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1.
Endoscopically controlled sinus floor augmentation. A preliminary report.   总被引:1,自引:0,他引:1  
Sinus augmentation has been advocated to be a surgical technique with predictable results in peri‐implant surgery. Endoscopic surgery of the maxillary sinus so far has been used as diagnostic procedure. In this paper, the use of endoscopy is described as a low invasive adjunctive technique in sinus floor augmentation. After preparation of the mucoperiosteum, bone grafts can be placed under endoscopic control between sinus floor and mucoperiosteum. A laterobasal approach via a small osteotomy and a transalveolar approach are possible for mucosal elevation and graft placement. First clinical results are reported. Endoscopic sinus lift may contribute to a reduction of perioperative morbidity, reduction of oroantal fistulae and control of graft position. The less invasive technique may allow to extend the indication for sinus augmentation.  相似文献   
2.
A 144cerium-induced osteosarcoma was transplanted to athymic nude rats (Han:rnu/rnu). Nineteen of the tumor-bearing animals were used to demonstrate the characteristics of the osteosarcoma on magnetic resonance imaging (MRI) in comparison with a group of nine animals that had not received any tumor transplant. The tumor-free animals showed homogeneous results in the measurements of their lower legs (T1, 800-898 mseconds; T2, 33-45 mseconds). The osteosarcomas of the tumor-bearing rats were clearly demonstrated and delineated from adjacent structures by MRI at tumor volumes between 0.3 and 7.5 cm3. A significant increase in T1 and T2 relaxation times was found, which corresponded to the increase in tumor volume. T1 relaxation times decreased slightly when tumor volumes reached greater than 5 cm3, whereas T2 relaxation times remained constant at tumor volumes greater than 2.5 cm3. Histologic changes in the structure of the tumors, occurring naturally during their growth, were proven by immersion-fixed sections embedded in paraffin and stained with hematoxylin-eosin. The water content of small and large tumors was determined by lyophilization and heat drying. Both histologic changes and differences in water content were reflected in the variations of relaxation times.  相似文献   
3.
We investigated the effects of ice massage, ice massage with exercise, and exercise on the prevention and treatment of delayed onset muscle soreness (DOMS). Twenty-two subjects were randomly assigned to one of four groups. Preexercise measures were recorded for range of motion (ROM), strength, perceived soreness, and serum creatine kinase (CK) levels. Subjects performed up to 300 concentric/eccentric contractions of the elbow flexors with 90% of their 10 repetition maximum to induce muscle soreness. Dependent variables were assessed at 2, 4, 6, 24, 48, 72, 96, and 120 hours postexercise. Significant differences occurred in all variables with respect to time (ANOVA(p<.05)). However, no significant mode of treatment, or mode of treatment/assessment time interaction was present. Decreases in range of motion and flexion strength correspond with increases in perceived soreness. The nonsignificant mode of treatment/assessment time interaction suggests that the use of ice massage, ice massage with exercise, or exercise alone is not effective in significantly reducing the symptoms of delayed onset muscle soreness. In fact, though not statistically significant, the pattern of the data suggested the use of ice in the treatment of DOMS may be contraindicated. Further investigation is recommended.  相似文献   
4.
The nature of deposits present in hypoplastic defects of fluorotic enamel of wild boar teeth was studied by light microscopy and scanning electron microscopy. The fluorotic enamel showed different developmental abnormalities, denoting a severe disturbance of ameloblast function during the secretory stage of amelogenesis. These abnormalities included the occurrence of grossly accentuated incremental lines with associated zones of aprismatic enamel and the presence of different forms of hypoplastic defects. Two types of deposits were present on the hypoplastic enamel: cellular cementum and posteruptively acquired, presumably partially mineralized dental plaque. Coronal cementum is not normally formed in pig teeth. Presence of this tissue in fluorotic teeth of wild boars is seen as indicative of a premature disintegration of the enamel epithelium prior to the completion of amelogenesis. This was supposed to have resulted in a contact of mesenchymal cells of the dental follicle with the surface of the immature enamel and, in consequence, in a differentiation of these cells into cementoblasts. To our knowledge, this is the first study reporting the formation of coronal cementum as part of the spectrum of pathological changes in fluorotic teeth in a species whose tooth crowns are normally free of cementum.  相似文献   
5.
VLBI observations of the extremely gamma-bright blazar PKS 0528+134 at 8, 22, 43, and 86 GHz reveal a strongly bent one-sided-core jet structure with at least three moving and two apparently stationary jet components. At the highest observing frequencies the brightest and most compact jet component (the VLBI core) is unresolved with an upper limit to its size of approximately 50 microarcsec corresponding to approximately 0.2 parsec [H0 = 100 km.s-1.Mpc-1 (megaparsec-1), q0 = 0.5, where H0 is Hubble constant and q0 is the deceleration parameter]. Two 86-GHz VLBI observations performed in 1993.3 and 1994.0 reveal a new jet component emerging with superluminal speed from the core. Linear back-extrapolation of its motion yields strong evidence that the ejection of this component is related to an outburst in the millimeter regime and a preceding intense flare of the gamma-flux density observed in early 1993. This and the radio/optical "light curves" and VLBI data for two other sources (S5 0836+710 and 3C 454.3) suggest that the observed gamma-radiation might be Doppler-boosted and perhaps is closely related to the physical processes acting near the "base" of the highly relativistic jets observed in quasars.  相似文献   
6.
For the treatment of patients with advanced HER2-negative hormone receptor-positive breast cancer, several substances have been introduced into practice in recent years. In addition, other drugs are under development. A number of studies have been published over the past year which have shown either an advantage for progression-free survival or for overall survival. This review summarizes the latest results, which have been published at current congresses or in specialist journals, and classifies them in the clinical treatment context. In particular, the importance of therapy with CDK4/6 inhibitors – trastuzumab deruxtecan, sacituzumab govitecan and capivasertib – is discussed. For trastuzumab deruxtecan, an overall survival benefit in HER2-negative breast cancer with low HER2 expression (HER2-low expression) was reported in the Destiny-Breast-04 study. Similarly, there was an overall survival benefit in the FAKTION study with capivasertib. The lack of overall survival benefit for palbociclib in the first line of therapy raises the question of clinical classification.Key words: advanced breast cancer, chemotherapy, endocrine therapy, antibody drug conjugates  相似文献   
7.
Two children in whom idiopathic hypernasality was diagnosed were referred for investigation of velopharyngeal function. Multiview videofluoroscopic assessments showed the tonsils prolapsing posteriorly during speech, preventing the palate from fully approximating the posterior pharyngeal wall. Tonsillectomy was recommended. Postoperative evaluations found that the hypernasal resonance was eliminated in both children.  相似文献   
8.
The treatment of patients with early stage breast cancer has changed in recent years due to the introduction of pembrolizumab, olaparib, and abemaciclib. These and other drugs with the same class of active ingredient are currently in trial for various indications. This review article summarizes the latest results that have either been presented at major conferences such as the ESMO 2022 or published recently in international journals. This includes reports on newly discovered breast cancer genes, atezolizumab in neoadjuvant therapy in HER2-positive patients, long-term data from the APHINITY study, and on how preoperative peritumoral application of local anesthetics can influence the prognosis. We also present solid data on dynamic Ki-67 from the ADAPT studies.Key words: breast cancer, surgery, chemotherapy, therapy standard  相似文献   
9.
Nodular fasciitis is a lesion found in the subcutaneous fascia that micoscopically presents as a benign proliferation of fibroblasts and myofibroblasts, which may be mistaken for a sarcoma due to clinically rapid growth. Diagnosis is by histopathology and of the immunohistochemical profile. We describe a case of nodular fasciitis in the oral cavity that demonstrated partial spontaneous regression. The patient was a 32-year-old man with a buccal mucosal mass, which had grown rapidly for 45 days. On microscopic examination, the lesion displayed a well-delineated but not encapsulated proliferation of spindle cells, with a nodular growth pattern. Immunohistochemical analysis showed positivity of the spindle cells for the antibodies against smooth muscle actin and muscle-specific actin (HHF-35). Treatment of such lesions typically involves complete conservative excision, but the lesion may regress eventually in the absence of definitive treatment.  相似文献   
10.
The neonatal line (NNL) is a distinct incremental marking in the dental enamel, especially in deciduous teeth. In the course of tooth development the NNL represents the position of the enamel-forming front at the time of birth in all the teeth already forming hard tissues at this time. If birth is survived for a certain period of time, deposition of new enamel can be detected outside the NNL. The material properties of teeth, the lack of remodeling, and the known chronology of incremental structures in enamel make teeth an important source of information of vital data in retrospective analyses. Counting enamel incremental markings with circadian periodicity in postnatal enamel enables the determination of the duration of the postnatal lifespan. The lack of an NNL indicates death in utero. In this respect an important contribution can be made by structural analyses of teeth to the investigation of decomposed remains of fetuses and young infants.  相似文献   
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