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991.
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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   
995.
Summary Retrograde and anterograde tracing methods were used to study the connections between the parahippocampal gyrus and the posterior auditory association cortex (area Tpt) in the Old-World monkey. Nine monkeys received injections of tritiated amino acids in different areas of the parahippocampal gyrus, and three monkeys received injections of the retrograde tracer fast blue in area Tpt of the auditory association cortex. It was observed that the medial part of the posterior portion of the parahippocampal gyrus (areaTH) gives rise to projections that terminate in layers I–III of area Tpt. Using complementary retrograde tracing experiments, the cells of origin for this projection were identified in layers V and VI of area TH. The findings reveal a direct structural coupling between auditory association cortices and a temporal region thought to play a role in learning and memory. These connections may form part of a neural system in the monkey that is related to acoustic learning and memory. Homologous systems in humans may be involved in auditory learning and language acquisition.  相似文献   
996.
997.
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   
998.
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   
999.
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   
1000.
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   
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