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91.
92.
Native American, Hispanic, and Anglo sixth graders reacting to an example of teenage problem drinking expressed similar beliefs and attitudes in many respects. However, Native American children viewed the problem as less serious, subscribed more to a disease theory of alcoholism, attributed less causal responsibility to the individual, and adopted a less aggressive approach toward treatment than did Hispanic, and especially Anglo, children. Their less conventional value orientations accounted for all these differences except their stronger endorsement of a disease theory of problem drinking.  相似文献   
93.
94.
Hodgkin disease: CT of the thymus   总被引:2,自引:0,他引:2  
Heron  CW; Husband  JE; Williams  MP 《Radiology》1988,167(3):647-651
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.  相似文献   
95.
BACKGROUND AND PURPOSE: Although indomethacin has been demonstrated to prevent germinal matrix and intraventricular hemorrhage in clinical and animal studies, the mechanism of action of this agent to prevent hemorrhage remains unclear. Previous studies have demonstrated both that the microvessels in the germinal matrix of newborn beagle pups undergo basement membrane maturation during the first 4 postnatal days and that indomethacin may promote laminin deposition in tumor cell culture systems. METHODS: We employed the newborn beagle pup model to test the hypothesis that indomethacin may stimulate laminin deposition in germinal matrix microvessels. Newborn pups were randomized to receive either 0.1 mg/kg/dose i.p. indomethacin or an equal volume of saline diluent. Pups received doses of study medication once a day for 1, 2, or 3 days and were studied on postnatal days 1, 2, 3, or 4. Pups were anesthetized and systemically perfused with buffered formalin; the brains were removed and prepared for immunohistochemical study. RESULTS: Sections stained with Bandeiraea lectin demonstrated that there was no difference in germinal matrix vessel density among the postnatal ages studied; similarly, there were no differences in vessel density between saline- and indomethacin-treated animals at any postnatal age. Quantification of germinal matrix stained intensity by confocal microscopy demonstrated significant increases in indomethacin-treated pups for both laminin staining at postnatal days 2 (p = 0.05) and 3 (p = 0.0009) and type V collagen staining at postnatal day 2 (p = 0.011). Although staining for beta 1 integrins increased across postnatal ages, there were no differences between saline- and indomethacin-treated animals. CONCLUSIONS: These data suggest that indomethacin may stimulate basement membrane deposition in the germinal matrix microvessels of newborn beagle pups to prevent germinal matrix and/or intraventricular hemorrhage.  相似文献   
96.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
97.
We studied the effect of postoperative administration of subconjunctival 5-fluorouracil in maintaining postoperative filtration following combined trabeculectomy and extracapsular cataract extraction with posterior chamber lens implantation. Three months postoperatively, the mean intraocular pressure in 15 patients who had received 5-fluorouracil was 13.1 +/- 3.2 mm Hg; in 17 control patients, it was 13.0 +/- 3.0 mm Hg (P greater than .05). The mean number of postoperative medicines in the study patients was 0.7; in the control patients, 0.8 (P greater than .05). Bleb appearance and improvement in visual acuity were similar in the two groups. This study does not support the routine use of 5-fluorouracil in patients who have undergone combined trabeculectomy and extracapsular cataract extraction.  相似文献   
98.
The internal mammary artery is currently the arterial replacement of choice for coronary artery bypass grafts. The authors studied the permeability of the vessel wall of the internal mammary artery and the ascending aorta in 12 patients undergoing coronary artery bypass grafts by comparing the 125I-albumin binding profiles. Their results suggest that albumin crosses the internal mammary artery more easily than in the aorta.  相似文献   
99.
A modified end-point enzymatic method for the measurement of ammonia in stool water is presented. A protein precipitation step was included in order to inactivate urease and faecal enzymes, which oxidise NADH. The modified method is reliable, with acceptable precision and accuracy, and is linear up to a concentration of 1.5 mmol/l.  相似文献   
100.
The duration of retention of tolerance to ethanol was tested in the alcohol-preferring (P) and alcohol-nonpreferring (NP) rats lines, using ethanol-induced hypothermia as a measure of tolerance. Rats received two injections of ethanol (3.5 g/kg) body wt, IP) and the time between the injections was 1, 2, or 3 days. When one day separated the two injections, tolerance to the hypothermic effect of a second “test” injection was found in both lines. When 2 or 3 days separated the two injections, the P line showed a loss of tolerance and the NP line showed sensitization to ethanol. Sensitization in the NP line grew stronger when the interval between injections was increased from 2 to 3 days. The duration of retention of tolerance to ethanol-induced hypothermia in the P line was shorter than has previously been reported for motor impairment in this line. It appears that the duration of tolerance retention in the P line depends on the test used to measure tolerance. Sensitization to ethanol in the NP line may be associated with low oral ethanol intake. This research was supported, in part, by grants AA08312, AA03243, and AA07611 from the PHS  相似文献   
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