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81.
Carla Giordano Alessandro Battagliese Cira R.T. di Gioia Domenico Campagna Flora Benedetti Claudia Travaglini Pietro Gallo Giulia d'' Amati 《Cardiovascular pathology》2004,13(6):317-322
INTRODUCTION: Blue rubber bleb nevus syndrome (BRBNS) is a rare congenital systemic angiodysplasia with multiple vascular malformations in the skin, gastrointestinal tract and, less often, in other internal organs and the brain. CASE REPORT: A 36-year-old man with past history of BRBNS was admitted to our hospital for progressive dyspnea and fatigue. Primary pulmonary hypertension (PPH) was diagnosed. He then developed acute abdominal pain and dyspnea, dying in a few hours due to sudden cardiac arrest. Postmortem examination demonstrated angiomatous lesions located in the skin, small bowel, heart, lungs, liver and thyroid. The lesions were slightly raised, soft and compressible and microscopically consisted of dilated vascular channels lined by a flattened endothelium. The vascular wall was formed by several layers of smooth muscle cells, intermixed with abundant aggregates of elastic lamellae and thin collagen fibers. Luminal thrombi were a frequent finding. In the small bowel, we identified the presence of an abnormally large artery directly opening into a thin-walled venous channel. The most striking finding in the lungs was the presence of thrombi of varying age in the lumen of segmental and elastic arteries, as well as muscular arteries and arterioles. Severe medial hypertrophy of muscular arteries and muscolarization of arterioles were also present. Intimal proliferative lesions and plexiform lesions were never observed. CONCLUSION: The pulmonary findings are consistent with recurrent thromboembolic events from shunts in the visceral lesions. To our knowledge, this is the first report of BRBNS with visceral arterovenous (AV) fistulae complicated by thromboembolic pulmonary hypertension (PH). 相似文献
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83.
Martínez G Ropero C Funes A Flores E Blotta C Landa AI Gargiulo PA 《Physiology & behavior》2002,76(2):219-224
Effect of blocking N-methyl-D-aspartic acid (NMDA) and non-NMDA-glutamatergic receptors on performance in the plus-maze was studied in male rats bilaterally cannulated into the nucleus accumbens (Acc). Rats were divided into seven groups that received either 1 microl injections of saline, (+/-)2-amino-7-phosphonoheptanoic acid (AP-7, 0.2, 0.5, or 1 microg) or 2,3 dioxo-6-nitro-1,2,3,4,tetrahydrobenzo-(f)quinoxaline-7-sulphonamide disodium (NBQX, 0.2, 0.5, or 1 microg) 15 min before testing. Time spent in open arm, time per entry, end arrivals, open, closed, and total arm entries, relationship between open-, closed-, and total arm entries, rearing, face-, head-, and body grooming, and number of fecal boli were recorded. Time spent in the open arm increased under AP-7 (0.5 and 1 microg; P<.01) and NBQX (1 microg; P<.05) treatment, whereas time per entry was increased only with AP-7 (1 microg; P<.05). Open arm entries were increased by the intermediate doses of AP-7 (0.5 microg; P<.01) and NBQX (0.5 microg; P<.05); end arrivals were increased by the intermediate dose of AP-7 (0.5 microg/1 microl, P<.05). The frequency of rearing, grooming, and closed arm entries was not affected by the treatment. We conclude that NMDA and non-NMDA-glutamatergic blockade in the Acc lead to a behavioral disinhibition of cortical influences with the median doses, but that at higher doses the blockers have an anxiolytic-like effect. 相似文献
84.
Elghetany MT Molina CP Patel J Martinez J Schwab H Velagaleti GV 《Cancer Genetics and Cytogenetics》2002,136(1):38-42
Myelodysplastic syndromes (MDS) are associated with cell maturation defects that can manifest as abnormal surface antigen expression. We describe a patient with refractory anemia with excess blasts, who presented with infection and extensive dysplastic features in peripheral blood granulocytes. The granulocytes expressed CD11b, CD13, CD15, CD33, and CD43. The granulocytes also expressed CD4 antigen. Cytogenetic analysis showed a clonal t(5;12)(q33;p13). The patient improved on antibiotics with partial improvement in the dysplastic features. However, shortly after, the patient experienced paravertebral extramedullary blast transformation followed by a leukemia phase of acute monoblastic leukemia. The patient died a few days later. This is the first report describing anomalous expression of CD4 on granulocytes in MDS. Since the breakpoint on chromosome 12 is near the CD4 gene, which is mapped to 12p12, we hypothesize that dysregulation of the CD4 gene may have occurred resulting in its persistent expression on mature and maturing granulocytes. 相似文献
85.
Wolschrijn CF Kik MJ Weijs WA 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,275(1):990-996
The present study describes cartilage-free areas on the ulnar trochlear notch and the humeral condyle of eight very young golden retrievers with otherwise healthy elbow joints. Remarkably, the youngest dog with full-thickness cartilage-free areas was only 8 weeks old. The younger dogs showed no macroscopic abnormalities on the locations that were affected in the older dogs. Two kinds of cartilage modifications were found. Cartilage-free areas at the edges of the articular cartilage layer were present on the humeral capitulum and on two locations of the ulna, (the medial and lateral at the base of the anconeal process, and the trochlear notch near the lateral coronoid process, which was fractured in two cases). Histological examination showed that these cartilage-free areas were filled with dense supportive tissue. Synovial cells covered this tissue as well as the surrounding hyaline cartilage. The synovial membrane covering the areas was macroscopically enlarged, but histological examination revealed no signs of inflammation. The second type of modification consisted of discoloration of the articular surface at the humeral trochlea. Histological examination revealed that in this area the articular surface was composed of fibrocartilage instead of hyaline cartilage. Apparently, there are locations within the elbow joint in which articular cartilage is not necessary for normal joint functioning. The presence of fibrocartilage on the articular surface of the humeral condyle is a surprising finding, for which no explanation has yet been found. 相似文献
86.
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88.
Cleopatra Vasiliu Oprea Claudia Neguleanu Tinca Istroate Cristofor Simionescu 《Macromolecular chemistry and physics.》1975,176(5):1335-1347
Mechano-chemical degradation of poly(ε-caprolactam) {poly[imino(1-oxohexamethylene)]} in the presence of sebacoyl chloride, carried out by vibratory milling, gave polyamide acid chlorides. Subsequently, these products, also by vibratory milling, were condensed with p-phenylenediamine to obtain polymers with aromatic amino groups which by diazotation and coupling reaction were transformed into coloured polymers. The use of some specially selected coupling components (i.e. containing itself primary amino groups) allowed to regulate the colour intensity of the final product when the diazotation and coupling reaction was carried out gradually. 相似文献
89.
Potential sex differences in amplitude, habituation, prepulse inhibition (PPI) and prepulse facilitation (PPF) of the acoustic startle response (ASR) were investigated using male and female mice from the two different inbred mouse strains C57BL/6J (C57) and C3H. Furthermore, the effects of the estrous cycle were tested. The estrous cycle appeared to have no effect on ASR amplitude, habituation, PPF and PPI, the latter being in contrast to results in rats and humans. While sex had no effect on PPI or PPF, males exhibited higher startle amplitudes than females, irrespective of strain, which we discuss to be due to increased male anxiety. In addition, long-term habituation was stronger in C57 males and short-term habituation was weaker in C3H males with respect to females. These results provide evidence for influence of the reproductive hormones on startle reactivity and startle habituation; we therefore conclude that future studies involving genetic influences on behavior using inbred strains are only complete if both sexes are included. 相似文献
90.
Nathalie Thieblemont Laurence Weiss Hoss M. Sadeghi Claudia Estcourt Nicole Haeffner-Cavaillon 《European journal of immunology》1995,25(12):3418-3424
Infection with the human immunodeficiency virus HIV-1 is associated with the expansion of a CD14lowCD16high monocyte subset in peripheral blood. This subset, which represents a minor subpopulation of monocytes in healthy individuals, increases during HIV infection and, in patients with AIDS, may represent up to 40% of the total circulating monocyte cell population. The CD14lowCD16high circulating monocytes co-express MAX.1, p150,95 and HLADR which are typical of tissue macrophage markers. These cells also express higher levels of intracellular interleukin (IL)-1α and tumor necrosis factor (TNF)-α than the CD14highCD16low monocyte population from the same patients. The CD14lowCD16high cells also express low levels of CD35, CD11a and CD4 in common with normal monocytes. When cultured in vitro, monocytes from HIV-seropositive individuals differentiated within a few hours into an elongated fibroblastoid shape characteristic of migratory cells. Our results suggest that the expansion of the CD14lowCD16high monocyte subset, which produce high amounts of TNF-α and IL-1α, may participate in the immune dysfunction observed during HIV infection. 相似文献