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91.
Changes in desmosomes were noted in nonacantholytic regions of skin explants cultured in the presence of intercellular antibodies. These changes included dissociation of desmosomes, as well as a "selective loss" of desmosomal components in one or both of neighboring cells.  相似文献   
92.
Computed tomography in the diagnosis of cavernous hemangioma of the liver   总被引:2,自引:0,他引:2  
Computed tomography (CT), using a sequential timed scanning technique, was performed on six patients with hepatic cavernous hemangiomas. Initial examination shows a moderately homogeneous circumscribed area with reduced attenuation values. Serial scans after injection of a bolus of contrast material show early peripheral opacification while the central part of the lesion retains low attenuation values for several minutes. Later scans demonstrate a variable degree of "filling in" of the central part of the hemangioma. If the characteristic appearance of this lesion is recognized, confusion with other ominous lesions and biopsy can be avoided. Because of limited experience, the described pattern may not be absolutely pathognomonic for hemangioma, so angiography is currently advised to confirm the diagnosis.  相似文献   
93.
The mammalianCAD gene codes for a 240-kDa multifunctional protein that catalyzes the first three steps of de novo pyrimidine biosynthesis. Previously, the longest cDNA construct available was missing approximately 500 bp of coding sequence at the 5 end, thereby lacking the sequence to encode the entire carbamylphosphate synthetase (CPSase) domain. Here, a completeCAD hamster cDNA is constructed, placed into a mammalian expression vector, and transfected into hamster cells deficient in CAD. Transfectants show coordinately restored levels of all three enzyme activities and the presence of full-length CAD protein. A derivative construct of theCAD cDNA was generated that should encode only the CPSase domain. When transfected into mammalian cells, a protein was synthesized that had significant CPSase activity both in vivo and in vitro. The two constructs generated in this study will facilitate the study of CAD structure, function, and allosteric regulation.  相似文献   
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Six subjects each smoked a 1% marijuana cigarette and 2 hr later smoked a second one. Plasma levels of delta-9-tetrahydrocannabinol were measured for 9 hr with a radioimmunoassay. Heart rate and self-reported "high" were measured for 2 hr after each cigarette. All three measures showed a rapid increase after the start of smoking with Cmax occurring before the end of smoking. There was a strong correlation between decrease in heart rate and plasma levels from 10 min after smoking until 120 min. All pharmacodynamic response measures returned to baseline values within approximately 2 hr.  相似文献   
97.
98.
The systemic involvement in scleroderma   总被引:1,自引:0,他引:1  
A survey was made of the systemic involvement in 38 patients with scleroderma: 33 with the acrosclerotic form (Type 1, 18, Type 2, 15) and five with the diffuse form. The study comprised inquiry about symptoms, physical examination, and the laboratory tests, such as radiological examination of chest and hands, barium swallow and meal X-ray examination, electrocardiography, pulmonary function tests, haematology tests, examination for autoantibodies, and a battery of biochemical tests. Evidence of some systemic involvement (that is, in addition to skin) was almost universal. Similar disturbances occurred both in the acrosclerotic and in diffuse forms. The most common clinical involvement was that of the joints and gastrointestinal tract. The most common confirmatory signs were a positive "neck test" (tethering of the skin of the root of the neck and upper part of the chest on extending the head) and telangiectasia. The most common abnormalities in test results were those found in X-ray films of the hands (about 80%), and in pulmonary function, and barium swallow and meal X-ray studies (each about 70%). The most frequent abnormalities in the biochemical scan were increased levels of immunoglobulin M (IgM), and decreased creatine clearance.  相似文献   
99.
OBJECTIVE: This study determined the extent to which adding structured procedures improved diagnostic accuracy for outpatients with severe mental illness in a community mental health setting. METHOD: The Structured Clinical Interview for DSM-III-R (SCID) was used to interview 200 psychiatric outpatients. A research nurse reviewed medical records and amended the SCID diagnoses accordingly. A research psychiatrist or psychologist reviewed the diagnostic data and interviewed each patient to verify or further modify the previous findings. Diagnostic outcomes at each step of the procedure were compared to determine whether adding additional data improved diagnostic accuracy. The additional time required for each element of the diagnostic procedure was also assessed. RESULTS: Kappa comparisons of the different diagnostic levels showed that adding additional data significantly improved accuracy. Diagnoses rendered by combining the SCID and review of the medical record were the most accurate, followed by the SCID alone, and then diagnoses made by psychiatrists during routine care. In addition, the SCID alone identified five times as many current and past secondary diagnoses as were documented routinely in patients' charts. CONCLUSIONS: Combining structured interviewing with a review of the medical record appears to produce more accurate primary diagnoses and to identify more secondary diagnoses than routine clinical methods. The patients' knowledge of their diagnoses was limited, suggesting a need for patient education in this setting. Whether use of structured interviewing in routine practice improves patient outcomes deserves further study.  相似文献   
100.
Anti-GQ1b antibodies are typically found in patients with the Miller Fisher syndrome, all of whom will have, by definition, acute ophthalmoplegia. The authors describe three patients with chronic ophthalmoplegia in the presence of persistently high titers of immunoglobulin G anti-GQ1b antibody detected in an ELISA, one of whom improved with immunotherapy. Anti-GQ1b antibodies may be associated with some cases of chronic ophthalmoplegia of unknown cause.  相似文献   
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