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31.
Journal of Assisted Reproduction and Genetics - Tetrasomy 9p (ORPHA: 3310) (i(9p)) is a rare chromosomal imbalance. It is characterized by the presence of a supernumerary chromosome incorporating...  相似文献   
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33.
In this review, classical data on the early steps in human odontogenesis are summarized and updated with specific insights into the development of the upper and lower embryonic jaws to help in understanding some oral pathologies. The initial step of human odontogenesis is classically characterized by two parallel horseshoe‐shaped epithelial laminae. These originate from the oral epithelium and an ingrowth into the jaw mesenchyme: the internal dental lamina gives rise to deciduous tooth primordia, while the external vestibular lamina represents the developmental base of the oral vestibule. However, a more complex situation was revealed by recent studies combining analyses of the dental and adjacent oral epithelia on histological sections and computer‐aided three‐dimensional (3D) reconstructions during the 2nd month of human embryonic development. The dental epithelium forms a mound, where swellings appear later, corresponding to the individual primordia of deciduous teeth. External to the developing deciduous dentition, the 3D reconstructions do not show any continuous vestibular lamina but instead a complex of discontinuous epithelial bulges and ridges. The patterns of these epithelial structures and their relationship to the dental epithelium differ not only between the upper and lower jaws but also between the lip and cheek segments in each jaw. Knowledge of early odontogenesis may help in understanding some oral pathologies. For example, the human lateral incisor has a dual origin: it arises in the area of fusion between the medial nasal and maxillary facial processes and involves material from these two regions. Such a dual origin at the site of fusion of facial processes represents a predisposition to developmental vulnerability for the upper lateral incisor, resulting in its frequent anomalies (absence, hypoplasia, duplication), especially in patients with a cleft lip and/or jaw. Other pathologies, such as a minute supernumerary tooth, desmoplastic ameloblastoma or extraosseous odontogenic cysts are located external to the upper or lower dentition, and might be derived from structures that transiently appear during early development of the oral vestibule in humans.  相似文献   
34.
Cytogenetic studies in lymphomas classically require fresh or frozen tissue, whereas in many instances only paraffin-embedded biopsies are available. We applied an interphase FISH assay on nuclei extracted from thick paraffin sections to determine accuracy of molecular cytogenetics in such samples. Twenty-three lymphoma samples and 4 reactive lymph nodes were tested with various commercially available DNA probes, and hybridization patterns were compared with those obtained on frozen nuclei counterparts. Successful hybridization with all probes tested was observed for 23/27 (85%) paraffin-embedded tissues and for all (100%) frozen samples, and cut-off levels defining positivity were superimposable for both situations. Chromosome changes were detected in the same way, without any false-positive or false-negative cases. Hybridization signals observed on dewaxed samples were either those classically expected to define the relevant chromosome change or were atypical: all atypical changes could be demonstrated also into nuclei from the frozen counterpart. Moreover, all typical and atypical chromosome changes observed on frozen nuclei were also detected in paraffin-embedded tissues. Our study shows that our interphase FISH assay performed on paraffin-embedded samples is a valuable alternate to conventional methods to ascertain diagnosis of lymphomas as to include patients into therapeutic trials.  相似文献   
35.
M-mode echocardiography reveals an abrupt change between early and late left ventricular posterior wall kinetics during relaxation. No attempt has been previously made to relate this wall kinetic change and transmitral flow rate. In 25 normal subjects, 14 patients with dilated cardiomyopathy (Group 1) and 17 patients with hypertrophic cardiomyopathy (Group 2), M-mode echocardiographic studies were performed on the posterior wall and mitral valve. Transient values of mitral orifice area were calculated and transmitral flow velocities were recorded: area and velocity data yielded transmitral flow rates. Time intervals were determined from mitral opening to peak early area, velocity and flow rate and to posterior wall slope change. An additional group included five patients with a mitral prosthesis. The posterior wall slope change was present when part of the myocardial structures were almost akinetic or when mitral chordae tendineae were absent; slope change appeared as a regional phenomenon in the free wall. In the normal subjects, close values were found for the four time intervals. In the patients with dilated and hypertrophic cardiomyopathy, peak early velocity (95.7 +/- 16.7 and 146.2 +/- 31.4 ms, respectively), peak flow rate (84.7 +/- 18.2 and 137.4 +/- 29.5 ms) and time to slope change (91.4 +/- 18.6 and 133.6 +/- 32.7 ms) were significantly delayed (p less than 0.001) in comparison with peak area (56.6 +/- 9.5 and 84.3 +/- 22.5 ms). Slope change does not indicate the end of the early filling phase but, rather, its transition from acceleration to deceleration. Time to peak velocity or time to peak filling rate must be considered in a relaxation analysis.  相似文献   
36.
Endovascular repair of the thoracic aorta has been adopted as the first-line therapy for much pathology. Initial results from the early-generation endografts have highlighted the potential of this technique. Newer-generation endografts have now been introduced into clinical practice and careful assessment of their performance should be mandatory. This study describes the initial experience with the Valiant endograft and makes comparisons with similar series documenting previous-generation endografts. Data were retrospectively collected on 180 patients treated with the Valiant endograft at seven European centers between March 2005 and October 2006. The patient cohort consisted of 66 patients with thoracic aneurysms, 22 with thoracoabdominal aneurysms, 19 with an acute aortic syndrome, 52 with aneurysmal degeneration of a chronic dissection, and 21 patients with traumatic aortic transection. The overall 30-day mortality for the series was 7.2%, with a stroke rate of 3.8% and a paraplegia rate of 3.3%. Subgroup analysis demonstrated that mortality differed significantly between different indications; thoracic aneurysms (6.1%), thoracoabdominal aneurysms (27.3%), acute aortic syndrome (10.5%), chronic dissections (1.9%), and acute transections (0%). Adjunctive surgical procedures were required in 63 patients, and 51% of patients had grafts deployed proximal to the left subclavian artery. Comparison with a series of earlier-generation grafts demonstrated a significant increase in complexity of procedure as assessed by graft implantation site, number of grafts and patient comorbidity. The data demonstrate acceptable results for a new-generation endograft in series of patients with diverse thoracic aortic pathology. Comparison of clinical outcomes between different endografts poses considerable challenges due to differing case complexity.  相似文献   
37.
The authors emphasize an unusual complication of venous angiomas in the brain: venous infarction. The patient in this case is a 32-year-old man who presented with a clinical history of headache followed by a worsening of his neurological status. Neuroimaging studies demonstrated a brain infarct in the posterior fossa, which was related to thrombosis of the draining vein of a cerebral venous angioma. A conservative treatment approach without anticoagulation therapy was followed and the patient completely recovered. Nonhemorragic venous infarction caused by thrombosis of a venous angioma is exceptional and only nine previous cases have been reported in the literature.  相似文献   
38.
OBJECTIVE: To evaluate the oncological outcome and functional results of prostate-sparing cystectomy (PSC), proposed for treating bladder cancer, used since 1999 in our institution in an attempt to preserve male sexuality and to increase continence after cystectomy. PATIENTS AND METHODS: Between January 1999 and December 2001, 111 men were candidates for cystectomy; 42 were selected for a prostatic capsule- and seminal-sparing cystectomy with orthotopic urinary diversion. All patients had clinically organ-confined tumours (clinical stage 相似文献   
39.
Background: The innervation of skin and oral mucosa plays a major physiological role in exteroception. This innervation is also clinically relevant as sensory changes occur after neurosurgical procedures. Purpose: The goal of this study was to compare the perception of mechanical stimuli applied to the buccal mucosa in the vicinity of osseointegrated oral implants with that in the controlateral dentate side. The role of the previously reported increased innervation in the peri‐implant soft tissues in the oral sensorimotor function was thus examined. Materials and Methods: Seventeen subjects with 20 implants were tested. Directional cutaneous kinaesthesia (DCK) and graphesthesia (G) were performed on the buccal side of the alveolar mucosa before and at planned intervals after implant placement. The observation was pursued until 6 months after the prosthetic rehabilitation. In each subject, the contralateral mucosa served as a control to the implant sites. Average percentages of correct responses in a four‐choice task for DCK and a three‐choice task for G were calculated. Results: Despite an intersubject variation in both the DCK and G, high intraindividual correlations were found (p < .005). The implant sites showed a significant difference toward the control sites at the four interval test for both tests. For DCK and G, the average of correct responses decreased after abutment connection (i.e., after the implant uncovering surgery) to increase afterwards to reach a level close to, but still lower than, the control sites 3 to 6 months after the prosthetic rehabilitation. Conclusion: The DCK and G are simple but reliable sensory tests that can be easily applied in the oral region. This prospective study indicates that tooth loss reduces tactile function compared with implant‐supported prostheses. The peri‐implant soft tissues could be partially involved in the osseoperception function.  相似文献   
40.
Thoracic splenosis is the autotransplantation of splenic tissue in the left thoracic cavity as a result of a splenic injury. This rare pathology is usually asymptomatic and may be discovered on incidental imaging, but the diagnosis often requires invasive procedures such as surgery in order to eliminate a neoplasic origin. We report a rare symptomatic case of a 39-year-old man presenting with chest pain and multiple nodules revealed on a computed tomography scan. The patient underwent a surgical exploration and the pathological studies concluded to a thoracic splenosis. Indeed, the previous medical history of the patient revealed a left thoraco-abdominal traumatism during childhood. The aim of this paper is to emphasize that the diagnosis can now be performed using only imaging techniques such as technetium-99 sulfur colloid or labelled heat-denatured red blood cell scintigraphy to avoid unnecessary invasive procedures including thoracotomy.  相似文献   
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