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51.
52.

Antiphospholipid antibody syndrome (APS) is a systemic autoimmune disorder characterized by venous and/or arterial thrombosis or recurrent fetal loss associated with the presence of antiphospholipid antibodies and/or a lupus anticoagulant. The skin appears to be an important target organ and many cases of APS may present with skin manifestations. These lesions may be manifold and may take the form of livedo reticularis, livedo racemosa, ulcerations, digital gangrene, subungeal splinter hemorrhages, superficial venous thrombosis, thrombocytopenic purpura, pseudovasculitic manifestations, extensive cutaneous necrosis, or primary anetoderma. We report a case of fulminant APS-related cutaneous necrosis. A 38-year-old Caucasian male with a past history of APS, multiple deep vein thrombi/pulmonary emboli, presented with necrotic lesions on his right upper and right lower extremities. Initially, baseline anticoagulation was increased without improvement. Subsequently, plasma exchange was initiated on a daily schedule. Furthermore, rituximab 1,000 mg IV was administered on days 1 and 15. After six consecutive daily sessions of plasma exchange, there was significant regression of the necrotic lesions. After a 22-day hospital stay, the patient was discharged to home on fondaparinux. The patient presented approximately 2 months later after missing follow-up appointments. At the time, his initial lesions looked remarkably improved.

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53.
Group B beta-hemolytic streptococcus (GBS) causes thromboxane (Tx)-associated pulmonary hypertension and hypoxemia in neonatal animals and human infants. The components of GBS that induce these features of sepsis are incompletely characterized. The capsular polysaccharide has been implicated based on the effects of GBS extracts. We used isogenic mutants of a parent GBS strain (COH 31 r/s) devoid of capsular polysaccharide or beta-hemolysin to determine if these components caused the acute features of GBS bacteremia. In neonatal piglets, we observed a similar increase in pulmonary vascular resistance (PVR, mm Hg/L/min) during a 1 h infusion at 5 x 10(8) colony-forming unit/kg/h of COH 31 r/s (n = 5, 11.6 +/- 1.4 to 67.1 +/- 17.9), an isogenic GBS mutant devoid of type III CP (n = 5, 12.5 +/- 1.4 to 56.9 +/- 5.0), and an isogenic GBS mutant devoid of beta-hemolysin (n = 4, 11.0 +/- 1.9 to 51.9 +/- 7.9). All three GBS strains caused increases in blood TxB2 levels, mild arterial hypoxemia, mild reduction in mixed venous PO2, and a 30-40% reduction in cardiac output after a 1 h infusion. The Tx-synthase inhibitor, dazmegrel, completely reversed pulmonary hypertension, and partially reversed arterial hypoxemia and TxB2 levels to baseline values for all GBS strains. In six additional piglets, infusion of polystyrene beads of similar size to GBS at a dose of 5 x 10(8) beads/kg/h caused no changes in gas exchange or blood TxB2 levels, but a mild increase in PVR (13.3 +/- 2.0 to 17.7 +/- 3.5).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
54.
OBJECTIVE: To assess muscoid dipterae species who are able to carry helminth eggs and larvae and to evaluate the potential contamination of trapped dipterae. METHODS: The study was conducted in two different sites of the Zoological Garden of Rio de Janeiro from May 1996 to April 1998. Flies were captured weekly using traps containing putrefied fish, left out in the open for an hour at two sites in the zoo: Site 1 was next to the garbage and Site 2 was near the hippopotamus and birds of prey cages. Of the 41,080 flies captured, Chrysomya megacephala was the most representative species (69.34%), followed by Chrysomya albiceps (11.22%), Musca domestica (7.15%), Chrysomya putoria (4.52%), Fannia sp. ( 3.12%), Ophyra sp. ( 2.53%), and Atherigona orientalis (2.08%). Captured flies had their body surface washed out with distilled water and their gut dissected. RESULTS: Among the species studied, C. megacephala and M. domestica presented higher helminth eggs on their body surface and in their intestinal content. Ascaroidea and Trichinelloidea eggs prevailed in the intestinal content of C. megacephala. The helminth eggs found on the body surface and in the intestinal content were identified as Ascaris sp., Toxascaris sp., Toxocara sp., Trichuris sp., Capillaria sp., Oxyuridae, Trichostrongylidae and Acantocephala. Besides eggs it was also found helminth larvae on the body surface of flies. There were significant differences between the two different capture sites related to the number of helminth eggs found on the flies. CONCLUSIONS: Faeces of zoo animals frequently found in their cages and in the zoo garbage contributed to the proliferation of muscoid dipterans who play an important role in spreading helminth eggs, mainly by direct contact of the flies' body with the animals' food.  相似文献   
55.
As patients with chronic Chagas disease exhibit morphological and functional changes of the stomach (hypomotility and hypochlorhydria), malnutrition, immunological deficiency and high prevalence of peptic disease associated to Helicobacter pylori infection, the purpose of this study was to evaluate if the prevalence of H. pylori infection in chronic chagasic is higher than in non-chagasic individuals in the urban and rural population from Uberlandia, MG, Brazil. Serological determination of IgG antibodies to H. pylori was performed using a second-generation ELISA. Thus, 598 people were evaluated: 128 chagasic (CG), 222 non-chagasic living in urban area (U-NCG) and 248 non-chagasic living in rural area (R-NCG). Regarding the age range from 21 to 50 years, the prevalence of H. pylori infection in the CG (85.1%) was significantly higher than in the U-NCG (56.3%, p < 0.01) and the R-NCG (67.4%, p < 0.05). In the patients over 50 years, the prevalence in the CG (86.4%) was similar to the U-NCG (78.8%) and R-NCG (86.1%). Similar results were also found between the U-NCG and R-NCG for all age ranges, with prevalence rates of 29.1% and 35.3% for the age range from 5 to 13 years, and 47.2% and 40% for that from 14 to 20 years, respectively. We conclude that chagasic patients showed a higher seroprevalence of H. pylori infection than non-chagasic individuals, in the age range from 21 to 50 years, and that the prevalence of this infection was similar in the studied urban and rural non-chagasic population.  相似文献   
56.
57.
Primary jugular foramen meningioma.   总被引:1,自引:0,他引:1  
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58.
Gross and microscopic lesions of the corpus callosum and neighboring structures are common in severe closed head injury. This report is the first, to our knowledge, to confirm neuropathologically the occurrence of extensive traumatic destruction of the corpus callosum in a patient with left-sided apraxia and agraphia. It also demonstrates that large traumatic lesions of the corpus callosum may occur without prolonged posttraumatic coma, vegetative state, or death. In our patient, coexisting extracallosal hemispheric lesions may have modified the effects of callosal pathology. Cases of this type may be more common than generally appreciated, but since symptoms of hemispheric disconnection are not apparent in ordinary behavior, specific tests of callosal function must be employed if disconnection phenomena are to be detected in the posttraumatic period.  相似文献   
59.
The homeostatic function of the colon in acute gastroenteritis   总被引:1,自引:0,他引:1  
R. D. Rubens  H. P. Lambert 《Gut》1972,13(11):915-919
Infants and young children with acute gastroenteritis have been studied with regard to stool electrolyte composition, external electrolyte balance, and aldosterone excretion. At the height of fluid depletion the stool sodium concentrations are low (median 8 m-equiv/1, range 3-58 m-equiv/1). The results indicate that in gastroenteritis the colon is responding homeostatically to a state of secondary hyperaldosteronism, thus assisting in sodium conservation.  相似文献   
60.
OBJECTIVE: To identify the sandfly fauna and some aspects of their behavior in forest and anthropic environments. METHODS: Sandfly captures were undertaken in farm (23 degrees 6' S; 50 degrees 22' W), in Southern Brazil. Falc?o light traps were set in forest, domicile and domestic animal shelters and mosquitoes were collected monthly, between 17h and 7h, from March 1997 to February 1998. RESULTS: A total of 3,655 specimens representing 13 species were captured. Nyssomyia whitmani and Nyssomyia neivai were the predominant species, with a total of 2,977 specimens (81.0%). Of these two species, a total of 2,552 (85.7%) specimens were captured in intradomiciliary and peridomiciliary environments, 2,332 (91.3%) of them in a pigsty. These two species predominated between 20h-21h when 90.4% of the specimens were captured. CONCLUSIONS: Five sandfly species, N. whitmani, N. neivai, Migonemyia migonei, Pintomyia pessoai and Pintomyia fischeri, potential vectors of cutaneous leishmaniasis, were captured. The importance of the two former species is emphasized, since both presented similar behavior in regard to seasonal period, hourly frequency and predominance in the anthropic environment. Besides, N. whitmani was the most predominant species.  相似文献   
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