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31.
Cardiopulmonary complications after aneurysmal subarachnoid hemorrhage negatively affect overall morbidity and mortality. An electronic literature search was performed for English-language articles focused on cardiopulmonary complications with subarachnoid hemorrhage published through October 2010. A total of 278 citations were identified, including 72 clinical studies. In most cases, study quality was low or very low. Cardiac injury, evidenced by an elevation in troponin levels, is reported in about one-third of patients after aneurysmal subarachnoid hemorrhage. Arrhythmias also occur in about one-third of patients after subarachnoid hemorrhage. The incidence of pulmonary complications, especially neurogenic pulmonary edema, is more difficult to establish from available literature. Cardiopulmonary complications have been linked to worsened clinical outcome, suggesting a role for cardiac monitoring and interventions.  相似文献   
32.
We have constructed a series of promoter or upstream activating sequence (UAS)-probe plasmids carrying the Tn5-derived neomycin resistance gene whose seven additional ATG codons in the 5-untranslated region were completely or partially removed. When the deleted version of the neo sequence retaining only one additional ATG (NeoD) was expressed under the control of a TDH3 promoter whose UAS was deleted, the transformed cells were unable to grow at a low concentration of the antibiotic G418. In contrast with this, yeast cells expressing the NeoC sequence and having no additional ATG exhibited a high level of G418-resistance. Moreover, the UAS-probe system using NeoD has been successfully applied for the identification of several E. coli DNA sequences that clearly function as UASs in yeast cells. Two of these prokaryotic sequences with UAS activity were identified as a part of the coding region of the tgt and the hydG gene, respectively.  相似文献   
33.
Factors affecting recurrence after incisional hernia repair   总被引:3,自引:0,他引:3  
Incisional hernias occur primarily as a result of high tension and inadequate healing of a previous incision, the latter of which is frequently related to infection at the surgical site. Despite recent advances in operative techniques, the recurrence rate remains unacceptably high. To evaluate the impact of different predisposing factors for the recurrence of incisional hernia, we reviewed retrospectively the medical records of 297 patients who had undergone incisional herniorrhaphy (188 tissue repairs, 109 mesh repairs) in our hospital. Demographic data (age and gender), type of repair, body mass index, hernia size, presence of chronic illnesses and wound complications were evaluated in a univariate and multivariate manner analysis. The overall recurrence rate was 30.3%, with the recurrence rate in patients who underwent tissue repair being 39.4% and that in patients following prosthetic repair 14.6%. The recurrence rate was significantly influenced by type of repair, obesity, hernia size, wound healing disorders and some chronic comorbidities. We conclude that it is necessary to become familar with the risk factors for recurrence of incisional hernia in order to eliminate or decrease their effect on the positive outcome of incisional herniorrhaphy.  相似文献   
34.
The full spectrum of neurologic complications and their impact on survival in lung recipients has not been reported. A retrospective cohort review of the Mayo Clinic Lung Transplant Registry (1988–2008) was performed to determine the range of neurologic complications in a cohort of adult lung recipients. Cox regression models were used to assess risk factors for neurological complications and death posttransplant. One hundred and twenty lung transplant recipients (53% women, median age at transplantation 53 years, range 21–73, median survival 4.8 years) were identified, of whom 95 had a neurological complication posttransplantation (median time to complication 0.8 years). Neurological complications were severe in 46 patients (requiring hospitalization or urgent care and evaluation) and were most often perioperative stroke or encephalopathy. Age predicted neurological complications of any type, whereas lung allocation score, bilateral lung transplantation, sex, underlying lung disease, elevated hemoglobin A1C, renal insufficiency and smoking history did not. Neurological complications of any severity (HR 4.3, 95% CI 2.2–8.6, p < 0.001) and high severity (HR 7.2, 95% CI 3.5–14.6, p < 0.001) were associated with increased risk of death. Neurological complications are common after lung transplantation, affecting 92% of recipients within 10 years. Severe neurologic complications are also common, affecting 53% of recipients within 10 years.  相似文献   
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Neuromuscular complications are not uncommon after bone marrow and stem cell transplantation, especially in patients with allogeneic transplantations and graft-versus-host disease. The pathogenesis of these complications remains unclear, but the changes in immune modulation that occur after transplantation are likely to play a key role. We describe 4 patients who developed brachial plexopathy (3 cases) or multiple lumbosacral radiculopathies (1 case) between 5 days and 4 months after autologous peripheral blood stem cell (3 cases) or allogeneic bone marrow transplantation without evidence of graft-versus-host disease (1 case). Infectious, tumor-related, toxic, and metabolic causes were excluded in all cases. Recovery was limited in two cases and nearly complete in the other two patients. Brachial plexopathies and polyradiculopathies are potential complications of peripheral blood stem cell and bone marrow transplantation. It is possible that these disorders may be the result of autoimmune phenomena directed against specific nerve antigens.  相似文献   
37.
Hippocampal neurons express high levels of HIV chemokine co-receptors, activation of which causes injury or death in vitro. To determine if their in vivo expression correlates with injury, we evaluated neuronal CXCR4 and CCR5 immunoreactivity and reactive gliosis in autopsy hippocampus of 10 control cases, 11 AIDS cases without HIV encephalitis (HIVnE) or opportunistic infections/lymphomas (OI/L), and 11 AIDS cases with HIV encephalitis (HIVE). All groups had higher CXCR4 and CCR5 expression in CA3 and CA4 neurons than CA1 neurons (p < 0.05). HIVE cases had increased neuronal CXCR4 and decreased neuronal CCR5 expression as well as increased numbers of hippocampal GFAP-positive astrocytes and LN3-positive microglia. Changes were most severe in CA3 and CA4 and lowest in CA1 regions. These findings also were noted in the 4 HIVE cases with neither hippocampal HIVE nor brain OI/L and in the HIVnE groups. This study quantitates the regional distribution of hippocampal neuronal CXCR4 and CCR5 and shows their respective increase and decrease in AIDS. It suggests a relationship between neuronal loss and gliosis with intensity of neuronal chemokine expression and raises the possibility of a selective vulnerability of hippocampal neurons to AIDS-related injury.  相似文献   
38.
The black Caribbean population continues to grow in the US and little is known about stroke etiologies in that community. We examined stroke subtypes in 175 consecutive Haitian-born patients living in Miami, admitted for acute stroke. Ischemic stroke was diagnosed in 72%. Small vessel occlusion was the most frequent stroke subtype. There was a high prevalence of hypertension, medication noncompliance and intracranial atherosclerosis. Hypertension was the only cardiovascular risk factor significantly associated with small vessel infarction when compared with non-small vessel infarcts.  相似文献   
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The value of single-photon emission tomography (SPECT) using iodine-123-alpha-methyl-tyrosine (IMT) for the diagnosis of recurrent or residual gliomas is well established. In the current study we investigated whether IMT-SPECT could also be useful in the follow-up of brain metastases and other intracranial tumours of non-astrocytic origin. The study included 22 patients with suspected recurrent intracranial tumours of non-astrocytic origin (12 brain metastases, one supratentorial primitive neuroendocrine tumour (PNET), one rhabdoid tumour, two clivus chordomas, three ependymomas, two pituitary tumours, one anaplastic meningioma) who had previously been treated by surgery and/or radio/chemotherapy. SPECT results were correlated with clinical and MRI follow-up data. The study was true positive in 13 patients, true negative in five, false positive in one and false negative in three patients. Notably, all false negative findings were <13 mm. The resulting sensitivity of the IMT-SPECT was 81%. We concluded that the IMT-SPECT is a promising complementary imaging tool for the detection of recurrences of non-astrocytic intracranial tumours and their distinguishing from treatment-induced changes. The limitation of the IMT-SPECT is its low sensitivity for the detection of small lesions.  相似文献   
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