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951.
952.
A system for minimally restraining adult baboons with chronic intravenous (IV) or intragastric (IG) catheters for long term pharmacological and behavioral studies is described. The system consists of an adjustable foampadded backplate and harness which is custom-fitted to each animal. A flexible stainless-steel cable connects the backplate to a liquid swivel through which the drugs are administered. Methods for the preparation and surgical implantation of IV and IG catheters are also described. Intravenous catheters were sequentially implanted in the internal jugular, femoral, axillary and external jugular veins. Catheters have remained patent for as long as 45 months, and catheter life appears to be conjointly determined by both site and number of successive implantations. The advantages of the harness/tether system over previously used chair-restraint procedures include greater freedom of movement, fewer restraint-related health problems, and longer experimental life of the animals.  相似文献   
953.
954.
The arthropathy of calcium pyrophosphate dihydrate (CPPD) crystal deposition disease is distinctive and may affect lumbar spinal and sacroiliac joints, as well as appendicular joints. Subchondral pseudocysts that are a hallmark of the disease have a variable appearance, but often occur as a typical cluster of subchondral, coalescent lucencies with smudged, sclerotic margins. Structural joint collapse with fragmentation of cartilage and bone may occur and appear to be related, at least in some cases, to antecedent pseudocysts. Characteristic intra-articular osteochondral bodies are often extensive and may affect multiple joints; their pathogenesis is discussed. Articular synovial calcification is common and may be due to calcium hydroxyapatite, as well as CPPD, particularly if advanced degenerative changes are present. Recognition of the radiologic features may be encountered in CPPD crystal deposition disease is important for differential diagnosis.  相似文献   
955.
One hundred forty-eight patients with advanced carcinoma of the urinary bladder Stages C or D1 were randomized between continuous-course radiotherapy (6,000 cGy in 30 fractions of 200 cGy each, over 6 weeks) and split-course radiotherapy (2,750 cGy in 10 fractions of 275 cGy each, over 2 weeks; a rest period of 3 weeks; 2,750 cGy in 2 weeks); 139 are analyzed in this report. Ninety-four percent of the patients have been followed at least 5 years or until death. The patients ranged in age from 45 to 80 with a median of 69. Seventy-six percent of the patients were males and 58% had Stage C disease. In patients with information on the size of the tumor, in 66% the lesion measured 5 cm or larger; 26% had a diameter of 8 cm or larger. In general, the treatment groups were well balanced with respect to patient characteristics. Both treatment groups tolerated therapy well. Eighty-seven percent of the patients completed therapy, 66% as planned. Fifty-four percent experienced at least one severe reaction, with the most common types being diarrhea (28%), frequency of urination (24%), soreness or burning on urination (25%), and urgency of urination (19%). Late effects of therapy were minimal. Median survival times were 11.5 months and 9.4 months for continuous-course and split-course, respectively. The treatment differences were not significant (p = 0.88; Mantel-Haenszel stratified by stage and sex). Forty percent of the patients became free of all clinically detectable disease following radiotherapy either alone or in combination with additional surgery (40% for continuous-course, 4% cleared by surgery, and 39% for split-course, 3% cleared by surgery). When the tumor measured less than 5 cm, the clearance rate was 61% (20/33) vs. 33% (13/39) for 5-7.9 cm, and 24% (6/25) for 8 cm or larger (p less than 0.01; chi2 test for linear trend). For those who became disease free, median time disease free within the irradiated volume was 72 months for continuous-course and is currently undefined for split-course; median time disease free was 28 months and undefined, respectively. There were no significant treatment differences in tumor control for any of these endpoints. The ultimate long-term tumor control in the pelvis was 28% (19/68) for continuous- and 25% (18/71) for split-course therapy.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
956.
We treated 14 patients with hairy cell leukemia, 13 of whom had progressive disease, with recombinant alpha-2 interferon administered sc at 2 X 10(6) units/m2, three times per week. Thirteen patients were evaluable for response. All evaluable patients responded within 6-8 weeks. After a minimal treatment duration of 6 months and a maximal of 12 months, three patients have achieved complete response and ten have achieved partial response. With a median treatment duration of 10 months, the responding patients' hematologic parameters are continuing to improve, and no responding patients have relapsed. This outpatient self-administered regimen is well-tolerated, with mild fever, myalgias, and headache usually resolving within 2 months. Although the optimal regimen and the mechanism of action are unknown, recombinant alpha-2 interferon may be the treatment of choice for patients whose disease progresses after splenectomy or who are not surgical candidates.  相似文献   
957.
The ECG has limitations in the evaluation of the chest-pain patient, including the presence of confounding ECG patterns; the ECG patterns that confound the diagnosis of acute myocardial infarction(AMI) include left bundle branch block (LBBB), ventricular paced rhythms (VPR), and left ventricular hypertrophy (LVH). These patterns produce new ST-segment/T-wave abnormalities, which are the new normal findings in these patients and may lead the clinician astray in two distinct instances: (1) diagnosing ECG change related to acute coronary syndromes (ACS) when the abnormality results solely from the confounding pattern; and (2) not acknowledging the confounding nature of these ECG patterns in the evaluation of potential ACS, thereby placing excessive diagnostic confidence in the ECG. This article highlights the diagnostic dilemma encountered in these confounding ECG patterns; the discussion focuses on the expected ECG abnormalities in these patients and the findings seen in ACS.  相似文献   
958.
OBJECTIVE: The aim of the study was to determine if pain and distress during the retinopathy of prematurity (ROP) screening examination could be ameliorated by providing comfort care. STUDY DESIGN: This study was a prospective, randomized, controlled trial of 30 stable preterm infants who underwent initial ROP screening examinations. Fourteen study infants were swaddled, held, and given 24% sucrose solution during the examination. Sixteen controls were examined while lying in their cribs. Vital signs (i.e., pulse rate, respiratory rate, and oxygen saturation), crying time, and time for the vital signs to return to baseline values were recorded at different times during the examination. RESULTS: The vital signs did not vary significantly between the two groups. The participants in the control group had a trend of longer crying time, but this trend did not reach a level of statistical significance. In addition, The time required for the vital signs to return to their baseline values did not vary significantly. CONCLUSION: ROP screening is very distressful for preterm infants. The routine use of comfort care to reduce pain during the examination could not be supported by this study.  相似文献   
959.
PURPOSE: To evaluate prospectively the incidence and severity of centripetal lens epithelial cell migration (CLECM) onto the anterior surface of the Alcon SA60AT intraocular lens (IOL). METHODS: One hundred and four consecutive cases of SA60AT IOL implantations were prospectively evaluated. At the 1-month postoperative visit, best corrected visual acuity (BCVA) was obtained. Following maximal pupillary dilatation, the extent of CLECM was assessed using a simplified grading scale (0-4). The centrality of the lens within the capsular bag was recorded. Patients with the highest grade of CLECM were recalled for reassessment at a minimum of 3 months. RESULTS: Centripetal lens epithelial cell migration data were obtained on 99 patients. Of these, 94% demonstrated CLECM of varying severity at 1 month postoperatively. The severity was low grade in 54% of patients (29% grade 1, 24% grade 2), and high grade in 40% of patients (16% grade 3, 24% grade 4). BCVA results were good (91.9% 6/6 or better) and did not correlate with CLECM grade. Operative capsulorhexis size did not correlate with the severity of CLECM. The lens was well-centred in 91 of 92 patients in whom lens position was assessed. Twenty-three patients with grade 4 CLECM at 1 month were brought back for reassessment (3.5-13 months postoperatively) and 18 of these demonstrated complete regression of CLECM (to grade 0). CONCLUSIONS: There is a high incidence and severity of CLECM 1 month postoperatively using the Alcon SA60AT IOL. There was no significant correlation between CLECM grade and either BCVA at 1 month, capsulorhexis size or lens centration. CLECM appears to be a frequent, benign and transient event with this lens.  相似文献   
960.
On 21 May 1981 the WHO International Code of Marketing Breast Milk Substitutes (hereafter referred to as the Code) was passed by 118 votes to 1, the US casting the sole negative vote. The Code arose out of concern that the dramatic increase in mortality, malnutrition and diarrhoea in very young infants in the developing world was associated with aggressive marketing of formula. The Code prohibited any advertising of baby formula, bottles or teats and gifts to mothers or 'bribery' of health workers. Despite successes, it has been weakened over the years by the seemingly inexhaustible resources of the global pharmaceutical industry. This article reviews the long and tortuous history of the Code through the Convention on the Rights of the Child, the HIV pandemic and the rare instances when substitute feeding is clearly essential. Currently, suboptimal breastfeeding is associated with over a million deaths each year and 10% of the global disease burden in children. All health workers need to recognise inappropriate advertising of formula, to report violations of the Code and to support efforts to promote breastfeeding: the most effective way of preventing child mortality throughout the world.  相似文献   
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