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991.
K Tamazawa H Arima T Kojima Y Isomura M Okada S Fujita T Furuya T Takenaka O Inagaki M Terai 《Journal of medicinal chemistry》1986,29(12):2504-2511
Four enantiomers (3a-d) of the title compound, YM-09730 (3), were synthesized by the reaction of (-)- or (+)-5-(methoxycarbonyl)-2, 6-dimethyl-4-(m-nitrophenyl)-1,4-dihydropyridine-3-carboxylic acid (1a or 1b) with (S)- or (R)-1-benzyl-3-pyrrolidinol (2a or 2b). [3H]Nitrendipine binding affinity and coronary vasodilating activity of these compounds were evaluated. The absolute configuration of the most potent enantiomer (3a) with the longest duration was unequivocally determined to be (S)-1,4-dihydropyridine-C4 and (S)-pyrrolidine-C3 (S,S) by X-ray crystallographic study on 3a X HBr as well as 3a X HCl. The configuration of 1a corresponds to R, and the other enantiomers of 3 were respectively determined by chemical correlation. The potency order of the four enantiomers was (S,S)-3a greater than (S,R)-3b greater than (R,R)-3d greater than (R,S)-3c. Latent chiral characters of nifedipine derivatives with the identical ester groups were assigned by comparison of their puckering modes of 1,4-dihydropyridine (DHP) rings with those found in 3a X HCl or 3a X HBr. On the basis of the assignment, it has been revealed that the (S)-DHP nifedipine derivatives possess the synperiplanar carbonyl group at C5. The conformational restriction may be a factor causing stereoselectivity of antagonism. 相似文献
992.
The interaction of an organic acid with sodium bicarbonate in water produces an effervescent reaction. The reaction products are carbon dioxide, water, and the sodium salt of the acid. The kinetic rate-determining step for this reaction is the dehydration of carbonic acid. The solid-solid interaction with known amounts of moisture was followed by quantitatively determining carbon dioxide evolution as a function of time. The aqueous solubilities, diffusion coefficients, dissociation constants, and solid-solid interaction rates of six different substituted benzoic acids were determined. Using a model based on diffusion of the organic acid through the aqueous layer coupled with chemical reaction, predicted rates and levels of carbon dioxide production were compared with experimental results. Included in the model were the effects of the reaction products on the solution properties of the reactants. It was found that high concentrations of substituted sodium benzoate were generated very quickly and affected the solubility of the reactants, diffusion coefficient of the acid, and the carbonic acid dehydration rate constant. Moisture content was found to have a profound influence on the interaction rate. Water provides a medium for diffusion of the reacting species as well as the reaction solvent. 相似文献
993.
Mohammed E Abushaiqa Frank K Zaran David S Bach Richard T Smolarek Margo S Farber 《American journal of health-system pharmacy》2007,64(11):1170-1173
PURPOSE: Educational interventions to reduce the use of abbreviations and dosage designations that were deemed unsafe at a level 1 trauma center are described. SUMMARY: Strategies to reduce the use of unsafe abbreviations at Detroit Receiving Hospital were studied. Six abbreviations and dosage designations were deemed as unsafe by the site's medication-use and patient medical safety committees: (1) U for units, (2) microg for microgram, (3) TIW for three times a week, (4) the degree symbol for hour, (5) trailing zeros after a decimal point, and (6) the lack of leading zeros before a decimal point. Data on abbreviation use was collected starting in September 2003 by examining copies of patients' order sheets, which are sent from nursing units to the pharmacy for processing. Data were collected during three 24-hour periods each month, with 7-10 days between each period. A data collection sheet was developed to assist in documenting the number of opportunities for each unsafe abbreviation and the actual incidence of each. Educational strategies were developed and implemented starting in October 2003 to decrease the use of the unsafe abbreviations. These strategies included inservice education programs for the medical, pharmacy, and nursing staffs; laminated pocket cards; patient chart dividers; stickers; and interventions by pharmacists and nurses during medication prescribing. During the eight-month evaluation period, 20,160 orders were reviewed, representing 27,663 opportunities to use a designated unsafe abbreviation. Educational interventions successfully reduced the overall incidence of unsafe abbreviations from 19.69% to 3.31%. CONCLUSION: Educational interventions markedly reduced the use of unsafe abbreviations in medication orders over an eight-month evaluation period. 相似文献
994.
ImmunoCyt/uCyt is a fluorescent test combining three monoclonal antibodies. In this study, it has been tested as a complement to cytology in the detection of urothelial carcinoma in urine. It has been performed simultaneously with standard cytology and cystoscopy on 870 urine analyses from one hospital. In 136 cases, one or more bladder tumors were found. Overall sensitivity of cytology, ImmunoCyt/uCyt and combined analyses reached 29, 74 and 84%, respectively, and overall specificity was 98, 62 and 61%. The negative predictive value of cytology, ImmunoCyt/uCyt and both analyses was 88, 93 and 95%, respectively, and the positive predictive value was 70, 26 and 29%. The sensitivity of cytology for low malignant potential neoplasms, low- and high-grade papillary carcinomas was 6, 18 and 53%, while it reached 71, 79 and 93% when combined with ImmunoCyt/uCyt. The sensitivity of cytology for stages Ta, T1, T2 and over and Tis tumors was 12, 67, 47 and 50%, while it reached 78, 83, 79 and 100% when combined with ImmunoCyt/uCyt. In the absence of tumor on cystoscopy but with positive ImmunoCyt/uCyt, 18% of patients developed a tumor, 2-6 months later. Of the 109 cases diagnosed as suspicious for malignancy by cytology, a tumor was present in 30 cases and ImmunoCyt/uCyt was positive in 22 (73%) of them. In conclusion, ImmunoCyt/uCyt may be used to postpone cystoscopies in patients followed for bladder cancer and may help to save cytologist and pathologist screening time. 相似文献
995.
996.
Practical management of patients with non-small-cell lung cancer treated with gefitinib. 总被引:7,自引:0,他引:7
Neelam T Shah Mark G Kris William Pao Leslie B Tyson Barbara M Pizzo Murk-Hein Heinemann Leah Ben-Porat Dana L Sachs Robert T Heelan Vincent A Miller 《Journal of clinical oncology》2005,23(1):165-174
PURPOSE: The use of gefitinib, the first drug approved to inhibit the epidermal growth factor receptor tyrosine kinase, is indicated in patients with non-small-cell lung cancer with tumors progressive after chemotherapy. The unique mechanism of action of this agent leads to distinctive patterns of response and toxicity in persons with lung cancer. Many of the principles of management relevant to gefitinib are distinct from those with conventional cytotoxic drugs. To meet this need, we present practical guidelines on the use of gefitinib in patients with non-small-cell lung cancer. METHODS: This article reviews gefitinib's indications, dosing, response phenomena, and patterns of relapse in individuals with radiographic response. RESULTS: We present our recommendations for the management of rash and diarrhea caused by this agent. CONCLUSION: This information can guide practitioners and help them inform their patients about what to expect when they receive gefitinib. 相似文献
997.
IPEX (immunodysregulation, polyendocrinopathy, enteropathy, X linked syndrome) is a rare disorder which usually results in death in early infancy or childhood. Clinical awareness remains the cornerstone of diagnosis, and provided that the diagnosis is entertained, mutation analysis for FOXP3 gene mutations can be confirmatory. Two new patients in whom IPEX was diagnosed retrospectively are reported. 相似文献
998.
AIM: To report the treatment of a recurrent adenoid-cystic carcinoma of the lacrimal gland required orbital exenteration with an en bloc resection of the lateral orbital rim and wall and an anterior portion of the temporal muscle. Reconstruction was planned with both the objectives of a shortened healing time for faster epithetic reconstruction and no visible scars. METHOD: After a cranially extended temporal approach, the dissection of the superficial galea layer was connected with the subcutaneous dissection of the upper and lower eyelid after subciliary incisions. RESULTS: Ample exposure of the temporal, frontal and orbital region was obtained, facilitating the orbital exenteration with en bloc resection of the lateral orbital rim and wall and the anterior portion of the temporal muscle. The epithelialization of the eye socket covered with the galea fascia flap was accelerated, providing faster epithetic reconstruction, without visible scars. CONCLUSIONS: Healing time is accelerated, providing faster epithetic rehabilitation without visible scars, which is important in the postoperative rehabilitation ladder after eye exenteration for both patient and surgeon. Further more ablative surgery within this region gets safer and easier due to the ample exposure of this innovative surgical technique. Further evaluation of the effectiveness and safety of this new approach is advisable. 相似文献
999.
1000.