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991.
In 570 patients with sporadic primary hyperparathyroidism, the age, sex, symptoms, and preoperative serum calcium values were related to the histopathologic diagnoses, operative findings, and the extent and outcome of parathyroid surgery. Renal stone formation was especially prevalent in younger patients with slight hypercalcemia and parathyroid chief cell hyperplasia, whereas neuromuscular and psychiatric disturbances were overrepresented among older women with higher serum calcium values. Serum calcium concentration was inversely correlated to the proportional incidence of chief cell hyperplasia and positively correlated to the glandular weight of both adenomas and hyperplasias. Glandular size was markedly irregular in chief cell hyperplasia, with increased gland weights of no more than two glands in 78% of patients. During follow-up, for as long as 27 years, normocalcemia was obtained in 91% of patients with adenomas, with failures mainly depending on difficulties in identifying the parathyroid glands. The rate of normocalcemia was lower (80%) among patients with hyperplasia, but an inability to visualize the glands was not a major cause of failure. In patients with hyperplasia with asymmetric and more markedly enlarged glands, it appeared sufficient to remove only the enlarged glands, whereas the findings advocated a subtotal 3- to 3.5-gland resection in patients with more symmetrically or less enlarged hyperplastic glands.  相似文献   
992.
'Grown-up' congenital cardiac patients are an increasing medical community, not at present being properly cared for in any country. Information on over 2000 patients aged 15-65 years with congenital heart disease who have been treated in the National Heart Hospital provides the data for this report.  相似文献   
993.
1. Effects of a novel imidazoindole derivative on cholinergic function were studied in isolated tissue preparations. 2. The compound demonstrated a dose-dependent (10(-11)-10(-9) potentiation (20-60%) of acetylcholine induced tension in guinea pig ileal tissue. 3. Increases in the size of end-plate potentials and nerve evoked muscle twitches were observed in frog nerve-skeletal muscle preparations. 4. Cholinesterase activity was not inhibited. 5. The results suggest that the compound has actions at the post-synaptic muscarinic receptor complex in smooth muscle and causes pre-synaptic increases in ACh release at the neuromuscular junction.  相似文献   
994.
995.
Mortality prognostic factors in chest injury   总被引:2,自引:0,他引:2  
1,026 multiple trauma patients (P) were compared to P with chest injuries (PCT) (407). Severity indices were related to type of thoracic injury and mortality. The Injury Severity Score (ISS), Glasgow Coma Scale (GCS), Trauma Score (TS), CHOP, and the Respiratory Index (RI) were used. The mortality rate of P was 27.1% but increased to 32.9% for PCT (p less than 0.05). We noted that mortality rate was highly dependent on major chest trauma: 68.6% for flail chest (FC), 56% for lung contusion (LC), 42.3% for hemothorax (HA), and 38.1% for pneumothorax (PN). ISS and RI scores for PCT survivors were greater than ISS + RI scores for P survivors (p less than 0.05 and p less than 0.01). ISS values for LC, HA, and PN PCT survivors were greater than the ISS of P survivors (p less than 0.01). Nonsurviving PCTs, especially those with lung contusion, showed a highly significant increase in ISS and RI scores.  相似文献   
996.
997.
BACKGROUND: The aim was to determine the influence of the socioeconomic status of the family and the hygienic practices in the home on the prevalence of head lice infestation in children. METHODS: The study was carried out by analyzing the answers to a standardized epidemiological questionnaire given to parents of school children aged 4-17 in Bet Shemesh, a medium-sized urban town 25 km from Jerusalem. RESULTS: Of 3,000 questionnaires distributed, 958 (31.9%) were completed and returned. The majority of the children (72.4%) had been previously infested with lice. Half of them had other family members, mainly brothers and sisters, who had been infested in the past with lice. In 97.5% of the families the mother was responsible for examining the children for lice, and for carrying out treatment when infestation was present. An association was found between presence of lice infestation and mother's education, age of child, and frequency of shampooing, combing, and examination for lice. There was no association between infestation rates and mother's country of origin, crowding in the home, and the sharing of combs, brushes, hats, scarves, towels, and clothes. CONCLUSIONS: There is evidence that the incidence of lice infestation depends on the hygienic practices in the home rather than on the socioeconomic status of the family or sharing of personal articles among family members.  相似文献   
998.
Assessment of glomerular filtration rate (GFR) with inulin is cumbersome and time-consuming. Radioisotopic filtration markers have been studied as filtration markers because they can be used without continuous intravenous (IV) infusion and because analysis is relatively simple. Although the clearances of 99mTc-diethylenetriamine-pentaacetic acid (DTPA), 169Yb-DTPA, and 125I-iothalamate have each been compared with inulin, rarely has the comparability of radioisotopic filtration markers been directly evaluated in the same subject. To this purpose, we determined the renal clearance of inulin administered by continuous infusion and the above radioisotopic filtration markers administered as bolus injections, simultaneously in four subjects with normal renal function and 16 subjects with renal insufficiency. Subjects were studied twice in order to assess within-study and between-study variability. Unlabeled iothalamate was infused during the second half of each study to assess its effect on clearances. We found that renal clearance of 125I-iothalamate and 169Yb-DTPA significantly exceeded clearance of inulin in patients with renal insufficiency, but only by several mL.min-1.1.73m-2. Overestimation of inulin clearance by radioisotopic filtration markers was found in all normal subjects. No differences between markers were found in the coefficient of variation of clearances either between periods on a given study day (within-day variability) or between the two study days (between-day variability). The true test variability between days did not correlate with within-test variability. We conclude that the renal clearance of 99mTc-DTPA, 169Yb-DTPA, or 125I-iothalamate administered as a single IV or subcutaneous injection can be used to accurately measure GFR in subjects with renal insufficiency; use of the single injection technique may overestimate GFR in normal subjects.  相似文献   
999.
The effect of dietary vomitoxin on the serum IgA and IgG responses to two model intestinal antigens, casein and cholera toxin (CT), were assessed in 4 experimental groups: (1) mice fed casein-based diet, (2) mice fed casein-based diet containing 25 ppm vomitoxin, (3) mice fed casein-based diet and immunized with CT, and (4) mice fed casein-based diet containing 25 ppm vomitoxin and immunized with CT. Unimmunized and CT-immunized mice that were fed vomitoxin exhibited increased levels of total serum IgA relative to matched control animals fed the standard diet. Relative concentrations of casein-specific IgA were greater in both unimmunized mice and CT-immunized mice fed standard diet with vomitoxin than in matched controls fed standard diet only. CT-specific serum IgA in CT-immunized mice was not affected by vomitoxin feeding, but relative levels of CT-specific IgA were higher in unimmunized mice fed vomitoxin than in unimmunized mice fed standard diet. Both casein- and CT-specific serum IgG were depressed in mice fed vomitoxin. Significant differences in total, casein-specific and CT-specific IgA within the intestinal contents were not observed between CT-immunized mice fed vomitoxin and those fed the control diet. The results suggest that vomitoxin altered regulation of the normal immunoglobulin response to intestinal antigens and that this was manifested in the systemic compartment.  相似文献   
1000.
Since 1987, 80 hydroxyapatite-coated (HA) cementless total hip prostheses have been implanted. Thirty patients were examined 21 months postoperatively and the results compared with data for uncoated prosthesis. Earlier mobilization and freedom from pain, together with evidence of bone ingrowth without connective tissue membrane formation, confirmed the benefits of HA-coated prostheses.  相似文献   
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