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991.
992.
One hundred and eight patients with cystic fibrosis were investigated over one year to determine whether an association existed between rhinovirus or other respiratory virus infection and clinical status. Forced expiratory volume in one second (FEV1), forced vital capacity (FVC), Shwachman score, Chrispin-Norman chest radiograph score, and percentage weight for height were recorded at the beginning and end of the study; days of intravenous antibiotics were noted. Nasopharyngeal aspirates were taken for viral studies during respiratory exacerbations. Serum was collected at enrollment and 2-6 weeks after each respiratory exacerbation. One hundred and fifty seven exacerbations occurred in 76 patients. Respiratory virus infection was detected in 44 exacerbations and rhinovirus was present in 16% (25/157) of exacerbations. Patients with one or more respiratory virus infections were compared with those who had none. When all respiratory virus infections were considered, patients had a significantly greater deterioration in Shwachman score and received significantly more days of intravenous antibiotics. When rhinovirus was considered separately, patients received significantly more days of intravenous antibiotics, but showed no deterioration in clinical status. However, patients infected with another respiratory virus had a significant decline in FEV1, with trends towards significance for decline in FVC and Shwachman score. 相似文献
993.
994.
Camargo Neto EC Schulte J Anele EV Rubim R Lewis E De Mari J Brites A Pires R Giugliani R 《Jornal de pediatria》1998,74(6):447-450
OBJECTIVE: To evaluate the frequency of transient neonatal tyrosinemia, with or without secondary hyperphenylalaninemia,observed through neonatal screening for metabolic disorders, andthe need of monitoration and intervention with drugs and/or specialdiet in selected cases. METHODS: 457.870 dried blood samples obtained by heel stickfrom 3 to 20 days old babies were qualitatively evaluated by aminoacid thin-layer chromatography. Positive cases were quantitativelyconfirmed in serum samples by fluorimetric measurement of tyrosineand phenylalanine. RESULTS: 1.231 dried blood samples displayed positive resultsfor tyrosine in the cromatographic evaluation. The fluorimetricserum analysis disclosed normal levels of tyrosine and phenylalaninein 822 patients. The remained 409 patients showed hightyrosine levels and were placed in three groups according to thetyrosine concentration. In 118 of these cases serum phenylalaninewas also increased. CONCLUCIONS: Transient neonatal tyrosinemia is a very frequentdisorder in neonates (1/372); in some cases very high levels werefound, not only of tyrosine but also phenylalanine. As this findingis not yet accepted as absolutely harmless, the monitoration of thissituation and the use of measures to lower the tyrosine and phenylalaninelevels should be considered by the pediatrician. 相似文献
995.
The clinical course of patients with suspected pulmonary embolism and a negative pulmonary arteriogram 总被引:4,自引:0,他引:4
Novelline RA; Baltarowich OH; Athanasoulis CA; Waltman AC; Greenfield AJ; McKusick KA 《Radiology》1978,126(3):561-567
Selective pulmonary arteriography, with superselective magnification views of the lung bases or other areas where abnormalities are shown on perfusion lung scans, performed within 24-48 hours after the onset of symptoms, can effectively rule out clinically significant pulmonary thromboembolism. One hundred and eighty consecutive patients (minimum follow up, six months) with suspected pulmonary embolism and negative pulmonary arteriograms were studied. Not one of the 167 untreated patients died as a result of thromboembolic disease during the acute illness (20 died from unrelated causes), and none of the 147 patients who survived suffered "recurrent embolism" during follow up. 相似文献
996.
Iwan CC van der Horst Jan Paul Ottervanger Arnoud WJ van 't Hof Stoffer Reiffers Kor Miedema Jan CA Hoorntje Jan-Henk E Dambrink Marcel AT Gosselink Maarten WN Nijsten Harry Suryapranata Menko-Jan de Boer Felix Zijlstra 《BMC medicine》2005,3(1):1-10
Background
Stopping antipsychotic treatment can interrupt improvement and exacerbate the illness. The reasons for discontinuing treatment during controlled clinical trials were analyzed to explore this phenomenon.Methods
A post-hoc, pooled analysis was made of 4 randomized, double-blind clinical trials, 24–28 weeks in duration, involving 1627 patients with schizophrenia or a related disorder. Analyses combined all the atypical antipsychotic treatment groups in the studies.Results
The majority of patients (53%) stopped their treatment at an early stage. Poor psychiatric response along with worsening symptoms was the most frequently given reason for discontinuing the course (36%), which was substantially more common than discontinuation due to poor tolerability of the medication (12%). This phenomenon was corroborated by less improvement in patients who discontinued treatment compared with those who completed, based on the PANSS total scores. Discontinuation due to poor response was, apparently, more predominantly linked to patient perception than to physicians' conclusions alone (80% vs. 20%). Discontinuation due to patient perception of poor response appeared to occur particularly early in the course of treatment. Patients who discontinued due to poor toleration of the medication responded in a more comparable manner with completers.Conclusion
Discontinuing treatment may lead to exacerbation of symptoms, undermining therapeutic progress. In these studies, poor response to treatment and worsening of underlying psychiatric symptoms, and to a lesser extent, intolerability to medication were the primary contributors to treatment being discontinued. Our findings suggest that adherence may be enhanced by effective symptom control, as objectively measured and as subjectively perceived. Such strategies may improve patients' willingness to undertake long-term therapy and increase the likelihood of a better prognosis. 相似文献997.
Mutation rate heterogeneity and the generation of allele diversity at the human minisatellite MS205 (D16S309) 总被引:10,自引:2,他引:10
Many tandemly repeated minisatellite loci display extreme levels of length
variation as a consequence of high rates of spontaneous germline mutation
altering repeat copy number. Direct screening for new allele lengths by
small-pool PCR has shown that instability at the human minisatellite locus
MS205 (D16S309) is largely germline specific and usually results in the
gain or loss of just a few repeat units. Structural analysis of the order
of variant repeats has shown that these events occur preferentially at one
end of the tandem array and can result in complex rearrangements including
the inter-allelic transfer of repeat units. In contrast, putative mutants
recovered from somatic DNA occur at a substantially lower rate and are
simple and non- polar in nature. Germline mutation rates vary considerably
between alleles, consistent with regulation occurring in cis. Although
examination of DNA sequence polymorphisms immediately flanking the
minisatellite reveals no definitive associations with germline mutation
rate variation, differences in rate may be paralleled by changes in
mutation spectrum. These findings help to explain the diversity of MS205
allele structures in modern humans and suggest a common mutation pathway
with some other minisatellites.
相似文献
998.
Aleena Banerji Sunday Clark Michelle Blanda Frank LoVecchio Brian Snyder Carlos A Camargo 《Annals of allergy, asthma & immunology》2008,100(4):327-332
BACKGROUND: Recent data are lacking about the number of patients with angiotensin-converting enzyme inhibitor (ACEI)-induced angioedema who present to the emergency department (ED). Current management of the condition and clinical outcomes also are not known. OBJECTIVE: To describe the clinical epidemiology of ACEI-induced angioedema in patients who present to the ED. METHODS: We performed a medical record review of ACEI-induced angioedema in patients who presented to 5 EDs in the Emergency Medicine Network. A structured data abstraction form was used to collect each patient's demographic factors, medical history, and details about the angioedema that prompted the ED visit. The medical record review also focused on treatment provided in the ED and subsequent need for hospitalization. RESULTS: We identified a total of 220 patients with ACEI-induced angioedema. The frequency of ACEI-induced angioedema among all patients with angioedema who presented to the ED was 30% (95% confidence interval, 26%-34%). The annual rate of visits for ACEI-induced angioedema was 0.7 per 10,000 ED visits. The most frequent presenting signs were shortness of breath, lip and tongue swelling, and laryngeal edema. Most patients (58%) were sent home directly from the ED, whereas 12% were regular inpatient admissions, 11% were admitted to the intensive care unit, and 18% were admitted under observation status (<24 hours). Pharyngeal swelling and respiratory distress were independent predictors of hospital admission and longer length of stay. CONCLUSION: ACEI-induced angioedema accounted for almost one-third of angioedema treated in the ED, although it remains a rare ED presentation. A subgroup of these patients still needs inpatient hospitalization for management of upper airway angioedema. 相似文献
999.
Active immunity and maternally transmitted passive immunity to respiratory syncytial virus (RSV) were studied in cotton rats. Animals infected with respiratory syncytial virus developed complete resistance to pulmonary reinfection, which lasted at least 18 months. Nasal resistance was of shorter duration and began to diminish in 8 months. Pulmonary resistance was transferred by parabiosis, but nasal resistance was not. Adoptive transfer studies with fractionated convalescent blood showed that serum antibody, but not circulating lymphocytes, conferred pulmonary resistance. Immune females conferred antibody to their young prenatally and postnatally, with most of the antibody being transferred via colostrum and milk. Maternally transmitted immunity was more effective in the lungs than in the nose and was transient in both organs. Foster nursing experiments showed colostrum and milk to be the most important routes of immune transfer. Although resistance in infants generally correlated with serum neutralizing antibody levels, several exceptions to this correlation suggested that immune factors other than neutralizing antibody may also play an important role in maternal passive immunity. 相似文献
1000.
Immunodepression Induced by Trypanosoma cruzi and Mouse Hepatitis Virus Type 3 Is Associated with Thymus Apoptosis 下载免费PDF全文
Liana Verinaud Maria Alice Da Cruz-Hfling Júlia K. Sakurada Humberto A. Rangel Jos Vassallo Derek Wakelin Herb F. Sewell Irineu J. B. Camargo 《Clinical and Vaccine Immunology : CVI》1998,5(2):186-191
Trypanosoma cruzi-infected mice show disturbance in the peripheral immune system such as polyclonal lymphocyte activation, autoantibody production, and immunosuppression of T lymphocytes. Previous observations in our laboratory showed that some stocks of T. cruzi can be contaminated with mouse hepatitis virus type 3 (MHV-3). Literature has shown that MHV-3 infection induces immunologic disorders characterized by thymic involution with marked cell depletion. However, the effects of interactions between MHV-3 and the parasite on the immune system are not well understood. In the present study specific-pathogen-free CBA mice were inoculated with MHV-3, alone or associated with different stocks of T. cruzi. Concurrent murine virus infection resulted in increased pathogenicity of T. cruzi infection shown by profound thymic atrophy; loss of cortical thymocytes; depletion of Thy1.2+, CD4+, and CD8+ cells; enhancement of in situ labeling of nuclear DNA fragmentation; and eventually, death of the animals. Such lines of evidence show that the mechanism underlying this thymic atrophy is associated with apoptosis. These results also suggest that MHV-3 can account for the increased immunosuppression observed during experimental infection with the parasite. 相似文献