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101.
102.
The aims of this study were to investigate the prevalence of hepatitis C virus (HCV) genotypes and serotypes in anti-HCV-positive hemodialysis patients and determine the concordance between genotyping and serotyping methods. Sixty-two hemodialysis patients were included in this study. HCV RNA was determined using polymerase chain reaction assay and genotypes using a line probe assay. HCV serotyping was performed with competitive enzyme-linked immunosorbent assay. Genotype 4 (52 patients) was the most predominant genotype, followed by type 1 (10 patients). The most prevalent HCV serotype was type 4 (41 patients), followed by serotype 1 (6 patients). We detected multiple serotypes in 4 patients and untypeable strains in 11. The overall sensitivity of serotyping assay was 82% for the study patients. According to the genotyping results, the sensitivity of serotyping was 60% and 86.5% for HCV types 1 and 4, respectively. There was a 100% concordance between results of serotyping and genotyping in the identification of HCV type 1 and 91% concordance in HCV type 4. Serological typing method may be of great value in microbiology laboratories that require a simple assay for identification of HCV genotypes, although the sensitivity of this assay may be limited by the immunocompetence of infected hemodialysis patients.  相似文献   
103.

Background

Emergency endotracheal intubation in intensive care is a major challenge that can be associated with life-threatening complications. The aim of this study was to evaluate the success of the first attempt of endotracheal intubation and incidence of complications using Macintosh laryngoscopy, Airtraq or Glidescope during emergency intubation in intensive care.

Patients and methods

One hundred twenty adult intensive care patients of ASA physical status III and IV who required emergency endotracheal intubation were randomly allocated into 3 groups. Group M (40 patients) were intubated using Macintosh laryngoscopy. Group G (40 patients) were intubated using Glidescope. Group A (40 patients) were intubated using Airtraq. The primary outcome was the success of the first attempt of endotracheal intubation. Secondary outcomes included the number of intubation attempts, duration of intubation, glottic view as assessed by Cormack-Lehane grade (C&L grade) and incidence of complications.

Results

Success of the first attempt of endotracheal intubation was significantly higher in both groups G and A compared to group M (p?<?0.05). The number of intubation attempts was significantly higher in group M compared to both groups G and A (p?<?0.05). The duration of endotracheal intubation was 28.80?±?10.27?s in group M compared to 31.45?±?12.17?s in group G and 32.25?±?11.96?s in group A (p?>?0.05). The C&L grade was significantly better in both groups G and A compared to group M (p?<?0.05). No statistically significant difference between the three groups in HR or MAP. The incidence of oxygen desaturation was significantly more in group M compared to groups G and A. No statistically significant difference between the 3 studied groups regarding the incidence of other complications.

Conclusion

Both Glidescope and Airtraq have higher first attempt success rate with a better glottic view and less incidence of oxygen desaturation than Macintosh laryngoscopy during emergency intubation in intensive care.  相似文献   
104.
OBJECTIVE: To determine if screening family members of patients with acute brucellosis will enhance the detection rate of brucellosis and also to determine the relationship between symptoms and brucella serology. MATERIALS AND METHODS: Family members from patients with acute brucellosis were interviewed and serologically screened. All seropositive family members were clinically and serologically followed for six months. RESULTS: Twenty-five acute brucellosis patients and their 178 family members were enrolled from January 2001 to February 2002. Of the 178 family members, 40 (23%) manifested various symptoms, 138 (77%) were asymptomatic, with an overall seroprevalence rate of 34 (19%). The rate of seropositivity among the symptomatic family members was 23 (58%) and for the asymptomatic was 11 (8%) (P<0.001). The majority of the symptomatic family members (13 (57%)) had a high Brucella titer in comparison to one (9%) of the asymptomatic group (P<0.001). Acute brucellosis was diagnosed and treated in 18 (78%) of the symptomatic seropositive family members and in four (36%), of the asymptomatic seropositive family members with an acute brucellosis prevalence rate of 22 (12%). All family members with acute infection recovered without sequelae; one patient relapsed (5%). CONCLUSION: Symptomatic family members are more likely to be seropositive with a high titer in comparison to the asymptomatic members.  相似文献   
105.
106.
107.

Purpose

The purpose of this study was to determine the rate of facial nerve injury (FNI) when performing (ORIF) of mandibular condylar fractures by different surgical approaches.

Materials and methods

A systematic review and meta-analysis were performed that included several databases with specific keywords, a reference search, and a manual search for suitable articles. The inclusion criteria were all clinical trials, with the aim of assessing the rate of facial nerve injuries when (ORIF) of mandibular condylar fractures was performed using different surgical approaches. The main outcome variable was transient facial nerve injury (TFNI) and permanent facial nerve injury (PFNI) according to the fracture levels, namely: condylar head fractures (CHFs), condylar neck fractures (CNFs), and condylar base fractures (CBFs). For studies where there was no delineation between CNFs and CBFs, the fractures were defined as CNFs/CBFs. The dependent variables were the surgical approaches.

Results

A total of 3873 patients enrolled in 96 studies were included in this analysis. TFNI rates reported in the literature were as follows: A) For the transoral approach: a) for strictly intraoral 0.72% (1.3 in CNFs and 0% for CBFs); b) for the transbuccal trocar instrumentation 2.7% (4.2% in CNFs and 0% for CBFs); and c) for endoscopically assisted ORIF 4.2% (5% in CNFs, and 4% in CBFs). B) For low submandibular approach 15.3% (26.1% for CNFs, 11.8% for CBFs, and 13.7% for CNFs/CBFs). C) For the high submandibular/angular subparotid approach with masseter transection 0% in CBFs. D) For the high submandibular/angular transmassetric anteroparotid approach 0% (CNFs and CBFs). E) For the transparotid retromandibular approach a) with nerve facial preparation 14.4% (23.9% in CNFs, 11.8% in CBFs and 13.7% for CNFs/CBFs); b) without facial nerve preparation 19% (24.3% for CNFs and 10.5% for CBFs). F) For retromandibular transmassetric anteroparotid approach 3.4% in CNFs/CBFs. G) For retromandibular transmassetric anteroparotid approach with preauricular extension 2.3% for CNFs/CBFs. H) For preauricular approach a) deep subfascial dissection plane 0% in CHFs b) for subfascial approach using traditional preauricular incision 10% (8.5% in CHFs and 11.5% in CNFs). I) For retroauricular approach 3% for CHFs. PFNI rates reported in the literature were as follows: A) for low submandibular approach 2.2%, B) for retromandibular transparotid approach 1.4%; C) for preauricular approach 0.33%; D) for high submandibular approach 0.3%; E) for deep retroparotid approach 1.5%.

Conclusion

According to published data for CHFs, a retroauricular approach or deep subfascial preauricular approach was the safest to protect the facial nerve. For CNFs, a transmassetric anteroparotid approach with retromandibular and preauricular extension was the safest approach to decrease risk of FNI. For CBFs, high submandibular incisions with either transmassetric anteroparotid approach with retromandibular or transmassetric subparotid approach, followed by intraoral (with or without endoscopic/transbuccal trocar) were the safest approaches with respect to decreased risk of FNI.  相似文献   
108.
The regio- and stereochemical polar [3 + 2] cycloaddition of azomethine ylides, which were generated in situ by the reaction of isatin and sarcosine or benzylamine, with (E)-3-aryl-1-(pyren-1-yl)prop-2-en-1-ones as dipolarophiles, was studied using experimental and theoretical methods. The chemical structures and relative configurations of all products have been fully established by 1D and 2D homonuclear and heteronuclear correlation NMR spectrometry. The effects of the electronic and steric factors of the reactions were discussed. The photophysical properties of the synthesized spiro[indoline-3,2′-pyrrolidin]-2-ones and 5′-phenyl-spiro[indoline-3,2′-pyrrolidin]-2-ones were studied. The mechanism of the reactions was investigated using global and local reactivity indices and frontier molecular orbital (FMO) analysis at the B3LYP/6-31G level of theory. The relationship between the electrophilicity index ω of the dipolarophiles and the Hammett constant σp has been studied. The theoretical scale of reactivity correctly explains the electrophilic activation/deactivation effects promoted by electron-withdrawing and electron-releasing substituents in the para-position of the dipolarophiles.

The regio- and stereochemical polar [3 + 2] cycloaddition of azomethine ylides with (E)-3-aryl-1-(pyren-1-yl)prop-2-en-1-ones as dipolarophiles, was studied using experimental and theoretical methods.  相似文献   
109.
We have updated the dataset of the molecular spectrum of the β-thalassemia (β-thal) in Upper Egypt. Buccal swabs were analyzed from 94 unrelated patients with β-thal major (β-TM) using reverse dot-blot and multiplex amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The most frequent mutation was IVS-I-110 (G>A) (57%). The IVS-I-110, IVS-I-6 (T>C) and IVS-I-1 (G>A) mutations accounted for 87% of the β-thal anomalies. The codon 39 (C>T) and frameshift codon (FSC) 6 (-A) (GAG>-GG) mutations were only detected in Al-Minya and Qina, respectively. We did not observe the IVS-II-745 (C>G) or -101 (C>T) mutations. Forty-three percent of Upper Egyptians were homozygotes. Our efforts were an important step to complete the mutation map of β-thal in Egypt restricted to Cairo and the Nile Delta regions. This study will help to develop preventative programs for Upper Egyptians. It addressed the genetic drift of the β-thal gene mutations in Africa, Asia, and Europe.  相似文献   
110.

Background and objective

Chronic hypoxia induces pulmonary hypertension in mice. Smooth muscle cell hyperplasia and medial thickening characterize the vasculature of these animals. Thrombospondin-1 null (TSP-1-/-) mice spontaneously develop pulmonary smooth muscle cell hyperplasia and medial thickening. In addition, TSP-1 produced by the pulmonary endothelium inhibits pulmonary artery smooth muscle cell growth. Based on these observations we sought to describe the pulmonary vascular changes in TSP-1-/- mice exposed to chronic hypoxia.

Methods

We exposed TSP-1-/- and wild type (WT) mice to a fraction of inspired oxygen (FiO2) of 0.1 for up to six weeks. Pulmonary vascular remodeling was evaluated using tissue morphometrics. Additionally, right ventricle systolic pressures (RVSP) and right ventricular hypertrophy by right ventricle/left ventricle + septum ratios (RV/LV+S) were measured to evaluate pulmonary hypertensive changes. Finally, acute pulmonary vasoconstriction response in both TSP-1-/- and WT mice was evaluated by acute hypoxia and U-46619 (a prostaglandin F2 analog) response.

Results

In hypoxia, TSP-1-/- mice had significantly lower RVSP, RV/LV+S ratios and less pulmonary vascular remodeling when compared to WT mice. TSP-1-/- mice also had significantly lower RVSP in response to acute pulmonary vasoconstriction challenges than their WT counterparts.

Conclusion

TSP-1-/- mice had diminished pulmonary vasoconstriction response and were less responsive to hypoxia-induced pulmonary hypertension than their wild type counterparts. This observation suggests that TSP-1 could play an active role in the pathogenesis of pulmonary hypertension associated with hypoxia.  相似文献   
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