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91.
The forces to produce fractures of the os calcis are combined compression and shear under a cranio-caudal impulse of 10-40 kN and a short time of stroke about 10-40 ms. The main patterns in biomechanics of calcaneal fractures are the time of stroke and the geometrical position of the foot in the moment of impact. Furthermore individual structural changes of the calcaneal cancellous bone, age, diseases as Diabetes mellitus and vascular obliterations are to be respected. Operative treatment of these fractures needs an understanding of the pathomechanism of the intracalcaneal shear-tension-forces. With plantarflexion of the foot combined with vertical forces within 40 ms to the anterior talocalcanear facette impact-fractures of the anterior part can be expected. These forces develop a posterior directed shear tension parallel to the axis of the os calcis, dividing the bone horizontally in two parts (Typ A, 44-56%), well-known as tongue-type fracture. Compression of the posterior talo-calcaneal joint leads to an impact of this structure producing the joint depression type within about 30 ms in dorsoflexion of the foot (Type B, 42%) together with sagittal shear fractures. High-energy forces are supposed to produce the so-called primary fractures of the sustentacular process in about 10 ms in a supinated position of the foot (Type C, 2-10%); these fractures represent in cases of dislocation an indication for open reduction and internal fixation. In our own experience with 45 cases in 35 patients using the lateral or/and medial approach no infection happened. Palmer's lateral approach was preferred. 相似文献
92.
93.
Raj P. Kapur Ian Neilson Robert M.W. Hofstra Lynda W. Holloway Ron C. Michaelis Kathleen A. Leppig 《American journal of medical genetics. Part A》2002,108(1):51-56
Congenital hydrocephalus associated with aqueductal stenosis and/or agenesis of the corpus callosum has been described in newborn males with mutations in L1CAM, a gene that encodes a neural cell adhesion molecule. These males usually have severe mental retardation and may have spastic paraplegia and adducted thumbs. In contrast, Hirschsprung disease, or absence of ganglion cells in the distal gut, has rarely been described in such individuals. We report a male infant who had severe hydrocephalus identified in the prenatal period with evidence of aqueductal stenosis and adducted thumbs at birth. He developed chronic constipation, and rectal biopsy confirmed the diagnosis of Hirschsprung disease. Molecular testing of the L1CAM gene revealed a G2254A mutation, resulting in a V752M amino acid substitution. A common polymorphism in RET, but no mutation, was identified. Our patient represents the third example of coincident hydrocephalus and Hirschsprung disease in an individual with an identified L1CAM mutation. We hypothesize that L1CAM‐mediated cell adhesion may be important for the ability of ganglion cell precursors to populate the gut, and that L1CAM may modify the effects of a Hirschsprung disease–associated gene to cause intestinal aganglionosis. © 2002 Wiley‐Liss, Inc. 相似文献
94.
This article describes how genetic components of disease susceptibility can be evaluated in case-control studies, where cases and controls are sampled independently from the population at large. Subjects are assumed unrelated, in contrast to studies of familial aggregation and linkage. The logistic model can be used to test collapsibility over phenotypes or genotypes, and to estimate interactions between environmental and genetic factors. Such interactions provide an example of a context where non-hierarchical models make sense biologically. Also, if the exposure and genetic categories occur independently and the disease is rare, then analyses based only on cases are valid, and offer better precision for estimating gene-environment interactions than those based on the full data. 相似文献
95.
The confrontation with one's body appearance as recorded on a video might have an impact on the body experience of anorexia nervosa patients. Such a video confrontation was applied to a group of 12 anorectic females. After the procedure, these patients rated their actual body (using Osgood's Semantic Differential) as thinner and more active; the control group of 12 female anorectics did not change their evaluations. The patients' evaluation of their ideal body image was not influenced. 相似文献
96.
Walter Daghino MD Luigi Milano MD Sergio Ronco MD Giorgio Ronco MD Angelo Dettoni MD Massimo Cartesegna MD 《The Journal of foot and ankle surgery》2003,42(3):155-160
This article is a retrospective study comparing the efficacy of Regnauld arthroplasty to first ray osteotomies for the treatment of hallux valgus. One hundred consecutive cases of Regnauld arthroplasties were compared with 100 consecutive first ray osteotomies. One hundred fourty-one patients were available for follow-up, and based on clinical/radiographic examinations, 72 were treated with the osteotomy protocol (group A) and 69 with Regnauld arthroplasty (group B). Age at surgery, clinical symptoms, and preoperative radiologic findings were similar for the 2 groups; there was a preponderance of female patients (90%). The average follow-up was 49 months in group A and 51 months in group B. Clinical evaluation showed in the osteotomy group a more stable correction (79% v 49%), greater pain reduction (measured in a visual analog scale from 0 = pain free to 10 = deep intolerable pain), increased residual articular excursion of the first metatarsophalangeal joint (27 degrees of active dorsiflexion from neutral position v 8 degrees ), and less presence of central metatarsalgia (15% v 34%) (P <.05). The radiographic evaluation expressed more stable correction values in group A for the following parameters: joint preservation, sesamoid position, intermetatarsal angle (7 degrees v 12 degrees ), abduction angle of the hallux (14 degrees v 20 degrees ), and proximal articular set angle (8 degrees v 18 degrees ) (P <.05). 相似文献
97.
98.
Colorectal tumor screening in women with a past history of breast, uterine, or ovarian malignancies 总被引:2,自引:0,他引:2
Epidemiologic studies have shown that women who have successfully recovered from breast, uterine, or ovarian cancer have about twice the expected risk of developing colorectal cancer. These high-risk women were entered, therefore, into a large bowel screening program based on fecal occult blood detection, flexible sigmoidoscopy, and colonoscopy, when appropriate. The study group consisted of 183 women and the results were compared with 252 comparison subjects of similar age and ethnic origin. Neoplastic lesions, adenomatous polyps, or cancer were 2.5 times more frequent in the study group. However, for the largest group, women with a past history of breast cancer, the relative risk, adjusted for a family history of gastrointestinal cancer, was 3.0 (P = 0.03). This pilot study confirms the value of continuing to screen these patients, especially those with a positive family history of gastrointestinal malignancies. However, for psychological and administrative reasons, it may be better that their colon screening be integrated into a combined colon, breast, and gynecologic tumor follow-up, and not be part of a separate service. 相似文献
99.
What Is Sufficient Evidence for the Reliability and Validity of Patient-Reported Outcome Measures? 总被引:1,自引:0,他引:1
100.
Univ.-Prof. Dr. P. Walter 《Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft》2005,102(10):931-932
Ohne Zusammenfassung 相似文献