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41.
Summary The prevalence and distribution of medial arterial calcification was assessed in the feet of four subject groups; 54 neuropathic diabetic patients with previous foot ulceration (U), median age 60.5 (50.5–67 interquartile range) years, duration of diabetes 19.5 (9.9–29.9) years; 40 neuropathic diabetic patients without a foot ulcer history (N), age 68 (62–73) years, duration of diabetes 14.0 (8.0–28.0) years; 43 non-neuropathic diabetic patients (NN), age 60.5 (52–68.5) years, duration of diabetes 14.0 (8.0–28.0) years and 50 non-diabetic control subjects, age 62.5 (53.7–70) years. A single radiologist graded medial arterial calcification as absent, mild or severe, at the ankle, hind-foot, mid-foot, metatarsals and toes on standardised plain lateral and antero-posterior foot radiographs taken by a single radiographer. Diabetes history, vibration perception threshold, ankle systolic pressure and serum creatinine were also assessed. Medial arterial calcification was significantly greater (total score 18 [3–31]) in neuropathic diabetic patients with previous ulceration (U vs N p<0.01, U vs NN p<0.001). Non-neuropathic diabetic patients did not have significantly higher arterial calcification scores than age-matched non-diabetic control subjects. Medial arterial calcification correlated with vibration perception threshold (r=0.35), duration of diabetes (r=0.32) and serum creatinine (r=0.41), (all p<0.01). Logistic regression models showed vibration perception and duration of diabetes to predict the probability of any calcification. Serum creatinine level was added to predict severe calcification. Ordered categorical modelling confirmed that medial arterial calcification was significantly heavier at the ankle than the toes for all groups, odds ratio 4.35 (2.94–6.43, 95% confidence intervals), (p<0.01). Ankle systolic pressure and ankle-brachial pressure index were significantly associated with degree of arterial calcification, r=0.40 and r=0.35, respectively, (both p<0.01) in diabetic patients. However, arterial calcification was present in more than one-third of patients with an ankle-brachial pressure index of less than 1.0. In conclusion, although ankle pressures correlate with the degree of arterial calcification, medial arterial calcification may be present in patients with low ankle systolic pressures, which may be falsely elevated even at normal values. This finding may provide a rationale for the use of toe rather than ankle pressure measurements in diabetic patients, particularly those with peripheral neuropathy, and this hypothesis should be directly tested in future studies.  相似文献   
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43.
1. Two week chronic administration of trimipramine increased the brain concentration and metabolism of dopamine and 5-hydroxytryptamine. 2. The treatment also produced a reduction in dopamine D2 and 5-hydroxytryptamine 5-HT2 receptors but no change in tryptamine binding was observed. 3. These findings suggest that trimipramine induces adaptive changes in dopamine and 5-hydroxytryptamine neurotransmission.  相似文献   
44.
Necrobiosis lipoidica diabeticorum: a clinicopathologic study   总被引:1,自引:0,他引:1  
Necrobiosis lipoidica diabeticorum is an unusual dermatologic condition with a characteristic clinical appearance and a clear association with diabetes mellitus. There is currently no treatment that reverses the atrophic changes associated with this lesion. We have carried out a clinicopathologic study on 15 subjects and, in addition, have reviewed 10 further biopsy specimens of necrobiosis lipoidica diabeticorum. We found a frequent association of necrobiosis lipoidica diabeticorum with other chronic complications of diabetes mellitus, including limited joint mobility. It is possible that nonenzymatic glucosylation or other changes in collagen may be important in the etiology of necrobiosis lipoidica diabeticorum and the limited joint mobility. We confirmed that cutaneous anesthesia is usually present in the necrobiosis lipoidica diabeticorum lesions. With the use of an antibody to S100 protein and an immunohistochemical method, there was an apparent decreased number of nerves in the skin lesions. We suggest that sensory loss results from local destruction of cutaneous nerves by the inflammatory process. Finally, in six elliptical biopsies extending into clinically normal skin, we demonstrated that the inflammatory infiltrate of necrobiosis lipoidica diabeticorum extended from the lesion into apparently normal skin surrounding clinically active lesions. Thus, intradermal steroids might be administered to perilesional areas surrounding active lesions in the hope of halting progression.  相似文献   
45.
ObjectiveTo investigate the calcium and phosphorus contents of four domestic animals used as sources of meat in Nigeria.MethodsThe calcium contents of the body parts of the animals were determined using atomic absorption spectrometer. Their phosphorus contents were determined colorimetrically using the molybdenum blue method.ResultsThe calcium and phosphorus contents were significantly higher in the bone samples than in the other animal parts investigated (P<0.05). The calcium contents of all the edible parts were higher in chicken than in the other animals. High calcium and phosphorus contents were detected in the faeces of chicken and goat, and that of cattle and goat, respectively. Low calcium and phosphorus contents were detected in the urine samples. Calcium: phosphorus ratios calculated for the bones of chicken, cattle and goat were satisfactory.ConclusionsIn conclusion, calcium and phosphorus contents of the animal parts vary significantly and their relative contents may be related to the animal's diet. Chicken parts may be the preferred dietary source of these minerals. This study highlights the need for routine investigation of the mineral contents of food, which is necessary for proper nutritional guidelines.  相似文献   
46.
The practice of allowing family to be present during patient resuscitation or invasive procedures (Family Presence) is gaining acceptance in North America and the United Kingdom in controlled circumstances. Research into Family Presence has demonstrated multiple benefits for the patient, family and health care team. These advantages include helping the family to understand the severity of the illness/trauma and to see that appropriate attempts were undertaken to save their loved one. Family Presence can also facilitate improved communication between the health care team and family. In spite of evidence supporting Family Presence as a useful practice for patient, family and health care team, the use of Family Presence is uncommon within Australian emergency departments and hospitals. Clear expectations at organisational, governmental and professional levels are essential to effectively implement this approach. To be supported in the clinical area, the success of a Family Presence program requires an inclusive approach to program development. A critical component of a successful Family Presence program is a family facilitator who is adequately prepared for the role and committed to supporting the family during resuscitation or invasive procedures. Research exploring Family Presence in Australia is lacking and highlights the need for context specific research in this area.  相似文献   
47.
These are case reports of two children with structurally normal hearts and with normal coronary arteries, who survived myocardial infarction in the early neonatal period. They are only the third and fourth reported survivors of neonatal myocardial infarction and the first in which hypercholesterolemia is postulated to have played an important role. The most likely cause of the myocardial infarction was thrombosis or thromboembolism. Changes in hemostatic function associated with hypercholesterolemia may be relevant.  相似文献   
48.
OBJECTIVE: To test the hypothesis that adjunctive intracameral 1% lidocaine reduces intraoperative pain during phacoemulsification using topical anesthesia. DESIGN: Prospective, double-masked, randomized, controlled trial. PARTICIPANTS: A total of 200 patients undergoing routine phacoemulsification under topical 1% tetracaine were studied. INTERVENTION: Randomization to 0.5 ml intracameral, unpreserved, epinephrine-free 1% lidocaine or placebo was conducted. MAIN OUTCOME MEASURE: Intraoperative pain was quantified by the patients using a 0-10 visual analog pain scale. RESULTS: Intraoperative pain scores (+/- standard deviation) for the lidocaine and control groups were 1.29 +/-1.24 and 1.44 +/- 1.33, respectively (P > 0.35). CONCLUSIONS: In a rigorously double-masked, prospective, randomized, controlled trial there was no significant reduction in intraoperative pain when intracameral 1% lidocaine was used during phacoemulsification under topical anesthesia.  相似文献   
49.
PURPOSE: To develop and evaluate a new method to quantify centration of the trephined donor cornea relative to the limbus. METHODS: After human donor corneas were trephined for penetrating keratoplasty, the remaining corneoscleral discs were stained and subjected to image analysis. The centration of the excised donor cornea relative to the limbus was calculated by measuring their centroids from the "captured" images. RESULTS: Fifty-two corneoscleral discs were analyzed. The average deviation from the centre was 0.32 mm (SD, 0.18 mm). Neither surgeon nor the type of trephine significantly influenced the mean centroid deviation. CONCLUSION: We have developed and evaluated a method to quantify centration of human donor cornea. In a small series, decentration did not correlate significantly with either the surgeon or the trephine.  相似文献   
50.
Boulton E  Cleary H  Plumb M 《Carcinogenesis》2002,23(6):1079-1085
Thymic lymphoma is a very common spontaneous and/or induced malignancy in both inbred mice and in transgenic mouse models of human cancer. Although a thymic lymphoma is defined as thymus-dependent T-cell malignancy, diagnostic criteria vary between studies and considerable heterogeneity has been reported. To define and classify the thymic lymphomas that arose in our study of X-irradiated (CBA/HxC57BL/6)F1, F1 backcross and F1 intercross mice, 66 thymic lymphomas were immunogenotyped for immunoglobulin heavy chain (IgH) and T-cell receptor beta (TCRbeta) gene rearrangements, and/or analysed for expression of lineage-specific markers and allelic loss on chromosome 4. The data indicate that 33% of the thymic lymphomas are very similar to mouse radiation-induced acute myeloid (AML) and mixed lineage (IgH(R), TCRbeta(G)) pre-B lympho-myeloid (L-MLs) leukaemias, 33% are mixed lineage (IgH(R), TCRbeta(R)) B/T lymphoid and <33% can be described as single lineage (IgH(G), TCRbeta(R)) T-cell malignancies. As the myeloid and L-ML leukaemias are not thymus-dependent this suggests that a malignant myeloid or pre-B lympho-myeloid cell can colonize the spleen to give an AML or L-ML leukaemia, or can colonize the thymus where TCRbeta gene rearrangement(s) may be induced to give the mixed lineage thymic lymphomas. Thus, assuming the single lineage T-cell thymic lymphomas fulfil the criteria of a thymus-dependent T-cell malignancy, thymic lymphomas are comprised of at least three distinct malignancies.  相似文献   
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