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71.
Pheochromocytoma is rarely observed during pregnancy and not easily diagnosed, especially since the clinical manifestations may mimic common gravid hypertension. The maternal and fetal prognosis depends on early diagnosis and multidisciplinary management preparing for tumor resection. Appropriate laboratory tests easily provide the positive diagnosis, if they are ordered. The tumor is localized by ultrasonography or magnetic resonance imaging (MRI). By prescribing an alpha-blocker, it is possible to prepare the resection as a function of term, before or after delivery. This strategy allows a reduction in maternal and fetal mortality which is high if the pheochromocytoma goes undiagnosed.  相似文献   
72.
Aiming to assess the presence of selected anaerobic microorganisms in root canals of human teeth with chronic apical periodontitis. 25 central and lateral upper incisors presenting with radiographic evidence of chronic apical periodontitis were studied. The pulp chamber was opened under aseptic conditions and samples of the root canal content were collected with sterile absorbent paper points, which were placed and dispersed in test tubes containing reduced transport medium RTT. Aliquots were dried on glass slides and stained by indirect immunofluorescence for detection of Actinomyces viscosus, Fusobacterium nucleatum, Porphyromonas gingivalis and Prevotella intermedia. The results showed a positive indirect immunofluorescence reaction in 24 of the 25 samples. Fourteen were positive for the specie Actinomyces viscosus, 12 for Prevotella intermedia, 10 for Fusobacterium nucleatum and 4 for Porphyromonas gingivalis. A semiquantitative assay was easily implemented for assessment of degree of infection by the organisms in individual cases.  相似文献   
73.
The analysis covers 2555 appendectomies, performed on an emergency and scheduled surgery basis in the clinic of emergency surgery.--State University Hospital "Queen Giovanna", Sofia, over the period 1985-1997. Relaparotomy is necessitated in 28 cases (1.09 per cent) because of various postoperative complications. Data are presented on the number of relaparotomies, done under conditions of emergency and scheduled surgery, and with a special reference to the pathoanatomical character of appendicitis. The underlying causes of undertaking relaparotomy and postoperative lethality are analyzed. As shown by the obtained results post-relaparotomy mortality rate is the highest after primary operation for destructive form of appendicitis and advanced form of peritonitis.  相似文献   
74.
OBJECTIVE: To determine the validity and usefulness of a modified Health Assessment Questionnaire (HAQ) for measurement of disease status and changes in disease status over time in patients with systemic sclerosis (SSc). METHODS: Since 1985, 1,250 patients attending the University of Pittsburgh Scleroderma Clinic have completed a modified HAQ annually. In addition to the standard HAQ questions about disability, the questionnaire includes visual analog scales (VAS) to evaluate SSc organ system symptoms, Raynaud's phenomenon, gastrointestinal (GI) tract and lung involvement, pain, and overall disease severity. In this study, the disability index (DI) (from the HAQ) and the VAS scores (on a 0-3 scale) were compared with various clinical and laboratory features recorded within 3 months of administration of the HAQ and VAS, using t-tests and Spearman's correlation tests. RESULTS: The HAQ DI correlated directly with skin involvement, scleroderma heart or kidney disease, tendon friction rubs, hand contractures, and proximal muscle strength. Over time, the DI correlated with changes in skin score and was a good predictor of survival. There was a significant improvement in the DI during a 2-year time period in patients treated with D-penicillamine. The VAS for digital ulcers, GI symptoms, and lung symptoms correlated very closely with subjective and objective findings for these organ systems. The presence of new digital ulcers or improvement in digital ulcers showed significant associations with the Vascular scale, new GI symptoms or improvement in GI symptoms and institution of H2-blockers showed appropriate strong correlations with the GI scale, and changes in the forced vital capacity had an excellent correlation with the Lung scale (r = 0.58, P < 0.001). By Cox regression analysis, the HAQ DI was one of the best predictors of survival. CONCLUSION: These data provide convincing evidence that a self-administered questionnaire is an accurate and inexpensive tool to measure disease status changes in SSc. Prospective studies with the HAQ administered at regular intervals, as in controlled trials, should be performed to further assess the benefits and limitations of this instrument.  相似文献   
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76.
Biodemographic trajectories of longevity   总被引:2,自引:0,他引:2  
Old-age survival has increased substantially since 1950. Death rates decelerate with age for insects, worms, and yeast, as well as humans. This evidence of extended postreproductive survival is puzzling. Three biodemographic insights--concerning the correlation of death rates across age, individual differences in survival chances, and induced alterations in age patterns of fertility and mortality--offer clues and suggest research on the failure of complicated systems, on new demographic equations for evolutionary theory, and on fertility-longevity interactions. Nongenetic changes account for increases in human life-spans to date. Explication of these causes and the genetic license for extended survival, as well as discovery of genes and other survival attributes affecting longevity, will lead to even longer lives.  相似文献   
77.
Lysin is a 16kDa acrosomal protein used by abalone sperm to create a hole in the egg vitelline envelope (VE). The interaction of lysin with the VE is species-selective and is one step in the multistep fertilization process that restricts heterospecific (cross-species) fertilization. For this reason, the evolution of lysin could play a role in establishing prezygotic reproductive isolation between species. Previously, we sequenced sperm lysin cDNAs from seven California abalone species and showed that positive Darwinian selection promotes their divergence. In this paper an additional 13 lysin sequences are presented representing species from Japan, Taiwan, Australia, New Zealand, South Africa, and Europe. The total of 20 sequences represents the most extensive analysis of a fertilization protein to date. The phylogenetic analysis divides the sequences into two major clades, one composed of species from the northern Pacific (California and Japan) and the other composed of species from other parts of the world. Analysis of nucleotide substitution demonstrates that positive selection is a general process in the evolution of this fertilization protein. Analysis of nucleotide and codon usage bias shows that neither parameter can account for the robust data supporting positive selection. The selection pressure responsible for the positive selection on lysin remains unknown.  相似文献   
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79.
The most common form of glomerular disease seen in association with hepatitis C virus (HCV) infection is membranoproliferative glomerulonephritis, with or without associated cryoglobulinemia. This study examines four cases of fibrillary glomerulonephritis and two cases of immunotactoid glomerulopathy in association with HCV infection. Findings at presentation included proteinuria, renal insufficiency, and hematuria. Renal biopsy revealed a membranoproliferative pattern of glomerular disease in five cases, and a membranous glomerulopathy with mesangial proliferative features in one. On immunofluorescence, all cases stained with IgG and C3. Electron microscopy revealed fibrils of the expected diameter, 16 to 28 nm in fibrillary glomerulonephritis and 33 to 45 nm in immunotactoid glomerulopathy. In only one case were cryoglobulins detected (at low titer and on only one of three assays). Antiviral therapy was not given in any of the six cases. Outcomes were mixed, with progression to renal failure occurring in two patients and persistent proteinuria with stable or improved renal function in three. Follow-up is not available on the sixth case. Both fibrillary glomerulonephritis and immunotactoid glomerulopathy have features that overlap with cryoglobulinemic glomerulonephritis. The relatedness of these three entities in a subset of patients with HCV infection suggests a common pathogenic mechanism of glomerular deposition of organized deposits.  相似文献   
80.
The aim of the work was investigation of both efficacy of sulpiride, atypical neuroleptic drug with pronounced antidepressive activity, and its influence on central nervous system. The study was performed in the course of prophylactic treatment of migraine using contingent negative variation (CNV) index. It is demonstrated that sulpiride is effective in prophylactic treatment of migraine complicated with psychologic disorders and autonomic dysfunctions. Such effect may be caused by the drug's influence on depression, anxiety, autonomic symptoms, tension-type headaches. This conclusion was confirmed by CNV data, change of which after sulpiride administration have indicated normalization of mental performance and increase of active adaptive abilities.  相似文献   
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