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101.
Marrow stromal layers were used to investigate the potential role of negative regulators produced by the marrow microenvironment as one potential cause of hematopoietic suppression after chemotherapy and cytokines. Stromal layers were established from marrow of normal or prechemotherapy donors and breast cancer patients after hematological recovery from one cycle of 5-fluorouracil, leucovorin, doxorubicin, and cyclophosphamide and GM-CSF or PIXY321 (GM-CSF/IL-3 fusion protein). Normal donor CD34+ cells were placed in contact with stromal layers, and the number of colony-forming units for granulocytes and macrophages (CFU-GM) was determined. There were 25-79% fewer CFU-GM in post-chemotherapy stromal layer cocultures than in no chemotherapy cocultures. With neutralizing antibody to TNF-alpha the number of CFU-GM in no chemotherapy and post-chemotherapy stromal cocultures was, respectively, 96 +/- 7% (n = 5) and 142 +/- 8% (n = 5) of the number with no antibody treatment. PIXY321 and GM-CSF pretreated stromal layers also suppressed production of CFU-GM. Anti-TNF-alpha promoted an increase in CFU-GM numbers from GM-CSF, but not PIXY321, pretreated stromal cocultures. The results demonstrate that post-chemotherapy marrow stromal layers were deficient in supporting in vitro hematopoiesis and suggest that negative regulators induced by chemotherapy and cytokines may be one cause for this defect.  相似文献   
102.
A fusion protein, FX–CBDCex, which comprises factor Xwith a cellulose-binding domain (CBDCex) fused to its C-terminus,was produced in BHK cells. It was purified from the culturemedium by affinity chromatography on cellulose. FX–CBDCexcould be activated to FXa–CBDCex with Russell viper venom.FXa–CBDCex was as active as FXa against a chromogenicsubstrate and against proteins containing the Ile–Glu–Gly–Argsequence hydrolysed by FXa. FXa–CBDCex retained its activitywhen adsorbed to cellulose.  相似文献   
103.
Depression is a significant problem in epilepsy. Suicides occur in epileptic patients five times more often than in general population. Material included 34 epileptics with 76 suicidal attempts and 24 patients with no history of suicide. Psychical state was studied with Beck Depression Inventory and Hamilton Depression Rating Scale. In the group with suicidal attempts 65% of patients had depression (54.5% of them had major depression) and in group without suicide attempts depression was noted in 54% (23% with major depression). Patients with depression were divided into two groups: group I with suicidal attempts and group II without history of suicide. In group I more patients were alcohol abusers (50% vs 31%), more were treated because of epilepsy longer than 10 years (59% vs 46%) and more had tonic-clonic seizures (82% vs 46%). In group I, 54% of patients were on polytherapy (more than half of them with fenobarbital). In group II, 31% of epileptics were on polytherapy (no one with fenobarbital). Major depression was significantly more frequent in epileptics with suicidal attempts. The severity of depression may influence the risk of suicide. Major depression may be associated with late age of onset of epilepsy, longer treatment duration, tonic-clonic seizures, polytherapy (mainly with fenobarbital) and alcohol abuse.  相似文献   
104.
The amino acids of prickly pear (Opuntia ficus indica L.) proteins, free amino acids and nonvolatile organic acids were determined on fresh and lyophilised young pads. The calculated biological value of prickly pear protein was 72.6, relative to egg protein. Trace amounts of malonic, malic and citric acids in material collected at 1800 hours; traces 0.95 and 0.31 mg g?1, respectively. In similar material analysed at 0600 hours, the concentrations of those acids were 0.36, 9.85, and 1.78 mg g?1, respectively. Since there was a significant accumulation of the acids during the evening, crassulacean-type metabolism is suggested.  相似文献   
105.
BACKGROUND: Topical antimicrobials have been considered for treatment of secondarily infected wounds because of the potential for reduced risk of adverse effects and greater patient convenience. We compared mupirocin cream with oral cephalexin in the treatment of wounds such as small lacerations, abrasions, or sutured wounds. METHODS: In 2 identical randomized double-blind studies, 706 patients with secondarily infected wounds (small lacerations, abrasions, or sutured wounds) received either mupirocin cream topically 3 times daily or cephalexin orally 4 times daily for 10 days. RESULTS: Clinical success at follow-up was equivalent in the two groups: 95.1% and 95.3% in the mupirocin cream and the cephalexin groups, respectively (95% confidence interval [CI], -4.0% to 3.6%; P = .89). The intention-to-treat success rate was 83% in both groups. Bacteriologic success at follow-up was also comparable: 96.9% in the mupirocin cream and 98.9% in the cephalexin groups (95% CI, -6.0% to 2.0%; P = .22). The occurrence of adverse experiences related to study treatment was similar for the 2 groups, with fewer patients in the mupirocin cream group reporting diarrhea (1.1% vs 2.3% for cephalexin). CONCLUSIONS: Mupirocin cream applied topically 3 times daily is as effective as oral cephalexin given 4 times daily for the treatment of secondarily infected wounds and was well tolerated.  相似文献   
106.
A patient with the acquired immunodeficiency syndrome developed bilateral retinitis due to a Bartonella (formerly Rochalimaea) henselae infection. A retinal biopsy was performed when severe and progressive retinal infection failed to respond to empirical treatment for cytomegalovirus and Toxoplasma gondii. The biopsy specimen was stained with routine histopathological stains and the Steiner silver stain. Ribosomal DNA was extracted from formalinfixed, paraffin-embedded retinal tissue and amplified with the polymerase chain reaction assay, using Bartonella-specific primers. The amplified DNA fragment was cloned and sequenced. Staining with hematoxylin-eosin revealed tufts of proliferating vascular endothelium with numerous fusiformappearing cells, consistent with a diagnosis of bacillary angiomatosis. A Steiner silver stain revealed numerous small bacilli in the biopsy specimen. Amplification of DNA extracted from the tissue produced a fragment of 16S ribosomal DNA of the expected size; sequencing of the DNA fragment revealed that the infection was caused by B henselae. The retinal infection was treated with minocycline, doxycycline, and ciprofloxacin with improvement in visual acuity in the ensuing 12 weeks. To our knowledge, this is the first human immunodeficiency virus-infected patient with retinitis due to B henselae who was diagnosed by the identification of silver-staining bacilli and amplification and sequencing of B henselae with a polymerase chain reaction assay using a biopsy specimen of retinal tissue. Retinal biopsy is indicated, despite its potential for serious complications, in patients with acquired immunodeficiency syndrome who have a progressive, sight-threatening retinitis that is undiagnosed and unresponsive to therapy.  相似文献   
107.
108.
Iso-thermalgravimetric analysis has been used by many authors in studying the degradation mechanism of PVC. For the PVC compounder though this same method provides a reliable means of determining the efficiency and cost effectiveness of commercial PVC stabilizers. Thermal stability of PVC resins stabilized with organotin, antimony, and ester stabilizers are presented and compared with data obtained by conventional Brabender Plasticorder and post extrusion oven aging tests. In addition a method is presented to establish the relative stability and cost effectiveness of a stabilizer at given concentrations currently familiar to the rigid PVC compounder.  相似文献   
109.
Studied the effects of the motives to approach success and to avoid failure in 60 5th and 6th grade boys and girls of low, middle, and high levels of test anxiety (Test Anxiety Scale for Children and Lie Scale for Children). Ss performed addition problems under 1 of 2 conditions: a mixed condition involving two-thirds success and one-third failure under time pressure and a success only condition in which all problems attempted were completed. As predicted, high anxious Ss, when compared to less anxious Ss on response rate, errors, and cheating, showed markedly inferior performance in the mixed condition, but comparable and improved performance in the success only condition. Findings indicate that anxious children perform poorly due to motivational difficulties rather than to learning deficiencies, and that their abilities are systematically underestimated by many achievement and educational testing procedures. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
110.
The performance of platinum/iridium coated titanium anodes under electrolytic conditions typical of those encountered in copper electrowinning applications has been studied. The corrosion loss of coating totalled approximately 1.5 μg/A · h during normal operation with a preferential loss of platinum from the coating. Anode potentials were observed to increase with time and the onset of complete electrode degradation was accompanied by a large increase of anode potential together with a loss of coating by spalling. The mechanism of coating loss and anode degradation is discussed. Graduate Student, University of British Columbia, Department of Metallurgy  相似文献   
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