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991.
OBJECTIVE: To report a simple, relatively rapid protocol to isolate biologically active bikunin from human urine using ion-exchange-trypsin affinity chromatography. Bikunin is a protease inhibitor which has been shown to play a role in various processes, including inhibition of calcium oxalate crystallization, the regulation of proliferation and modulation of carcinogenesis. The unavailability of the purified protein has hampered studies on bikunin's expanding role in these processes. MATERIALS AND METHODS: Female human urine was dialysed (15 kDa threshold) and crudely fractionated with a double-saturated ammonium sulphate precipitation. The first precipitation was with 35% saturated ammonium sulphate, and the supernatant was harvested, and the second with 90% saturated ammonium sulphate, and the precipitate collected. The protein mixture was then passed over Sepharose SP-fast-flow cation exchange and Sepharose Q-fast-flow anion exchange columns connected in series. The final purification was with a trypsin-affinity column which selectively bound bikunin. RESULTS: This procedure could recover 1 microg of bikunin per 2 mL of urine, and the final product was essentially free of contaminating inter-alpha-trypsin inhibitor heavy chains or bikunin-heavy chain conjugates. Product purity was confirmed by two-dimensional polyacrylamide gel electrophoresis combined with silver staining or Western blot. All isolations contained the 17 kDa minimally glycoslyated/sulphated form of bikunin and the 28 kDa form of bikunin. Some preparations also contained 33-48 kDa forms of bikunin. The protein cores of all three proteins were confirmed to be bikunin by mass spectrometry and Western blot. Harvested bikunin retained its trypsin inhibitory activity (L-benzoylarginine-p-nitroanilide assay). Preparations containing the 33-45 kDa form had two to three times more trypsin inhibitory activity than preparations without this band. CONCLUSIONS: This novel ion exchange-trypsin affinity chromatography protocol uses only two chromatographic steps. The product consists of three isomers of biologically active bikunin, free of contaminating heavy chains or bikunin-heavy chain conjugates. The ready availability of purified bikunin should facilitate future studies of bikunin's emerging role in urolithiasis, proliferation and carcinogenesis.  相似文献   
992.
Public health literacy in America: an ethical imperative   总被引:1,自引:0,他引:1  
One of public health professionals' major challenges is to provide the public with messages that are understandable and based on science. Traditionally, public health communication efforts have focused on the science behind the message rather than on how the information should be communicated and whether the message is understood. With more than one third of the U.S. population struggling with low health literacy, ensuring that individuals understand critical health messages is an ethical imperative for public health agencies, organizations, and professionals. This paper explores the ethical implications of public health literacy and the steps the public health community needs to take to promote a society that is public health literate.  相似文献   
993.
The purpose of this study is to compare three commonly used health-related quality of life (HR-QOL) questionnaires for their ease of use, accuracy, and patient preference; identify factors related to patient preference; identify differences in patient completion rates; and to identify factors associated with patient completion of these questionnaires. Three psychometrically sound measures, the Symptom Distress Scale (SDS), Medical Outcome Study Short Form-36 (SF-36), and Functional Assessment of Cancer Therapy (FACT), were tested. Seventy-nine patients completed questionnaires in the ambulatory oncology setting. No significant differences in patient ratings were found in ease of use and accuracy among the questionnaires. All of the questionnaires were rated as easy to use and accurate. Patient ratings on preference were marginally significant (p=0.07). Forty-six percent of participants indicated that they preferred the SDS, whereas 27 and 39 preferred the SF-36 and the FACT. No significant differences in patient completion rates were found among the questionnaires. One hundred percent completion rates ranged from 88.6 for the SDS to 78.5 for the SF-36, and 80 completion rates ranged from 98.7 for the SDS to 94.9 for the SF-36. Administration of standardized HR-QOL questionnaires is feasible in the clinical setting.This research was supported by an American Cancer Society Institutional Research Grant (IRG 58-012-42) through Yale Comprehensive Cancer Center and a grant from Bayer Pharmaceutical Company.  相似文献   
994.
995.
OBJECTIVE: To examine health and psychosocial correlates of persistent thinness in black and white young adult women. RESEARCH METHODS AND PROCEDURES: 1,830 females (n = 988 black, n = 842 white) who participated in the National Heart, Lung, and Blood Institute Growth and Health Study were asked to indicate their current body size from a series of nine pictograms (1, emaciated to 9, obese). Persistent thinness was defined as having at least seven non-missing measurement points between ages 9 to 18 with a body size rating of <4 at all points. Generalized linear models were used to examine whether persistently thin women differed from comparison women on cardiovascular disease risk factors measured at age 18.5 and psychosocial variables measured at age 21.5. Prospective associations between psychological measures in childhood and persistent thinness through the course of adolescence were also examined. RESULTS: In the sample, 145 women (7.9%) met criteria for persistent thinness and 1,685 women (92.1%) were classified as not persistently thin. Persistently thin women had a later age of menarche, fewer weight concerns, and healthier eating attitudes, were less likely to have had a child, came from higher socioeconomic backgrounds, and had significantly lower blood pressure and higher high-density lipoprotein-cholesterol than comparison women. Differences were not found on measures of depression or health services use. Girls with higher self-esteem in childhood were more likely to remain persistently thin throughout adolescence. DISCUSSION: Persistently thin women seem to be healthier on several indicators relative to comparison women, and race did not moderate these differences.  相似文献   
996.
We compared characteristics of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) skin and soft tissue infections (SSTIs) and CA-MRSA invasive disease identified in Minnesota from 2000 through 2003. A total of 586 patients with SSTIs and 65 patients with invasive disease were identified. Patients with invasive disease were more likely to be smokers (p = 0.03), and report a history of immunosuppressive therapy (p = 0.03), emphysema (p = 0.011), or injection drug use (p = 0.020) than were SSTI patients. Invasive disease isolates were less likely to be susceptible to ciprofloxacin (p = 0.002) and clindamycin (p = 0.001) and more likely to have healthcare-associated pulsed-field gel electrophoresis subtypes than SSTI isolates (p<0.001). Patients with invasive disease may have had healthcare exposures that put them at risk of acquiring healthcare-associated MRSA and which were not exclusion criteria in the CA-MRSA case definition. Continued surveillance of MRSA is needed to better characterize CA-MRSA infections.  相似文献   
997.
Objectives: Health-related services and compensatory mechanisms have a potential role in minimizing functional limitations and increasing quality of life among children with special health care needs (CSHCN). We examined whether rates of functional limitations among CSHCN in the 50 states and District of Columbia were associated with state-level characteristics that reflect access to such services among CSHCN. Methods: We aggregated child-level survey data from the National Survey of CSHCN to create 51 state-level estimates of the proportions who had functional limitations, had ≥1 unmet health needs, and lacked medical insurance coverage. State-level information about Medicaid spending per child enrollee in federal fiscal year 2000 was obtained from The Henry J. Kaiser Family Foundation website. We examined correlations between the percentages of CSHCN having functional limitations and each of the other state-level variables, and conducted multiple regression analyses that examined these associations while controlling for the statewide percentages of children living in poverty. Results: The proportions of CSHCN with functional limitations were higher in states with higher rates of uninsured CSHCN (r = .49; p < .0001) and higher rates of CSHCN with unmet health needs (r = .62; p < .0001). Proportions of CSHCN with functional limitations were unrelated to per child Medicaid spending. These findings were robust when we controlled for percentages of children in poverty across states. Conclusions: Fewer unmet needs for health-related services are associated with lower statewide rates of functional limitations in CSHCN. As health care costs increase and state revenues decrease, CSHCN are at increasing risk of losing access to required services. Were this to happen we might expect an increase in the proportion of CSHCN who experience significant functional limitations. Thus, a key challenge is to provide CSHCN access to the amount and quality of health-related care they require to achieve their potential.  相似文献   
998.
OBJECTIVE: To determine the incidence and treatment of lymphoceles after retropubic radical prostatectomy (RP). PATIENTS AND METHODS: Up to January 2004, 260 patients who had a retropubic RP in one institution by one surgeon were assessed retrospectively, using the patients' notes or the computerized results system to determine whether a lymphocele was suspected and then confirmed by imaging studies (computed tomography or ultrasonography). RESULTS: Nine patients developed symptomatic lymphoceles; eight of these were detected by imaging. Four lymphoceles required intervention while the remainder regressed spontaneously. No complications were reported in the group that was treated. CONCLUSION: The rate of symptomatic lymphocele formation was low after RP, with an overall incidence of 3.5%. Ultrasonography was effective in detecting lymphoceles and ultrasonographically guided percutaneous drainage an effective treatment.  相似文献   
999.
1000.
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