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1.
In this paper, a new image analysis based method for electrospun nanofiber diameter measurement has been presented. The method was tested by a simulated image with known characteristics and a real web. Mean (M) and standard deviation (STD) of fiber diameter obtained using this method for the simulated image were 15.02 and 4.80 pixels respectively, compared to the true values of 15.35 and 4.47 pixels. For the real web, applying the method resulted in M and STD of 324 and 50.4 nm which are extremely close to the values of 319 and 42 nm obtained using manual method. The results show that this approach is successful in making fast, accurate automated measurements of electrospun fiber diameters.  相似文献   
2.
BACKGROUND: Emphasis on ensuring women's access to preventive health services has increased over the past decade. Relatively little attention has been paid to whether the sex of the physician affects the rates of cancer screening among women. We examined differences between male and female physicians in the frequency of screening mammograms and Pap smears among women patients enrolled in a large Midwestern health plan. METHODS: We identified claims for mammography and Pap tests submitted by primary care physicians for 97,962 women, 18 to 75 years of age, who were enrolled in the health plan in 1990. The sex of the physician was manually coded, and the physician's age was obtained from the state licensing board. After identifying a principal physician for each woman, we calculated the frequency of mammography and Pap smears for each physician, using the number of women in his or her practice during 1990 as the denominator. Using unconditional logistic regression, we also calculated the odds ratio of having a Pap smear or mammogram for women patients with female physicians as compared with those with male physicians, controlling for the physician's and the patient's age. RESULTS: Crude rates for Pap smears and mammography were higher for the patients of female than male physicians in most age groups of physicians. The largest differences between female and male physicians were in the rates of Pap smears among the youngest physicians. For the subgroup of women enrolled in the health plan for a year who saw only one physician, after adjustment for the patient's age and the physician's age and specialty, the odds ratio for having a Pap smear was 1.99 (95 percent confidence interval, 1.72 to 2.30) for the patients of female physicians as compared with those of male physicians. For women 40 years old and older, the odds ratio for having a mammogram was 1.41 (95 percent confidence interval, 1.22 to 1.63). For both Pap smears and mammography, the differences between female and male physicians in screening rates were much more pronounced in internal medicine and family practice than in obstetrics and gynecology. CONCLUSIONS: Women are more likely to undergo screening with Pap smears and mammograms if they see female rather than male physicians, particularly if the physician is an internist or family practitioner.  相似文献   
3.
Oxygenation is a major determinant of the physiological state of cultured cells. 19F NMR can be used to determine the oxygen concentration available to cells immobilized in a gel matrix by measuring the relaxation rate (1/T1) of perfluorocarbons (PFC) incorporated into the gel matrix. In calcium alginate gel beads without cells the relaxation rate (1/T1) of the trifluoromethyl group of perfluorotripropylamine (FTPA) varies linearly with oxygen concentration, with a slope of 1.26 +/- 0.15 x 10(-3) s-1 microM-1 and an intercept of 0.50 +/- 0.04 s-1. During perfusion with medium equilibrated with 95%/5% O2/CO2, changes in PFC T1s indicate that the average oxygen concentration was reduced from 894 +/- 102 microM in the absence of cells to 476 +/- 65 microM and 475 +/- 50 microM in the presence of 0.7 x 10(8) EMT6/Ro and RIF-1 murine tumor cells per milliliter of gel, respectively. The presence of 0.2 microliters of FTPA/ml of gel had no effect on the energy status of the cells as indicated by 31P NMR spectra. To calculate oxygen gradients within the beads from the average PFC T1 of the sample, a mathematical model was used assuming that oxygen is the limiting nutrient for cell metabolism and that the cellular oxygen consumption rate is independent of oxygen concentration. Data for EMT6/Ro cells were fit using experimentally determined perfusion parameters together with literature values for cell volume and oxygen consumption rate.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
Active cytomegalovirus (CMV) retinitis in patients with acquired immunodeficiency syndrome (AIDS) was treated with an intraocular sustained-release ganciclovir implant. A total number of 19 implants were performed in 15 eyes of 9 AIDS patients. The intraocular sustained-release ganciclovir was effective in preventing reactivation of CMV retinitis in 15 of the 19 implants, ineffective in 3, and undetermined in 1. All ineffective cases had been resistant to ganciclovir therapy before the implants. Vision after the therapy was maintained at better than 0.5 except for one eye. There were no serious ocular complications caused by the therapy. Among 5 patients with unilateral CMV retinitis, 2 unaffected eyes developed CMV retinitis during this therapy. In addition, another patient developed presumed CMV infection in other systemic organs. Based on these data, the intraocular sustained-release ganciclovir implant was considered to be useful for the treatment of CMV retinitis in AIDS.  相似文献   
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6.
McGovern  M. 《IT Professional》2002,4(3):52-54
Managing IT system security is a never-ending effort. Regardless of how well you secure a system today, new threats and issues will appear tomorrow. User support, IT staff enthusiasm, and management buy-in are critical assets for overcoming the constant barrage of threats. Unfortunately, there is no standard playbook that tells IT managers how to manage these relationships and focus them on security issues. Every IT staff must build its own strategy. The article outlines concepts to manage security. This list serves as a good source of ideas for how IT managers can use awareness to advance their security goals  相似文献   
7.
Supports T. R. Scott's (see record 1992-06990-001) idea of reorganization of academic psychology departments and asserts that the label of a particular department derives from more than the specialized knowledge that its faculty creates and communicates. However, Scott fails to address the consequences for undergraduate education under his proposed reorganization. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
PURPOSE: We describe a protocol designed to evaluate the use of twice daily radiation used together with cisplatin and 5 fluorouracil (5-FU) in the treatment of operable transitional cell carcinoma of the bladder with potential bladder preservation. MATERIALS AND METHODS: A total of 18 consecutive patients with T2-T4a bladder tumors underwent as complete a transurethral resection as possible, which was visibly complete in 14 cases. They then received twice daily radiation and infusion cisplatin and 5-FU during an induction phase. No therapy was given for 3 weeks, following which patients were reevaluated cystoscopically. Cases of clinical complete response by biopsy and cytology were consolidated with further chemotherapy/radiation using the same chemotherapeutic agents and radiation schedule. Patients who had incomplete responses were advised to undergo an immediate radical cystectomy. Of the 18 patients 15 subsequently received 3 cycles of adjuvant chemotherapy, consisting of methotrexate, cisplatin and vinblastine. Median followup for the entire group is 32 months. RESULTS: Of the 18 patients 14 had no detectable tumor after induction therapy. Of the 4 patients with persistent tumor 2 underwent radical cystectomy and 2 refused cystectomy, 1 of whom was treated with partial cystectomy and the other with consolidation chemotherapy/radiation. The actuarial overall survival at 3 years was 83%. The chance of a patient being alive at 3 years with a native bladder was 78%. No patient required cystectomy for hematuria or bladder shrinkage. Three patients in whom superficial tumors developed were treated successfully with bacillus Calmette-Guerin. Small bowel obstruction in 1 case was corrected surgically. CONCLUSIONS: This pilot study demonstrates a high rate of response to this combined chemotherapy/radiation regimen in conjunction with a visibly complete transurethral resection. Reevaluation after a short induction phase allows for the early selection of patients with persistent disease for radical cystectomy.  相似文献   
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McGovern  P.A. 《Electronics letters》1976,12(22):585-585
The characteristics of microwave measuring-grade point-contact detectors can be linearised over a wide dynamic range with a simple circuit with only one adjustable parameter for nonlinearity. The need for matching of detectors is also largely eliminated.  相似文献   
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