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91.
92.
Inflammatory mechanisms, like microglial activation, could be involved in the pathogenesis of Alzheimer's disease (AD). (R)-[11C]PK11195 (1-(2-chlorophenyl)-N-methyl-N-1(1-methylpropyl)-3-isoquinolinecarboxamide), a positron emission tomography (PET) ligand, can be used to quantify microglial activation in vivo. The purpose of this study was to assess whether increased (R)-[11C]PK11195 binding is present in AD and mild cognitive impairment (MCI), currently also known as “prodromal AD.”  相似文献   
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Objective : To describe the symptoms of illness reported by the parents of infants who have died of sudden infant death syndrome (SIDS) compared with those reported by community controls. Methodology : A nationwide case—control study involving regions of New Zealand with 78% of all births between 1987 and 1990. Home interviews were completed with parents of 393 (81% of total) infants who died from SIDS in the post neonatal age group, and 1592 (88.4% of total) controls who were a representative sample of all hospital births in the study region. Results : Symptoms of infection were common in both cases and controls, but were not significantly different. Infants dying of SIDS, however, were likely to have symptoms suggestive of more severe illness in the 2 days before death (odds ratio [OR] = 3.02, 95% confidence interval [CI] 1.69-5.38). After adjusting for potential confounding this was still statistically significant (adjusted OR 2.36, 95% Cl 1.14-4.90). Also, babies dying of SIDS were more likely to have been less reactive to their environment in the 2 weeks before death compared with the controls (univariate OR 0.88, 95% Cl 0.55-1.39, adjusted OR 0.55, 95% Cl 0.59-0.88). ‘Drenching’ sweats at least weekly were reported for 15.6% of case infants compared with 5.9% of control infants (adjusted OR 2.12, 95% Cl 1.53-3.39). Forty per cent of these infants had this symptom in the first 4 weeks of life when it was also associated with a significantly raised risk of SIDS. Apnoea lasting more than 20 s was reported for 13.2% of case infants compared with 5.3% of control infants (adjusted OR 1.93, 95% Cl 1.17-3.17). Similarly, 71.8% of case infants' faces were reported to never turn red while awake compared to 49.8% of control infants (adjusted OR 2.98, 95% Cl 2.19-4.07). Conclusions : Only a small number (6.4%) of babies who die of SIDS have symptoms of serious illness in the 2 days before death. There is support for the hypothesis that there is a group of babies dying of SIDS who have subtle abnormalities in autonomic control or arousal ability.  相似文献   
94.
There are two highly efficacious poliovirus vaccines: Sabin's live-attenuated oral polio vaccine (OPV) and Salk's inactivated polio vaccine (IPV). OPV can be made at low costs per dose and is easily administrated. However, the major drawback is the frequent reversion of the OPV vaccine strains to virulent poliovirus strains which can result in Vaccine Associated Paralytic Poliomyelitis (VAPP) in vaccinees. Furthermore, some OPV revertants with high transmissibility can circulate in the population as circulating Vaccine Derived Polioviruses (cVDPVs). IPV does not convey VAPP and cVDPVs but the high costs per dose and insufficient supply have rendered IPV an unfavorable option for low and middle-income countries.  相似文献   
95.
We investigated whether development of mutations leads to loss of CD8 T-cell recognition in HIV-1 infection and is possibly linked to alterations in HIV-1-specific CD4(+) T-cell responses in 2 HIV-infected individuals. In patient, H434 full genome sequencing of HIV-1 biological clones at early and late time points during disease progression showed development of fixed mutations in 16 predicted HIV-specific CTL epitopes. Loss of T-cell recognition and reactivity against wild-type and mutant epitopes was observed primarily for the HLA-B27-restricted KK10 epitope and HLA-A2-restricted SL9 epitope. Similarly, in patient H671, decreasing numbers of HLA-A3-restricted CD8(+) T cells specific for the wild-type RK9 epitope was observed after CTL escape. Only in patient H434 loss of CTL responses was paralleled by a decrease in HIV-specific IL-2(+) CD4(+) T-helper responses. This suggests that loss of T-cell reactivity may not be directly linked to HIV-specific CD4(+) T-cell responses but that increased viremia after CTL escape may influence CD4(+) T-helper responses.  相似文献   
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98.

Introduction

Prosthetic breast surgery is a very common plastic surgery procedure, but its postoperative analgesic management is a challenge for the surgical team. The purpose of the present study is to validate the analgesic efficacy of pectoral block and serratus plane block in retropectoral mammoplasty.

Patients and methods

A randomised, controlled, triple-blind, clinical trial was designed, and included 30 patients undergoing retropectoral augmentation mammoplasty. All of them had a modified PEC II block and a serratus plane block with a total volume of 40 ml per breast. In 15 of them bupivacaine 0.25% (GPEC) was injected and in the other 15 patients saline was used (GC). Standardised management of anaesthesia and postoperative analgesia was performed. Intra-operative haemodynamic parameters required for postoperative analgesia, and a numeric verbal scale on arrival in the recovery unit were measured and at 3, 6, and 24 h. The quality perceived by patients and surgeons was also measured.

Results

Post-operative pain was significantly better in GPEC (5.3 ± 2.3 vs. 2.9 ± 2.7; P = .018). No significant differences were observed at 3, 6, and 24 h. The surgeons rated the anaesthetic-analgesic quality as very good in 80% of the cases in GPEC versus 33% in CG (P = .01).

Conclusions

The use of these blocks is a good perioperative analgesic strategy in the multimodal management of retropectoral augmentation mammoplasty.  相似文献   
99.

Purpose

This systematic review aims to determine if there are evidence-based recommendations for the optimal mode of delivery for non-cephalic presenting first- and/or second twins. We investigated the impact of the mode of delivery on neonatal outcome for twin deliveries with (1) the first twin (twin A) in non-cephalic presentation, (2) the second (twin B) in non-cephalic presentation and (3) both twins in non-cephalic presentation.

Methods

A computer-aided search of Medline, Embase, Cinahl and Cochrane databases was carried out and quality of the studies was assessed with the Cochrane Collaboration??s tool for assessing risk of bias and the GRADE approach.

Results

One high-quality clinical trial (60 twin pairs) and 16 moderate/low-quality observational studies (3,167 twin pairs) showed no difference in neonatal outcome between vaginal and caesarean delivery in twin A and/or B.

Conclusion

Our results do not suggest benefit of caesarean over vaginal delivery for selected twin gestations with twin A and/or twin B in non-cephalic presentation. However, no final conclusion can be drawn due to the small sample sizes and statistic limitations of the included studies. Randomized studies with sufficient power are required to make a strong recommendation.  相似文献   
100.
We sought to predict neonatal metabolic acidosis at birth using antepartum obstetric characteristics (model 1) and additional characteristics available during labor (model 2). In 5667 laboring women from a multicenter randomized trial that had a high-risk singleton pregnancy in cephalic presentation beyond 36 weeks of gestation, we predicted neonatal metabolic acidosis. Based on literature and clinical reasoning, we selected both antepartum characteristics and characteristics that became available during labor. After univariable analyses, the predictors of the multivariable models were identified by backward stepwise selection in a logistic regression analysis. Model performance was assessed by discrimination and calibration. To correct for potential overfitting, we (internally) validated the models with bootstrapping techniques. Of 5667 neonates born alive, 107 (1.9%) had metabolic acidosis. Antepartum predictors of metabolic acidosis were gestational age, nulliparity, previous cesarean delivery, and maternal diabetes. Additional intrapartum predictors were spontaneous onset of labor and meconium-stained amniotic fluid. Calibration and discrimination were acceptable for both models (c-statistic 0.64 and 0.66, respectively). In women with a high-risk singleton term pregnancy in cephalic presentation, we identified antepartum and intrapartum factors that predict neonatal metabolic acidosis at birth.  相似文献   
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