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排序方式: 共有472条查询结果,搜索用时 15 毫秒
91.
Nocardia infection in the acquired immunodeficiency syndrome 总被引:2,自引:0,他引:2
E E Telzak J Hii B Polsky T E Kiehn D Armstrong 《Diagnostic microbiology and infectious disease》1989,12(6):517-519
A case of Nocardia asteroides pneumonia in a patient with the acquired immunodeficiency syndrome who was intolerant of sulfadiazine is described. On cefuroxime, the patient had a complete resolution of his Nocardia pneumonia. Disk-diffusion and broth microdilution antibiotic susceptibility testing (MIC less than or equal to 2 micrograms/ml) strongly supported the use of cefuroxime as treatment in this patient. Susceptibility testing with newer cephalosporins should be considered for all significant Nocardia isolates. 相似文献
92.
A plasma fibronectin-rich component was prepared by heparin-induced 4 degrees C precipitation of fresh or stored (21 days at 4 degrees C), single-donor plasma. The recovery of plasma fibronectin was 45 percent at a concentration of 0.05 mg heparin per ml (7.5 units/ml) and 75 percent at 0.1 mg per ml (15 units/ml). The biologic activity of plasma fibronectin, as assessed by the spreading of Chinese hamster ovary cells or attachment of monocytes to gelatin-coated surfaces, was similar to that of plasma fibronectin concentrates made from fresh or stored plasma. Only 20 to 30 percent of the factor VIII activity in fresh plasma was recovered in cryoprecipitate produced after the heparin-induced precipitate containing fibronectin was removed. Cryoprecipitate prepared from the supernatant plasma that remains after heparin-induced cold precipitation in the presence of CaCl2 (5 mM) contained approximately 50 percent less factor VIII. The relatively low recovery of factor VIII in cryoprecipitate prepared from fibronectin-depleted plasma makes cryoprecipitation an unsuitable method of producing fibronectin-rich and factor VIII-rich components effectively from a single unit of fresh plasma. However, heparin-induced cold precipitation provides an efficient method for preparing plasma fibronectin concentrates from small plasma pools or single units of stored or fresh plasma. 相似文献
93.
Background
Studies show that tuberculosis notification declines with increasing altitude. This can be due to declining incidence or declining case detection. In Vietnam notification rates of new smear-positive tuberculosis in the central mountainous provinces (26/100,000 population) are considerably lower than in Vietnam in general (69/100,000 population). In order to clarify whether this is explained by low incidence or low case detection, we aimed to assess the prevalence of new smear-positive tuberculosis among adults with prolonged cough in three mountainous provinces in central Vietnam. 相似文献94.
Masood R; Zhang Y; Bond MW; Scadden DT; Moudgil T; Law RE; Kaplan MH; Jung B; Espina BM; Lunardi-Iskandar Y 《Blood》1995,85(12):3423-3430
Interleukin-10 (IL-10) is an acid-sensitive protein of 35 kD that has pleiotropic effects including inhibition of cytotoxic T-cell response, induction of major histocompatibility complex type II in B lymphocytes, induction of B-cell growth and differentiation, and autocrine growth factor activity in monocytes. We and others have shown that IL-10 is produced spontaneously by blood mononuclear cells from human immunodeficiency virus-seropositive patients. In an attempt to ascertain the potential role of IL-10 in acquired immunodeficiency syndrome (AIDS)-related B-cell lymphoma, we evaluated the expression of human IL-10 in both tumor-derived B-cell lines and primary tumor cells. Expression of human IL-10 (hIL-10) mRNA and protein was detected in four of five cell lines examined. An IL-10 antisense oligonucleotide inhibited IL-10 mRNA expression and IL-10 protein production. The proliferation of all B-cell lines was inhibited by an antisense oligonucleotide in a dose-dependent manner that was abrogated by the addition of recombinant hIL-10 protein. No effect of antisense oligonucleotide was observed in the B-cell line not producing hIL-10. Evaluation of primary tumor cells from patients with AIDS-lymphoma cells showed similar production and response to IL-10. These data suggest an autocrine growth mechanism for IL-10 in AIDS-related lymphoma cells and that IL-10 may be important in its pathogenesis. 相似文献
95.
Bone mineral density at distal forearm can identify patients with osteoporosis at spine or femoral neck 总被引:1,自引:0,他引:1
Forearm bone mineral density (BMD) was investigated in women to identify
osteoporosis at the spine or femoral neck (or both) defined by WHO criteria
(T score -2.5) without requirement for fracture. BMD was measured by
single-energy X-ray absorptiometry (DTX100) and by dual- energy X-ray
absorptiometry (DXA) in the lumbar spine and femoral neck in 422 subjects
aged 22-90 yr. A total of 62% of subjects with osteoporosis (at the spine,
femoral neck, or both sites) were detected with 89% specificity [receiver
operating characteristics (ROC) analysis] and included all subjects below
forearm BMD 0.34 g/cm2. Conversely, above 0.419 g/cm2, only 10% of patients
had osteoporosis. A total of 71.8% of women could be assigned either to
those who warranted therapy (<0.34 g/cm2) or to those who did not
(>0.419 g/cm2) with 90% certainty. Subjects with forearm BMD between
0.34 and 0.419 g/cm2, who constituted 28.2% of the total group and included
31% of subjects with osteoporosis, had a 40% chance of having osteoporosis.
This leads to a high identification rate on subsequent DXA scanning, which
is thus used efficiently.
相似文献
96.
Dale DC; Bonilla MA; Davis MW; Nakanishi AM; Hammond WP; Kurtzberg J; Wang W; Jakubowski A; Winton E; Lalezari P 《Blood》1993,81(10):2496-2502
Patients with idiopathic, cyclic, and congenital neutropenia have recurrent severe bacterial infections. One hundred twenty-three patients with recurrent infections and severe chronic neutropenia (absolute neutrophil count < 0.5 x 10(9)/L) due to these diseases were enrolled in this multicenter phase III trial. They were randomized to either immediately beginning recombinant human granulocyte colony- stimulating factor (filgrastim) (3.45 to 11.50 micrograms/kg/d, subcutaneously) or entering a 4-month observation period followed by filgrastim administration. Blood neutrophil counts, bone marrow (BM) cell histology, and incidence and duration of infection-related events were monitored. Of the 123 patients enrolled, 120 received filgrastim. On therapy, 108 patients had a median absolute neutrophil count of > or = 1.5 x 10(9)/L. Examination of BM aspirates showed increased proportions of maturing neutrophils. Infection-related events were significantly decreased (P < .05) with approximately 50% reduction in the incidence and duration of infection-related events and almost 70% reduction in duration of antibiotic use. Asymptomatic splenic enlargement occurred frequently; adverse events frequently reported were bone pain, headache, and rash, which were generally mild and easily manageable. These data indicate that treatment of patients with severe chronic neutropenia with filgrastim results in a stimulation of BM production and maturation of neutrophils, an increase in circulating neutrophils, and a reduction in infection-related events. 相似文献
97.
Blood cells participate in the fibrinolytic response to tissue-type plasminogen activator 总被引:1,自引:0,他引:1
Exercise and venous occlusion stimulate fibrinolysis. In addition to increased concentrations of tissue-type plasminogen activator (tPA) and increased plasmin-mediated fibrinolysis in plasma, these stimuli produce additional cellular-phase activity in blood that is of the same magnitude as the plasma response. To determine whether tPA alone, rather than other consequences of these stimuli, is responsible for the cellular response, the in vitro effects of tPA on whole blood, plasma, and calculated cellular-phase (whole blood minus plasma) activities were determined by solid-phase radiofibrin assay on venous blood from ten normal subjects (seven men, three women). At tPA concentrations encompassing physiological and therapeutic levels (5 to 100 ng/mL; 0.7 to 14 IU/mL), increments in whole blood were consistently in excess of those in companion plasma and represented increased cellular-phase activity equivalent in magnitude to the well-known increase in plasma activity. Fibrinolytic activity produced by 10 to 20 ng tPA/mL (1.4 to 2.8 IU/mL) was consistently detected in whole blood and plasma by 60 minutes, with higher concentrations (100 ng or 14 IU tPA/mL) detectable after a five-minute assay in all subjects. Thus, tPA alone, without invoking fibrinolytic factors extraneous to blood or other effects of exercise or venous occlusion, accounts for both cellular and plasma responses to these stimuli. The considerable cellular response, the mechanism of which remains to be elucidated, may constitute a determinant of individual therapeutic responsiveness to tPA. 相似文献
98.
HK Ulatowska G Streit Olness MW Keebler KE Goins 《International journal of speech-language pathology》2013,15(1):3-14
This investigation explores the discourse devices associated with high-quality personal narratives. The study examined normative characteristics of 11 high-quality personal narratives of a frightening experience identified (from a larger set of 72 narratives) for their effectiveness in engaging the audience. Lay ratings and an ethnographic interview with seven of the excellent storytellers further characterized the stories and validated their selection. Narratives of both African Americans and Caucasians were represented, and were similar in nature. The excellent narratives were longer, conveyed more fearful topics, and were more dramatic than average narratives. Drama was achieved through direct speech, prosodic shifts, voice changes, inclusion of multiple characters, repetition, and syntactic and semantic parallelism. Illustrative narrative excerpts are provided. This study illustrates the potential in pairing holistic and analytical approaches to narrative analysis. 相似文献
99.
100.
We describe a 5 1/2 year old boy who was diagnosed with mild autosomal recessive osteopetrosis based on the presence of bony sclerosis, extramedullary haematopoeisis, leukoerythroblastosis and visual impairment who had an allogeneic bone marrow transplant from a matched sibling donor. Conditioning regime was busulphan 16 mg/kg and cyclophosphamide 200 mg/kg. Apart from transient hypercalcaemia, there were no major post transplant complications. Four years post transplant, the extramedullary haematopoeisis has resolved completely with normal blood counts. Apart from a fracture after a trivial fall two months after transplant, he has not suffered any fracture related limb deformities. 相似文献