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991.
Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2, broke out in December 2019 in Wuhan city of China and spread rapidly worldwide. Therefore, by March 2020, the World Health Organization declared the disease a global pandemic. Apart from the respiratory system, various other organs of the human body are also seriously affected by the virus. Liver injury in patients with a severe form of COVID-19 is estimated to be 14.8%-53.0%. Elevated levels of total bilirubin, aspartate aminotransferase and alanine aminotransferase and low levels of serum albumin and prealbumin are the main laboratory findings. Patients with pre-existing chronic liver disease and cirrhosis are much more prone to develop severe liver injury. This literature review presented the recent scientific findings regarding the pathophysiological mechanisms responsible for liver injury in critically ill patients with COVID-19, the various interactions between drugs used to treat the disease and the function of the liver and the specific tests providing the possibility of early diagnosis of severe liver injury in these patients. Moreover, it highlighted the burden that COVID-19 put on health systems worldwide and its effect on transplant programs and the care provided to critically ill patients in general and particularly to those with chronic liver disease.  相似文献   
992.

Background

Non‐small cell lung cancer (NSCLC) is a common malignant tumor. DNA hypermethylation in the promoter region has been served as a potential molecular marker for several tumors. The goal of the current study was to assess the diagnostic ability of mutL homolog 1 (MLH1) promoter methylation in NSCLC.

Methods

A total of 111 NSCLC patients’ paired tissue samples were obtained to explore the association between MLH1 promoter methylation and NSCLC by methylation‐specific polymerase chain reaction (MSP) method. Public databases including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were used to verify our findings.

Results

Our results showed a significantly higher MLH1 methylation frequency in tumor tissue samples than their paired adjacent tissues (= .008). ROC curve indicated that MLH1MSP assay was a sensitive but not a specific method in the diagnosis for NSCLC (sensitivity = 0.964, specificity = 0.135, AUC = 0.550). And the association between the methylation level and clinical characteristics has no statistical significance. TCGA cohort evinced a higher methylation probability in tumor group compared with nontumor group (the mean β value: −0.449 [−0.467, −0.437] vs −0.466 [−0.472, −0.437], = .011), which was consistent with our results. Meanwhile, an inverse correlation between MLH1 methylation and MLH1 expression was detected in TCGA and GEO databases.

Conclusions

The MSP method for MLH1 methylation was a sensitive but not a specific diagnostic method for NSCLC.
  相似文献   
993.
BACKGROUND: The aim of this study was to assess the use of qualitative one-tube nested polymerase chain reaction (PCR) for monitoring the treatment response in smear-positive pulmonary tuberculosis, and the factors determining the negative conversion of sputum smear, culture, and PCR during treatment. METHODOLOGY: A total of 53 patients receiving a standard short course of chemotherapy with 24 months follow-up period after treatment cessation were included in the study. Sputum specimens were collected serially for smear, culture, and PCR until the treatment was complete. RESULTS: The conversion rate for sputum culture, smear, and PCR at 8 weeks after treatment were 84.9, 58.5, and 47.1%, and at 16 weeks of treatment were 100, 88.7, and 79.2%, respectively. At the end of the treatment period, there were four PCR persisters, one of whom had disease relapse. Only cavitary disease had an influence over the negative conversion of the smear and PCR at 8 weeks (RR 3.5, 95% CI 1.04-11.95, P=0.04 for smear; RR 5.06, 95% CI 1.196-21.42, P=0.03 for PCR). CONCLUSION: Qualitative PCR was not useful for monitoring therapy in smear-positive pulmonary tuberculosis. Mycobacterium DNA was cleared slowly in cavitary disease. The PCR may be performed at the time of treatment cessation to identify those with potential for disease relapse.  相似文献   
994.
AIM: To investigate the relationship between the loss of heterozygosity (LOH) of microsatellites on the deleted in colorectal carcinoma (DCC) gene and prognosis of colorectal adenocarcinoma.METHODS: A retrospective study of 58 colorectal adenocarcinoma cases with follow-up data and paired control normal mucosal tissues from 1983 to 1985 from files from the West China University of Medical Sciences Department of Pathology was carried out by PCR microsatellite analysis. Sixteen, 35, and seven cases had well-, moderately, and poorly differentiated tumors, respectively; 11, 30, and 17 cases were staged as Dukes’ A, B, and C, respectively.RESULTS: LOH of DCC microsatellites was detected in 18 cases (31.0%). The 5-year survival rate between LOH-positive and LOH-negative patients was 44.4% and 77.5%, respectively (P < 0.05). The results suggest that LOH of DCC microsatellites correlate with prognosis but not with differentiation (P > 0.05) and Dukes’ stage (P > 0.05) in colorectal adenocarcinoma.CONCLUSION: LOH of DCC microsatellites may be a marker of malignancy. Combined with the traditional prognostic indicators, LOH can predict prognosis of colorectal adenocarcinoma.  相似文献   
995.
996.
目的:调查近期天津市肺炎链球菌下呼吸道感染的耐药情况.方法:对天津市10所医院2000-2002年收治的61例肺炎链球菌所致下呼吸道感染成人患者的细菌培养结果进行回顾性分析,药敏试验采用琼脂纸片扩散法.结果:药敏结果显示,61株肺炎链球菌对青霉素的耐药率为13.1%,头孢噻肟没有耐药菌,其他β-内酰胺类抗生素的耐药率为2.9%~10.0%,红霉素的耐药率为47.1%,左氧氟沙星耐药率为17.8%, 万古霉素没有发现耐药菌.结论:青霉素仍可作为肺炎链球菌所致下呼吸道感染最有效的抗生素,喹诺酮类抗生素耐药率升高应引起高度重视.  相似文献   
997.
宋斌  于忠和  韩文斌 《国际呼吸杂志》2011,31(16):1272-1276
尾加压素Ⅱ最早是从硬骨鱼尾部神经分泌细胞中分离出的环肽,尾加压素Ⅱ受体激活后,通过多种信号传导途径,引起增强心肌收缩、血管收缩、扩张等一系列心血管效应,是迄今已知体内最强的缩血管活性肽。中介素是一种新型血管活性肽,属降钙素基因相关肽家族成员,具有介导心肌收缩,血管舒张,调节细胞增殖、肥大、迁移、凋亡等多种生物学效应,该...  相似文献   
998.
ObjectiveTo report experience with fecal microbiota transplantation (FMT) for recurrent Clostridioides difficile infection (rCDI) and provide recommendations for management of rCDI and donor testing during the COVID-19 pandemic.MethodsA retrospective study of patients with rCDI who underwent FMT from May 26, 2020, to September 30, 2020, with stool from well-screened donors with health and infectious screening and a newly implemented strategy for COVID-19 screening with every 2-week bookend testing with stool quarantine. Patients were followed up for development of rCDI and COVID-19.ResultsOf the 57 patients who underwent FMT for rCDI, 29 were tested for COVID-19 via nasopharyngeal polymerase chain reaction (PCR) and 22 via serology. All results were negative, except for 1 positive serology. Donor testing every 2 weeks for COVID-19 via serology and nasopharyngeal swab PCR was negative, except for 2 donors at 1 center who were excluded. Three patients had rCDI after FMT, and 1 underwent repeat FMT. One patient developed respiratory symptoms suggestive of COVID-19 and tested negative via nasopharyngeal PCR. Eleven patients who underwent COVID-19 testing for elective procedures or hospitalizations tested negative. No SARS-CoV-2 transmission was noted.ConclusionsWith appropriate donor screening, FMT can be performed safely for rCDI during the COVID-19 pandemic. Development of a validated stool assay for SARS-CoV-2 will simplify this process further.  相似文献   
999.
Summary. The accuracy and repeatability of a recently introduced pocket spirometer (Micro Spirometer©; Micro Medical Instruments Ltd, Rochester, UK) was evaluated. FEV] and FVC values obtained with this instrument were compared with those measured with a rolling-seal flow-volume spirometer (CPI220 with microcomputer) in 31 patients and 11 healthy volunteers. In the whole material, expressed as mean ± SD, the pocket spirometer recorded 0.44 ±0.23 1 (13 ±7%) smaller values for FEV1 (P<0.001) and 0.64 + 0.48 1 (15 ± 11%) smaller values for FVC (P<0.001) than the rolling-seal spirometer. The short-term repeatability of the measurements expressed as the coefficient of variation of repeated measurements using the pocket spirometer was 2.2% for FEV1 and 2.3% for FVC in a series of 10 healthy subjects and 10 patients with COPD. It is concluded that the underestimation of FEV1 and FVC of the pocket spirometer was too large and inconsistent for the device to be used interchangeably with conventional spirometers. However, the repeatability of the measurements with the pocket spirometer is close to that reported previously for flow-volume spirometry. Thus the pocket spirometer may be suitable in assessing acute changes of spirometric indices e.g. during provocation tests or during patient follow-up in asthma.  相似文献   
1000.
ObjectiveInterlaminar cervical epidural steroid injections (ICESIs) are commonly used to treat axial neck pain and cervical radicular pain. However, local anesthetics can spread to and block the phrenic nerve and upper segments of the thoracic spinal cord where the sympathetic innervation of the lungs emerges. Therefore, changes in lung function may occur following ICESIs.MethodsThe primary outcome measure was the pulmonary function test (PFT) result 30 minutes before and after ICESI with ropivacaine (0.1875% or 0.25%). The secondary outcome measure was the comparison of the pain scores and functional disability between the two concentrations of ropivacaine 4 weeks after the ICESIs.ResultsFifty patients were randomly assigned to either the R1 (0.1875% ropivacaine) or R2 (0.25% ropivacaine) group. No significant difference was observed between the pre-ICESI and 30-minute post-ICESI PFT results within each group, and no difference was observed between the two groups. After 4 weeks of treatment, both groups showed a significant decrease in pain scores and functional disability; however, no significant differences were observed between the two groups.ConclusionsThis study showed no significant change in lung function after ICESIs in either group and no local anesthetic concentration-based difference in the clinical efficacy of the ICESIs.  相似文献   
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