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81.
Concordance of creatine kinase-MB activity and mass   总被引:1,自引:0,他引:1  
The recent availability of monoclonal antibodies that are highly specific for creatine kinase (CK; EC 2.7.3.2) MB isoenzyme should allow for the development of rapid, sensitive, and specific assays of CK-MB mass and activity. However, the relationship between the mass concentration of CK-MB and its activity in plasma has previously been thought by some to be variable. To determine the extent to which discrepancies of potential clinical significance might arise between measurements of activity and mass in plasma, we compared CK-MB activity and concentration in 1298 samples obtained from 226 patients admitted to the cardiac-care unit. CK-MB activity concentration was determined with an immunoadsorption assay, and mass concentration was measured by an automated "sandwich" assay (Magic Lite; Ciba Corning Diagnostics). Both of these assays are based on specific monoclonal antibodies for CK-MB. Values obtained with these assays correlated well (r = 0.94). Normal and abnormal values with the two assays were concordant in 96% of the samples. In all but three instances, differences occurred late after myocardial infarction and were characterized by minimal increases as determined by one method vs values at the upper limit of normal as determined with the other. Thus, measurements of CK-MB mass and activity concentrations in plasma with assays based on these specific monoclonal antibodies are comparable for the detection or exclusion of acute myocardial infarction.  相似文献   
82.
Although there is relatively little information concerning the oral health of handicapped adults there is increasing evidence to suggest that their oral condition, particularly periodontal health, is poor. The present investigation involved assessment of 382 handicapped patients attending four different Adult Training Centres in Birmingham. The caries status, oral hygiene, and periodontal conditions were evaluated and the Community Periodontal Index of Treatment Need (CPITN) was calculated. In order to assess the manual dexterity and the comprehension of the trainees a standard test was devised. This consisted of timing each participant in carrying out simple instructions to pick up and position certain common objects. The results indicated high levels of plaque, calculus, and bleeding with a mean CPITN of 7.43. The mean time taken for the manual dexterity and comprehension test was 23.9 seconds with a range from 10 to 80 seconds, S.E.+/- 1.33. This compares with results from 34 "normal" adults of a mean time of 8.2 seconds +/- 1.8 with a range of 6 to 12 seconds. There was no significant correlation between the Manual Dexterity and Comprehension scores and the periodontal indices in the handicapped adults.  相似文献   
83.
The fresh brain weights of 79 infants with sudden infant death syndrome (SIDS) were tabulated and compared with expected "normal" brain weights. The series included 47 males and 32 females. Their ages ranged from 8 days to 16 months with a median of 2.5 months. The weights of all these brains were above the 50th percentile for age, and 64 of 79 brains (81%) were above the 95th percentile, including 15 (19%) at or above the 99.9th percentile. The ratio of the brain stem plus cerebellum weight to the whole brain weight of 93 formalin-fixed brains from victims of SIDS showed that the cerebrum was disproportionately heavier in most cases. No gross or microscopic evidence of cerebral edema was noted to account for the heavier weight. The significance of these findings is debatable. The increase in brain weight was less obvious in infants younger than 1 month of age but accelerated after that age. The brain weights of infants with SIDS may represent the really "normal" weights, since these patients were not known to be ill prior to death. If the brain weights of SIDS infants are really heavier than "normal," the possibility must be considered that disproportionately rapid growth of the brain during early infancy may be detrimental to the neural control of the cardiorespiratory system.  相似文献   
84.
Transrectal needle aspiration biopsy and core biopsy of the prostate were performed simultaneously on 88 men with prostatic nodules. Cytologic and histologic assessments were made in a blinded, independent fashion, and the results were compared. All patients with positive findings on aspiration also had positive findings on core biopsy, for a positive predictive value for aspiration of 100%. However, five negative and six "insufficient" results obtained by aspiration were positive on core biopsy, for a negative predictive value for aspiration of 88%. This experience support the use of needle aspiration as an initial diagnostic maneuver in the assessment of prostatic nodules.  相似文献   
85.
Two reliable techniques for the microvascular anastomosis of difficult-to-handle, thin-walled smaller vessels--"insert sutures first, tie later" and "loops on hanger"--are described.  相似文献   
86.
The records of 167 patients with grade 1 or 2 supratentorial pilocytic astrocytomas (41 patients), ordinary astrocytomas (91 patients), or mixed oligoastrocytomas (35 patients) diagnosed between 1960 and 1982 are retrospectively reviewed. The extent of surgical tumor removal was gross total or radical subtotal in 33 patients (20%) and subtotal or biopsy only in the remaining 134 patients (80%). Postoperative radiation therapy was given to 139 (83%) of the 167 patients, with a median dose of 5000 cGy (range 600 to 6500 cGy). Multivariate analysis revealed that a pilocytic histology was the most significant prognostic variable associated with a good survival. The 5- and 10-year survival rates were, respectively, 85% and 79% for the 41 patients with pilocytic astrocytomas compared to 51% and 23% for the 126 patients with ordinary astrocytomas or mixed oligoastrocytomas. Postoperative irradiation did not appear to be associated with improved survival times in the patients with pilocytic astrocytomas; however, in the 126 patients with ordinary astrocytomas or mixed oligoastrocytomas, those who received "high-dose" radiation (greater than or equal to 5300 cGy) had significantly better survival times than those who received "low-dose" radiation (less than 5300 cGy) or surgery alone. The 5- and 10-year survival rates were, respectively, 68% and 39% for the 35 patients receiving high-dose radiation, 47% and 21% for the 67 receiving low-dose radiation, and 32% and 11% for the 19 treated with surgery alone. The survival rate was poor for the 23 patients with ordinary astrocytomas and oligoastrocytomas who underwent gross total or radical subtotal tumor removal (14 of whom were also irradiated): 52% at 5 years and 21% at 10 years, with 19 of 23 patients developing tumor progression and dying 1 to 12 years postoperatively. In contrast, all 10 patients with pilocytic astrocytomas who had gross total or radical subtotal tumor removal alone were long-term survivors, with follow-up periods of about 4 to 25 years.  相似文献   
87.
Summary A correlative light and electron microscopic investigation was undertaken to determine the morphology and distribution of catecholamine (CA)-containing axon terminals in the hypoglossal nucleus (XII) of the rat. This was accomplished immunocytochemically with antibody to tyrosine hydroxylase (TH). The major findings in this study were the following: 1) Immunoreactive profiles were found throughout XII and included unmyelinated axons, varicosities, axon terminals and dendrites; 2) Nonsynaptic immunoreactive profiles (preterminal axons, varicosities) were more frequently observed (55.2%) than synaptic profiles (43.5%); 3) CA-containing axon terminals ending on dendrites were more numerous (71.8%) than those synapsing on somata (25.4%) or nonlabeled axon terminals (2.7%); 4) The morphology of labeled axon terminals was variable. Axodendritic terminals typically contained numerous small, round agranular vesicles, a few large dense-core vesicles and were associated with either a symmetric or no synaptic specialization, axosomatic terminals were often associated with a presynaptic membrane thickening or a symmetric synaptic specialization and contained small, round and a few elliptical-shaped vesicles, while axoaxonic synapses formed asymmetric postsynaptic specializations; and 5) CA-positive dendritic processes were identified in XII. These findings confirm the CA innervation of XII, and suggest a complex, multifunctional role for CA in controlling oro-lingual motor behavior.  相似文献   
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Erythrocyte transketolase activation by thiamin diphosphate has been studied in elderly patients with moderate or severe chronic dementia, acute alcoholic admissions and chronic alcoholics with evidence of brain damage, mostly of the Wernicke-Korsakoff type. Significantly more patients in each group than controls showed abnormal activation of transketolase, not only by 0.3 mM thiamin diphosphate (TDP) but also in further activation by increase to 3 mM. This indicated the presence in a proportion of the alcoholic and the demented patients of an abnormal enzyme variant, similar to that previously found in vitro. The modified transketolase activation test may warn not only of marginal thiamin deficiency but also independently, of susceptibility to brain damage in patients at risk.  相似文献   
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