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91.
This article summarizes key findings from evaluation and research studies that have received financial support from the HIV/AIDS Bureau of the Health Resources and Services Administration or from Ryan White Comprehensive AIDS Resources Emergency (CARE) Act grantees. These studies suggest that the CARE Act has improved but not equalized service accessibility, quality, and outcomes for different populations living with HIV disease. Evaluations of access to highly active antiretroviral therapy (HAART) found that uninsured patients, women, people of color, and injection drug users waited much longer than others to receive the new therapies. These disparities were not uniform across study sites, suggesting that clinic characteristics and geographic location have a major influence on prescribing patterns. Once patients gained access to HAART, health insurance status made little difference in clinical outcomes. 相似文献
92.
目的使用非线性成长率理论分析人眼视力发展规律。方法使用高斯光学及成像方程推导出两个参数:屈光状态改变率(M)及眼轴成长率(N),用以预测MOS(初始近视)、年龄(A^*)及其后视力的发展情况。结果当有效焦距F=(21-22)、密码M=(2.67—2.9)(D/mm)时,此计算值符合实验平均值(2.7)。当年龄A^*=(3,6)岁的屈光度变化已知时,我们计算其MOS预测年龄为A^*=(7.3,21.8)岁(在不同条件下)。此值反比于M值在A=6及A=3的比值或N=N—N^*,即非正视态及正视态的眼轴成长率之差。本理论也可用来预测在年龄A=25时的近视度,分别为D=-14及-0.49的上述两例情况,同时也能分析Lain等人的测量值(由出生到青年期的视力发展情况)。结论本理论可预测MOS、其后发展情况及其符合实验值(M)。使用成长率差值(dN)比使用L/rl比值能更准确地预测MOS。 相似文献
93.
LT Lucato AM McKinney J Short M Teksam CL Truwit 《Journal of Medical Imaging and Radiation Oncology》2006,50(4):364-368
A 35‐year‐old woman presented with neurotoxicity correlated to an i.v. regimen of 5‐fluorouracil as episodes of acute confusional state and abnormalities of symmetrically restricted diffusion in the periventricular white matter and corpus callosum. On discontinuing the medication, the areas of severely restricted diffusion had entirely resolved, with minimal residual T2 signal abnormality. In this case, immediate discontinuation of the chemotherapeutic agent apparently reversed the patient's symptoms and findings on MRI. The scant information available in the published literature regarding this phenomenon is reviewed with regard to 5‐fluorouracil. 相似文献
94.
Patients with carcinoma of the biliary tract have a poor prognosis because the disease is often unresectable at diagnosis. Intraluminal brachytherapy has been reported as an effective treatment for localized cholangiocarcinoma of the biliary tract. The purpose of our study was to analyse the survival of patients treated with brachytherapy and make some recommendations regarding its use. Fifteen patients underwent brachytherapy via a trans-hepatic approach at the Royal Prince Alfred Hospital from 1983 to 1993. Eleven patients had low-dose rate brachytherapy and four patients had high-dose rate treatment. There were nine males and six females. The median age was 64 years. Other treatment included bypass procedures in two patients, endoscopic stents in 14 patients and external beam irradiation in one patient. The median survival was 12.5 months and 47% of the patients survived 1 year. The only complication reported was cholangitis which was seen in one patient. There did not seem to be any difference in survival or complications between low- and high-dose rate brachytherapy. We conclude that the addition of intraluminal brachytherapy after biliary drainage prolongs survival and is a safe and effective treatment, but patients still have a high rate of local failure, and further studies will be needed to address this problem. 相似文献
95.
Socioeconomic status and risk of adenocarcinoma of the oesophagus and cancer of the gastric cardia in Scotland 总被引:5,自引:0,他引:5
The incidence of oesophageal adenocarcinoma and gastric cardia cancer increased strikingly in Scotland between 1977 and 1996. In contrast to other cancers of the oesophagus and stomach, which showed a clear relationship with socioeconomic status, no trend was evident for oesophageal adenocarcinoma or gastric cardia cancer during 1987-1996. 相似文献
96.
McKinney PE 《Journal of toxicology. Clinical toxicology》2000,38(4):435-440
BACKGROUND: Ingestion of elemental lead foreign bodies is felt to have a low risk of clinically significant lead absorption unless gastrointestinal pathology and/or prolonged transit time are present. We present a case of ingestion of a large quantity of small diameter lead shot accompanied by rapid elevation of blood lead levels. CASE REPORT: A 5 1/2-year-old previously healthy girl was found eating the pellets from an ankle weight. She vomited and complained of abdominal pain. In the emergency department, she had no complaints and normal vital signs. An abdominal X-ray showed thousands of small, round, metallic density objects in the stomach. Her white blood cell count was 14,700/mm3, and the hemoglobin, mean corpuscular volume, free erythrocyte protoporphyrin, zinc protoporphyrin, biochemistry panel 21, and urinalysis were normal. She had no prior lead level for comparison. Whole-bowel irrigation was begun and she passed over 11 stools with pellets as well as other foreign bodies (erasers, bead, etc.) in the first 24 hours. Pellets were still seen on X-ray the following day so she received a high-fiber diet and bisacodyl tablets 10 mg/d. On hospital day 2, her admission blood lead (drawn 13 hours after ingestion) was reported as 57 microg/dL (2.7 microm/L) and chelation was begun with oral 2,3-dimercaptosuccinic acid 10 mg/kg 3x/d for 5 days, then 2x/d for 14 days. Her peak measured lead level was 79 microg/dL approximately 36 hours after ingestion. She excreted 2,273 microg lead in the urine during her first 24 hours of chelation. Her blood lead dropped to 14.3 microg/dL by the end of chelation. She did not develop any apparent signs of lead poisoning. CONCLUSION: Acute elevations of blood lead concentrations may occur rapidly after ingestion of multiple small elemental lead objects. 相似文献
97.
Data were collected prospectively from 116 children younger than 2 years old who were seen at the Duke Pediatric AIDS Clinical Trials Unit for known human immunodeficiency virus seropositivity. Forty-six (40%) of these children were human immunodeficiency virus-infected and 70 were not infected. Using 3-month blocks, 10th, 50th and 90th percentiles were calculated for the CD4+ and CD8+ cell counts, percentage of lymphocytes positive for CD4 and CD8 and T4:T8 ratios. Results from the infected and uninfected children were compared. By 3 to 6 months of age the infected patients had significantly lower CD4+ counts, percentage CD4+ cells and T4:T8 ratios, whereas the percentage of CD8+ lymphocytes was significantly higher. Absolute CD8+ counts were approximately the same in infected and uninfected children through age 2 years. Most infected children had one or more abnormal lymphocyte subset results (less than the 10th percentile for uninfected patients) by age 2: 83% had an abnormal CD4+ percentage; 78% had an abnormal T4:T8 ratio; and 67% had an abnormal CD4+ count. All 13 children who had an opportunistic infection (at any age) had an abnormal CD4+ percentage before age 2 years, and 12 of 13 had a low absolute CD4+ count or T4:T8 ratio. Among patients who died 10 of 11 had 1 or more low CD4+ count, 9 of 11 had an abnormal CD4+ percentage and 8 of 11 an abnormal T4/T8 ratio. 相似文献
98.
F E Alexander P A McKinney K C Moncrieff R A Cartwright 《British journal of cancer》1992,65(4):583-588
A retrospective population-based case-control interview study has been conducted in three distinct areas in the north of England where local excesses of children with leukaemia have been reported. A total of 109 cases of childhood (0-14 years at diagnosis) leukaemia and non-Hodgkin's lymphoma who were born in one of the study areas and diagnosed there between 1974 and 1988 were included in the study. One control per case was matched on sex, date-of-birth and health district of birth. The objective was to compare residential histories of cases and controls and in particular to determine whether case children had lived in the same place at the same time more often than controls. The residential distance between two children was taken to be the smallest geographical distance between homes they had 'occupied' simultaneously for a period of at least 6 months between conception and diagnosis. Case children were more likely than expected to have other cases as their nearest neighbours by residential distance (observed = 69, expected = 54.5, P = 0.006). A detailed examination of the nearest neighbour pattern permits the generation of further specific hypotheses. These suggest that persistent infection established in utero or early infancy may be involved in the development of some cases of childhood leukaemia. Horizontal transmission of the agent(s) within small communities may occur but there is no evidence of direct contact between cases. 相似文献
99.
100.
Uterine leiomyomas in the infertile patient: preoperative localization with MR imaging versus US and hysterosalpingography 总被引:2,自引:0,他引:2
Eleven women with a history of infertility and uterine leiomyomas underwent magnetic resonance (MR) imaging of the pelvis prior to myomectomy. Nine also underwent preoperative pelvic ultrasonography (US), and ten underwent hysterosalpingography. All studies were interpreted prospectively by independent observers. With each imaging modality, the location (one of 11 anatomic segments), size, and appearance of detected uterine leiomyomas were determined and compared with surgical and histologic findings. Among the nine patients who underwent both MR and US, the sensitivity (85%) and accuracy (94%) of MR imaging for abnormal segments was significantly better than that of US (sensitivity = 69%, P = .015; accuracy = 87%, P = .043). For the ten patients who underwent both MR and hysterosalpingography, the sensitivity (91%) and accuracy (96%) of MR imaging was better than that of hysterosalpingography (sensitivity = 18%, P = .0005; accuracy = 72%, P = .0005). The specificities of the three modalities did not significantly differ (100%, 97%, and 98% for MR, US, and hysterosalpingography, respectively). These data suggest that MR imaging is superior to US or hysterosalpingography for preoperatively locating uterine leiomyomas. 相似文献