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991.
992.
A total of 79 consecutive patients with pituitary tumours were screened for multiple endocrine neoplasia type 1 (MEN-1). The 79 patients included 21 patients with acromegaly, nine with Cushing's disease, 18 with prolactinomas, three with mixed pituitary adenomas (GH and PRL), and 28 patients with no detectable hypersecretion of hormones. The screening consisted of: (1) a family history, (2) a uniform medical history of the patient using a standard questionnaire, and (3) hormonal evaluation including measurements of the serum levels of insulin, gastrin, glucagon, somatostatin, vasoactive intestinal polypeptide and pancreatic polypeptide. Ionized calcium and glucose concentration in serum were also measured. We found no patients with the MEN-1 syndrome. In one patient, we found a transient elevation of serum concentrations of pancreatic polypeptide for which we have no explanation. In another patient, the serum gastrin concentration was elevated secondary to achlorhydria. No other endocrine disorders were found, and no patients had relatives with recognized endocrine pancreatic tumours, primary hyperparathyroidism (HPT), or pituitary adenomas.  相似文献   
993.
388 13-yr-old schoolchildren from Karlstad, Sweden, participated. Dental caries experience was expressed as number of decayed (D) and filled (F) tooth surfaces (S), and registered on bite-wing radiographs and obtained from records. Salivary Streptococcus mutans counts were determined by a spatula method. A dietary score was calculated for each individual based on an interview concerning the intake frequency of 23 sugar-containing products. Significantly lower DFS values were found in the group with no detectable S. mutans compared to three of the four groups with salivary S. mutans (P less than 0.01). No differences were found between the DFS values of individuals with high, moderate or low dietary scores. There was no statistically significant association between dietary scores and levels of S. mutans. Among the children with no detectable S. mutans, there were higher DFS-values with increasing intake frequency. No relationship between initial caries lesions, S. mutans and diet was found.  相似文献   
994.
A sociological study was conducted in 1987 on a sample of 490 Hong Kong Chinese civil servants for the purpose of investigating factors which influenced their utilization of a freely available Government dental service. The proportions of regular, irregular and non-users of the dental service were 69, 18, and 13% respectively. Regular users had a higher educational standard and income level than the other two user-types. Most of the regular users attended the dental clinics for a check-up. The irregular users did not regularly utilize the service mainly because it took a long time to obtain an appointment. Non-users referred to the long waiting time to obtain an appointment and to their perception of not having dental problems when asked to give their main reasons for not utilizing the dental service. The majority of the user-types considered that shortening the waiting time and employing more dentists would increase the utilization of the Government dental service.  相似文献   
995.
996.
997.
Summary Fifteen years after their forearm bone mineral content was measured, 366 women were measured again with the same single photon technique. 96 of the women had sustained one or more fragility fractures during that period. The initial bone mineral content was less in those women who were to have fractures. The rate of loss over the years did not differ between fracture and non-fracture women—the initial bone mass was the better predictor. Peak bone mass in the women in this study occurred before the age of 40.  相似文献   
998.
999.
In inverse radiotherapy planning, the traditional dose planning sequence is reversed. This makes it possible to calculate the optimal incident beam profiles required to produce the desired dose distribution in the target volume by solving an integral equation with an iterative algorithm. The major advantage, compared with conventional treatment planning, is that the trial and error part is avoided, and replaced by a deterministic calculation of the optimal treatment plan. In the present paper this algorithm is briefly described and compared with experimental results and an analytical inversion formula which is valid for a cylindrical geometry. The experiments were performed with non-homogeneous beams shaped with compensators designed using the algorithm. The agreement between the experimental results and the predictions of the algorithm are quite good, generally within about 5%. The differences are caused by discretization noise due to the finite resolution of the calculation matrix, imperfections in the experimental situation, and by the assumption of spatial invariant dose distribution kernels.  相似文献   
1000.
Rabbits were injected either intravenously or intramuscularly with [14C]haem arginate and [59Fe]haem arginate (haem 5 mg kg-1). The main part (80%) of AUCINF of labelled haem was associated with the beta-phase, T1/2 being about 6 h. Only 1% of the haem dose had been taken up by the red blood cells. In contrast, the iron moiety from the haem molecule was effectively utilized. Thirty days post-injection of [59Fe]haem arginate, 40% of the dose after intravenous injection and 60% after intramuscular injection was circulating with the red cells. Radioactivity was shown to concentrate in the liver, where haem is mainly metabolized and eliminated. An accumulation of haem in the adrenals was also evident. Haem itself did not concentrate in the bone marrow, and a negligible amount of radioactivity was recovered from brain, implying a poor penetration of the blood brain barrier.  相似文献   
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