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1.
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   
2.
The analgesic efficacy of a lidocaine/prilocaine cream (EMLA) for the cautery of genital warts was evaluated in an open study. Fifty-two women aged 18 to 28 with at least two condylomata on the vulval mucosa took part. In a pilot study (n = 10) the time of onset of anaesthesia after the application of EMLA to the mucosa was established by pinching with a forceps. All ten patients were anaesthetized within 5-7 min and cautery was performed with no or only slight pain in 9/10 patients. In the main study EMLA was applied to the mucosa of 42 women for 10, 15 or 20 min. The anaesthesia was satisfactory for the cautery of condylomata in 92% of the patients after the application of EMLA for 10 minutes. The analgesic efficacy decreased gradually with application times of 15 min or longer (p less than 0.05). In the case of insufficient anaesthesia, an additional application of EMLA for 2-5 min enabled the operations to be completed in 7/8 patients.  相似文献   
3.
Psychiatric disturbances are common in primary hyperparathyroidism (HPT), but their pathogenesis is essentially unknown. This study deals with cerebrospinal fluid (CSF) calcium homeostasis and its connection with parathyroid hormone (PTH), blood-brain barrier (BBB) function, and central monoamine and purine metabolites in patients with primary HPT. In 22 patients with primary HPT (serum calcium 2.85 +/- 0.21 mmol/l), the CSF concentrations of total and ionized calcium were higher (1.21 +/- 0.08 mmol/l, p less than 0.01, and 1.09 +/- 0.05 mmol/l, p less than 0.001, respectively) than in 11 normocalcemic reference subjects. The values correlated with serum calcium concentration (p less than 0.001) and CSF/serum albumin ratio, a measure of BBB permeability. The latter ratio was elevated in one-third of the patients with HPT, indicating BBB damage. CSF immunoreactive intact PTH was higher in the HPT patients than in the reference group (p less than 0.05), and serum and CSF PTH were positively correlated (p less than 0.05). The CSF levels of the monoamine metabolites 5-hydroxyindoleacetic acid (5HIAA) and homovanillic acid (HVA) were lower, and the level of urate in CSF was higher, in the HPT patients than in the reference subjects, while there were no consistent differences in CSF hypoxanthine or xanthine. CSF 5HIAA correlated inversely with CSF ionized calcium (r = -0.42, p = 0.02). After parathyroid surgery, CSF calcium and urate decreased significantly and CSF monoamine metabolites increased slightly. The decrease in CSF ionized calcium correlated with the alleviation of psychiatric symptoms. The results indicate the importance of increased CSF calcium concentrations in patients with primary HPT and suggest a relation between central calcium regulation and central turnover of monoamines.  相似文献   
4.
In a prospective population-based investigation, we measured bone mineral density (BMD) of the forearm using single-photon absorptiometry at both a distal and a more proximal site in 74 Colles'-fracture patients who were compared with controls matched for age, sex, and years after menopause. For both groups there was a marked inverse relationship between age and bone mass. However, over the entire age range, the probands had 11 percent reduced BMD when compared with the controls. Our findings confirm that patients with fracture of the distal forearm have reduced BMD. They constitute an appropriate group for studies aimed at prevention of fracture in the elderly.  相似文献   
5.
Dubbelman and co-workers have determined intraocular spacings and surface shapes in living eyes by means of corrected Scheimpflug images in a large number of subjects of different age at several levels of accommodation. They give relationships for key anterior segment parameters as a function of age and level of accommodation. These are used in this paper to build a schematic eye incorporating aspheric surfaces. This eye model is analysed by means of ray tracing with a technique developed for use with a common spreadsheet computer program. The Dubbelman eye model appears to be well corrected for spherical aberration. Compared with measurements on real eyes it agrees well in general, but spherical aberration is negative, while in real eyes it tends to be positive.  相似文献   
6.
Pieces of rat parathyroid glands were used to study fluxes of 45Ca and 86Rb. The uptake of 45Ca increased with the extracellular Ca2+ concentration up to at least 5 mM. A rise of extracellular Ca2+ had dual effects on 45Ca efflux in terms of an initial stimulation and a subsequent inhibition. However, K+ depolarization neither affected the uptake nor the efflux of 45Ca indicating a lack of voltage-dependent Ca2+ channels. The depolarization obtained with exposure to Ca2+ cannot be attributed to a decreased K+ permeability, since the 86Rb concentrating ability diminished and the efflux of the isotope increased when parathyroid pieces were exposed to a raised Ca2+ concentration. A stimulation of 86Rb efflux by the Ca2+ ionophore A-23187 indicated that the parathyroid cells possess a K+ permeability activated by cytoplasmic Ca2+. It is suggested that Ca2+ fluxes through channels sensitive to activation by Ca2+ are important both for the membrane potential and the cytoplasmic Ca2+ activity.  相似文献   
7.
A systematic review of radiation therapy trials in several tumour types was performed by The Swedish Council of Technology Assessment in Health Care (SBU). The procedures for evaluation of the scientific literature are described separately (Acta Oncol 2003; 42: 357-365). This synthesis of the literature on radiation therapy for urinary bladder cancer is based on data from 3 meta-analyses and 33 randomized trials. The studies include 4 333 patients. The results were compared with those of a similar overview from 1996 including 15 042 patients. The conclusions reached can be summarized as these points: There is moderate evidence for an overall survival benefit with preoperative radiotherapy followed by cystectomy compared to curative radiotherapy based on early studies (1964-1986). Since that time surgical as well as radiation techniques have developed considerably. Therefore, the conclusion may not be relevant to modern treatment of invasive urinary bladder carcinoma.There is only one small study reporting on curative radiotherapy where increased dose per fraction is compared with conventionally fractionated radiotherapy to the same total dose. Thus, no conclusions can be drawn concerning optimal fraction dose.A meta-analysis based on two studies on hyperfractionated radiotherapy gives moderate evidence of a survival benefit at 5 and 10 years and an increased local control rate compared with conventional fractionation.The documentation of local control and overall survival rate after split-course radiation treatment compared to continuous therapy is conflicting. No firm conclusions can be drawn.Four small and early studies have compared radiation treatment using neutrons with photon treatment. The reports favour therapy with photons with respect to overall treatment results. There is moderate evidence for this conclusion.There is fairly strong evidence in early studies that radiation treatment in combination with hyperbaric oxygen does not confer a treatment benefit compared to radiation in normal atmosphere.There is no indication of a treatment benefit with the addition of either hyperthermia or misonidazole.A large number of phase II studies, suggesting an increased possibility for bladder preservation with concomitant chemoradiotherapy compared to radiotherapy alone, have been reviewed in a previous SBU report on chemotherapy. Only one small randomized study has been reported where concomitant chemoradiotherapy with cisplatin is compared to radiation alone. No conclusion on the therapeutic benefit of combined treatment can be drawn. Large randomized studies are needed.There is some evidence that preoperative radiotherapy followed by cystectomy does not confer any significant survival benefit compared to cystectomy alone.There is moderate evidence that palliative radiotherapy of invasive bladder carcinoma can rapidly induce tumour-related symptom relief.There is moderate evidence that palliative hypofractionated radiotherapy, 3 fractions during one week, gives the same relief of symptoms as 10 fractions during 2 weeks.  相似文献   
8.
PURPOSE: The aim of this study was to design and evaluate in the laboratory a new intraocular lens (IOL) intended to provide superior ocular optical quality by reducing spherical aberration. METHODS: Corneal topography measurements were performed on 71 cataract patients using an Orbscan I. The measured corneal surface shapes were used to determine the wavefront aberration of each cornea. A model cornea was then designed to reproduce the measured average spherical aberration. This model cornea was used to design IOLs having a fixed amount of negative spherical aberration that partially compensates for the average positive spherical aberration of the cornea. Theoretical and physical eye models were used to assess the expected improvement in optical quality of an eye implanted with this lens. RESULTS: Measurements of optical quality provided evidence that if this modified prolate IOL was centered within 0.4 mm and tilted less than 7 degrees, it would exceed the optical performance of a conventional spherical IOL. This improvement occurred without an apparent loss in depth of focus. CONCLUSION: A new IOL with a prolate anterior surface, designed to partially compensate for the average spherical aberration of the cornea, is intended to improve the ocular optical quality of pseudophakic patients.  相似文献   
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