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991.
Pure red cell aplasia caused by true thymic hyperplasia is extremely rare. We report the case of a 25-year-old female diagnosed with pure red cell aplasia. Following a thymectomy confirming true thymic hyperplasia and corticosteroid therapy, complete response was achieved. Patients diagnosed with pure red cell aplasia should be investigated with a computerized tomographic scan to assess for thymic pathology and if present, this should be resected. Follow-up is essential to monitor for recurrence.  相似文献   
992.
ObjectiveTo explore the analgesic effects and uterine hemodynamics of perpendicular needling (PN) and transverse needling (TN) at SP 6 in patients with primary dysmenorrhea (PD).MethodsIn this randomized controlled trial, patients with PD diagnosed with cold-dampness congealing pattern were randomly assigned in a ratio of 1:1 to receive PN or TN at bilateral SP 6 for 10 min. Acupuncture was performed when the menstrual pain score was over 40 mm on the first day of menstruation, as measured using the visual analog scale for pain (VAS-P). The primary outcome was average menstrual pain (VAS-P). Secondary outcomes included the pulsatility index (PI), resistance index (RI), and systolic-diastolic peaks ratio (S/D) in uterine arteries as measured using color Doppler ultrasonography; anxiety as assessed using the Hamilton Anxiety Rating Scale (HAMA), blood pressure (BP), and heart rate (HR).ResultsForty-eight patients completed the study. The TN group exhibited a significant reduction in VAS-P scores (–5.71 mm, 95% confidence interval (CI): –8.78, –2.63, P = .001), RI values (–0.05, 95% CI: –0.09, –0.01, P = .015), and HAMA values (–2.50, 95% CI: –4.78, –0.22, P = .032) when compared with the PN group. No significant differences in PI, S/D, BP, or HR values were observed between the two groups (P > .05).ConclusionTN at SP 6 was superior to PN in alleviating menstrual pain and anxiety in patients with PD. This analgesic effect of TN may be due to its better ability to improve uterine arterial blood flow via decreases in RI values.  相似文献   
993.
BackgroundThis study investigates in‐hospital mortality amongst patients with severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) and its relation to serum levels of gamma‐glutamyl transferase (GGT).MethodsPatients were stratified according to serum levels of gamma‐glutamyl transferase (GGT) (GGT<50 IU/L or GGT≥50 IU/L).ResultsA total of 802 participants were considered, amongst whom 486 had GGT<50 IU/L and a mean age of 48.1 (16.5) years, whilst 316 had GGT≥50 IU/L and a mean age of 53.8 (14.7) years. The chief sources of SARS‐CoV‐2 transmission were contact (366, 45.7%) and community (320, 40%). Most patients with GGT≥50 IU/L had either pneumonia (247, 78.2%) or acute respiratory distress syndrome (ARDS) (85, 26.9%), whilst those with GGT<50 IU/L had hypertension (141, 29%) or diabetes mellitus (DM) (147, 30.2%). Mortality was higher amongst patients with GGT≥50 IU/L (54, 17.1%) than amongst those with GGT<50 IU/L (29, 5.9%). More patients with GGT≥50 required high (83, 27.6%) or low (104, 34.6%) levels of oxygen, whereas most of those with GGT<50 had no requirement of oxygen (306, 71.2%). Multivariable logistic regression analysis indicated that GGT≥50 IU/L (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.20–3.45, p=0.009), age (OR: 1.05, 95% CI: 1.03–1.07, p<0.001), hypertension (OR: 2.06, 95% CI: 1.19–3.63, p=0.011), methylprednisolone (OR: 2.96, 95% CI: 1.74–5.01, p<0.001) and fever (OR: 2.03, 95% CI: 1.15–3.68, p=0.016) were significant predictors of all‐cause cumulative mortality. A Cox proportional hazards regression model (B = −0.68, SE =0.24, HR =0.51, p = 0.004) showed that patients with GGT<50 IU/L had a 0.51‐times lower risk of all‐cause cumulative mortality than patients with GGT≥50 IU/L.ConclusionHigher levels of serum GGT were found to be an independent predictor of in‐hospital mortality.  相似文献   
994.
995.
The machining of nickel-based super alloys is challenging, owing to the generation of high cutting temperatures, as well as difficulty in maintaining dimensional accuracy and minimizing surface roughness, which compels the use of cutting fluids for reducing these issues due to efficient cooling/lubrication strategies. The present work investigates the comparative performance of four cooling/lubrication techniques: dry cutting, wet, minimum quantity lubricant (MQL) and compressed-air modes in turning Nitronic 60 steel using a new-generation SiAlON ceramic inserts. Several machinability parameters were analyzed for performance evaluation. For this purpose, 16 cycles of turning trials were performed based on Taguchi’s L16 orthogonal array experimental design by varying cutting conditions and lubrication modes. MQL exhibits beneficial effects as compared to the other lubrication conditions concerning low cutting force, improved surface finish, decreased cutting temperature, longer tool life, and lower white layer thickness on machined surface. Burr formation on the saw-tooth chip surface, as well as friction, greatly influenced the tool flank wear due to improper cooling and poor lubrication approach in dry, wet, and compressed-air-cooled machining environments in comparison to MQL-machining. From an economical perspective, the tool life in MQL machining improved by 11%, 72%, and 138% in the comparison with flooded, compressed-air, and dry conditions, respectively. The results of the study demonstrate that using the MQL system can help with heat extraction capability, and provide some promising outcomes.  相似文献   
996.
In this study, compacted hematite (Fe2O3) preforms were made and sintered at various temperatures, such as 1250 °C and 1300 °C, using both conventional and microwave sintering methods. The density, porosity, microhardness, cold crushing strength, microphotographs, and X-ray diffraction (XRD) analysis of the sintered preforms were used to evaluate the performance of the two sintering methods. It was found that microwave sintered preforms possessed lesser porosity and higher density than conventionally sintered preforms owing to uniform heating of the powdered ore in microwave sintering method. Furthermore, it was also observed that microwave sintered preforms exhibited relatively higher cold crushing strength and hardness than conventionally sintered preforms. Thus, the overall results revealed that microwave sintering yielded better properties considered in the present study.  相似文献   
997.
Amides are the most extensively used substances in both synthetic organic and bioorganic chemistry. Unfortunately, the traditional synthesis of amides suffers from some important drawbacks, including low atom efficiency, high catalyst loading, separation of products from the reaction mixture and production of byproducts. Al2O3 is an amphoteric catalyst that activates the carbonyl carbon of the secondary amide group and helps the C–N cleavage of the reactant amide group by attacking the N–H hydrogen. By using the concepts of amphoteric properties of Al2O3, amides were synthesized from secondary amides and amines in the presence of triethylamine solvent. Several aliphatic and aromatic amines were used for the transamidation of N-methylbenzamide in the presence of the Al2O3 catalyst. Moreover, using the Gaussian09 software at the DFT level, HUMO, LUMO and the intrinsic reaction coordinates (IRCs) have also been calculated to find out the transition state of the reaction and energy. In this study, five successful compounds were synthesized by the transamidation of secondary amides with amines using a reusable Al2O3 catalyst. The catalyst was reused several times with no significant loss in its catalytic activity. The products were purified by recrystallization and column chromatography techniques. This catalytic method is effective for the simultaneous activation of the carbonyl group and N–H bond by using the Al2O3 catalyst.

Amides are the most extensively used substances in both synthetic organic and bioorganic chemistry.  相似文献   
998.
Aggressive fibromatosis is proliferation of well‐differentiated fibroblasts. Submandibular region is rare location for fibromatosis. We report a case of a rapidly growing mass in submandibular region of 5‐year‐old girl, excised surgically and ascertained to be aggressive fibromatosis on histological examination. Recovery was uneventful, and she was disease‐free in 6‐month follow‐up.  相似文献   
999.
Whole-genome sequencing (WGS) has played a significant role in understanding the epidemiology and biology of SARS-CoV-2 virus. Here, we investigate the use of SARS-CoV-2 WGS in Southeast and East Asian countries as a genomic surveillance during the COVID-19 pandemic. Nottingham–Indonesia Collaboration for Clinical Research and Training (NICCRAT) initiative has facilitated collaboration between the University of Nottingham and a team in the Research Center for Biotechnology, National Research and Innovation Agency (BRIN), to carry out a small number of SARS-CoV-2 WGS in Indonesia using Oxford Nanopore Technology (ONT). Analyses of SARS- CoV-2 genomes deposited on GISAID reveal the importance of clinical and demographic metadata collection and the importance of open access and data sharing. Lineage and phylogenetic analyses of two periods defined by the Delta variant outbreak reveal that: (1) B.1.466.2 variants were the most predominant in Indonesia before the Delta variant outbreak, having a unique spike gene mutation N439K at more than 98% frequency, (2) Delta variants AY.23 sub-lineage took over after June 2021, and (3) the highest rate of virus transmissions between Indonesia and other countries was through interactions with Singapore and Japan, two neighbouring countries with a high degree of access and travels to and from Indonesia.  相似文献   
1000.
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