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3-Diazo-2-phenylpyrroles 3a-g showed antimicrobial activity against Gram-positive bacteria, whereas against Gram-negative strains the inhibitory activity is limited to derivatives 3a and 3c. The substituents at 4 and 5 positions strongly influence the inhibitory activity, but the presence of the diazo group is crucial for appearance of activity.  相似文献   
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Summary Spontaneous circadian variations of prostate specific antigen (PSA) and prostatic acid phosphatase (PAP), determined simultaneously by radioimmunoassay (RIA), were investigated by multiple sampling, over a 24-hour period, in 32 patients with prostatic cancer. In 29/32 patients (91%), the coefficient of variation of 24-hour values, for either marker, was greater than that of the RIA method at the same range of values; stage D patients showed the greatest spontaneous variability. Fluctuations around the mean of 24-hour values ranged from-65% to +85% for PAP, from-72% to +190% for PSA, occurring random and independently for each marker. Variability was about 20% greater for PSA than for PAP. The existence of spontaneous fluctuations should be considered in multiple marker evaluation of prostatic cancer patients.Preliminary results of this study have been presented at the International Symposium on Hormonal Therapy of Prostatic Diseases —Basic and Clinical Aspects, April 6–8, 1987, Milan, Italy  相似文献   
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Summary In Wilson's disease neurological manifestations result from the damage in the basal ganglia, even if a widespread degeneration of the brain occurs. The few studies performed using evoked potentials with the aim of identifying subclinical dysfunction in the three major sensory pathways have never shown abnormalities in patients without neurological manifestations. To verify this observation we studied 12 patients suffering from Wilson's disease in a pre-neurological stage by using pattern visual evoked potentials (VEPs), somatosensory evoked potentials (SEPs) to median nerve stimulation and brainstem auditory evoked potentials (BAEPs). Four of these patients had not yet been treated with penicillamine or trientine (triethylenetetramine dihydrochloride), while the remaining 8 patients were on treatment for at least 1 year. In 3 patients of this second group and in 1 patient of the first group we observed a significant (3 SD over the mean) increase in P100 wave latency, while SEPs and BAEPs were found to be abnormal in only 1 patient, respectively.  相似文献   
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H R Massie  V R Aiello 《Gerontology》1992,38(1-2):13-17
The lead content of mouse femurs increased by 83% between 76 and 958 days of age with values ranging from 0.192 to 1.78 ng Pb/mg dry weight. These values are remarkably lower than in previous reports for the lead content of bone. The lead content of mouse liver showed no aging-related trend with values ranging from 0.00823 to 0.0149 ng/mg dry weight. Bone density, calcium and collagen content were not related to the lead content. We conclude that while bone lead content is very low in mice, it increases with aging but does not appear to be related to the osteopenia which develops in the C57BL/6J male mouse.  相似文献   
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Crosslineage T-cell receptor delta (TCR delta) rearrangements are widely used as tumor markers for the follow up of minimal residual disease in childhood B-precursor acute lymphoblastic leukemia (ALL) by polymerase chain reaction (PCR). The major drawback of this approach is the risk of false-negative results due to clonal evolution. We investigated the stability of V delta 2D delta 3 rearrangements in a group of 56 childhood B-precursor ALL patients by PCR and Southern blot analysis. At the PCR level, V delta 2D delta 3-to-J alpha rearranged subclones (one pathway for secondary TCR delta recombination) were demonstrated in 85.2% of V delta 2D delta 3-positive patients tested, which showed that small subclones are present in the large majority of patients despite apparently monoclonal TCR delta Southern blot patterns. Sequence analysis of V delta 2D delta 3J alpha rearrangements showed a biased J alpha gene usage, with HAPO5 and J alpha F in 26 of 32 and 6 of 32 clones, respectively. Comparison of V delta 2D delta 3 rearrangement status between diagnosis and first relapse showed differences in seven of eight patients studied. In contrast, from first relapse onward, no clonal changes were observed in six patients studied. To investigate the occurrence of crosslineage TCR delta rearrangements in normal B and T cells, fluorescence-activated cell sorter-sorted peripheral blood CD19+/CD3- and CD19-/CD3+ cell populations from three healthy donors were analyzed. V delta 2D delta 3 rearrangements were detected at low frequencies in both B and T cells, which suggests that V delta 2-to-D delta 3 joining also occurs during normal B-cell differentiation. A model for crosslineage TCR delta rearrangements in B-precursor ALL is deduced that explains the observed clonal changes between diagnosis and relapse and is compatible with multistep leukemogenesis of B-precursor ALL.  相似文献   
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A bstract Eight patients (4 men, 4 women), mean age 51 years, referred to our Institution for left atrial myxoma underwent removal of the tumor through a superior transseptal approach. All patients in sinus rhythm with normal conduction time. The myxomas were localized in the fossa ovalis (3 cases), interatrial septum (2 cases), left appendage (2 cases), and mitral annulus (1 case). One patient died in hospital after emergency operation for low-output syndrome complicated by septic shock. All other patients had an uneventful postoperative course. Atrial arrhythmias did not represent a major postoperative complication. Transient PR interval elongation was occasionally seen. Electrophysiological studies showed normal sinus node function. At 6 months following operation, patients were evaluated with transeso-phageal echocardiography. There was no tumor recurrence. There were no episodes of arrhythmia in 24-hour electrocardiographic monitoring, and all patients were in NYHA Class I. We believe that the superior transseptal approach gives optimal exposure of the left atrial cavity, overcoming all difficulties related to a small left atrium which is an usual pattern in left atrial myxomas.  相似文献   
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