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71.
The ability of various strategies to identify patients with gastroesophageal reflux disease (GERD) and the relative economic impact on disease management programs for GERD were studied. A telephone interview was conducted of a random sample of patients enrolled in any of three health plans in a 100,000-member managed care organization who had either a pharmacy claim or an encounter claim during 1997. The telephone interview identified patients with GERD and served as the standard by which the sensitivity, specificity, and predictive values of the following patient-identification strategies were compared: (1) telephone interview, (2) chart review, (3) use of encounter claims, (4) use of pharmacy claims, (5) use of both encounter claims, and pharmacy claims, and (6) use of encounter claims or pharmacy claims. Conservative estimates of costs and projected savings were then used to model the potential return on investment of the strategies. A total of 1186 patients completed the telephone interview, of whom 390 (33%) met the case definition of GERD. The most sensitive method for identifying patients with GERD was using either pharmacy or encounter claims (26%). The most specific strategy with the highest positive predictive value (PPV) (87%) was using both pharmacy and encounter claims, but this approach had a case-detection rate of only 3%. Encounter claims were significantly more sensitive than pharmacy claims and yielded a higher estimate of prevalence. The telephone interview identified the most subjects who could have benefited from a disease management program and cost 84% less than chart review. While use of administrative data (pharmacy and encounter claims) was the least costly strategy, it identified 74% fewer patients expected to benefit from disease management. The efficiency of disease management programs for GERD may depend on the method of patient identification, which in turn may depend on whether PPV or negative predictive value (NPV) should be maximized. If there is a need to identify all cases (i.e., sensitivity and NPV are most important), then telephone interview may provide the greatest opportunity for disease management with the greatest return on investment, but at the expense of enrolling many patients who may not benefit.  相似文献   
72.
Magnetic resonance (MR) imaging was performed on 14 patients with histologically proved osteosarcoma (mean age, 14.4 years). There was excellent correlation of intramedullary tumor extent as determined with MR imaging and pathologic examination (r = 99%). This was facilitated by the presence of a chemical shift artifact at the tumor-marrow interface on the T1-weighted images. The correlation between CT and pathologic findings was not as good (r = 84%). In a single patient, however, a 10-cm length of sclerotic bone was incorrectly interpreted as being tumor. If this case is excluded, the correlation between CT and pathologic findings improves significantly (r = 96%). T2-weighted images were optimal in demonstrating soft-tissue bulk and breach of the epiphysis or cortex. Vascular involvement was also readily defined. The T2 value of the tumor soft-tissue component decreased in patients who were deemed to have responded well to therapy. Two patients with very high T2 values after chemotherapy developed wide-spread metastatic disease and died. Phosphorus-31 MR spectroscopy of five patients with osteosarcoma showed elevated levels of phosphomonoesters (PMEs), inorganic phosphate (Pi), and phosphodiesters (PDEs). PME and PDE peak areas decreased in three patients after chemotherapy, while Pi peak areas increased.  相似文献   
73.
Two cases of severe hemolytic disease of the newborn due to c-isoimmunization are presented. Both women were multiparous, had previous blood transfusion and high maternal titers of anti-c (1:1024 and 1:4036, respectively).  相似文献   
74.
OBJECTIVES: To establish the feasibility of examining the subclavian artery at 11 + 0 to 13 + 6 weeks of gestation, and to determine the prevalence of aberrant right subclavian artery (ARSA) in chromosomally normal and chromosomally abnormal fetuses. METHODS: Fetal echocardiography was performed prospectively in 516 patients before chorionic villus sampling at 11 + 0 to 13 + 6 weeks of gestation. Transabdominal sonography was carried out, and color flow mapping was used to identify the right subclavian artery and determine whether this was normal or aberrant (ARSA). Second-trimester fetal echocardiography was also carried out in a subgroup of 183 fetuses. RESULTS: The median gestational age was 12 weeks and the median crown-rump length was 68 mm. Successful assessment of the right subclavian artery was achieved in 425/516 (82.4%) cases and the rate of failure to do so was significantly associated with decreasing fetal crown-rump length (r = 0.174, P < 0.001) and increasing maternal body mass index (r = 0.275, P < 0.001). An ARSA was observed in 2/353 (0.6%) fetuses with a normal karyotype, in 4/51 (7.8%) cases with trisomy 21 and in 2/20 (10.0%) with other chromosomal defects. In a subgroup of 183 fetuses examined in both the first and second trimester there were three cases of ARSA observed at both scans and an additional case in which ARSA was detected only at the second scan. CONCLUSIONS: Assessment of the position of the right subclavian artery is feasible at the 11 + 0 to 13 + 6-week scan and ARSA is more common in chromosomally abnormal than normal fetuses. However, ARSA in the first trimester is unlikely to be a useful marker of trisomy 21.  相似文献   
75.
76.
Low back pain continues to affect a significant proportion of the younger, working population between 35 and 45 years of age. An important study has correlated macroscopic and microscopic intervertebral disc alterations starting in the second decade of life with oxidative stress manifested by the presence of N-(carboxylmethyl)lysine. Job satisfaction remains a strong predictive factor for the identification of individuals with acute back pain who will develop chronic pain. Patients with pyogenic vertebral osteomyelitis may have an increase in their erythrocyte sedimentation rate during the first 2 weeks of antibiotic therapy without requiring surgical intervention. Magnetic resonance imaging enhancement of migrated disc fragments identifies individuals who are likely to resolve sciatica without surgical intervention. As many as 25% of individuals with low back pain are symptomatic at 12 months, in contradistinction to the dictum of resolution of pain in 2 months. Nonsteroidal anti-inflammatory drugs and muscle relaxants are a very effective combination for the effective treatment of acute low back pain. A majority of chiropractic manipulations are performed for inappropriate indications.  相似文献   
77.
Bilateral independent median nerve somatosensory evoked potentials (SEP) were obtained in 15 patients with inflammatory arthritis of the cervical spine. Limitation of neck motion, neck pain, abnormal neurologic findings, and atlantoaxial subluxation were evaluated. Ten of 15 patients had abnormal SEP associated with subluxation in 9. Neurological signs specifically localizable to the central nervous system (CNS) were present in only 2 of the 10 patients. SEP were normal in the remaining 5 patients despite the presence of nonspecific neurological signs including atrophy of the intrinsic muscles of the hands and atlantoaxial subluxation determined by radiographic evaluation in 3 of 5 patients. Our study demonstrates the value of SEP in the evaluation of CNS function when findings on examination and radiographs may not conclusively document spinal cord impairment.  相似文献   
78.
The effect of a synthetic thymic humoral factor, THF-gamma 2, on the immune competence of T-cells was investigated in vitro on lymphocytes from human cord blood (UCBL). It was found that preincubation of UCBL with THF-gamma 2 caused an increase in the percentage of cells expressing the CD4 or the CD8 differentiation antigens, but did not affect the percentage of CD3 cells. The effect of THF-gamma 2 on PHA-induced IL-2 secretion was also studied and found that a 3hr preincubation with THF-gamma 2, prior to suboptimal PHA stimulation caused an increase in the IL-2 activity of the treated UCBL cultures. This effect was THF-gamma 2 dose dependent with an optimum in the range of 300-600 ng/ml and was not influenced by irradiation of the UCBL. These results indicate that THF-gamma 2, a synthetic octapeptide, modulates the immune state and response of human umbilical cord blood lymphocytes.  相似文献   
79.
A transparent polyurethane dressing (Omiderm) for free flaps is presented. Considering the importance of reliable flap monitoring postoperatively, this synthetic membrane allows for constant ability to observe the flap, assess the capillary filling, and detect the blood flow with an ultrasound Doppler device.  相似文献   
80.
The effects of magnetic resonance (MR) pulse sequences and timing parameters on tumor-liver contrast were studied in an animal model of metastatic liver cancer. Six spin-echo (SE), three inversion-recovery (IR), and four gradient-echo (GRE) sequences were evaluated at 0.6 T before and after injection of super-paramagnetic iron oxide. GRE techniques, irrespective of echo time and flip angle, showed the greatest change in signal intensity (enhancement) of the liver after administration of iron oxide. Single-acquisition GRE sequences (16 seconds) matched the contrast-to-noise ratio (C/N) performance of the most effective 6.4-minute SE sequences. Multiexcitation GRE sequences showed tumor-liver C/Ns per unit time that were significantly (P less than .05) higher than those achieved with SE and IR sequences. GRE sequences, which recruit intravoxel dephasing as an additional source of transverse relaxation enhancement (T2*), show a higher C/N per unit time and in this respect seem superior to SE and IR sequences for MR imaging with superparamagnetic iron oxide.  相似文献   
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