first time in 1993, and isophthalaldehyde is self-polymerized in the presence of triethylsilane (Et3SiH)/ tritylperchlorate (TrClO4) to yield polyethers with low to moderate molecular weights. Next, the polyethers with alternating structures are achieved by reacting isophthalaldehyde with bis(trimethylsilyl) ethers or diols as comonomers using reducing agent silane and Lewis acid. Moreover, in recent years, it is shown that polyether synthesis and post-polymerization modification (PPM) of polymers proceeds smoothly and effectively with the RER strategy in the presence of chlorodimethylsilane (CDMS), which acts as both a reducing agent and a Lewis acid.  相似文献   
13.
Between 1983 and 1993, 41 patients underwent a first-stage Belt-Fuqua operation for penile hypospadias repair and 39 completed the second stage. Minor complications were observed after the first stage. The primary success rate following the second stage was 82%. Major complications noted after the second stage consisted mainly of fistula formation. The surgical technique is described and alternative methods are discussed.  相似文献   
14.
Mumps is still a common childhood disease in rural areas where mumps vaccination is not widespread. A 14-year-old girl with fatal interstitial nephritis as a complication of mumps is reported. The patient had not been vaccinated with mumps vaccine and had contracted mumps during a village epidemic. The illness began with parotitis, and renal insufficiency developed within a week. The patient’s renal function rapidly deteriorated and the outcome was fatal. The postmortem renal necropsy sample demonstrated interstitial mononuclear cell infiltration, edema, and focal tubular epithelial cell damage, confirming the clinical diagnosis. In developing countries routine mumps vaccination may help to prevent possible fatal complications of mumps. Furthermore, patients with mumps, especially complicated cases, should be followed closely. Received: 19 August 1998 / Revised: 7 December 1998 / Accepted: 8 December 1998  相似文献   
15.
Administration of various doses of 1-(2,5-dimethoxy-4-iodophenyl)-2-aminopropane (DOI) to rats produced dose-related decreases in 1-h food intake in the food-deprived paradigm. Pretreatment with spiperone (5-HT1A/5-HT2/D2 antagonist), propranolol or CGP361A (-adrenoceptor antagonists that also have binding affinities for 5-HT1A and 5-HT1B sites) and MDL-72222 (5-HT3 antagonist) did not attenuate DOI-induced suppression of food intake. In contrast, pretreatment with metergoline (5-HT1/5-HT2 antagonist) completely blocked whereas mesulergine, mianserin and ritanserin (5-HT1C/5-HT2 antagonists) partially blocked DOI's effect on food intake. On the other hand, pretreatment with MDL-72222 but not with m-chlorophenylpiperazine (m-CPP) significantly potentiated DOI-induced suppression of food intake. Furthermore, the food intake suppressant effects of various doses of DOI were found to be similar in the Fawn-Hooded (FH) rat strain as compared to the Wistar rat strain. These findings suggest that DOI-induced suppression of food intake is mediated by stimulation of both 5-HT1C and 5-HT2 receptors.  相似文献   
16.
Monoarticular tuberculosis (TB) affecting the knee is rare in all forms of TB (0.1-0.3%). We present the case of a patient with tuberculous arthritis in whom the diagnosis was belated due to a lack of familiarity with the disease; here, we emphasize the difficulties associated with the diagnosing joint TB. A 20-year-old man was referred to our department due to swelling of the right knee and the presence of persistent, mild pain for 4 years. The lack of systemic evidence of this disease, the indolent course of disease, and the presence of non- specific symptoms renders early recognition of this disease difficult. Furthermore, in cases in which a diagnosis cannot be reached simply by culturing the synovial fluid, synovial biopsy cultures should be considered m the diagnostic process, due to the high rate of positivity of such cultures. The diagnosis and treatment of articular TB are both urgent matters; surgical debridement and strict adherence to antituberculous chemotherapy tend to yield a satisfactory functional outcome.  相似文献   
17.
Endometriosis is defined as the presence of endometrial glands and stroma outside the uterus. Several theories have been proposed to explain the pathogenesis of this disease. According to Sampson's retrograde menstruation theory, endometrial cells are refluxed through the fallopian tubes during the menstruation and implant onto peritoneum or pelvic organs. Since retrograde menstruation is a very common phenomenon among women of reproductive age, there must be other factors that may contribute to the pathophysiology and/or pathogenesis of endometriosis. Genetic predisposition, environmental factors, and alterations in immune and endocrine functions are believed to play significant roles in the establishment and maintenance of endometriosis. Although the eutopic endometriums of women with and without endometriosis are histologically similar, studies revealed that there are many fundamental differences between these two tissues. Invasive properties, decreased apoptosis, alterations in expression of specific gene and proteins, and increased steroid and cytokine production have been identified in eutopic endometrium of women with endometriosis. Furthermore, significant biochemical differences exist even between ectopic and autologous eutopic endometrium. These differences can be explained by the direct effects of an inflammatory peritoneal environment.  相似文献   
18.
Recent years have seen much attention being given to self-assembly of dipeptide-based structures, especially to self-regulation of dipeptide structures with different amino acid sequences. In this study we investigated the effects of varying solvent environments on the self-assembly of glycine-histidine (Gly-His) dipeptide structures. First we determined the morphological properties of Gly-His films formed in different solvent environments with scanning electron microscopy and then structural properties with Fourier-transform infrared (FTIR) spectroscopy. In addition, we studied the effects of Gly-His films on silver nanoparticle (AgNP) formation and the antioxidant and cytotoxic properties of AgNPs obtained in this way. We also, assessed antibacterial activities of Gly-His films against Gram-negative Escherichia coli and Pseudomonas aeruginosa and Gram-positive Staphylococcus aureus. Silver nanoparticle-decorated Gly-His films were not significantly cytotoxic at concentrations below 2 mg/mL but had antibacterial activity. We therefore believe that AgNP-decorated Gly-His films at concentrations below 2 mg/mL can be used safely against bacteria.Key words: Ag, antibacterial surface, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, toxicity  相似文献   
19.
The aim of this study was to assess the rates of variant alleles of cytochrome P4501A1 (CYP1A1) in patients with polycystic ovary syndrome (PCOS). It was designed as a case-control study in Hacettepe University, Faculty of Medicine, Department of Obstetrics and Gynecology and Genetics. Forty-eight patients with PCOS served as the study group. Ninety-six regularly cycling women with no clinical and biochemical evidence of hyperandrogenism and polycystic ovary appearance served as the controls. The CYP1A1 variant alleles of all patients were determined via polymerase chain reaction. The rate of the CYP1A1 isoleucine (Ile)/valine (Val) allele was significantly higher in patients with PCOS than in the controls (OR: 7.8, 95% CI: 3.45-17.52, P < 0.001). However, there was no statistically significant difference in the distribution of Val/Val genotype (OR: 4.0, 95% CI: 0.60-26.73). The rate of any Val genotype (Ile/Val or Val/Val) was significantly higher in patients with PCOS compared with the control group (OR: 7.4, 95% CI: 3.33-16.46, P < 0.001). In conclusion, the patients with PCOS had a 7.8-fold higher frequency of CYP1A1 Ile/Val genotype and a 7.4-fold higher frequency of CYP1A1 of any Val genotype (Ile/Val or Val/Val).  相似文献   
20.
A group of 140 women with a body mass index (BMI) < or = 24 kg/m(2) undergoing 291 cycles was compared with a group of 138 women with a BMI >24 kg/m(2) in 291 cycles, with respect to duration of ovarian stimulation and dose of gonadotrophin, number of oocytes collected, cleavage and implantation rate, clinical pregnancy, miscarriage and delivery rates. Patients with a BMI > 24 kg/m(2) demonstrated a significant decrease in the number of follicles after stimulation (P = 0.01), a comparative increase in the number ampoules of gonadotrophin used (P = 0.03) and a lower number of eggs collected (P = 0.05). The mean number of embryos on days 1, 2 and 3 was significantly lower in the group with BMI > 24 kg/m(2) (P < 0.001). No significant difference was found in clinical pregnancy and miscarriage rates between the two groups. In spite of the lower response in women with BMI > 24 kg/m(2), the delivery rate per retrieval was not different (24.6 versus 24.8%). These results indicate a lower stimulation response in women with elevated BMI, but no adverse effect on IVF outcome. In relation to wellbeing, however, it is recommended that patients with a high BMI reduce their weight before IVF treatment.  相似文献   
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