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991.
Dimick JB Cowan JA Stanley JC Henke PK Pronovost PJ Upchurch GR 《Journal of vascular surgery》2003,38(4):739-744
OBJECTIVE: This study was undertaken to determine the relative importance of surgeon specialty, hospital volume, and surgeon volume on outcome after abdominal aortic aneurysm (AAA) repair. METHODS: Data were reviewed for 3912 patients undergoing AAA repair in the Nationwide Inpatient Sample during 1997. In-hospital mortality was compared between high-volume hospitals and low-volume hospitals and between high-volume surgeons and low-volume surgeons. High-volume hospitals performed more than 35 AAA repairs per year, and high-volume surgeons performed more than 10 AAA repairs per year. Vascular, cardiac, and general surgery specialization was identified by analysis of other procedures performed by each surgeon. RESULTS: Overall, AAA repair mortality was 4.2%, and was lower at high-volume hospitals (3.0%) than at low-volume hospitals (5.5%) (P <.001). Lowest mortality was associated with operations performed by vascular surgeons (2.2%) compared with cardiac surgeons (4.0%) and general surgeons (5.5%) (P <.001). Mortality rates were also lower for high-volume hospitals (2.5%) compared with low-volume hospitals (5.6%) (P <.001). In a risk-adjusted analysis, high-volume hospital, vascular surgery specialty, and high-volume surgeon were all independently associated with lower risk of in-hospital mortality. In this analysis, risk reduction was 30% for high-volume hospitals (95% confidence interval [CI], 2%-51%; P <.05) and 40% for surgery by a high-volume surgeon (95% CI, 12%-60%; P =.01). AAA repair by general surgeons compared with vascular surgeons was associated with 76% greater risk for death (95% CI, 10%-190%; P =.02). No significant difference in mortality was found between cardiac and vascular surgeons. CONCLUSIONS: High surgeon volume and hospital volume of AAA repair were both associated with lower mortality compared with low-volume providers. Increased specialization in vascular surgery was associated with markedly decreased mortality independent of AAA repair volume. Health policy in support of selective referral for AAA repair should consider surgical specialization in addition to provider volume thresholds. 相似文献
992.
993.
Purpose. This study was designed to illustrate the feasibility of using soluble CD47 protein to antagonize phagocytosis of colloidal drug carriers by macrophages.
Methods. Expression of CD47-streptavidin (CD47-SA) fusion protein was achieved in B21CodonPlus host cells following IPTG induction. Murine macrophage cell line J774A.1, expressing high levels of SIRP, was selected as the biologic model system for phagocytosis. FITC-labeled perfluorocarbon (PFC) emulsions were used as the colloidal carriers to trigger phagocytosis. Microscopy (inverted light and UV-fluorescence) and flow cytometry were used to qualitatively and quantitatively determine the degree of phagocytosis, respectively.
Results. The bacterially expressed, purified CD47-SA had neither cytotoxic nor cytostatic effects when incubated with J774A.1 cells up to a concentration of 400 nM for 24 h. Phagocytosis of FITC-labeled PFC emulsions was significantly diminished when macrophages were pretreated with 100 nM CD47-SA for 1 h.
Conclusions. We demonstrated that soluble CD47-SA antagonized phagocytosis of colloidal carriers to a significant degree by interaction with macrophage SIRP. 相似文献
994.
Bindal A Narsimhan G Hem SL Kulshreshtha A 《Pharmaceutical development and technology》2003,8(3):219-228
The effect of steam sterilization (dwell@121 degrees C) on the apparent viscosity of solutions of carbomer 940P, guar gum, hydroxyethylcellulose (HEC), and xanthan gum was studied. Guar gum and carbomer 940P could be steam sterilized for 30 min without any change in the apparent viscosity. Steam sterilization of HEC and xanthan gum resulted in a substantial decrease in the apparent viscosity and the desirable shear-thinning rheology. The addition of sodium chloride to either polymer prior to steam sterilization diminished the effect of sterilization on the rheology. The apparent viscosity of xanthan solutions was not significantly affected if the solution was made isotonic with sodium chloride (0.15 M). The addition of sodium chloride to xanthan gum after steam sterilization resulted in full recovery of the initial rheological properties. Carbomers, guar gum, and xanthan (in 0.15 M NaCI) are candidates for use in pharmaceutical solutions/suspensions that are subjected to steam sterilization. 相似文献
995.
CONTEXT: A woman's ability to obtain an abortion is affected both by the availability of a provider and by accessrelated factors such as cost, convenience, gestational limits and the provision of early medical abortion services.
METHODS: In 2001-2002, The Alan Guttmacher Institute surveyed all known abortion providers in the United States, collecting information on their delivery of abortion services and on the number of abortions performed.
RESULTS: A minority of abortion providers offer services before five weeks from the last menstrual period (37%) or after 20 weeks (24% or fewer), but the proportions have increased since 1993. Providers estimate that one-quarter of women having abortions in nonhospital facilities travel 50 miles or more for services, and that 7% are initially unsure of their abortion decision. The majority of providers (59%) say that these clients usually receive abortions during a single visit. An average self-paying client was charged $372 for a surgical abortion at 10 weeks in 2001, up from $319 in 1997; only 26% of clients receive services billed directly to public or private insurance. Early medical abortions are becoming increasingly available but are more expensive than surgical abortions. More than half (56%) of providers experienced antiabortion harassment in 2000, but types of harassment other than picketing have declined since 1996.
CONCLUSIONS: Abortion at very early and late gestations and early medical abortion are more available than before, but charges have increased and antiabortion picketing remains at high levels. Thus, many women still face substantial barriers to obtaining an abortion. 相似文献
METHODS: In 2001-2002, The Alan Guttmacher Institute surveyed all known abortion providers in the United States, collecting information on their delivery of abortion services and on the number of abortions performed.
RESULTS: A minority of abortion providers offer services before five weeks from the last menstrual period (37%) or after 20 weeks (24% or fewer), but the proportions have increased since 1993. Providers estimate that one-quarter of women having abortions in nonhospital facilities travel 50 miles or more for services, and that 7% are initially unsure of their abortion decision. The majority of providers (59%) say that these clients usually receive abortions during a single visit. An average self-paying client was charged $372 for a surgical abortion at 10 weeks in 2001, up from $319 in 1997; only 26% of clients receive services billed directly to public or private insurance. Early medical abortions are becoming increasingly available but are more expensive than surgical abortions. More than half (56%) of providers experienced antiabortion harassment in 2000, but types of harassment other than picketing have declined since 1996.
CONCLUSIONS: Abortion at very early and late gestations and early medical abortion are more available than before, but charges have increased and antiabortion picketing remains at high levels. Thus, many women still face substantial barriers to obtaining an abortion. 相似文献
996.
997.
Central corneal thickness in Latinos 总被引:4,自引:0,他引:4
Hahn S Azen S Ying-Lai M Varma R;Los Angeles Latino Eye Study Group 《Investigative ophthalmology & visual science》2003,44(4):1508-1512
PURPOSE: To characterize central corneal thickness (CCT) in Latinos aged 40 or more years. METHODS: A population-based cohort of Latinos from two census tracts in La Puente, California, underwent measurements of CCT and intraocular pressure (IOP). CCT was measured with an ultrasonic pachymeter, and IOP was measured by applanation tonometry. One eye of each of 1699 participants was included in the analyses. RESULTS: The mean (+/-SD) CCT was 546.9 +/- 33.5 micro m. Older participants (>or=70 years) had significantly thinner CCs compared with participants 40 to 49 years of age (P < 0.05). Eyes with ocular hypertension had thicker CCs than did normal and glaucomatous eyes (P < 0.05). Multivariate adaptive regression spline analyses and analysis of variance contrasting IOP subgroups revealed that eyes with thinner CCs had lower IOP than did eyes with thicker CCs (P < 0.001). The absolute range of interocular differences in CCT in the same subject was as high as 24 micro m. CONCLUSIONS: On average, CCT in Latinos was less than that previously reported in whites but greater than that reported in African Americans and Asians. Older Latinos had thinner corneas compared with younger Latinos. Asymmetry in CCT of 25 micro m or more should be evaluated for potential corneal disease. Spline analyses suggest that although the relationship between IOP and CCT is best explained by a nonlinear equation, when measuring IOP with the Goldmann tonometer, it is likely that IOP is underestimated in eyes with thinner CCs and overestimated in eyes with thicker CCs. 相似文献
998.
The conduct of in vitro and in vivo drug-drug interaction studies: a PhRMA perspective 总被引:2,自引:0,他引:2
Bjornsson TD Callaghan JT Einolf HJ Fischer V Gan L Grimm S Kao J King SP Miwa G Ni L Kumar G McLeod J Obach SR Roberts S Roe A Shah A Snikeris F Sullivan JT Tweedie D Vega JM Walsh J Wrighton SA;Pharmaceutical Research Manufacturers of America Drug Metabolism/Clinical Pharmacology Technical Working Groups 《Journal of clinical pharmacology》2003,43(5):443-469
Current regulatory guidances do not address specific study designs for in vitro and in vivo drug-drug interaction studies. There is a common desire by regulatory authorities and by industry sponsors to harmonize approaches to allow for a better assessment of the significance of findings across different studies and drugs. There is also a growing consensus for the standardization of cytochrome P450 (CYP) probe substrates, inhibitors, and inducers and for the development of classification systems to improve the communication of risk to health care providers and patients. While existing guidances cover mainly CYP-mediated drug interactions, the importance of other mechanisms, such as transporters, has been recognized more recently and should also be addressed. This paper was prepared by the Pharmaceutical Research and Manufacturers of America (PhRMA) Drug Metabolism and Clinical Pharmacology Technical Working Groups and represents the current industry position. The intent is to define a minimal best practice for in vitro and in vivo pharmacokinetic drug-drug interaction studies targeted to development (not discovery support) and to define a data package that can be expected by regulatory agencies in compound registration dossiers. 相似文献
999.
Between October 4, 2001 and November 20, 2001, 22 cases of anthrax were identified in a bioterrorism attack on the US. This study examined the patterns of anthrax calls before and after the bioterrorist attack based on calls received by poison centers in Texas, a state that reported no anthrax cases as a result of the attack. During 1998-2002, 553 calls about anthrax were received. The majority of the anthrax calls occurred in 2001 (n = 489, 88.4%) and 2002 (n = 52, 9.4%). The number of calls increased greatly in the days after October 4, 2001, reaching a peak of 31 anthrax calls in 1 d and then declining sharply in succeeding months. However, by December 2002 the number of calls about anthrax still had not returned to pre-attack levels. This study demonstrated the value of poison centers in documenting public need for information on biological agents used in a terrorist attack, even if the attack did not occur in the area serviced by the poison center. Poison centers may expect to receive calls regarding a bioterrorist attack shortly after the public became aware of the attack and will continue to receive related calls for months afterward. Poison centers need to be prepared with appropriate information prior to such attacks to provide to the public upon request. 相似文献
1000.
A rapid, sensitive, and rugged method for detecting drugs and drug metabolites in extracts of horse urine is described. The use of large-volume injection (LVI) gas chromatography-mass spectrometry (GC-MS) for analysis of horse urine extracts allowed automation of the derivatization procedure and reduction of the sample volume from 5 mL to 1 mL of urine. An autosampler and temperature-programmable inlet were used to automatically dissolve the sample extract and form trimethylsilyl derivatives of over 200 analytes. The suitability of this procedure for routine GC-MS detection of approximately 80 basic analytes in extracts of racehorse urine was investigated. The formation of derivatives using LVI with in-liner derivatization was compared to a manual procedure involving the dissolution of sample extracts in N,O-bis(trimethylsily)trifluoroacetamide, heating the resulting mixture, and injecting 1 or 2 microL of the mixture through a splitless injector into the GC-MS instrument. In all cases, the in-liner derivatization reactions were found to be as complete as conventional heating block procedures. Ruggedness testing of the method demonstrated that peak resolution, shape, and area were maintained through 40 consecutive injections of sample extracts. No evidence of the accumulation of interfering substances was observed. The limits of detection using LVI GC-MS for routine screening of basic drugs in urine were generally in the range of 5-25 ng/mL. The method is currently being used to detect basic analytes in horse urine extracts with a throughput of approximately 50 urine sample extracts per instrument per day. 相似文献