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21.
There is a significant body of evidence showing that efficient vaccination schemes against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is helping control the coronavirus disease 2019 (COVID-19) pandemic. However, this goal cannot be achieved without real world data highlighting the impact of vaccines against viral spread. In this study, we have aimed at differentially investigating the impact of COVID-19 vaccines (CoronaVac, Pfizer/BioNTech, Astra/Zeneca Oxford, Janssen) used in North Cyprus in limiting the viral load of Delta and Omicron variants of SARS-COV-2. We have utilized real-time quantitative polymerase chain reaction cycle threshold values (Ct values) as a proxy of viral load of the two SARS-CoV-2 variants. Our results indicate that the administration of at least two doses of the messenger RNA-based Pfizer/BioNTech vaccine leads to the lowest viral load (highest Ct values) obtained for both Omicron and Delta variants. Interestingly, regardless of the vaccine type used, our study revealed that Delta variant produced significantly higher viral loads (lower Ct values) compared with the Omicron variant, where the latter was more commonly associated with younger patients. Viral spread is a crucial factor that can help determine the future of the pandemic. Thus, prioritizing vaccines that will play a role in not only preventing severe disease but also in limiting viral load and spread may contribute to infection control strategies.  相似文献   
22.
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   
23.
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   
24.
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   
25.
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   
26.
Projecting future drug expenditures--2003.   总被引:3,自引:0,他引:3  
Drug expenditure projections for 2003 and factors likely to influence drug costs are discussed. The United States continues to face the challenge of increased growth in health expenditures, and drug expenditures are continuing to increase faster than the growth in total health care expenditures. These increases can be largely attributed to an increase in the average age of the U.S. population and technological advancement. On the basis of price inflation and non-price inflationary factors, including increases in volume, shifts in patient and therapeutic intensity, and expected approval of new drugs, a 10-12% increase in drug expenditures in 2003 for the inpatient setting and a 13.5-15.5% increase for ambulatory care settings are forecasted. While few new drugs are expected to greatly influence expenditures in 2003, the continued diffusion of recently approved drugs such as drotrecogin alfa and nesiritide will have a dramatic impact on total drug expenditures and must be carefully considered in the budgeting process. An agent likely to have a significant impact on HIV treatment is enfuvirtide, the first in a new class of antiretrovirals (fusion inhibitors), but its high cost ($10,000-$15,000 per year) may limit patients' access to this medication. An expanded user's guide is provided to assist the reader in appropriate application of this information in the drug budgeting process. Technological, demographic, and market-based changes and changes in public policy will continue to influence pharmaceutical expenditures in the coming year. An understanding of the overall drivers of medication expenditures and vigilance in monitoring pharmaceutical innovation are critical in the effective management of these resources.  相似文献   
27.
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   
28.
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   
29.
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   
30.
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   
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