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991.
992.
The impact of early prophylactic use of intravenous indomethacin on the incidence and severity of periventricular-intraventricular hemorrhage and patent ductus arteriosus in 199 oxygen-requiring premature infants (less than or equal to 1300 g birth weight) was prospectively investigated. The trial was controlled, the infants were randomized, and the investigators were unaware of the group assignments. Patients with minimal (grade I) or no periventricular-intraventricular hemorrhage determined by prestudy echoencephalography were randomized within two birth weight subgroups (500 to 899 and 900 to 1300 g) to receive either prophylactic indomethacin (n = 99) or an equal volume of saline-vehicle placebo (n = 100). The first dose (0.2 mg/kg) was given within 12 hours of delivery and two subsequent doses (0.1 mg/kg) were administered at 12 hourly intervals. Prophylactic indomethacin significantly reduced the incidence of grades II to IV periventricular-intraventricular hemorrhage. Intraventricular hemorrhage was half as common in infants given prophylactic indomethacin as in control infants (23% v 46%, P less than .002). The reduction was manifested in both birth weight subgroups. Results of this study also confirmed a lower incidence of clinically significant patent ductus arteriosus in infants who received prophylactic indomethacin in contrast to those who received placebo (11% v 42%, P less than .001). No significant differences were found between treatment and control groups in the duration of oxygen therapy, mechanical ventilation, or hospitalization or in the incidence of pneumothorax, chronic lung disease, sepsis, necrotizing enterocolitis, retinopathy of prematurity, or death. Early prophylactic indomethacin initiated within 12 hours of delivery is effective in reducing the incidence of intraventricular hemorrhage as well as clinically significant patent ductus arteriosus in very low birth weight premature infants.  相似文献   
993.
994.
995.
Factors Influencing Surgical Complications of Intra-Axial Brain Tumours   总被引:3,自引:0,他引:3  
Summary  Object. Extensive surgical resection remains nowadays the best treatment available for most intra-axial brain tumours. However, postoperative sequelae can outweigh the potential benefits of surgery. The goal of this study has been to review the results of this treatment in our Department in order to quantify morbidity and mortality and determine predictive risk factors for each patient.  Method. We report a retrospective study of 200 patients submitted to a craniotomy for intra-axial brain tumours including gliomas and metastases. Postoperative major complications are analysed and related to different variables. An exhaustive review of the literature concerning the main controversial points about primary and metastatic brain tumours surgery is done.  Findings. The overall major complication rate was 27.5%, with neurological complications being the most frequently encountered. We did not find a statistically significant relation between them and the grade of eloquence of the tumoural area. Infratentorial tumour location, previous radiotherapy and reoperations were factors strongly related to the incidence of regional complications. Age over 60 and severe concomitant disease were risk factors for systemic complications.  Interpretation. The results from published series concerning surgical complications after craniotomies for brain tumours are not comparable because of the lack of homogeneity between them. The knowledge of the complications rate in each particular neurosurgical department turns out essentially to provide the patient with tailored information about risks before surgery.  相似文献   
996.
Clinical management of the patient with pleural effusion   总被引:1,自引:0,他引:1  
Pleural effusion is a frequent medical problem with a wide span of different causes. We wish to highlight the clinical management of the patient with pleural effusions but anatomic, physiologic and diagnostic management of the main pleural diseases will also be considered.  相似文献   
997.
Electron microscopy (EM) is a valuable standard tool in basic research and teaching. However, its use in diagnosis is limited, either for strategic reasons or budgetary constraints. This means that its many potential applications are more often neglected, either as an ancillary tool, quality control method, or gold standard, to complement, support, or confirm results of pathological studies. To evaluate the use of EM in this setting, the authors analyzed all articles (n = 2,531) in the three top indexed diagnostic pathology journals for a period of 60 months from July 1993 to June 1998. A total of 448 articles in which the use of EM was indicated, according to standard surgical pathology textbooks, were selected. Both the actual and the potential EM content of each article were scored, as follows: zero, illustrative, supportive, gold standard (for confirmation of research results), extensive, and predominant. Of the total number of articles in which EM was indicated, 77% made use of the technique. EM support was lacking most frequently in articles on serosal neoplasms and on new diagnostic strategies (p < .00005). There was no definite trend toward an increase or decrease in the use of EM during the period analyzed. The authors conclude that EM is used in most reports on diagnostic pathology, when it is indicated. However, a small but non-negligible percentage of articles (23%) could benefit from including EM as an ancillary, control, or gold standard method to complement, support, or confirm their results.  相似文献   
998.
Cytofluorograph analysis after immunofluorescence with monoclonal antibodies can be useful for various antigens identification on the surface of cell membrane. This technic is described for antigen HLA B27 identification. This HLA antigen is known indeed to be linked to rhumatismal diseases. The fluorescence histograms obtained, allow to differentiate easily subjects which have HLA B27 phenotype and subjects which are HLA cross linked.  相似文献   
999.
The authors recently reexamined the peripheral nerve biopsies from 42 patients with chronic inflammatory demyelinating polyneuropathy (CIDP). There were 27 males and 15 females, aged from 9 to 84 years, and 13 had relapses. No patient had vasculitis, monoclonal gammopathy, tumor, diabetes mellitus, Lyme disease, familial neuropathy, HIV, or any other immune deficiency. In the endoneurium, perivascular inflammatory cell infiltrates were present in only one case, but scattered histiocytes marked by KP1 on paraffin-embedded fragments were present in every case and there were no T-lymphocytes. At ultrastructural examination macrophage-associated demyelination was observed in 17 cases, of which 6 had relapses separated by intervals of several months or years. Axonal lesions without associated primary demyelination were observed in 4 cases and 3 of these had relapses. Thirty-two patients had mixed lesions of demyelination and axonal involvement. This study confirms other recent data indicating that in all cases of CIDP, macrophages are present in the endoneurium. Macrophage-associated demyelination is the characteristic feature of demyelinating forms. On the other hand, isolated primary axonal forms, which have been known since 1989, are relatively frequent and prone to relapses.  相似文献   
1000.
A double transgenic mouse expressing the amyloid precursor protein, bearing the Swedish mutations, and expressing tau protein containing three of the mutations present in frontotemporal dementia linked to chromosome 17 (FTDP-17), has been characterized. In the double transgenic mouse an increase in tau phosphorylation at serine S262 and S422 was observed compared with that found in simple transgenic mice. The phosphorylation at S262 was also found, in a much lower level, in the single transgenic mouse expressing amyloid precursor protein (APP), and it was absent in that overexpressing tau variant. Additionally, in the double transgenic mouse a slight increase in the amount of sarkosyl insoluble tau polymers was observed in comparison with that found in single transgenic tau mouse. Also, wider tau filaments were found in the double transgenic mouse compared with those found in the single transgenic mouse. Our results suggest that beta-amyloid peptide could facilitate the phosphorylation of tau at a site not directed by proline, such as serine 262, and that modification could facilitate tau aberrant aggregation. Also, they suggest that different types of tau filamentous polymers can occur in different mouse models for tauopathies, like those used for Alzheimer's disease or FTDP-17.  相似文献   
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