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991.
In order to gain insight into the relation between health and people's environment, literature published between 1985 and 1994 was gathered from several international databases. An introduction into existing theory regarding geographic disparities is presented: geographical drift and breeder hypotheses are discussed. This is followed by a critical review focusing on interaction effects of urbanicity and individual characteristics on health. This leads to two major conclusions. First, emphasis in past research has been primarily on urban constraints rather than opportunities. Positive aspects of urban living are often insufficiently appreciated. Second, positive and negative environmental aspects have an effect on health that is often dependent on individual characteristics. The extent to which the environment exerts influence on a person's health is dependent on that person's individual characteristics. These conclusions are relevant only for further developing the breeder hypothesis, however. Large scale individual based longitudinal data should be studied in order to gain more insight into the relative importance of the geographical drift hypothesis. 相似文献
992.
H Sano HK Uhthoff DS Backman JA Brunet G Trudel B Pham H Ishii 《Canadian Metallurgical Quarterly》1998,80(4):720-725
We examined macroscopically and microscopically 55 cadaver rotator-cuff tendons attached to their humeral heads to determine the distance between the edge of the articular cartilage and the tendon insertion of the supraspinatus (the width of the sulcus) and the score of regressive changes at the sulcus. In 33 specimens we measured the tensile strength. The width of the sulcus was correlated with the score of regressive changes and with the ultimate tensile strength of the supraspinatus tendon. The width of the sulcus correlated positively with the score of regressive changes (r = 0.66, p < 0.0001), but there was a negative correlation between the latter and the ultimate tensile strength (r = -0.81, p = 0.001) and between the width of the sulcus and the ultimate tensile strength (r = -0.74, p = 0.004). We believe that the width of the sulcus is a simple and useful clinical indicator of the integrity and the tensile strength of the supraspinatus tendon. 相似文献
993.
SB King W Yeh R Holubkov DS Baim G Sopko P Desvigne-Nickens DR Holmes MJ Cowley MG Bourassa J Margolis KM Detre 《Canadian Metallurgical Quarterly》1998,31(3):558-566
OBJECTIVES: We sought to compare outcomes of patients treated in the National Heart, Lung, and Blood Institute (NHLBI) Percutaneous Transluminal Coronary Angioplasty (PTCA) and New Approaches to Coronary Intervention (NACI) registries. BACKGROUND: Coronary angioplasty has numerous shortcomings. New devices for performing coronary interventions have been introduced in an effort to improve clinical outcomes. METHODS: Under the sponsorship of the NHLBI, a registry of consecutive patients treated with PTCA during 1985 to 1986 was established. In 1990, the NHLBI funded a second registry, the NACI. The two registries used the same data coordinating center to collect detailed baseline and follow-up information. RESULTS: Patients enrolled in the NACI registry were older, had undergone more previous bypass surgery procedures and had more stenoses located in bypass grafts than patients in the NHLBI PTCA registry. Procedural success was achieved in 72.1% and 82.6% of patients in the PTCA and NACI registries, respectively; however, in-hospital and 1-year mortality rates were 1.0% versus 1.8% and 3.1% versus 5.9% for the PTCA versus NACI registries, respectively. After risk adjustment, there was no difference in 1-year mortality. Rates of target lesion revascularization (TLR) were 21.5% for the PTCA registry and 24.2% for the NACI registry. NACI registry patients had a higher risk for TLR and the composite end point of death, myocardial infarction or revascularization (relative risk 1.28 and 1.23, respectively). However, the NACI registry patients who received stents tended to have a lower adjusted TLR rate. CONCLUSIONS: This comparative study found no overall superiority of these newer devices in terms of patient survival or freedom from TLR after adjustment for baseline risk profiles. Although technologic improvements (especially improved stenting) continue, these observations highlight the importance of careful assessment of clinical results in the broad population of patients in whom interventions are used. 相似文献
994.
MD Holzman KL Reintgen DS Tyler TN Pappas 《Canadian Metallurgical Quarterly》1997,1(3):236-43; discussion 243-4
Laparoscopic evaluation of patients with suspected periampullary malignancies has been utilized more frequently in recent years. Its exact role with regard to staging and surgical bypass for palliation have yet to be clearly defined. To better define the role of laparoscopy in the evaluation and palliation of periampullary malignancy, a retrospective review of the Duke experience was carried out. Fifty-three patients with suspected pancreatic or periampullary malignancies were referred for surgical evaluation at Duke University Medical Center between 1993 and 1995. All patients underwent CT scanning and lesions were classified as resectable or unresectable based on previously established criteria. Patients either underwent laparoscopic evaluation (n = 30; 11 with laparoscopic palliation) or proceeded directly to celiotomy (n = 23). Charts were reviewed for postoperative course including complications, length of stay, and hospital costs. Although laparoscopy had a sensitivity of 93.3% for metastatic disease, CT scans accurately staged 86.8% of patients missing only one patient with peritoneal/hepatic disease. Based on these results, laparoscopy may not be beneficial for every patient with a suspected pancreatic malignancy. Retrospectively an attempt was made to determine which patients benefited from laparoscopy and which patients are best served by proceeding directly to open exploration. From these data we devised an algorithm that outlines an efficient and cost-effective approach for this patient population. 相似文献
995.
996.
BACKGROUND: Scintigraphy with 111In (indium-111)-oxine or 99mTechnetium-hexamethylpropyleneamine oxime (99mTc-HMPAO) labeled leukocytes has been used to differentiate brain abscess from brain tumor. However, there are false positive or false negative results from planar scintigraphic images. So a more specific and sensitive scintigraphic technique needs to be developed. METHODS: Planar and single photon emission computed tomography (SPECT) images were obtained and reviewed in 14 patients with intracerebral ring-enhancing lesions on computed tomography (CT) or magnetic resonance imaging (MRI). In all patients, diagnosis was confirmed by histopathologic examination. The effect of steroids or antibiotics on scintigraphic finding was examined. RESULTS: Abscess was confirmed in six patients, tumor in six, tuberculoma and cysticercosis in one each, respectively. In all the patients with abscess, SPECT showed increased focal activity irrespective of steroid or antibiotic therapy. Increased radioactivity, which could not be detected on planar images, could be identified in two patients with abscess. In three of the six patients with tumor, radiolabeled leukocytes did not accumulate in the tumor. In the other three patients with tumor, SPECT showed focally increased activity that was less intense than the activity shown in the patients with abscess. CONCLUSIONS: 99mTc-HMPAO labeled leukocyte SPECT is useful for the differential diagnosis of intracerebral ring-enhancing lesions, and the use of steroids or antibiotics does not influence the sensitivity of SPECT. Diagnostic sensitivity of scintigraphy with labeled leukocytes could be improved by SPECT in addition to planar image. 相似文献
997.
998.
999.
1000.
KP Pages JE Russo DK Wingerson RK Ries PP Roy-Byrne DS Cowley 《Canadian Metallurgical Quarterly》1998,49(9):1187-1192
OBJECTIVE: The study examined predictors of discharge against medical advice (AMA) and outcomes of psychiatric patients with AMA discharges, as measured by poorer symptom ratings at discharge and higher rates of rehospitalization. METHODS: A total of 195 patients discharged AMA from general hospital psychiatric units were compared retrospectively with 2,230 regularly discharged patients. AMA status was defined as signing out against medical advice, being absent without leave, or being administratively discharged. All patients received standardized assessments within 24 hours of admission and at discharge. Demographic characteristics, psychiatric history, DSA-IV psychiatric and substance use diagnoses, and scores on an expanded 32-item version of the Psychiatric Symptom Assessment Scale were compared. RESULTS: The groups did not differ in primary psychiatric diagnoses. Patients discharged AMA were significantly less likely to be Caucasian or to be functionally impaired due to physical illness. They were more likely to live alone, have a substance use diagnosis, use more psychoactive substances, and have more previous hospitalizations. Patients discharged AMA had significantly shorter lengths of stay, higher rehospitalization rates, and more severe symptoms at discharge, even when length of stay was taken into account. The differences between the groups in male gender and young age were better accounted for by a greater likelihood of substance abuse in these groups. CONCLUSIONS: The results suggest a profile of patients who may be discharged AMA. Such patients have worse outcomes and are more likely to be high utilizers of inpatient resources. Aggressive identification of patients likely to be discharged AMA and early discharge planning for appropriate outpatient treatment are recommended. 相似文献