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41.
Nucleic acid sequence-based amplification (NASBA) was used for detection of the human cytomegalovirus (CMV) immediate early-1 (IE) and the late pp67 mRNA in 353 blood samples collected from 34 liver transplant patients. The diagnostic value of these assays was compared to that of the pp65 antigenemia assay. Overall, 95 and 42% of the antigenemia-positive samples were IE NASBA and pp67 NASBA positive, respectively. Although the results from pp67 NASBA and the antigenemia assay appeared to correspond poorly, a clear correlation was seen between pp67 NASBA-negative results and low numbers of pp65 antigen-positive cells. Twenty patients (59%) were treated with ganciclovir after the diagnosis of symptomatic CMV infection. Before initiation of the antiviral therapy, the antigenemia assay detected the onset of symptomatic infection in all patients, whereas 95 and 60% of these patients were IE NASBA and pp67 NASBA positive, respectively. Although the sensitivity of IE NASBA was very high, the positive predictive value (PPV) of this assay for the onset of a symptomatic infection was only 63%. The PPV of the antigenemia assay as well as pp67 NASBA was considerably higher (80 and 86%, respectively). Thus, the detection of IE mRNA using NASBA appears to be particularly useful as a marker for early initiation of antiviral therapy in patients at high risk for the development of a symptomatic infection. Also, IE NASBA was found to be more sensitive than the antigenemia assay for monitoring CMV infection during antiviral therapy. On the contrary, pp67 NASBA did not appear to have additional diagnostic value compared to the antigenemia assay.  相似文献   
42.
Park MS  Aryan HE  Ozgur BM  Jandial R  Taylor WR 《Neurosurgery》2004,54(3):631-5; discussion 635
OBJECTIVE: We present our experience using a bioabsorbable polymer in the surgical management of one- and two-level degenerative disc disease of the cervical spine with anterior cervical discectomy and fusion. Twenty-six patients were treated at the University of California, San Diego Medical Center or the Veterans Affairs Medical Center in San Diego, CA. All cases were performed under the direction of a single neurosurgeon (WRT). METHODS: A retrospective review of patients' charts and imaging was performed to determine outcomes after anterior cervical spine operations. Specifically, we looked at the need for additional surgery, local reaction to the bioabsorbable polymer, fusion rate, and complications. Procedures involved the C3-C4, C4-C5, C5-C6, and/or C6-C7 levels, and fibular allograft was used in all but one case. The anterior cervical discectomy and fusion procedures with internal fixation were performed in 26 patients between March 2000 and November 2001. The patients were followed for up to 2 years after surgery (average, 14 mo). RESULTS: Radiographic fusion was achieved in 25 (96.2%) of 26 patients. Only one instance of treatment failure was encountered that required additional surgery and the placement of a titanium plate. There were no clinical signs or symptoms of reaction to the bioabsorbable material. CONCLUSION: The rates of fusion after single-level anterior cervical discectomy and fusion with internal fixation using bioabsorbable polymer and screws in this study match those using metallic implants, as previously reported in the literature, and are superior to those achieved with noninstrumented fusions. Preliminary results suggest that this newly available technology for anterior fusion is as effective in single-level disease as traditional titanium plating systems. The bioabsorbable material seems to be tolerated well by patients. A larger, randomized, controlled study is necessary to bring the results to statistical significance.  相似文献   
43.
ObjectiveTo analyze maternal deaths at Nkhoma Church of Central Africa Presbyterian (CCAP) Hospital and identify factors causing delays in care.MethodsMaternal death audits are performed after every maternal death at Nkhoma CCAP Hospital. Information regarding the care provided at the health facility, the referral process, and any delays in the community was collected by an audit team using a structured approach. Data from August 2007 to September 2011 were analyzed retrospectively.ResultsIn total, 61 maternal deaths occurred during the study period, of which 58 were analyzed. Most deaths were categorized as indirect (n = 34 [58.6%]). Non-pregnancy-related infections were the leading cause of indirect death (n = 22), with meningitis the most common (n = 13). Most patients experienced a delay in seeking care (n = 37 [63.8%]), a transport delay (n = 43 [74.1%]), or a delay in receiving adequate care (n = 34 [58.6%]).ConclusionMost maternal deaths had indirect causes and were associated with delays in all phases. An audit makes clear which part of the referral chain needs to be strengthened. Nkhoma CCAP Hospital has taken steps to address all phases of delay.  相似文献   
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Objective

Previous population-based studies suggest that exposure to secondhand smoke (SHS) is related to increased depressive symptoms and poor mental health among non-smokers. We examined whether these associations could be replicated in two independent Dutch samples.

Methods

Non-smoking adults were selected from two studies: 1) the Netherlands Study of Depression and Anxiety (NESDA), comprising individuals with current and remitted depressive and/or anxiety disorders, and healthy controls and 2) the Netherlands Twin Register (NTR), comprising twin-family studies on health-related behaviors. In both studies, SHS exposure was assessed with plasma cotinine levels (1–14 ng/ml vs. < 1 ng/ml). In NESDA, outcomes were current depressive and/or anxiety disorders, and depression and anxiety symptom severity scores. In NTR, the Adult Self Report derived DSM-subscales for depressive and anxiety problems, and anxious depressive scores were analyzed.

Results

In NESDA non-smokers (n = 1757), increased plasma cotinine level (≥ 1 ng/ml) was not related to current depressive and/or anxiety disorders [odds ratio (OR) 0.96, P = .77], nor to depression or anxiety severity indicators. Similarly, in NTR non-smokers (n = 1088) cotinine levels ≥ 1 ng/ml were not associated with the DSM-subscale for depressive problems [unstandardized regression coefficient (B) 0.04, P = .88], nor to other depression and anxiety measures.

Conclusions

In non-smoking adults from patient and population samples, we found no evidence that plasma cotinine levels were related to either depressive and/or anxiety disorders, or to depressive and anxiety symptoms. This suggests that SHS exposure is not related to depression and anxiety in non-smoking adults.  相似文献   
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48.
The purpose of experimental models of traumatic brain injury (TBI) is to reproduce selected aspects of human head injury such as brain edema, contusion or concussion, and functional deficits, among others. As the immature brain may be particularly vulnerable to injury during critical periods of development, and pediatric TBI may cause neurobehavioral deficits, our aim was to develop and characterize as a function of developmental age a model of diffuse TBI (DTBI) with quantifiable functional deficits. We modified a DTBI rat model initially developed by us in adult animals to study the graded response to injury as a function of developmental age - 7-, 14- and 21-day-old rats compared to young adult (3-month-old) animals. Our model caused motor deficits that persisted even after the pups reached adulthood, as well as reduced cognitive performance 2 weeks after injury. Moreover, our model induced prominent edema often seen in pediatric TBI, particularly evident in 7- and 14-day-old animals, as measured by both the wet weight/dry weight method and diffusion-weighted MRI. Blood-brain barrier permeability, as measured by the Evans blue dye technique, peaked at 20 min after trauma in all age groups, with a second peak found only in adult animals at 24 h after injury. Phosphorus MR spectroscopy showed no significant changes in the brain energy metabolism of immature rats with moderate DTBI, in contrast to significant decreases previously identified in adult animals.  相似文献   
49.
Diminished functional lateralization in language-related areas is found in chronic schizophrenia. It is not clear at what stage of illness these abnormalities in lateralization arise, or whether they are affected by medication. In addition, it is hypothesized that reduced language lateralization is related to positive symptoms of schizophrenia, but studies addressing this issue have yielded contradictory results. In this study we used functional MRI to measure language lateralization in 35 first-episode medication-naive schizophrenia patients and 43 matched healthy controls. Subjects performed three language tasks: a paced verb generation task, an antonym generation task, and a semantic decision task. Lateralization Index (LI) was calculated, using a relative threshold technique, in seven Regions of Interest (ROIs), including the main language-related areas and their contralateral homologues. In addition, we investigated whether language lateralization was correlated with psychotic symptoms. Across all ROIs, LI was significantly reduced in patients (p<0.001) compared to controls. Post-hoc tests revealed that this reduction was most prominent in the inferior frontal gyrus (part of Broca's area) (p=0.003) and the superior temporal gyrus (part of Wernicke's area) (p<0.001). LI was not correlated with the positive subscale of the PANSS, nor with hallucinations or disorganization. This is the first study to report reduced LI at the onset of schizophrenia, before medical treatment is initiated.  相似文献   
50.
BACKGROUND: After a first episode of venous thromboembolism, patients are treated with vitamin K (phytonadione) antagonists. There are indications that the risk of recurrence after treatment with vitamin K antagonists decreases relative to the time since the first event. The aim of the present meta-analysis is to describe the risk of recurrent venous thromboembolism after treatment with vitamin K antagonist in relation to the time since the index event. METHODS: Computerized searches in MEDLINE and EMBASE databases; reference checks of pertinent articles; personal communication with colleagues to find randomized clinical trials and cohort studies in which patients with venous thromboembolism were treated with vitamin K antagonists. Per treatment arm, 2 reviewers independently extracted data on the number of recurrent events and the duration of follow-up per time period of 3 months. RESULTS: A total of 135 potentially eligible studies were identified. Of these, 18 studies could be included, comprising 25 treatment arms that could be analyzed. Treatment arms were divided into 3 groups based on treatment duration (short, medium, and long). For all 3 groups, the monthly incidence immediately after discontinuation of treatment was high and declined rapidly thereafter. The monthly incidence after 9 months seemed independent of the treatment duration. CONCLUSIONS: There is a diminishing risk of recurrent venous thromboembolism over time and a stabilization after 9 months independent of the duration of the initial treatment with vitamin K antagonists. These findings have important implications for decision making about the optimal duration of treatment with vitamin K antagonists.  相似文献   
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