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1.
A simple method that used headgear and a functional appliance simultaneously was used for the correction of Class II, Division 1 cases with severe denture base discrepancy. The treatment restricted the forward growth of the maxilla and advanced the mandible. The functional appliance, referred to as the mandibular growth advancer (MGA), advances the mandible progressively with a splint, with the objective of remodeling the condyle and the glenoid fossa in the temporomandibular joint. Functional adaptation was achieved as the muscles that are attached to the mandible adjusted to new positions. In the two cases that illustrate this method, the ANB angle decreased and the Ar-B distance increased over a short period to four and six times the mean Japanese growth rate, respectively. After the correction of the denture-base discrepancy, a multibracket fixed appliance was used for dental alignment, and good skeletal, occlusal relationships and profiles were obtained. Treatment of severe denture-base discrepancy in this manner may reduce the skeletal abnormality, decrease the number of extraction cases, and shorten the subsequent multibracket treatment time. And it may reduce the iatrogenic side effects caused by prolonged mechanotherapy with a fixed appliance.  相似文献   

2.
Selection of the treatment method of choice in orthodontics is usually a question of the clinician's personal preference and is generally based on subjective criteria. Orthodontic treatment of malocclusions is unlike treatment of a disease and hence terms such as success and failure are relative and undefined. Ideally, both patients and providers should be able to arrive at treatment decisions that have the greatest potential for optimum outcomes at minimal cost and risks. This article applies the method of decision analysis to demonstrate how policy choices between "one-stage" or "two-stage" treatment of Class II Division 1 malocclusions for children between 11 and 14 years old can be based on objective criteria. A decision tree was designed to yield the value of payoffs, or outcomes, at each of the possible terminal nodes, and the probability of each payoff. Both positive (ie, improvement in malocclusion) and negative (ie, extraction of teeth and long treatment duration) attributes of outcomes were considered, and numerical values, or "utilities," were assigned to each outcome. For this model, one-stage nonextraction treatment yields the highest probability of maximum benefit. Further applications of decision analysis to resolve clinical uncertainties in orthodontics are discussed.  相似文献   

3.
To identify the characteristics and extent of orbitocranial tumor for the selection of operative methods, 64 patients with the tumor were studied with clinical materials, primarily CT and magnetic resonance imaging (MRI) appearances. The lesions were found in the orbit, cranium and orbito-cranium boundary parts and their diagnoses in regard to localization and identification could be made. Based on the preoperative diagnosis of an orbito-cranial tumor, its location, character, secondary changes and operation(s) in the past, a surgical approach was designed. The resection of a tumor could be completed in once or in several times of operation. 64 operations were performed on 53 patients and other therapies were given to the other 11 patients. The operative methods included orbitotomy via anterior route, 21 times via lateral route and 30 times via transcranial route. The operative results suggest that the transcranial route be complicated and have more complications; preoperatively, the operative indication be strictly selected and intraoperatively, ophthalmologists closely cooperate with neurological surgeons.  相似文献   

4.
This case report analyzes long-term occlusal stability that can be achieved in Class II, Division 1, deep bite cases with active treatment finished during the period of maxillomandibular growth. The analysis was designed to identify occlusal features common to two cases at the end of active treatment and to study how the occlusion changed with growth and jaw movement to achieve stability. The following occlusal features were shared by the two cases at the end of active treatment: (1) AB plane and axes of the maxillary and mandibular posterior teeth were perpendicular to functional occlusal plane; (2) the axis of the lower incisor was almost perpendicular to DC-L1i line; (3) the anterior occlusion was overcorrected to or near an edge-to-edge relationship. Items 1 and 2 remained unchanged throughout the follow-up periods, regardless of growth status, and the overjet and overbite increased during maxillomandibular growth after treatment. During the period of mandibular growth alone, after the end of retention, the axes of maxillary incisors tipped labially; as a result, F line became parallel to CDM line by the end of growth. The labial tipping of maxillary incisors brought the lower incisal edge into contact with or extremely near the inflection point (Bp).1 By the end of growth, the tangent of Bp became parallel to or coincident with DC-L1i line and perpendicular to the axis of the lower incisor, and the DC-L1i lines at various times posttreatment were almost parallel to each other in the two cases. Overjet increased as the maxillary incisors tipped labially, providing proper protrusive and retrusive paths for mandibular guidance. The angle between the functional occlusal plane and CDM line stayed almost the same as at the end of active treatment in the two cases, suggesting a possible change in the angle of eminence in harmony with the functional occlusal plane. These factors apparently contributed to the long-term occlusal stability in the two cases.  相似文献   

5.
Longitudinal records from the Ohio State University Growth Study were used to compare the skeletal growth changes between Class II division 1 and Class I female subjects between ages 7 and 14. Tensor analysis was used to determine the yearly growth rate and direction. No significant difference was found in cranial base dimension between the Class I and Class II subjects. In Class II subjects, the maxilla (S-N-A) was found to be normally related to the cranial base. However, mandibular position (S-N-B and S-N-Pog) was found to be significantly more retrusive in Class II when compared with Class I subjects. Mandibular length (Ar-Gn) and corpus length (Go-Gn) were found to be shorter in Class II subjects. The ratio of PFH to AFH was found to be smaller in Class II subjects. This is particularly apparent during the pubertal growth period. The y-axis and mandibular plane angle were more open in Class II subjects which also contributed to the retrusive position of the mandible. Maxillo-mandibular difference (A-N-B) between Class I and II subjects was present at age 7 and persisted through puberty, maintaining a greater angle of convexity (A-N-Pg) in Class II subjects. These results suggest that Class II malocclusion can be detected early. The majority of the Class II cases showed mandibular skeletal retrusion or a combination of horizontal and vertical abnormalities of the mandible rather than maxillary protrusion. These skeletal differences remain through puberty without orthodontic intervention. Individual variations were found within each type of malocclusion.  相似文献   

6.
Needlestick injuries, which lead to the transmission of hepatitis B, hepatitis C, and the AIDS virus, are a potentially serious threat to students during their clinical experiences. Exposure to infectious diseases, blood, and hazardous body fluids is one of the most frequently reported injury events by medical students at a health science center in the southwestern region of the United States. This study was conducted to determine the effectiveness of a customized intervention about infection control for second-year medical students (N = 200). Preparation for the intervention included a needs assessment, which included both qualitative and quantitative research methods that incorporated input from fourth-year medical students, medical staff members, and local hospital infection control specialists. The intervention included a pretest, a lecture, a demonstration of standard precautions and infection control procedure with 2 clinical scenarios, an exercise on proper handwashing, and a posttest. The evaluation of the intervention demonstrated a significant increase in posttest knowledge scores about infection control (from 12.6 +/- 2.1 pretest to 16.5 +/- 1.8 posttest, P < .001). Medical students showed a significant knowledge increase about infection control after participating in the intervention . Thus we recommend that all medical colleges and universities develop and evaluate a similar customized intervention for their medical students.  相似文献   

7.
Two live attenuated single-deletion mutant simian immunodeficiency virus (SIV) constructs, SIV239Deltanef and SIVPBj6.6Deltanef, were tested for their abilities to stimulate protective immunity in macaques. During the immunization period the animals were examined for specific immune responses and virus growth. Each construct generated high levels of specific immunity in all of the immunized animals. The SIV239Deltanef construct was found to grow to high levels in all immunized animals, with some animals remaining positive for virus isolation and plasma RNA throughout the immunization period. The SIVPBj6.6Deltanef was effectively controlled by all of the immunized animals, with virus mostly isolated only during the first few months following immunization and plasma RNA never detected. Following an extended period of immunization of over 80 weeks, the animals were challenged with a pathogenic simian-human immunodeficiency virus (SHIV) isolate, SIV89. 6PD, by intravenous injection. All of the SIV239Deltanef-immunized animals became infected with the SHIV isolate; two of five animals eventually controlled the challenge and three of five animals, which failed to check the immunizing virus, progressed to disease state before the unvaccinated controls. One of five animals immunized with SIVPBj6.6Deltanef totally resisted infection by the challenge virus, while three others limited its growth and the remaining animal became persistently infected and eventually died of a pulmonary thrombus. These data indicate that vaccination with attenuated SIV can protect macaques from disease and in some cases from infection by a divergent SHIV. However, if animals are unable to control the immunizing virus, potential damage that can accelerate the disease course of a pathogenic challenge virus may occur.  相似文献   

8.
The president of APA's Division Two suggests that those who teach psychology can make contributions to psychologist-scholars in theoretical and philosophical psychology. She indicates that members of Division Two could use some help in learning to think differently about the psychology they teach and specifically about the ways in which they try to teach theoretical and philosophical issues in psychology. For Division Two's part, she believes that their members could reciprocate with additional insights that might help Division 24's students learn. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

9.
通过对煤气加压站煤气泄漏源点的分析和确认,并对其泄漏源点采取充氮密封和局部强制通风等手段,以达到降低煤气区域爆炸等级的目的,并对煤气加压站防爆等级进行了探讨性划分。  相似文献   

10.
Sensitivity and specificity are key measures of the performance of a given test in detecting a given disorder. For tests yielding numerical scores, sensitivity and specificity usually vary inversely over the range of theoretically possible cutoff scores, complicating the task of quantifying and comparing the diagnostic accuracy of tests. Receiver Operating Characteristic analysis (ROC) approaches this problem by plotting the curve of sensitivity versus 1-specificity for all possible cutoff scores of the test. The area under the ROC curve (AUC) can be used to describe the diagnostic accuracy of the test. Parametric and non-parametric methods exist that allow the calculation of the AUC and the comparison of tests. A disadvantage of parametric formulations is the assumption of a normal or Gaussian distribution of test scores. The present article presents a computer program that utilizes non-parametric formulations that do not require the normal distribution of test scores. The program calculates the sensitivity and specificity of a test at all possible cutoff scores, plots the ROC curve, calculates the AUC, its standard error and 95% confidence limits, and allows the comparison of tests on independent and correlated samples.  相似文献   

11.
12.
IgG antibodies from the sera of some patients with bullous pemphigoid (BP) react with a 180 kDa protein termed BPAg2. Antibodies in BP are directed to an extracellular noncollagenous domain of this protein termed NC16A. Our group has recently shown that a portion of the extracellular domain of BPAg2 is identical to LABD97 on the basis of amino acid sequencing. We evaluated sera from 33 patients with BP with circulating IgG antibodies on indirect immunofluorescence, which stained the epidermal side of split skin with titers ranging from 1:40 to 1:640. Immunoblotting was performed against (i) two preparations of proteins from epidermal extract, one containing BPAg2 and one containing LABD97, and (ii) the recombinant NC16A domain of the BPAg2 protein. Twelve sera reacted with the BPAg2 protein. Ten of these also reacted strongly with the NC16A domain. Nine of the 12 sera also reacted with the LABD97 antigen. Bound antibodies were eluted from the 97 kDa band and reapplied to split skin where they bound to the epidermal side. The eluted antibodies also reacted to the BPAg2 protein from the epidermal extract, but did not react with the NC16A domain on immunoblot. We conclude that these nine sera react with an epitope present within BPAg2 and LABD97 but not within the NC16A domain. This epitope is therefore distal to the previously described epitopes in BP. In BP, epitope spreading may occur and antibodies may be produced that recognize the distal portion of the BPAg2 molecule identical to LABD97 but that do not involve the NC16A domain.  相似文献   

13.
A magnetically active, two-piece (upper and lower), functional orthopedic appliance has been developed, magnetic activator device (MAD) for the correction of Class II malocclusions. The magnetic forces are used to give freedom of mandibular movement and to allow for continuous functioning of the orofacial muscles when the appliance is worn. Samarium cobalt (Sm2Co17) magnets are incorporated on the buccal aspects of the upper and lower appliances. Magnetic forces ranging from 150 to 600 gm per side have been used on patients, and it seems that the skeletal versus dental response depends on the intensity of the magnetic force used. A force of 300 gm, when the magnets are in contact, on each side has been found to be an appropriate value in patients age 7 to 12 years. The use of this less bulky design rather than a traditional orthopedic appliance, along with the freedom of function it permits, has enabled patients to wear the appliance nearly 24 hours in most cases.  相似文献   

14.
Children with pelvic fractures usually are polytraumatized. Concomitant abdominal and pelvic injuries are not uncommon. Medical records and X-rays of 54 children, in which a pelvic fracture was diagnosed at our institution from 1974-1993, were reviewed. Children ages < or = 16 years and treated as in-patients were included in this study. The fractures were classified according to the AO-Classification. 47 patients (87.0%) had concomitant injuries. The mean Polytrauma Score was 23.7 (mean Injury Severity Score 30.5). Nine Children sustained an open pelvic fracture with rectal and/or vaginal tear. 15 genitourinary lesions were found in 13 children. 18 patients underwent laparotomy. A large pelvic/retroperitoneal hematoma was found in 11 cases. There were 7 liver lacerations, 7 splenic injuries, 2 mesenteric tears, 2 kidney injuries and 1 small bowel lesion. Eight children (14.8%) died with 5 of them due to retroperitoneal or/and abdominal bleeding complications. A recent follow-up examination (81.8%) with a mean follow-up of 11.3 years showed that long-term morbidity usually was attributed to pelvic concomitant injuries.  相似文献   

15.
16.
1. The incorporation of L-[U-14C]leucine, L[U-14C]histidine and L-[U-14C]phenylalanine into casein secreted during perfusion of isolated guinea-pig mammary glands was demonstrated. 2. The extent of incorporation of label into casein residues was consistent with their being derived from free amino acids of the perfusate plasma. 3. The mean transit time of the amino acids from perfusate into secreted casein was approx. 100 min. 4. Whereas radioactive histidine and phenylalanine were incorporated solely into milk protein, radioactivity from [U-14C]valine was also transferred to CO2 and to an unidentified plasma component, and from [U-14C]leucine to plasma glutamic acid. 5. Evidence from experiments with [U-14C]phenylalanine suggests that, as in rats, but in contrast with ruminant species, guinea-pig mammary tissue does not possess phenyl alanine hydroxylase activity. 6. The results are discussed in relation to the possible role of essential amino acid catabolism in the control of milk-protein synthesis.  相似文献   

17.
本文总结了一期焦炉炉体维护与热修的经验与教训,分析焦炉维护与热修技术对焦炉寿命的影响,对晚期焦炉维护与热修的方针及措施进行了探索。  相似文献   

18.
Unilateral torsion of the spermatic cord has been demonstrated to damage the contralateral testis; however, the pathogenesis has not yet been examined in detail. The purpose of this study was to evaluate the influence of unilateral torsion on the contralateral testis in rats by performing ipsilateral division of the genitofemoral nerve (GFN) and/or late orchiectomy. Male 25-day-old, prepubertal Wistar albino rats were divided into five groups: (1) sham operation; (2) unilateral testicular torsion; (3) simultaneous unilateral testicular torsion and ipsilateral GFN division; (4) unilateral testicular torsion and orchiectomy on the 4th day after torsion; and (5) simultaneous unilateral testicular torsion and GFN ipsilateral division, and orchiectomy on the 4th day after torsion. Torsions performed were 720 degrees, all on the right testes. On day 55 after torsion, which represents the early postpubertal period of the rat, the contralateral testes were removed. Tubular biopsy score (TBS) was calculated, and seminiferous tubular diameters (STD) were measured. Student's t-test was used for statistical analysis. There was no contralateral testicular damage in the control group, but in all of the study groups destructive changes were found in the left gonad after torsion of the right testicle. The mean TBS of the study groups was higher than that of the control group. STD values were lower in the study groups, but the differences were not statistically significant between groups. In prepubertal rats, unilateral torsion causes histologically measurable changes in the contralateral testis. Ipsilateral division of the GFN and late orchiectomy did not cause any significant alterations in terms of contralateral damage. Further investigations are needed to determine the role of the GFN in testicular torsion.  相似文献   

19.
The purpose of this study was to evaluate the efficacy of a trapezoidal wave form for ventricular difibrillation. Overall efficacy showed the trapezoidal waveform to be effective for defibrillation, including patients weighing over 100 kg (220 lb). We concluded that (1) the trapezoidal waveform is an effective defibrillatory pulse and (2) the trapezoidal waveform offers pulse characteristics less deleterious than other established waveforms.  相似文献   

20.
Nurse executive are well positioned to be the entrepreneurial spirit needed to help their organization adapt to a rapidly changing health care industry. The article suggests a foundation to help nurse executives expand their entrepreneurial role. Areas for consideration and development include awareness, environment, education, characteristics and principles.  相似文献   

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