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31.
Fairbrother G Jain A Park HL Massoudi MS Haidery A Gray BH 《Journal of health care for the poor and underserved》2004,15(1):30-41
There is concern that churning in Medicaid excludes children from the accountability system for managed care because they may not meet the one-year continuous enrollment requirement. This study explores the effect of churning in measuring childhood immunization coverage rates under the current accountability system. Data were collected from administrative databases at the Centers for Medicaid and Medicare Services and 12 states with high Medicaid managed care penetration. On average in the 12 states only 39% of the children enrolled in one specific managed care plan met the continuous enrollment requirement. However, Centers for Medicaid and Medicare Services data showed that 78% of children were enrolled in Medicaid (but not the same plan) continuously for 12 months. Both plan-specific rates and overall Medicaid rates varied greatly across the states. Policies that result in churning mean that many vulnerable children fall outside of the accountability structure intended to assure that they receive necessary services. 相似文献
32.
Role of avian pathogenic Escherichia coli virulence factors in bacterial interaction with chicken heterophils and macrophages 总被引:6,自引:0,他引:6
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Mellata M Dho-Moulin M Dozois CM Curtiss R Lehoux B Fairbrother JM 《Infection and immunity》2003,71(1):494-503
Avian pathogenic Escherichia coli (APEC) cause extraintestinal disease in avian species via respiratory tract infection. Virulence factors associated with APEC include type 1 and P fimbriae, curli, aerobactin, lipopolysaccharide (LPS), K1 capsular antigen, temperature-sensitive hemagglutinin (Tsh), and an uncharacterized pathogen-specific chromosomal region (the 0-min region). The role of these virulence factors in bacterial interaction with phagocytes was investigated by using mutants of three APEC strains, each belonging to one of the most predominant serogroups O1, O2, and O78. Bacterial cell interaction with avian phagocytes was tested with primary cultures of chicken heterophils and macrophages. The presence of type 1 fimbriae and, in contrast, the absence of P fimbriae, K1 capsule, O78 antigen, and the 0-min region promoted bacterial association with chicken heterophils and macrophages. The presence of type 1 and P fimbriae, O78 antigen, and the 0-min region seemed to protect bacteria against the bactericidal effect of phagocytes, especially heterophils. The tested virulence factors seemed to have a limited role in intracellular survival for up to 48 h in macrophages. Generally, opsonized and nonopsonized bacteria were eliminated to the same extent, but in some cases, unopsonized bacteria were eliminated to a greater extent than opsonized bacteria. These results confirm the important role of type 1 fimbriae in promotion of initial phagocytosis, but nevertheless indicate a role for type 1 fimbriae in the protection of bacteria from subsequent killing, at least in heterophils. The results also indicate a role for K1 capsule, O78 antigen, P fimbriae, and the 0-min region in initial avoidance of phagocytosis, but demonstrate an additional role for O78 antigen, P fimbriae, and the 0-min region in subsequent protection against the bactericidal effects of phagocytes after bacterial association has occurred. 相似文献
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35.
Dopamine release and metabolism in the rat striatum: an analysis by 'in vivo' brain microdialysis 总被引:8,自引:0,他引:8
Brain microdialysis studies on the mechanisms underlying dopamine release in the rat striatum provide evidence that both exocytotic and carrier-dependent processes operate in vivo. While several releasers (potassium, veratrine, amphetamine, ouabain) utilize newly synthesized stores of dopamine, tyramine is uniquely sensitive to depletion of vesicular storage by reserpine. Extracellular DOPAC is closely associated with the newly synthesized pool of dopamine and experiments with selective monoamine oxidase inhibitors suggest that DOPAC is formed mainly by MAO-A. Recent work on the two dopamine receptors suggest that release by different mechanisms may selectively activate D1 or D2 receptor subtypes. 相似文献
36.
Dr. Karla L. Hanson PhD Dr. Gary C. Butts Dr. Stephen Friedman Dr. Gerry Fairbrother 《Journal of urban health》2001,78(1):112-124
Private practice physicians in New York City’s poorest neighborhoods are typically foreign trained, have generally substandard
clinical practices, and have been accused of rushing Medicaid patients through to turn a profit. However, they also represent
a sizable share of physician capacity in medically underserved neighborhoods. This article documents the level of credentials,
systems, and immunization-related procedures among these physicians. Furthermore, it assesses the relationship between such
characteristics and childhood immunization rates. The analysis utilizes a cross-sectional comparison of immunization rates
in 60 private practices that submitted 2,500 or more Medicaid claims for children. Immunization data were gathered from medical
records for 2,948 randomly selected children under 3 years of age. Half of sampled physicians were board certified (55%),
and half were accepted by the Medicaid P referred P hysicians and Children (P P AC) program (51.7%). Of physicians, 43% saw
patients only on a walk-in basis, while only 17% scheduled the next appointment while the patient was still in the office.
There were 75% of the physicians who reported usually immunizing at acute care visits. Immunization rates were higher among
PPAC physicians compared to others (41% vs. 29% up to date for diphtheria and tetanus toxoids and pertussis [DTP]/Haemophilus influenzae type b [Hib], polio, and measles-mumps-rubella [MMR], P=.01), and board-certified physicians showed a trend tovard better immunization rates (39% vs. 30%, P=.07). Physicians who reported usually immunizing at acute care visits also had higher rates than those who did not (38% vs.
27%, P=.05). Scheduling a date and time for the next immunization showed a trend toward association with immunization coverage (37%
vs. 28%, P=.10). Private practice physicians who provide high volumes of care reimbursed by Medicaid have improved their credentials
and affiliations over time, thereby expanding reimbursement options. Credentials and affiliations were at least as effective
in distinguishing relatively high- and low-performing physicians, as were immunization-related practices, suggesting that
they are useful markers for higher quality care. The relative success of the P P AC programshould informefforts to inprove
the capacity and quality of primary care for vulnerable children. Appointment and reminder systems that effectively manage
the flow of children back into the office for immunizations and the vigilant use of acute care visits for immunizations go
hand in hand. Opportunity exists for payers and plans to encourage and support these actions.
This research was supported by the Centers for Disease Control and Prevention through contract 9775565 with the New York City
Department of Health. 相似文献
37.
38.
Spondylometaphyseal dysplasia, corner fracture type: a heritable condition associated with coxa vara
Langer LO Jr; Brill PW; Ozonoff MB; Pauli RM; Wilson WG; Alford BA; Pavlov H; Drake DG 《Radiology》1990,175(3):761-766
The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara. 相似文献
39.
Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal. 相似文献
40.
CA Gateley FRCS WG Lewis FRCS DE Sturdy MS FRCS 《International journal of clinical practice》1993,47(5):276-277
SUMMARY Clinically significant symptoms due to gastrointestinal metastases from primary lung cancers is rare. A case of life-threatening lower gastrointestinal haemorrhage secondary to metastatic squamous cell carcinoma of the lung is reported. Previous reports of such metastases are reviewed, with reference to management and prognosis. After resection of colonic metastases from squamous cell lung cancer, survival is similar to that for primary disease. It is suggested that patients with known or suspected squamous cell lung cancer presenting with lower gastrointestinal symptoms be managed as aggressively as those with no previous history of disease. 相似文献