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951.
Objectives:To compare sedoanalgesia achieved using propofol-fentanyl-ketamine (PFK) combination with general anesthesia (GA) in terms of safety, hemodynamic stability, and perioperative complications.Methods:Patients in the GA group were anesthetized using fentanyl (2 μg kg-1) and propofol (2 mg kg-1). The PFK group was anesthetized using a mixture of which each one ml contains 0.005 mg of fentanyl, 5 mg of propofol, 5 mg of ketamine, and 2 mg of lidocaine. Patients received an initial dose of 0.05 ml kg-1, followed by 0.05 mg kg-1 60 seconds later. Maintenance boluses of 0.025 ml kg-1 were administered every 3-5 minutes. Respiration occurred spontaneously through a simple face mask with 3 L min-1 O2.Results:The GA group had 37 (37%) patients develop hypotensive episodes, compared to one (1%) episode in the PFK group (p<0.001). Five (5%) patients in the PFK group had an episode of transient O2 desaturation, compared to one (1%) patient in the GA group (p=0.212). The duration of induction and termination of anesthesia were significantly shorter in the PFK group (p<0.001).Conclusion:The PFK combination herein described is safe, effective, and provides intraoperative hemodynamic stability in patients with multiple comorbidities undergoing urological procedures.  相似文献   
952.
Background/aim Allergic bronchopulmonary aspergillus (ABPA) is a lung disease caused by hypersensitivity from Aspergillus fumigatus. Diagnostic criteria, staging systems and treatment methods for ABPA disease have been reported in studies evaluating populations, the majority of which are adult patients. Our study aimed to discuss the use of ABPA diagnostic criteria in children, the success of other alternative regimens to oral corticosteroids in the treatment of ABPA, and the changes that occur during treatment, in the light of the literature.Materials and methods Between January 2017 and 2020, patients diagnosed with ABPA at the Dokuz Eylül University Child Allergy and Immunology clinic were identified; demographic characteristics, clinical and laboratory findings, diagnostic scores and stages, and treatment protocols were analyzed retrospectively. Results The mean age of patients diagnosed with ABPA was 14.33 ± 1.96. At the time of ABPA diagnosis, the median total IgE level was 1033 IU/mL (1004–6129), and the median AF specific IgE was 10.64 (2.59–49.70) kU/L. Bronchiectasis was detected in HRCT of 5 cases. We detected significant improvement in spirometric analysis with omalizumab treatment in our patient with steroid-related complications.Conclusion Today, although risk factors have been investigated for ABPA, it has not been revealed clearly. Both diagnostic criteria and treatment regimens have been described in research studies, mostly adults. In pediatric patients; clarification of diagnosis and treatment algorithms is necessary to prevent irreversible lung tissue damage and possible drug side effects.  相似文献   
953.
Due to the COVID-19 infection, which was recognized as a global pandemic by the WHO on March 11, 2020, the number of cases and disease-related deaths increases day by day globally. For this reason, antiviral agents used in treatment and vaccines, the most effective weapon in prevention, continue to be the most popular topic of the plan. Several situations are expected to affect the course of the pandemic. The loss of the ability of the virus to mutate and cause disease, the fact that those who become immunized by having the disease in the society reach a critical rate and create social immunity (herd immunity), and the provision of social immunity with effective vaccination can be counted as some of these situations.Candidate vaccines in the clinical phase among RNA-based vaccines: This review aimed to examine COVID-19 vaccine candidates using RNA technology and compile its current data. We used PubMed, Google Scholar, and World Health Organization (WHO) databases. Also, we followed up on the latest news and developments on vaccine companies’ websites.Conclusion: Vaccination trials, which started due to the seriousness and urgency of the situation that we are in, continue exceptionally quickly and effectively. As per the WHO›s data on July 9, 2021, there have been 291 vaccine trials, 107 of which are in the clinical phase, and 18 (16%) of the vaccine candidates in the clinical phase are RNA-based vaccines. Also, the number of RNA-based vaccines with ongoing preclinical trials is 2  相似文献   
954.
Analysis of IgH and TcR-γ genes using consensus primers identifying junctional regions of rearranged genes by polymerase chain reaction (PCR) was performed on tissues involved by Hodgkin's disease (HD) in 90 cases and was correlated with the immunophenotype of Hodgkin and Reed–Sternberg (HRS) cells and the presence of Epstein–Barr virus (EBV) within these cells. Clonal IgH gene rearrangements were found in 1/5 cases of lymphocyte predominance (LP) subtype and none was positive for EBV. In 85 cases of classic HD, no IgH or TcR-γ gene rearrangements were found in 51 (60 per cent) cases. A similar percentage, but not the same cases, were of null (non-B, non-T) phenotype. Of 30 cases where a B phenotype was assigned to HRS cells, nine had IgH gene rearrangements, three had TcR-γ gene rearrangements, and two had both genes rearranged. None of the five cases assigned to T phenotype of HRS cells showed rearrangement of TcR-γ genes, but two cases showed rearranged IgH genes. Among 41 cases of null phenotype, ten had IgH gene rearrangements, five had TcR-γ gene rearrangements, and three cases had both genes rearranged. Whereas EBV was detectable in HRS cells in 17/43 classic HD cases of assigned B phenotype, EBV was also detectable in 2/5 cases of assigned T phenotype and in 21 cases with the null phenotype. Furthermore, there was no correlation of EBV with the presence or lack of IgH or TCR-γ gene rearrangements. Of the remainder, half (30 per cent) expressed antigens associated with lymphocytes without an appropriate genotype. The results confirm lymphocyte-lineage committed cells at the origin of HRS cells in 40 per cent of cases. Any hypothesis of a non-lymphocytic origin of HRS cells will require the inducibility of CD30 on candidate precursors and the methodology for probing genetic events in such cells to be addressed. © 1997 by John Wiley & Sons, Ltd.  相似文献   
955.
The CAG repeats in the human Huntington's disease (HD) gene exhibit striking length-dependent intergenerational instability, typically small size increases or decreases of one to a few CAGs, but little variation in somatic tissues. In a subset of male transmissions, larger size increases occur to produce extreme HD alleles that display somatic instability and cause juvenile onset of the disorder. Initial efforts to reproduce these features in a mouse model transgenic for HD exon 1 with 48 CAG repeats revealed only mild intergenerational instability ( approximately 2% of meioses). A similar pattern was obtained when this repeat was inserted into exon 1 of the mouse Hdh gene. However, lengthening the repeats in Hdh to 90 and 109 units produced a graded increase in the mutation frequency to >70%, with instability being more evident in female transmissions. No large jumps in CAG length were detected in either male or female transmissions. Instead, size changes were modest increases and decreases, with expansions typically emanating from males and contractions from females. Limited CAG variation in the somatic tissues gave way to marked mosaicism in liver and striatum for the longest repeats in older mice. These results indicate that gametogenesis is the primary source of inherited instability in the Hdh knock-in mouse, as it is in man, but that the underlying repeat length-dependent mechanism, which may or may not be related in the two species, operates at higher CAG numbers. Moreover, the large CAG repeat increases seen in a subset of male HD transmissions are not reproduced in the mouse, suggesting that these arise by a different fundamental mechanism than the small size fluctuations that are frequent during gametogenesis in both species.   相似文献   
956.
A 3 year, 9 month old child with pica presented with a blood lead concentration of 1.74 micromol/l (360 microg/l). The source of poisoning was snooker chalk (lead content 7200 microg/g). She was treated with intravenous calcium disodium edetate chelation. Thirty months later her blood lead was 0.39 micromol/l (80 microg/l). This case illustrates the need to be vigilant for more unusual causes of lead poisoning in the home.  相似文献   
957.
Near‐infrared spectroscopy (NIRS) is a non‐invasive method for monitoring oxygen availability and utilization by the tissues. In intact skeletal muscle, NIRS allows semi‐quantitative measurements of haemoglobin plus myoglobin oxygenation (tissue O2 stores) and the haemoglobin volume. Specialized algorithms allow assessment of the oxidation–reduction (redox) state of the copper moiety (CuA) of mitochondrial cytochrome c oxidase and, with the use of specific tracers, accurate assessment of regional blood flow. NIRS has demonstrated utility for monitoring changes in muscle oxygenation and blood flow during submaximal and maximal exercise and under pathophysiological conditions including cardiovascular disease and sepsis. During work, the extent to which skeletal muscles deoxygenate varies according to the type of muscle, type of exercise and blood flow response. In some instances, a strong concordance is demonstrated between the fall in O2 stores with incremental work and a decrease in CuA oxidation state. Under some pathological conditions, however, the changes in O2 stores and redox state may diverge substantially.  相似文献   
958.
Thrombin is an essential factor in hemostasis, inflammation, and tissue repair. The synthetic thrombin peptide, TP508, binds to high-affinity thrombin receptors and mimics cellular effects of thrombin at sites of tissue injury. Treatment of full-thickness excisional wounds in normal rats with a single topical application of 0.1 microg TP508 (14 pmol/cm2) reproducibly accelerates wound closure, yielding wounds that on average close 39% more than controls by day 7 (p < 0.001). Wounds treated with 1.0 microg TP508 are 35% and 43% (p < 0.001) smaller than controls on day 7 and 10, respectively. The early rate of closure is approximately 40% greater in TP508-treated than vehicle-treated wounds (20 versus 14 mm2/day) and remains higher through day 7. Breaking strength after closure is slightly greater (15-23%) in wounds treated with TP508 than with saline alone. Histologic comparisons show that TP508 enhances recruitment of inflammatory cells to the wound site within 24 hours post-injury. TP508 treatment also augments revascularization of injured tissue, as evidenced at day 7 by the larger size of functional vessels in the granulation tissue and by the directed development of blood vessels to wounds. These studies raise the possibility that TP508 may be clinically useful in management of open wounds.  相似文献   
959.
作者以综述形式论述了肿瘤低氧调节途径的分子生物学基础,并分析了利用低氧调节途径的阻断来治疗肿瘤的几种可行性途径。低氧可导致机体的一系列反应,包括糖酵解、红细胞生成、血管生成、肾上腺素信号传导的改变和血管内皮细胞的增殖等。肿瘤细胞的低氧可导致肿瘤新生血管的形成、浸润性增强、放射敏感性降低、预后变差。而肿瘤细胞又和正常细胞一样,都存在着“氧感应”途径,即低氧通过“血素氧化还原酶”激活氧信号传导系统,导致一系列低氧调节基因的表达。已知的低氧调节基因有:红细胞生成素(EPO)、血管内皮生长因子(VEGF)、糖酵解…  相似文献   
960.
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