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971.
Since 1987, about 60 cases of porphyria cutanea tarda (PCT) associated with human immunodeficiency virus (HIV) have been reported. The respective roles of HIV and toxic hepatic factor in PCT remain unclear. We report 10 new cases and analyse the following toxic hepatic factors: hepatitis C and B, alcoholism, drugs. The route of HIV transmission to these 10 men were: IV drugs abuse (3), homo/bisexuality (4), heterosexuality (1), and unknown (2). When PCT was diagnosed, their average age was 38 years (29-54) and the HIV-infection had been established for 4.8 years (0.33-9). Seven men had HIV-related symptoms and a CD4+ lymphocyte count below 200/mm3. Cutaneous signs and urinary porphyrin count were characteristic. Alcohol abuse was present in 8/10 patients. AST, ALT and/or gamma GT were high in 9/10 patients; 5/10 patients had HCV antibodies (4 were HCV-PCR positive). HBs antigenemia was negative among the 5/8 patients with HBV antibodies; 10/10 patients took prescribed hepatotoxic drugs. Our series confirms the presence of toxic hepatic factors in PCT of HIV-positive patients. Hepatitis C, alcoholism and hepatotoxic drug consumption seem to be triggers for the appearance of PCT in HIV-positive patients. 相似文献
972.
Although the importance of the father for the development of the child is well known and although an increased presence of the father in the family system is often demanded, processes of active shutting out the father occur. The deterioration of relation between father and child is not seen as a result of pathological male personality, but rather as a result of family or couple system. The special situation for counsellors of such cases is discussed. 相似文献
973.
LE Hernandez PJ Connelly SA Strickler MM Akers MM Dunn 《Canadian Metallurgical Quarterly》1994,116(4):610-4; discussion 614-5
BACKGROUND: Stereotaxic core breast biopsy (SCBB) has been proposed as a cost-effective and reliable method of evaluating mammographic lesions. This study evaluates an initial experience with SCBB and assesses the adequacy of the biopsy specimens obtained. METHODS: Two hundred forty-one SCBB were performed on 221 patients during 13 months by four radiologists. Mammograms were assigned a suspicion index on a scale of 1 to 5. One pathologist performed a blinded retrospective review of all SCBB specimens and assigned an adequacy score based on the quality and amount of the tissue present. RESULTS: The majority of SCBB were ordered by general surgeons (67%). A suspicion index score of 3 was assigned to 74% of lesion specimens. Twelve percent of specimens were malignant. Overall SCBB adequacy (score > or = 2) was 77%. Adequacy was present in 74% of benign biopsy specimens as compared with 100% of malignant specimens (p < 0.005). Only 62% of specimens reported as benign without specific features were adequate. There were no differences in adequacy between individual radiologists or during the study period. CONCLUSIONS: SCBB is largely used by surgeons to assess indeterminate mammographic lesions. One of four benign specimens was inadequate. Benign SCBB specimens must be interpreted with caution. 相似文献
974.
SW Knight T Vulliamy GL Forni D Oscier PJ Mason I Dokal 《Canadian Metallurgical Quarterly》1996,33(12):993-995
Dyskeratosis congenita (DC) is characterised by reticulate skin pigmentation, mucosal leucoplakia, and nail dystrophy. Bone marrow failure occurs in 50% of patients and is the principal cause of early mortality. In the majority of families the pattern of inheritance of DC is compatible with an X linked recessive trait. The locus for the X linked recessive form of DC has been linked to Xq28. We have now extended our earlier studies by investigating five families with additional Xq28 polymorphic markers; analysis of recombination events in these families has located the DC1 locus between GABRA3 and DXS1108, an interval of approximately 4 Mb. 相似文献
975.
In a 82-year-old woman varicella zoster encephalitis was diagnosed, a rare complication of shingles. The case was remarkable for its rapid and fatal course in a patient without an underlying disease. At autopsy, the histological picture of an acute haemorrhagic encephalitis was seen, also a rare finding. 相似文献
976.
MJ Marino ST Rouse AI Levey LT Potter PJ Conn 《Canadian Metallurgical Quarterly》1998,95(19):11465-11470
Evidence suggests that cholinergic input to the hippocampus plays an important role in learning and memory and that degeneration of cholinergic terminals in the hippocampus may contribute to the memory loss associated with Alzheimer's disease. One of the more prominent effects of cholinergic agonists on hippocampal physiology is the potentiation of N-methyl-D-aspartate (NMDA)-receptor currents by muscarinic agonists. Here, we employ traditional pharmacological reagents as well as m1-toxin, an m1 antagonist with unprecedented selectivity, to demonstrate that this potentiation of NMDA-receptor currents in hippocampal CA1 pyramidal cells is mediated by the genetically defined m1 muscarinic receptor. Furthermore, we demonstrate the colocalization of the m1 muscarinic receptor and the NR1a NMDA receptor subunit at the electron microscopic level, indicating a spatial relationship that would allow for physiological interactions between these two receptors. This work demonstrates that the m1-muscarinic receptor gene product modulates excitatory synaptic transmission, and it has important implications in the study of learning and memory as well as the design of drugs to treat neurodegenerative diseases such as Alzheimer's. 相似文献
977.
We report a case of carbamazepine-induced hypersensitivity syndrome with prolonged fever, rash, pharyngitis, mild cholestasis and renal impairment which resolved within 2 weeks after stopping carbamazepine. Prominent eosinophilia developed after improvement of clinical signs. 相似文献
978.
We routinely use a variety of real time signal acquisition, enhancement, and display techniques in the operating room to provide the surgeon with functional information. This enables reduction of surgical morbidity in cases which present a significant risk to the nervous system. Here we present regression based signal processing algorithms which produce considerable signal-to-noise-ratio enhancement with corresponding reduction in the time required to obtain an interpretable neurophysiological signal. We also present the approach we have applied to fault tolerance and distributed data display for our workstation cluster environment. 相似文献
979.
Selective ET(A) receptor antagonism reduces neointimal hyperplasia in a porcine coronary stent model
CJ McKenna SE Burke TJ Opgenorth RJ Padley LJ Camrud AR Camrud J Johnson PJ Carlson A Lerman DR Holmes RS Schwartz 《Canadian Metallurgical Quarterly》1998,97(25):2551-2556
BACKGROUND: As endothelin binds to ET(A) receptors, it stimulates vascular smooth muscle cell proliferation and may thus be pivotally involved in the pathogenesis of restenosis. This study assessed the ability of a potent and selective ET(A) antagonist to reduce neointimal hyperplasia in a porcine coronary artery stented injury model. METHODS AND RESULTS: Fifty-five pigs were randomized to receive placebo or the oral ET(A)-selective antagonist ABT147627 twice daily for 28 days in one of three doses: 0.75 mg/kg (low), 3.75 mg/kg (mid), and 10.0 mg/kg (high). Each underwent oversized stent deployment in two randomly assigned major epicardial coronary arteries. Three animals (5.5%) died as a consequence of stent thrombosis within 24 hours of the procedure. The remaining 52 animals (13 pigs per group) survived without complication until predetermined euthanasia at 28 days. In the placebo group, mean injury score was 1.73+/-0.80, with a mean neointimal response of 0.45+/-0.24 mm. By comparison, the low-dose group had a similar mean injury score of 1.79+/-0.75 with reduced neointimal response, 0.36+/-0.22 mm (P<0.01). Mean injury score in the mid-dose animals was significantly greater than in the placebo group (1.94+/-0.92; P<0.05). The neointimal hyperplasia associated with this injury was less than with placebo, although the difference did not reach statistical significance (0.40+/-0.25 mm; P=0.05). In the high-dose pigs, mean injury score was also significantly greater than in the placebo arm (1.93+/-0.73; P<0.05). Despite this, neointimal response was also significantly less (0.37+/-0.37 mm; P<0.01). CONCLUSIONS: Oral, selective ET(A) receptor antagonism significantly reduced neointimal hyperplasia forming over porcine coronary stented injuries in the first 28 days. This strategy may have clinical potential for the limitation and treatment of coronary restenosis after percutaneous revascularization. 相似文献
980.
PJ Jenks 《Canadian Metallurgical Quarterly》1998,317(7172):1568-1571