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121.

Background  

Studies carried out in the community enable researchers to understand access to medicines, affordability, and barriers to use from the consumer's point of view, and may stimulate the development of adequate medicines policies. The aim of the present article was to describe methodological and analytical aspects of quantitative studies on medicine utilization carried out at the household level.  相似文献   
122.
Objective : To determine the approach to identifying neonatal hypoglycaemia and the definition of neonatal hypoglycaemia used by neonatal paediatricians in Australian Level 3 neonatal intensive care units (NICU).
Methodology : A questionnaire was sent to the 101 neonatal paediatricians in the 22 Level 3 NICU in Australia asking their method of screening for, and definition of, neonatal hypoglycaemia.
Results : Responses were received from 70 neonatal paediatricians, including all 22 directors. A bedside glucose meter is used in 19 of 22 NICU to screen for hypoglycaemia, whilst one NICU uses a glucose analyzer and another NICU uses a visual colour comparison method. One NICU does not screen, but has blood glucose measured in a satellite laboratory. If the screening method suggests hypoglycaemia, 62 of 63 neonatal paediatricians proceed to blood glucose determination in a laboratory, mostly using plasma samples. Based on the laboratory measurement, the definition of neonatal hypoglycaemia ranged from <1.1 to 3.0 mmol/L.
Conclusions : The majority of neonatal paediatricians in Australian NICU screen for neonatal hypoglycaemia using a bedside glucose meter. There is a wide range in the definition of neonatal hypoglycaemia from <1.1 to 3.0mmol/L.  相似文献   
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125.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
126.
Thallium-201/technetium-99m pertechnetate subtraction scintigraphy of the parathyroid glands was performed in a prospective study of 33 patients who had undergone bilateral neck exploration for elevated serum calcium and serum parathyroid hormone levels. In 31 cases, the Tl-201/Tc-99m subtraction technique yielded an overall sensitivity of 81%, specificity of 99%, and accuracy of 94% for identifying solitary parathyroid adenomas. Tl-201/Tc-99m subtraction scintigraphy correctly identified 73% of parathyroid adenomas weighing less than 499 mg, 79% of those weighing 500-1,499 mg, and 100% of adenomas weighing more than 1,500 mg. In a subgroup of 24 patients with solitary parathyroid adenomas who underwent both scintigraphy and high-resolution sonography, the sensitivity, specificity, and accuracy of both procedures were similar.  相似文献   
127.

Background  

To prospectively evaluate the efficacy and safety of selective internal radiation (SIR) spheres in patients with inoperable liver metastases from colorectal cancer who have failed 5FU based chemotherapy.  相似文献   
128.
Goldberg David J.  MD  JD 《Dermatologic surgery》2005,31(10):1317-1322
BACKGROUND: Dermatologic surgical techniques have transformed cosmetic surgery over the last two decades. Many of the advances in cutaneous laser surgery, botulinum toxin injections, tumescent liposuction, and the latest filler agents have been evaluated on willing volunteers as part of organized trials under the auspices of an Institutional Review Board (IRB). OBJECTIVES: To review the developmental history of today's IRB and to provide relevance to cosmetic dermatologic research. RESULTS: Although an IRB must evaluate the "voluntariness" of a proposed research protocol, the risk-benefit ratio, particularly of elective cosmetic dermatologic surgical human studies, is of even greater importance. CONCLUSION: As more dermatologic surgeons become involved in clinical research, an understanding of the function and purpose of the IRB has become increasingly important. Research relating to cosmetic dermatologic procedures raises challenging and perplexing problems for an IRB.  相似文献   
129.
Management of asymptomatic malposed third molars is a controversial topic. As a result, many malposed or mildly pathologic third molars are not removed. Historical pro and con arguments regarding removal centered around cost and the aspects of the surgical removal itself. Current epidemiology and medical advances address issues not considered before. There is a large growth of the aging population (over 40 years). More and more of these elderly patients are requiring third molar removal. Over a five-year period, 1997-2002, the incidence almost doubled to 17.9 percent. This age category is known to be high risk for third molar surgery. An equally or higher risk is the rapidly growing number of patients seeking third molar surgery who are moderately severely medically compromised. This paper reviews how this lack of consensus results in delayed removal of malposed third molars in this population. Preventive dental concepts, removing compromised third molars earlier, would eliminate the high risk to this aging population.  相似文献   
130.
OBJECTIVE: To update the authors' experience with intraductal papillary mucinous neoplasms (IPMNs) of the pancreas. BACKGROUND DATA: IPMNs are intraductal mucin-producing cystic neoplasms of the pancreas with clear malignant potential. Since the authors' 2001 report, the number of IPMNs resected at our institution has more than doubled, providing an opportunity to define the clinical features of this distinct neoplasm. METHODS: All patients undergoing pancreatic resection for an IPMN at the Johns Hopkins Hospital between January 1987 and March 2003 were evaluated. Noninvasive IPMNs were classified as "adenoma," "borderline," or "carcinoma-in situ" (CIS) depending on the degree of dysplasia within the specimen. Invasive cancers were classified as tubular, colloid, mixed, or anaplastic types. Pathology was retrospectively reviewed to identify main-duct or branch-duct origin of the tumors. Long-term overall survival for patients having IPMNs with invasive cancer was compared with those patients having IPMNs without an invasive component. RESULTS: Between January 1987 and March 2003, inclusive, 136 pancreatic resections were performed for patients with IPMNs, with 78 resections performed since January 2001. The mean age of the patients was 66.8 +/- 1.1 years, with 57% being male and 89% white. Pancreaticoduodenectomy was performed in 71% of patients, total pancreatectomy in 15%, distal pancreatectomy in 12%, and central pancreatic resection in 2%. IPMNs without evidence of invasive cancer were identified in 62% (n = 84) of patients (17% adenoma, 28% borderline, or 55% CIS). The remaining 38% (n = 52) of patients had IPMNs with associated invasive cancer (60% tubular, 27% colloid, 7% mixed, and 6% anaplastic). The mean age of patients with IPMN adenoma was 63.2 years, 66.7 years for those with borderline/CIS IPMNs, and 68.1 years for those with invasive cancer (P = 0.08, adenomas vs. invasive cancer). In those patients with invasive cancers, 15% had invasive cancer at the final surgical margin, 23% had IPMN without invasive cancer at the margin, and 54% had lymph node metastases. Residual IPMN was identified at the neck or uncinate margin in 24% of patients with noninvasive IPMNs. The overall 5-year survival for patients having IPMNs without invasive cancer was 77% (several deaths secondary to metachronous invasive cancer), compared with 43% in those patients with an invasive component (P < 0.0001). There were no differences in survival when comparing adenomas, borderline neoplasms, and CIS. Similarly, there were no statistically significant differences in survival when comparing branch-duct, main-duct, and combined variants; however, the branch-duct variants were more often noninvasive. For those patients with invasive IPMNs, 2-year survival was 40% when margins were positive for invasive cancer or for IPMN without invasive cancer, and 60% when margins were tumor-free (P = 0.15). Those patients with colloid carcinomas (n = 14) had improved survival compared with those with tubular carcinomas (n = 31), with 5-year survival rates of 83% and 24%, respectively. IPMN recurrences and deaths from cancer occurred in patients with both invasive and noninvasive IPMNs at initial resection. CONCLUSIONS: IPMNs continue to be recognized with increasing frequency. Five-year survival for those patients following resection of IPMNs with invasive cancer (43%) is improved compared with those patients with resected pancreatic ductal adenocarcinoma in the absence of IPMN (averages 15%-25%). Survival following resection of IPMNs without invasive cancer (regardless of degree of dyplasia) is good, but recurrent disease in the residual pancreas suggests that long-term surveillance is critical. Based on the age at resection data, there appears to be a 5-year lag time from IPMN adenoma (63.2 years) to invasive cancer (68.1 years).  相似文献   
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