利用除尘灰制备高效脱硫剂

利用Ca(OH)₂和钢铁企业的除尘灰作为原料,通过不同的方法制备脱硫剂,在流化床反应器中进行脱硫性能实验,考察脱硫效率在95%以上的持续时间及钙利用率等指标,对其脱硫性能进行了比较.实验结果表明,除尘灰A中Fe₂O₃和FeO含量高,作为添加剂与Ca(OH)2混合焙烧后,钙利用率从18.2%提高到70.2%,脱硫效率在95%以上的持续时间从11min延长到31min.除尘灰A作为添加剂与Ca(OH)₂混合焙烧,制备半干法烟气脱硫的高效脱硫剂,可以较大地提高钙利用率,对于烧结烟气脱硫具有重要的实用价值.     

Eleven components of effective drug abuse prevention curricula

A review of school-based drug abuse prevention programs was conducted for 1989-1994. In addition to a comprehensive literature review, interviews were conducted with a panel of 15 leading experts in prevention research. Key elements of promising prevention curricula were identified. Effective prevention programs were found to be based on a sound theoretical or research foundation. They included developmentally appropriate information about drugs, social resistance skills training, and normative education. Broader based personal and social skills training appeared to enhance program effects. Effective programs used interactive teaching techniques and teacher training, and provided adequate coverage and sufficient follow-up. Cultural sensitivity to the target population was found to be critical to program success. Additional program components were expected to enhance curriculum effectiveness. Finally, experts agreed that adequate evaluation of prevention curricula was critical. Unfortunately, despite information about the types of curricula that are effective, the most promising prevention curricula are not widely disseminated. Reasons for under-utilization are explored, and recommendations made for correcting the situation.     

The stepladder technique: An alternative group structure facilitating effective group decision making.

A new group problem-solving structure entitled the stepladder technique is introduced. The stepladder technique is intended to allay the problems associated with group decision making by structuring the entry of group members into a core group and by ensuring that each member contributes to the decision-making process. Four-person groups, randomly assigned to either the stepladder group condition (15 groups) or the conventional group condition (15 groups), performed D. Johnson and F. Johnson's (1987) winter survival exercise. Stepladder groups produced significantly (p?     

Organic nitrates--new perspectives on an old drug group

A quarter of patients with erythropoietic protoporphyria develop mild to severe cholestatic liver disease. The determination of early indicators of hepatobiliary involvement are of pivotal importance to select patients for choleretic therapy. Porphyrin parameters were studied during ursodeoxycholic acid treatment in eight patients with protoporphyrin-associated liver disease and eight patients with liver failure before and after liver transplantation. The patients with intrahepatic cholestasis exhibited excessive protoporphyrinemia (27 mumol/l) compared with controls (normal < 0.64 mumol/l). Fecal protoporphyrin excretion decreased in patients with deterioration of liver function, whereas urinary coproporphyrin increased up to 2290 nmol/24 h (normal < 119 nmol/24 h). Coproporphyrin isomer I proportion increased to 71 +/- 10% (mean +/- SD, n = 8) in patients with terminal liver failure (normal < 31%). During therapy with ursodeoxycholic acid biochemical improvement occurred but without clinical remission in most cases. Eight patients underwent liver transplantation between 1987 and 1997. One patient died of liver failure. Two transplant recipients are in a good condition since 8 and 9 years, respectively. All explanted livers revealed micronodular cirrhosis and high protoporphyrin levels of about 25,000-fold (mean, n = 3). Immediately after liver transplantation protoporphyrin in erythrocytes decreased to 46-96% of pre-operative values. Coproporphyrin remained moderately elevated due to post-operative cholestasis. A post-operative rise in fecal protoporphyrin elimination reflected sufficient biliary clearence of protoporphyrin by the transplant. In conclusion, moderate coproporphyrinuria with isomer I is the earliest sign of liver complications in erythropoietic protoporphyria. Progression of protoporphyrin induced toxic liver injury is indicated by excessive protoporphyrinemia and coproporphyrinuria with an isomer I proportion > 71 +/- 10%, and reduction of fecal protoporphyrin excretion. Results suggest that therapy of intrahepatic cholestasis with ursodeoxycholic acid is only effective in the initial stages of liver disease in erythropoietic protoporphyria. In patients with severe cholestatic hepatic failure, liver transplantation is the treatment of choice.     

Two similar peptides from the venom of the scorpion Pandinus imperator, one highly effective blocker and the other inactive on K+ channels

Two novel peptides, named Pi4 and Pi7, were purified from the venom of the scorpion Pandinus imperator, and their primary structures were determined. These peptides have 38 amino acids residues, compacted by four disulfide bridges, instead of the normal three found in most K+-channel specific toxins. Both peptides contain 25 identical amino acid residues in equivalent positions (about 66% identity), including all eight half-cystines. Despite the fact that their C-terminal sequence comprising amino acid residues 27 to 37 are highly conserved (10 out of 11 amino acids are identical), Pi4 blocks completely and reversibly Shaker B K+ -channels (a Kv1.1 sub-family type of channel) at 100nM concentration, whereas Pi7 is absolutely inactive at this concentration. Similar effects were observed in binding and displacement experiments to rat brain synaptosomal membranes using 125I-Noxiustoxin, a well known K+-channel specific toxin. In this preparation Pi4 displaces the binding of radiolabeled Noxiustoxin with Ic50 in the order of 10 nM, whereas Pi7 is ineffective at same concentration. Comparative analysis of Pi4 and Pi7 sequences with those obtained by site directed mutagenesis of Charybdotoxin, another very well studied K -channel blocking toxin, shows that the substitution of lysine (in Pi4) for arginine (in Pi7) at position 26, might be one of the important 'point mutations' responsible for such impressive variation in blocking properties of both toxins, here described.     

Highly effective separation and highly sensitive detection for clinical chemistry and biochemistry

Highly effective separation and highly sensitive detection reagents for clinical chemistry and biochemistry were developed and their applications were investigated. The sensitive detection of carboxylic acids was accomplished using 9-anthryldiazomethane (ADAM) which gave intensely fluorescent derivatives from carboxylic acids without catalysts or heating. 1-Pyrenyldiazomethane was then synthesized and proved to react also readily with carboxylic acid and more sensitive than ADAM. The optical resolution of amino acid enantiomers was achieved using 2,3,4,6-tetra-O-acetyl-beta-D-glucopyranosyl isothiocyanate (GITC). GITC derivatized enantiomeric amino acids under mild conditions to give highly hydrophobic diastereomers which could be resolved on conventional reversed phase columns and easily detected by the absorption based on the thiourea structure. Then we devised an o-phthalaldehyde-N-acetylcystein reagent (OPA/NAcCys) giving diastereomers which were also resolved on a reversed phase column and detected fluorometrically with excellent sensitivity. OPA/NAcCys was useful for the assay of D-amino acids in the blood of uremic patients. The hypochlorite-thiamine method for the assay of proteins and peptides was established providing sensitive fluorometry, which well reflected the number of peptide groups in the molecule. This principle was applied to the assay using N-chlorodansylamide, designed for the fluorometry of peptides. The alkaline ninhydrin method was applied to the detection of guanidino compounds in the blood of uremic patients. Several fluorometric methods for the simultaneous detection of reducing and non-reducing carbohydrates, and guanidines were found to be useful reagents for this purpose because these compounds were resistant to the oxidation with periodate. Then protamine-bound columns were prepared for the separation of carbohydrates on HPLC, which showed excellent recovery of reducing carbohydrates in comparison with conventional alkylamino columns.     

Risedronate, a highly effective oral agent in the treatment of patients with severe Paget's disease

Thirteen patients with severe Paget's disease of bone [mean serum alkaline phosphatase (SAP) level 17 times the upper limit of normal] were treated with 30 mg oral risedronate daily for 8 weeks. Patients were followed for 16 weeks without treatment. The change from baseline SAP was the primary end point. Those patients whose SAP levels did not reach the normal range were retreated with 30 mg for another 8 weeks. There was a mean percent decrease in SAP of 77% after the first course of risedronate treatment and 87% after the second course of treatment. All patients who completed the study had a decrease in SAP of at least 77% from the baseline. The urinary hydroxyproline/creatinine level was decreased by 64% and 79%, respectively, during the first and second treatment courses. There were transient asymptomatic decreases in serum calcium and phosphorus levels. The urinary calcium/creatinine ratio also decreased in these patients. Serum intact PTH and 1,25-dihydroxyvitamin D levels increased transiently during risedronate treatment. Oral risedronate was well tolerated by the patients. Only one patient discontinued treatment because of an adverse event (diarrhea) thought to be related to risedronate therapy.     

简便高效测定熔盐电导率的新方法

提出一种简便高效的测定熔盐电导率的新方法———管式电导池法。该方法采用热解氮化硼管自制电导池，以钨丝作为工作电极，石墨作为对电极，采用阻抗仪测定nNaF·AlF3-Al2O3-CaF2熔盐的电阻，并与Wang 经验公式和Choudhary 经验公式计算所得电导率数据进行比较。结果表明，自制的管式电导池法所测得数据与经验公式计算得数据相近，并且有较好的准确性和重现性。管式电导池法是一种准确度高、结构简单、造价便宜、能扩大应用范围测定熔盐电导率的有效测试手段。     

Bioequivalence of a highly variable drug: an experience with nadolol

PURPOSE: To assess the bioequivalence of nadolol 40mg and 160mg tablets (Zenith-Goldline Pharmaceuticals) using Corgard 40mg and 160mg tablets (Bristol-Meyers Squibb) as reference products, to estimate the effect of food in the gastrointestinal tract on nadolol bioavailability, and to evaluate the effectiveness of standard pharmacokinetic metrics AUCt, AUC infinity, and Cmax in bioequivalence determinations. METHODS: Four bioequivalence studies were conducted as described in the FDA Guidance. Four additional studies of varying designs were conducted to establish bioequivalence of the 40mg tablet in terms of Cmax. RESULTS: Fasted and food-effect studies of the 160mg tablet clearly established bioequivalence and revealed an unexpected reduction in nadolol bioavailability from test and reference products in the presence of food. The food-effect study of the 40mg tablet (80mg dose) revealed a similar reduction in bioavailability from each product. Fasted studies of the 40mg tablet (80mg dose) established bioequivalence in terms of AUCt and AUC infinity. However, Cmax criteria proved extremely difficult to meet in the initial 40mg fasted study because of the large variability, leading to additional studies and ultimately requiring an unreasonable number of subjects. CONCLUSIONS: Final results clearly established bioequivalence of both strengths and characterized an unexpected food effect which did not appear to be formulation-related. However, the Cmax of nadolol is only slightly sensitive to absorption rate and the relatively large variability of Cmax reduces its effectiveness as a bioequivalence metric. Findings suggest that bioequivalence criteria for highly variable drugs should be reconsidered.     

In vitro activity of the new fluoroquinolone CP-99,219

The in vitro activity of the new fluoroquinolone CP-99,219 [7-(3-azabicyclo[3.1.0]hexyl)naphthyridone] was compared with those of four other quinolones against 541 gram-negative, 283 gram-positive, and 70 anaerobic bacterial isolates. CP-99,219 inhibited 90% of many isolates in the family Enterobacteriaceae at a concentration of < or = 0.25 micrograms/ml (range, < 0.008 to 1 microgram/ml), an activity comparable to those of tosufloxacin and sparfloxacin and two times greater than that of temafloxacin. Ninety percent of the Proteus vulgaris, Providencia rettgeri, Providencia stuartii, and Serratia marcescens isolates were inhibited by 0.5 to 2 micrograms of CP-99,219 per ml. CP-99,219 inhibited 90% of the Pseudomonas aeruginosa and Haemophilus influenzae isolates at 1 and 0.015 micrograms/ml, respectively. The compound inhibited methicillin-susceptible Staphylococcus aureus at 0.06 micrograms/ml, whereas a ciprofloxacin concentration of 1 microgram/ml was required to inhibit these organisms. CP-99,219 inhibited 90% of methicillin-resistant S. aureus isolates at a concentration of < or = 4 micrograms/ml, while ciprofloxacin and temafloxacin had MICs against these isolates of > 16 micrograms/ml. Streptococci were inhibited by < or = 0.25 micrograms/ml, an activity comparable to that of tosufloxacin. CP-99,219 was eight times more active than ciprofloxacin against Streptococcus pneumoniae. Bacteroides species were inhibited by CP-99,219 at a concentration of 2 micrograms/ml, whereas inhibition of these species required 4- and 16-microgram/ml concentrations of tosufloxacin and ciprofloxacin, respectively. The MBCs of CP-99,219 ranged from two to four times the MICs, and inoculum size had a minimal effect on MIC. CP-99,219 was active against P. aeruginosa at pH 5.5, with only a fourfold increase in MIC compared with values obtained at pH 7.5. The addition of up to 9 mM Mg(2+) increased the MIC range from 0.03 to 0.06 microgram/ml to 0.12 to 0.5 microgram/ml. In view of its excellent in vitro activity against both gram-positive and gram-negative bacteria, CP-99,219 merits further study to determine it's clinical pharmacologic properties and potential for therapeutic use.     

Reinforcing operants other than abstinence in drug abuse treatment: An effective alternative for reducing drug use.

This study examines the effectiveness of using vouchers to reinforce either the provision of urine samples testing negative for illicit drugs (UA group) or the completion of objective, individually defined, treatment-plan-related tasks (TP group). A third group was assigned to the clinic's standard treatment (STD group). Participants were randomly assigned to groups after a 6-week baseline stabilization period. Urine specimens were collected thrice weekly throughout the study. In the UA condition, participants earned $5 (U.S. dollars) in vouchers for each drug-free urine submitted. In the TP condition, participants earned up to $15 in vouchers per week for demonstrating completion of treatment plan tasks assigned by their counselors. Contingencies were in effect for 12 weeks, after which all participants received the clinic's standard treatment. Urinalysis results indicate that the TP intervention was significantly more effective in reducing illicit drug use than either the UA or STD interventions. These effects were maintained with a trend toward continuing improvement for the TP groups even after contingencies were discontinued. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Predicting effective drug concentrations for individual patients. Determinants of pharmacodynamic variability

To study the diversity of protocadherins, a rat brain cDNA library was screened using a cDNA for the cytoplasmic domain of human protocadherin Pcdh2 as a probe. The resultant clones contained three different types. One type corresponds to rat Pcdh2; the other two types are distinct from Pcdh2 but contain the same sequence in their cytoplasmic domains and part of the 3' flanking sequence. To clarify the structure of the proteins defined by the new clones, a putative entire coding sequence corresponding to one of the clones was determined. The overall structure is essentially the same as Pcdh2, indicating that the proteins defined by this clone, and probably by other clones, belong to the protocadherin family. Two PCR experiments and an RNase protection assay showed the existence of the corresponding mRNAs in rat brain preparations. Human and mouse cDNA clones with the same sequence properties were also isolated. Taken together, these results indicate that the clones are not cloning artifacts and that corresponding mRNAs are actually expressed in brains of various species. The results of in situ hybridization showed that the mRNAs corresponding to these clones were expressed in different regions in brain. Since protocadherins encoded by these mRNAs are likely to have different specificity in their interaction and share a common activity at their cytoplasmic domains, these protocadherins may provide a molecular basis, in part, to support the complex cell cell interaction in brain.     

Growth of highly perfect metal crystals from the melt

Abstract

The nature, origin and control of chemical and structural imperfections in melt-grown single crystals is discussed. Chemical imperfections considered include long-range solute segregation, banding, cellular segregation and dendritic segregation. Structural imperfections discussed include grain boundaries, lineage (striation) substructure and dislocations. Precautions necessary to minimize the number of such imperfections are outlined.

Résumé

La nature, l'origine et Ie contrôle des imperfections structurales ou de composition dans des monocristaux tirés d'un liquide sont discutés. Les imperfections de composition considérées sont la ségrégation à longue distance du soluté, la structure en bande, la ségrégation cellulaire et dendritique. Les imperfections structurales étudiées son ties joints de grains, les sous-structures et les dislocations. Les précautions à prendre pour éviter ces défauts sont données.     

Augmenting continuing education with psychologically focused group consultation: Effects on adoption of group drug counseling.

This study examines whether adding psychologically focused group consultation to a standard 1-day continuing-education workshop on Group Drug Counseling (GDC), a group therapy with evidence of effectiveness in the treatment of substance abuse problems, improves GDC adoption. Counselors who had taken a 1-day workshop were randomly assigned to an 8-week course of group consultation that met for 1.5 hr per session (n = 16) or to no additional contact (n = 14). The group consultation used Relapse Prevention and Acceptance and Commitment Therapy principles to help participants overcome psychological barriers to the adoption of GDC. Results showed that the 1-day workshop resulted in attempts by trainees to implement the new therapy, but that the consultation condition maintained significantly higher levels of adoption and 2- and 4-month followups. Additionally, those in the group consultation condition reported a higher sense of personal accomplishment at the 4-month followup. These findings suggest that empirically supported psychotherapy models can be used to decrease clinicians' psychological barriers to adoption of evidence-based psychotherapy methods. (PsycINFO Database Record (c) 2010 APA, all rights reserved)