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71.
CRISPR-Cas 系统的发现彻底改变了基因编辑技术领域,在多方面都有着广阔的前景。该系统主要有Cas 蛋白和单链向导RNA 组成,其功能的发挥高度依赖于各组分的有效递送。本篇综述对目前动植物中该系统组分 的常用递送方式进行详细总结,并分析其目前仍存在的问题。  相似文献   
72.
涎腺导管内癌(intraductal carcinoma,IDC)是一种主要发生在腮腺,在导管内或囊内生长为主的罕见肿瘤,但也可伴浸润性生长,生物学行为相对惰性。具有独特的形态学、免疫表型及分子遗传学特征。主要包括4种亚型:闰管型、顶浆分泌型、闰管-顶浆分泌混合型和嗜酸型。闰管型多数存在NCOA4-RET融合,个别存在STRN-ALK融合;混合型存在TRIM27-RET融合,顶浆分泌型具有PIK3CA和HRAS突变或TP53缺失;嗜酸型具有TRIM33-RET融合或BRAF V600E突变。目前多数观点认为与涎腺导管癌不同,即使存在浸润,仍具有良好的预后,罕见复发和淋巴结转移,无远处转移。因此精准诊断对于临床治疗的选择极其重要。  相似文献   
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Interstitial lung disease (ILD) represents a significant cause of morbidity and mortality in systemic sclerosis (SSc). The purpose of this study was to examine recirculating lymphocytes from SSc patients for potential biomarkers of interstitial lung disease (ILD). Peripheral blood mononuclear cells (PBMCs) were isolated from patients with SSc and healthy controls enrolled in the Vanderbilt University Myositis and Scleroderma Treatment Initiative Center cohort between 9/2017–6/2019. Clinical phenotyping was performed by chart abstraction. Immunophenotyping was performed using both mass cytometry and fluorescence cytometry combined with t-distributed stochastic neighbor embedding analysis and traditional biaxial gating. This study included 34 patients with SSc-ILD, 14 patients without SSc-ILD, and 25 healthy controls. CD21lo/neg cells are significantly increased in SSc-ILD but not in SSc without ILD (15.4 ± 13.3% vs. 5.8 ± 0.9%, p = 0.002) or healthy controls (5.0 ± 0.5%, p < 0.0001). While CD21lo/neg B cells can be identified from a single biaxial gate, tSNE analysis reveals that the biaxial gate is comprised of multiple distinct subsets, all of which are increased in SSc-ILD. CD21lo/neg cells in both healthy controls and SSc-ILD are predominantly tBET positive and do not have intracellular CD21. Immunohistochemistry staining demonstrated that CD21lo/neg B cells diffusely infiltrate the lung parenchyma of an SSc-ILD patient. Additional work is needed to validate this biomarker in larger cohorts and longitudinal studies and to understand the role of these cells in SSc-ILD.

  相似文献   
75.
Lersch  F.  Zingg  T. J. G.  Knapp  J.  Stüber  F.  Hight  D.  Kaiser  H. A. 《Der Anaesthesist》2023,72(9):662-676
Die Anaesthesiologie - Die Elektroenzephalogramm(EEG)-gesteuerte Anästhesie ist aus modernen Operationssälen nicht mehr wegzudenken und hat sich als Standard-Monitoring etabliert. Viele...  相似文献   
76.
Post-induction hypotension is common and associated with postoperative complications. We hypothesised that pneumatic leg compression reduces post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy. In this double-blind randomised study, patients were allocated randomly to the pneumatic leg compression group (n = 50) or control (n = 50). In the intervention group, pneumatic leg compression was initiated before induction of anaesthesia. In the control group, pneumatic leg compression was initiated 20 min after anaesthesia induction. The primary outcome was the incidence of post-induction hypotension in these groups. Post-induction hypotension was defined as systolic blood pressure < 90 mmHg during the first 20 min after induction. Haemodynamic variables and area under the curve of post-induction systolic blood pressure over time were assessed. Complications associated with pneumatic leg compression were recorded, including: peripheral neuropathy; compartment syndrome; extensive bullae beneath the leg sleeves; and pulmonary thromboembolism. The incidence of post-induction hypotension decreased in the pneumatic leg compression group compared with that in the control group; 5 (10%) vs. 29 (58%), respectively, p < 0.001. In the pneumatic leg compression group, the lowest systolic, diastolic and mean blood pressures 20 min after induction of anaesthesia were significantly greater than the control group. Pneumatic leg compression resulted in an increased area under the curve of systolic blood pressure in the first 20 min after induction, p = 0.001. There were no pneumatic leg compression-related complications. Pneumatic leg compression reduced post-induction hypotension in elderly patients undergoing robot-assisted laparoscopic prostatectomy, suggesting that it is an effective and safe intervention to prevent post-induction hypotension among elderly patients undergoing general anaesthesia.  相似文献   
77.
The progress with intensive chemotherapy and supportive care measures has improved survival in patients with newly diagnosed acute myeloid leukemia (AML). Given the recent development of effective low intensity therapies, an optimal decision on the therapy intensity may improve survival through the avoidance of early mortality. We reviewed the outcome of 3728 patients with newly diagnosed AML who received intensive chemotherapy between August 1980 and May 2020. Intensive chemotherapy was defined as a cumulative cytarabine dose ≥ 700 mg/m2 during induction therapy. We divided the whole cohort into a training and validation group at a 3:1 ratio. The population was divided into a training (2790 patients) and a validation cohort (938 patients). The median age was 55 years (range, 15-99). Among them, 442 patients (12%) had core-binding factor AML. Binary logistic regression identified older age, worse performance status, hyperbilirubinemia, elevated creatinine, hyperuricemia, cytogenetic abnormalities other than CBF and -Y, and pneumonia as adverse prognostic factors for an early 4-week mortality. This risk classification for early mortality was verified in the validation cohort of patients. In the validation cohort of more recently treated patients from 2000 to 2017, the 4-week mortality rates with intensive chemotherapy were 2%, 14%, and 50% in the low-, high-, and very high-risk group, respectively. The mortality rates with low intensity therapies were 3%, 9%, and 20%, respectively. The risk classification guides treatment intensity by the assessment of age, frailty, organ dysfunction, cytogenetic abnormality, and infection to avoid early mortality.  相似文献   
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79.
ObjectiveTo evaluate the efficacy and safety of prompt phacoemulsification, intraocular lens implantation, visco-goniosynechialysis, combined with pseudo-pupilloplasty for refractory acute primary angle closure (APAC) with atonic dilated pupil and to describe a feasible method of pupilloplasty.MethodsA consecutive series of refractory APAC patients who had atonic dilated pupil and undergone prompt phacoemulsification combined with pseudo-pupilloplasty at our center were retrospectively analyzed. Pseudo-pupilloplasty referred to a method of pupilloplasty which included 4.5-mm capsulorhexis, postoperative opacification of anterior capsule residue, and ultimate pseudo-pupil formation. Preoperative and postoperative measurements included intraocular pressure (IOP), best corrected visual acuity (BCVA), and anterior chamber depth (ACD). Intraoperative and postoperative complications were documented. The process of pseudo-pupil formation was also observed.ResultsA total of 20 eyes of 19 APAC patients were followed up for 19.7 ± 9.8 months. IOP was lowered from preoperative 44.0 ± 9.8 mmHg to 15.5 ± 2.6 mmHg at final visit (t = 11.945, P < 0.001). ACD was deepened from preoperative 1.77 ± 0.21 mm to 3.40 ± 0.20 mm at final visit (t = –27.711, P < 0.001). Twelve of 20 eyes had residual angle synechiae, whereas only 3 eyes needed anti-glaucoma medications. No severe complication was observed. All eyes had pseudo-pupil gradually formed within 3 months, accompanied with the gradual improvement of BCVA from preoperative 1.18 ± 0.55 to 0.58 ± 0.22, 0.26 ± 0.09, 0.11 ± 0.09, and 0.11 ± 0.09 at postoperative day 1, month 1, month 3, and last visit.ConclusionsPrompt phacoemulsification-goniosynechialysis is effective and safe for refractory APAC with atonic dilated pupil. Pseudo-pupilloplasty is a feasible procedure for pupil reconstruction.  相似文献   
80.
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