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81.
Journal of Thrombosis and Thrombolysis - There is no strong evidence on pharmacogenetics role on the quality of INR control after the initiation phase and on the maintenance of stable INR on the...  相似文献   
82.

Background

The Centers for Disease Control and Prevention recommend Tdap immunization during pregnancy, preferably at 27–36 weeks.

Aim

To ascertain whether there is a preferential period of maternal Tdap immunization during pregnancy that provides the highest concentration of pertussis-specific antibodies to the newborn.

Methods

This prospective study measured pertussis-specific antibodies in paired maternal-cord sera of women immunized with Tdap after the 20th week of their pregnancy (n = 61).

Results

The geometric mean concentrations (GMCs) of Immunoglobulin G (IgG) to pertussis toxin (PT) were higher in the newborns’ cord sera when women were immunized at 27–30+6 weeks (n = 21) compared with 31–36 weeks (n = 30) and >36 weeks (n = 7), 46.04 international units/milliliter (IU/mL) (95% CI, 24.29–87.30) vs. 8.69 IU/mL (95% CI, 3.66–20.63) and 21.12 IU/mL (95% CI, 7.93–56.22), p < 0.02, respectively. The umbilical cord GMCs of IgG to filamentous hemagglutinin (FHA) were higher in the newborns’ cord sera when women were immunized at 27–30+6 weeks compared with 31–36 weeks and >36 weeks, 225.86 IU/mL (95% CI, 182.34–279.76) vs. 178.31 IU/mL (95% CI, 134.59–237.03) and 138.03 IU/mL (95% CI, 97.61–195.16), p < 0.02, respectively.

Conclusions

Immunization of pregnant women with Tdap between 27–30+6 weeks was associated with the highest umbilical cord GMCs of IgG to PT and FHA compared with immunization beyond 31 weeks gestation. Further research should be conducted to reaffirm these finding in order to promote an optimal pertussis controlling policy.  相似文献   
83.
ObjectivesWith the increasing severity of the coronavirus disease (COVID-19) pandemic, it is essential that dental health care professionals (DHCPs) are prepared. The study aim was to assess the knowledge, attitudes and practices (KAP) regarding COVID-19 among DHCPs in Saudi Arabia.MethodsA cross-sectional study using a web-based survey was conducted. A validated and reliable questionnaire was developed that comprised 44 questions. Using Qualtrics survey software, DHCPs working in different settings were approached across five geographical regions of Saudi Arabia.ResultsA total of 318 respondents voluntarily participated in the survey. Most DHCPs showed a moderate level of knowledge (51.6%), a positive attitude (92.1%) and adequate practice standards (86.5%). We found that 94.7% of DHCPs had an adequate overall level of KAP. DHCPs with a doctorate significantly outscored DHCPs with other educational levels with respect to knowledge and practice. Older (51–60 years) DHCPs reported significantly more knowledge than younger DHCPs.ConclusionDHCPs displayed an average level of knowledge that needs to be enhanced through continuing education programmes. However, they showed a positive attitude and an acceptable level of practice, as they were abiding by guidelines issued from various international and national health agencies.  相似文献   
84.
Right atrial thrombus can originate from distal venous sources or can be iatrogenic, secondary to the placement of central venous catheters, atrial devices, or surgeries. One of the most common complications of Central Venous Catheters (CVCs) is thromboembolism, which can be either fixed to the right atrium or can be free-floating. Device-related Right Atrial Thrombosis (RAT) can result in catheter occlusion, vascular occlusion, infection, and pulmonary embolism. The true incidence of these complications is unknown because the diagnosis may not be considered in asymptomatic patients, and it might be missed by Transthoracic Echocardiography (TTE). In this literature review, we discuss iatrogenic etiologies of RAT that is complicated by pulmonary embolism. We highlight the importance of maintaining a high index of suspicion of iatrogenic RAT, possible complications, and its management.  相似文献   
85.
Neurocritical Care - The Neurocritical Care Society and the Society of Critical Care Medicine have worked together to create a perspective regarding the Standards of Neurologic Critical Care Units...  相似文献   
86.
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   
87.
OBJECTIVES: We sought to define the incidence of late clinical events and late stent thrombosis in patients treated with drug-eluting (DES) versus bare-metal stents (BMS) after the discontinuation of clopidogrel as well as their timing and outcome. BACKGROUND: There is growing concern that delayed endothelialization after DES implantation may lead to late stent thrombosis and related myocardial infarction (MI) or death. However, event rates and outcomes after clopidogrel discontinuation versus BMS are unknown. METHODS: A consecutive series of 746 nonselected patients with 1,133 stented lesions surviving 6 months without major events were followed for 1 year after the discontinuation of clopidogrel. Patients were assigned randomly 2:1 to DES versus BMS in BASKET (Basel Stent Kosten Effektivit?ts Trial). The primary focus of this observation was cardiac death/MI. RESULTS: Rates of 18-month cardiac death/MI were not different between DES and BMS patients. However, after the discontinuation of clopidogrel (between months 7 and 18), these events occurred in 4.9% after DES versus 1.3% after BMS implantation. Target vessel revascularization remained lower after DES, resulting in similar rates of all clinical events for this time period (DES 9.3%, BMS 7.9%). Documented late stent thrombosis and related death/target vessel MI were twice as frequent after DES versus BMS (2.6% vs. 1.3%). Thrombosis-related events occurred between 15 and 362 days after the discontinuation of clopidogrel, presenting as MI or death in 88%. CONCLUSIONS: After the discontinuation of clopidogrel, the benefit of DES in reducing target vessel revascularization is maintained but has to be balanced against an increase in late cardiac death or nonfatal MI, possibly related to late stent thrombosis.  相似文献   
88.
89.
Effects of TIPS on liver perfusion measured by dynamic CT   总被引:18,自引:0,他引:18  
OBJECTIVE: Our aim was to measure the arterial, portal venous, and total perfusion of the liver parenchyma with dynamic, single-section CT in patients with liver cirrhosis before and after transjugular intrahepatic portosystemic shunt (TIPS) placement and to compare the results with normal values. SUBJECTS AND METHODS: Perfusion of the liver parenchyma was measured in 24 healthy volunteers and 41 patients with liver cirrhosis using dynamic single-section CT. Seventeen patients underwent TIPS placement, and CT measurements were repeated within 7 days. CT scans were obtained at a single level comprising the liver, spleen, aorta, and portal vein. Scans were obtained over a period of 88 sec (one baseline scan followed by 16 scans every 2 sec and eight scans every 7 sec) beginning with the injection of a contrast agent bolus (40 mL at 10 mL/sec). Parenchymal and vascular contrast enhancement was measured with regions of interest, and time-density curves were obtained. These data were processed with a pharmaco-dynamic fitting program (TopFit), and the arterial and portal venous component and the total perfusion of the hepatic parenchyma were calculated (milliliters of perfusion per minute per 100 mL of tissue). RESULTS: Mean normal values for hepatic arterial, portal venous, and total perfusion were 20, 102, and 122 mL/min per 100 mL, respectively. In patients with cirrhosis before TIPS, mean hepatic arterial, portal venous, and total perfusion was 28, 63, and 91 mL/min per 100 mL, respectively, which was statistically significant for all values (p <0.05). After TIPS, hepatic perfusion increased to a mean value of 48, 65, 113 mL/min per 100 mL for arterial (p <0.01), portal venous, and total (p=0.011) perfusion, respectively. CONCLUSION: In patients with cirrhosis, the hepatic arterial perfusion increased, whereas portal venous and total perfusion decreased compared with that of healthy volunteers. TIPS placement caused a statistically significant increase of the hepatic arterial and total hepatic perfusion. The portal venous parenchymal perfusion remained unchanged.  相似文献   
90.
We used 31P and 13C solid-state nuclear magnetic resonance (NMR) spectroscopy to detect and analyze the major organic and inorganic components (collagen type I and bioapatite) in natural rabbit bone and β-tricalcium phosphate implants loaded with osteogenically differentiated mesenchymal stem cells. High-resolution solid-state NMR spectra were obtained using the magic-angle spinning (MAS) technique. The 31P NMR spectra of bone specimens showed a single line characteristic of bone calcium phosphate. 13C cross-polarization (CP) MAS NMR spectra of bone exhibited the characteristic signatures of collagen type I with good resolution for all major amino acids in collagen. Quantitative measurements of 13C-1H dipolar couplings indicated that the collagen segments are very rigid, undergoing only small amplitude fluctuations with correlation times in the nanosecond range. In contrast, directly polarized 13C MAS NMR spectra of rabbit bone were dominated by signals of highly mobile triglycerides. These quantitative investigations of natural bone may provide the basis for a quality control of various osteoinductive bone substitutes. We studied the formation of extracellular bone matrix in artificial mesenchymal stem cell-loaded β-tricalcium phosphate matrices that were implanted into the femoral condyle of rabbits. The NMR spectra of these bone grafts were acquired 3 months after implantation. In the 31P NMR spectra, β-tricalcium phosphate and bone calcium phosphate could be distinguished quantitatively, allowing recording of the formation of the natural bone matrix. Further, 13C CPMAS allowed detection of collagen type I that had been produced in the implants. Comparison with the spectroscopic data from natural bone allowed assessment of the quality of the bone substitute material. J. S. and M. P. contributed equally to this study  相似文献   
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