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81.
Salt fluoridation is effective at inhibiting caries, but fluorosis prevalence data are deficient. OBJECTIVES: The purpose was to undertake a blind study of caries and tooth mottling in 8th grade school pupils from south-east Hungary who had resided (test) or not resided (control), until November 1985, in a 350 ppm F-/kg domestic salt-fluoridated area during their early years of life. METHODS: In Szeged, blind clinical caries and anterior tooth mottling scoring (+10% repeats) of 49 previously salt-fluoridated (mean age 14.14 years) and 59 non-salt-fluoridated subjects (mean age 14.08 years) were undertaken by one examiner, in June 1997. In addition, radiographic and photographic recordings were taken. In Glasgow, four dental and two lay staff scored the projected 35 mm colour transparencies (+10% repeats) of each pupil's six upper anterior teeth, for tooth mottling. All clinical, radiographic and photographic data were then analysed. RESULTS: Mean DMFS scores were 9.18 (SD=10.72) for test users and 4.51 (SD=6.24) for control users (P<0.01) and, based on repeat observations, clinical reliability=0.99; X-ray reliability=0.95. Clinically, three test children had fluorosis of 10 teeth, with eight teeth in two controls. Photographic scoring by the clinical examiner gave a 97.2% clinical match, while photographic agreements for all four dentist pairs were 92.5%-97.2%, with lay observers' agreements at 89.8%. For both groups, 10% repeats produced 98.5% agreements. In a sole test case "fluorosis" photographic unanimity was obtained, and non-unanimous "possible fluorosis" was recorded by two to four panel members for only three other test and two control subjects. CONCLUSIONS: No evidence was found that significant anterior tooth fluorosis resulted in subjects exposed previously to 350 ppm F-/kg domestic salt from birth to 2.3-4.8 years of age. However, no caries benefit was demonstrated after the 11.5-year salt fluoridation gap. Caries differences seemed social class-related, city-based controls having less disease than rural test subjects, in spite of an identical F- tablet regimen in all schools from 1987, until subjects were 10 years old. These data emphasise (a) the superiority of sustained community-delivered fluoridation and (b) the need to maintain constant fluoride delivery to tooth surfaces, certainly well beyond 10 years of age.  相似文献   
82.
An in vitro pH-cycling experiment was carried out to investigate the effect of fluoride concentration on enamel demineralization and remineralization. Artificial caries lesions were formed in an acid-buffered solution and subjected daily to a 3-hour acid attack, a 5-min immersion in the test NaF solution (0, 1, 250, 500, 1,000, 1,750 and 2,500 ppm F), and to 21 h in an artificial saliva. Changes in mineral content were assessed weekly for 5 weeks using microradiography/microdensitometry. The lesions in the control group (0 ppm F) and the 1-ppm F group demineralized. Remineralization was significantly higher in the 500-ppm F group compared to the 250-ppm F group. However, higher fluoride concentrations did not produce any further significant increase in remineralization. Laminations were apparent in lesions subjected to the 250- and 500-ppm F solutions.  相似文献   
83.
This investigation evaluated the retention of preformed posts with four different cements: C & B Metabond, Panavia, All-Bond 2, and Ketac-Cem. Sixty intact maxillary canines were selected for the study. The clinical crowns were removed and endodontic therapy done on each root, which was then prepared to receive prefabricated posts. The 60 samples were divided into four groups of 15, and the posts in each group were cemented with one of the four cements. The roots were mounted in acrylic resin blocks and the posts were separated from the canals with an Instron testing machine. Analysis of the forces needed to dislodge the posts with analysis of variance and Student-Newman-Keuls test disclosed that C & B Metabond cement was the most retentive (p < 0.05). No difference in retention was recorded between Ketac-Cem and Panavia cements. All-Bond 2 cement was the least retentive of cements.  相似文献   
84.
85.

Background

Recombinant activated Factor VII (rFVIIa) can be used for rapid INR normalization in patients with warfarin-associated intracranial hemorrhage (WA-ICH); however, the optimal dose to normalize INR has not been established.

Methods

This is a retrospective review comparing two rFVIIa hospital protocols for WA-ICH [weight-based dose (80 mcg/kg) or fixed dose (2 mg)]. Primary endpoint was the percentage of patients with INR reversal (INR <1.3) at the next INR draw and the need for further doses of rFVIIa. Secondary endpoints included time to documented INR reversal and sustained INR normalization, morbidity, mortality, change in hematoma size, cost, and adverse drug reactions.

Results

Twenty-nine patients were included in each group. The weight-based group received a mean dose of 78.9 ± 21 mcg/kg versus 26.6 ± 8 mcg/kg in the fixed dose group. More patients in the fixed dose protocol achieved documented INR reversal than those in the weight-based group (92.6 vs 72.4 %, p = 0.19). The weight-based group achieved INR normalization in 229.5 [102, 331] minutes versus 165 [83, 447] minutes in the fixed dose group (p=0.02). Time to sustained INR normalization was similar in both groups. Four patients in the fixed dose group received an additional dose of 1 mg per hospital protocol. With the exception of medication acquisition cost savings of about $4,300 per patient who received fixed dose protocol, all other endpoints were similar between groups.

Conclusions

A low, fixed dose of rFVIIa appears to be as effective as a high, weight-based dose in achieving INR normalization in patients with WA-ICH.  相似文献   
86.

Background

Femoroacetabular impingement (FAI) may constrain hip articulation and cause chondrolabral damage, but to our knowledge, in vivo articulation and femur-labrum contact patterns have not been quantified.

Purpose

In this exploratory study, we describe the use of high-speed dual-fluoroscopy and model-based tracking to dynamically measure in vivo hip articulation and estimate the location of femur-labrum contact in six asymptomatic hips and three hips with FAI during the impingement examination. We asked: (1) Does femur-labrum contact occur at the terminal position of impingement? (2) Could range of motion (ROM) during the impingement examination appear decreased in hips with FAI? (3) Does the location of femur-labrum contact coincide with that of minimum bone-to-bone distance? (4) In the patients with FAI, does the location of femur-labrum contact qualitatively correspond to the location of damage observed intraoperatively?

Methods

High-speed dual-fluoroscopy images were acquired continuously as the impingement examination was performed. CT arthrogram images of all subjects were segmented to generate three-dimensional (3-D) surfaces for the pelvis, femur, and labrum. Model-based tracking of the fluoroscopy images enabled dynamic kinematic observation of the 3-D surfaces. At the terminal position of the examination, the region of minimal bone-to-bone distance was compared with the estimated location of femur-labrum contact. Each patient with FAI underwent hip arthroscopy; the location of femur-labrum contact was compared qualitatively with damage found during surgery. As an exploratory study, statistics were not performed.

Results

Femur-labrum contact was observed in both groups, but patterns of contact were subject-specific. At the terminal position of the impingement examination, internal rotation and adduction angles for each of the patients with FAI were less than the 95% confidence intervals (CIs) for the asymptomatic control subjects. The location of minimum bone-to-bone distance agreed with the region of femur-labrum contact in two of nine hips. The locations of chondrolabral damage identified during surgery qualitatively coincided with the region of femur-labrum contact.

Conclusions

Dual-fluoroscopy and model-based tracking provided the ability to assess hip kinematics in vivo during the entire impingement examination. The high variability in observed labrum-femur contact patterns at the terminal position of the examination provides evidence that subtle anatomic features could dictate underlying hip biomechanics. Although femur-labrum contact occurs in asymptomatic and symptomatic hips at the terminal position of the impingement examination, contact may occur at reduced adduction and internal rotation in patients with FAI. Use of minimum bone-to-bone distance may not appropriately identify the region of femur-labrum contact. Additional research, using a larger cohort and appropriate statistical tests, is required to confirm the findings of this exploratory study.

Electronic supplementary material

The online version of this article (doi:10.1007/s11999-014-3919-9) contains supplementary material, which is available to authorized users.  相似文献   
87.

Background

Obesity is associated with reduced pulmonary function. We evaluated pulmonary function and status of asthma and obstructive sleep apnoea syndrome (OSAS) before and 5 years after bariatric surgery.

Methods

Spirometry was performed at baseline and 5 years postoperatively. Information of asthma and OSAS were recorded. Of 113 patients included, 101 had undergone gastric bypass, 10 duodenal switch and 2 sleeve gastrectomy.

Results

Eighty (71 %) patients were women, mean preoperative age was 40 years and preoperative weight was 133 kg in women and 158 kg in men. Five years postoperatively, weight reduction was 31 % (42 kg; p?<?0.001) in women and 24 % (38 kg; p?<?0.001) in men. Forced expiratory volume in 1 s (FEV1) increased 4.1 % (116 ml; p?<?0.001) in women and 6.7 % (238 ml; p?=?0.003) in men. Forced vital capacity (FVC) increased 5.8 % (209 ml; p?<?0.001) in women and 7.6 % (349 ml; p?<?0.001) in men. Gender and weight loss were independently associated with the improvements in FEV1 and FVC. At follow-up, FEV1 had increased 36 % of the difference towards the estimated normal FEV1, and there was a corresponding 70 % recovery of FVC. These improvements occurred despite an expected decline in pulmonary function by age during the study period. Of the asthmatics and OSAS patients, 48 and 80 %, respectively, were without symptoms 5 years postoperatively.

Conclusions

Pulmonary function measured with spirometry was significantly improved 5 years after bariatric surgery, despite an expected age-related decline during this period. Symptoms of asthma and OSAS also improved.  相似文献   
88.

Introduction and hypothesis

The aim was to evaluate the relationship between age and the impact of pelvic floor disorders (PFD) using a multi-dimensional pelvic floor questionnaire

Methods

Questionnaire data on 4,311 women attending urogynaecology clinics with PFD were stratified by age into four groups: ≤35, 36–50, 51–65 and >65 years. The symptom frequency (ranging from 0 to 100) was divided in to mild (0–33), moderate (34–67), and severe (68–100) symptoms. Impact scores for equivalent levels of symptom frequency (mild, moderate and severe symptoms) were compared in women of different ages.

Results

Overall, bowel continence was associated with the greatest bother and constipation the least. Older women were significantly less bothered by mild to moderate urinary, bowel and vaginal symptoms (except IBS and vaginal capacity) than younger women. There was no difference in the impact of severe symptoms in different ages. In contrast, for sexual symptoms, there was a significant difference in the impact in older women for all grades of severity.

Conclusions

Women’s views and attitudes towards symptoms are variable and age is a significant factor. In women attending urogynaecology clinics with pelvic floor symptoms the impact of most symptoms (particularly sexual dysfunction) become less bothersome with age.  相似文献   
89.
Incident pain related to bone metastases is a problematic symptom to treat. The difficulty in treating this type of pain is reflected in the wide variety of treatment modalities recommended. The aims of this prospective observational study were to determine the patterns of pain severity at rest and on movement over time and which treatment modalities are employed. In addition, we were interested in ascertaining any correlations between bone pain at rest, bone pain on movement and functional ability. Thirty-two patients were followed up for a mean of 22 weeks (range: 2-52). In total, there were 704 patient follow-up weeks. Patients were followed up for one year or until death. A total of 19 different treatment modalities were employed. There were strong correlations between pain at rest and pain on movement. There were no significant correlations between functional ability and pain at rest or movement. Our study demonstrates the complex management of patients with bone pain. This is the first study that highlights the correlation between pain at rest and pain on movement in patients with bone metastases in a palliative care population. It highlights the need for intensive follow-up of these patients, as they require multiple interventions to help control their pain. These data can also be used to power further interventional studies.  相似文献   
90.
Hypoglycemia in diabetes   总被引:33,自引:0,他引:33  
Cryer PE  Davis SN  Shamoon H 《Diabetes care》2003,26(6):1902-1912
Iatrogenic hypoglycemia causes recurrent morbidity in most people with type 1 diabetes and many with type 2 diabetes, and it is sometimes fatal. The barrier of hypoglycemia generally precludes maintenance of euglycemia over a lifetime of diabetes and thus precludes full realization of euglycemia's long-term benefits. While the clinical presentation is often characteristic, particularly for the experienced individual with diabetes, the neurogenic and neuroglycopenic symptoms of hypoglycemia are nonspecific and relatively insensitive; therefore, many episodes are not recognized. Hypoglycemia can result from exogenous or endogenous insulin excess alone. However, iatrogenic hypoglycemia is typically the result of the interplay of absolute or relative insulin excess and compromised glucose counterregulation in type 1 and advanced type 2 diabetes. Decrements in insulin, increments in glucagon, and, absent the latter, increments in epinephrine stand high in the hierarchy of redundant glucose counterregulatory factors that normally prevent or rapidly correct hypoglycemia. In insulin-deficient diabetes (exogenous) insulin levels do not decrease as glucose levels fall, and the combination of deficient glucagon and epinephrine responses causes defective glucose counterregulation. Reduced sympathoadrenal responses cause hypoglycemia unawareness. The concept of hypoglycemia-associated autonomic failure in diabetes posits that recent antecedent hypoglycemia causes both defective glucose counterregulation and hypoglycemia unawareness. By shifting glycemic thresholds for the sympathoadrenal (including epinephrine) and the resulting neurogenic responses to lower plasma glucose concentrations, antecedent hypoglycemia leads to a vicious cycle of recurrent hypoglycemia and further impairment of glucose counterregulation. Thus, short-term avoidance of hypoglycemia reverses hypoglycemia unawareness in most affected patients. The clinical approach to minimizing hypoglycemia while improving glycemic control includes 1) addressing the issue, 2) applying the principles of aggressive glycemic therapy, including flexible and individualized drug regimens, and 3) considering the risk factors for iatrogenic hypoglycemia. The latter include factors that result in absolute or relative insulin excess: drug dose, timing, and type; patterns of food ingestion and exercise; interactions with alcohol and other drugs; and altered sensitivity to or clearance of insulin. They also include factors that are clinical surrogates of compromised glucose counterregulation: endogenous insulin deficiency; history of severe hypoglycemia, hypoglycemia unawareness, or both; and aggressive glycemic therapy per se, as evidenced by lower HbA(1c) levels, lower glycemic goals, or both. In a patient with hypoglycemia unawareness (which implies recurrent hypoglycemia) a 2- to 3-week period of scrupulous avoidance of hypoglycemia is advisable. Pending the prevention and cure of diabetes or the development of methods that provide glucose-regulated insulin replacement or secretion, we need to learn to replace insulin in a much more physiological fashion, to prevent, correct, or compensate for compromised glucose counterregulation, or both if we are to achieve near-euglycemia safely in most people with diabetes.  相似文献   
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