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排序方式: 共有1674条查询结果,搜索用时 15 毫秒
71.
Anatomical radical retropubic prostatectomy: 'curtain dissection' of the neurovascular bundle 总被引:5,自引:0,他引:5
OBJECTIVE: To investigate the topographical relationship of the cavernosal nerves (CNs) to seminal vesicles, prostate, rhabdosphincter and urethra during the development of the prostate, and to use the resulting morphological data to modify the surgical technique of nerve-sparing radical prostatectomy. MATERIALS AND METHODS: The study included 29 male fetuses (gestational age 9-37 weeks) and eight adult specimens assessed anatomically and histologically. Using the plastination technique and anatomical dissection, the course of the CNs was investigated in all specimens. Based on these morphological results, the technique of dissecting the CNs during nerve-sparing radical retropubic prostatectomy was modified. RESULTS: During early fetal development the fibres of the CNs enclose the prostatic and membranous urethra dorsally and laterally. During the growth of the prostate, the CNs running along the prostate become displaced further anteriorly and spread, thus forming a concave shape (like a 'curtain') of the neurovascular bundles (NVB). Therefore, dissection of the NVB has to start anteriorly to preserve all the nerve fibres that are spread along the surface of the lateral lobes of the prostate. CONCLUSIONS: From these anatomical findings we propose a modified 'curtain dissection' to improve preservation of the CNs running in the NVB, in which the incision of the periprostatic fascia and dissection of the NVB is far more anterior than previously described. 相似文献
72.
A variant form of maple syrup urine disease (grade II) in a twelve year old boy is reported. The clinical picture was characterized by seizure-like episodes of confusion and intermittent ataxia. The diagnosis was made by showing an increased excretion of branched-chain alpha-hydroxy acids as well as evaluated plasma concentrations of the branched-chain aminoacids and alpha-ketoacids. There was a decrease of leucine degradation in cultured fibroblasts to 5 to 6% of normal. The treatment with thiamine-hydrochlorid remained without any clinical or biochemical effect in our patient. Further neurologic symptoms during acute episodes of vomiting could be avoided by dietary protein restriction and early parenteral glucose supplementation. 相似文献
73.
Information concerning the anatomy of the physiological foramen is limited. The aim of this study was to investigate the distance between the physiological and anatomical apex, accessory foramina frequency, and the shape and diameter of the physiological foramen in maxillary and mandibular molars. The apical anatomy of 523 maxillary and 574 mandibular molars from an Egyptian population was investigated by means of a computer-aided stereomicroscope (40 x magnification). The following results were obtained: 相似文献
74.
PURPOSE: To determine the shear bond strength (SBS) of different established (Resulcin Aqua Prime & Monobond N: RA, Prompt L-Pop III: PLP) and experimental (AC-Bond: AC, AC-Bond + Desensitizer: ACD) self-etching adhesives in comparison to fourth (Optibond FL: FL) and fifth generation (Excite: EX, Gluma Comfort Bond: CB) adhesives. MATERIALS AND METHODS: All adhesives were applied on flat enamel and dentin surfaces and light cured following manufacturers' directions. Tetric Ceram A2 composite cylinders 3.5 mm in diameter and 2.0 mm in height were sheared off (1 mm/min) after thermocycling (5 to 55 degrees C, 5000x). The t-test (5% level, Bonferroni-correction) was used for statistical analysis. RESULTS: SBS in enamel: RA: 27.0+/-5.8 MPa, PLP: 15.9+/-3.4 MPa, AC: 28.1+/-4.4 MPa, ACD: 22.2+/-4.1 MPa, FL: 33.2+/-3.2 MPa, EX: 30.5+/-5.1 MPa, CB: 30.1+/-3.7 MPa. SBS in dentin: RA: 25.8+/-5.7 MPa, PLP: 20.7+/-2.9 MPa, AC: 27.0+/-4.5 MPa, ACD: 20.7+/-3.7 MPa, FL: 34.4+/-3.8 MPa, EX: 30.0+/-4.6 MPa, CB: 27.9+/-2.6 MPa. FL resulted in significantly (p < 0.002) higher SBS in enamel and dentin than RA, AC, ACD, and PLP, and in higher SBS to dentin than CB. In enamel and dentin, RA performed significantly superior to PLP, but was not different from AC and ACD. EX and CB were both on the same level of significance as AC and RA, but showed superior results to ACD and PLP (enamel and dentin). PLP resulted in significantly lower SBS values in enamel and dentin than all the other materials investigated, except ACD in dentin, to which it was equivalent. CONCLUSION: Resulcin Aqua Prime & Monobond N and AC-Bond were not significantly different than established 5th generation products. AC-Bond + Desensitizer and Prompt L-Pop have significantly different SBS from established 4th and 5th generation products. Future studies are required to investigate marginal integrity to determine if self-etching adhesives are an adequate alternative to one- and multi-bottle systems. 相似文献
75.
Sotlar K Horny HP Simonitsch I Krokowski M Aichberger KJ Mayerhofer M Printz D Fritsch G Valent P 《The American journal of surgical pathology》2004,28(10):1319-1325
The diagnosis of systemic mastocytosis (SM) is based primarily on the histologic and immunohistochemical evaluation of a bone marrow trephine biopsy specimen. Although mast cell (MC) specific antigens like tryptase and chymase are detectable in routinely processed tissue, no immunohistochemical markers that can be used to discriminate between normal and neoplastic MCs are yet available. We have investigated the diagnostic value of an antibody against CD25 for the immunohistochemical detection of MCs in bone marrow sections in 73 patients with SM and 75 control cases (reactive marrow, n = 54; myelogenous neoplasms, n = 21) and correlated the results with the presence of c-kit mutations. While MCs in almost all patients with SM (72 of 73) expressed CD25, none of the control samples contained CD25-positive MCs. Irrespective of the SM subtype, most of neoplastic MCs expressed CD25. In 3 patients with advanced MC disease, pure populations of neoplastic MCs were obtained and found to express CD25 mRNA by RT-PCR analysis. In addition, all patients with CD25-positive MCs contained c-kit mutations, while all control cases exhibited wild type c-kit. CD25 therefore appears to be a reliable immunohistochemical marker for the discrimination of neoplastic from normal/reactive MCs, with potential as a diagnostic tool in SM. 相似文献
76.
77.
Antitumor activity of a kinesin inhibitor 总被引:7,自引:0,他引:7
Sakowicz R Finer JT Beraud C Crompton A Lewis E Fritsch A Lee Y Mak J Moody R Turincio R Chabala JC Gonzales P Roth S Weitman S Wood KW 《Cancer research》2004,64(9):3276-3280
Several members of the kinesin family of microtubule motor proteins play essential roles in mitotic spindle function and are potential targets for the discovery of novel antimitotic cancer therapies. KSP, also known as HsEg5, is a kinesin that plays an essential role in formation of a bipolar mitotic spindle and is required for cell cycle progression through mitosis. We identified a potent inhibitor of KSP, CK0106023, which causes mitotic arrest and growth inhibition in several human tumor cell lines. Here we show that CK0106023 is an allosteric inhibitor of KSP motor domain ATPase with a Ki of 12 nM. Among five kinesins tested, CK0106023 was specific for KSP. In tumor-bearing mice, CK0106023 exhibited antitumor activity comparable to or exceeding that of paclitaxel and caused the formation of monopolar mitotic figures identical to those produced in cultured cells. KSP was most abundant in proliferating human tissues and was absent from cultured postmitotic neurons. These findings are the first to demonstrate the feasibility of targeting mitotic kinesins for the treatment of cancer. 相似文献
78.
Fritsch MH Wynne MK Diefendorf AO 《International journal of pediatric otorhinolaryngology》2002,66(1):29-36
OBJECTIVE: Otoacoustic emissions (OAEs) are low-level acoustic signals which emanate from the cochlea and can be recorded in the ear canal. The two types of OAEs are spontaneous and evoked otoacoustic emissions. METHODS: In this retrospective study, transient-evoked otoacoustic emissions (TEOAEs) were measured in 385 ears from 204 children with normal hearing and tympanostomy tubes. RESULTS: The results indicate that, when using the Quick Screen option on the Oto-Dynamics ILO88 Otoacoustic Emission Analyzer, postoperative TEOAEs were present at all measured frequencies in 81% of the ears. The remaining 19% of ears showed the absence of an observable emission at one or more of the measured response frequencies. The overwhelming factor contributing to an absent emission was insufficient stimulus energy at 4 kHz. The use of T-type tympanostomy tubes also appeared to decrease the probabilities obtaining normal TEOAEs in ears with normal peripheral auditory function. The use of grommet-type tympanostomy tubes, the type of middle ear effusion, the age and gender of the child, and the physical volume of the ear canal as measured by tympanometry with the tympanostomy tube patent and in place had negligible effects on the measurement of TEOAEs. CONCLUSIONS: Clinicians must be cautious when interpreting click-evoked TEAOEs if the patient has a T-tube in place and may need to modify this testing to rule out high-frequency hearing loss when using TEOAEs with these patients. For those patients who have tympanostomy tubes and fail to meet the "pass criteria" for TEOAEs at 4 kHz in the Quick Screen option, TEOAE should be repeated either in the Diagnostic mode or by using a 4 kHz tone-burst stimulus centered at 4 kHz to recover the loss of energy in this region due to the high-frequency roll-off of the stimuli used in the Quick Screen option. 相似文献
79.
Fritsch MH 《Otolaryngologic clinics of North America》2002,35(2):425-444
The large ablations needed to remove some lateral skull base pathologic conditions remain a challenge to the reconstructive surgeon. Major shortcomings abound despite significant development of surgical techniques and advances in the understanding of healing. The tremendous advances of the past 30 years with the dawn of major tissue transfer techniques, new biomaterials, and the use of surgical teams with enormous combined clinical knowledge bases have catapulted surgical reconstruction efforts. Progress has been tempered by the realization that normal tissue functions are still incompletely rebuilt. As work on tissue culture, genomic understanding, biomechanics, blood oxygenation substituted, and other research fronts progress and converge, newer and better ways of addressing lateral skull base reconstruction will arise. 相似文献
80.
Fritsch C Swietlicki EA Lefebvre O Kedinger M Iordanov H Levin MS Rubin DC 《The Journal of clinical investigation》2002,110(11):1629-1641
The formation of the crypt-villus axis during gut ontogeny requires continued reciprocal interactions between the endoderm and mesenchyme. Epimorphin/syntaxin 2 (epimorphin) is a mesenchymal protein expressed in the fetal gastrointestinal tract during villus morphogenesis. To elucidate its role in gut ontogeny, the epimorphin cDNA was transfected, in sense and antisense orientations, into a rat intestinal myofibroblast cell line, MIC 216. To determine the effects of epimorphin on the epithelium, myofibroblasts were cocultured with the Caco2 cell line. Caco2 cells spread in a simple monolayer over antisense-transfected cells lacking epimorphin. In contrast, sense-transfected myofibroblasts induced Caco2 cells to form compact, round clusters with small lumens. These morphologic differences were preserved in Transwell cocultures in which cell-cell contact was prevented, suggesting that epimorphin's effects were mediated by secreted factor(s). To determine the effects of epimorphin on crypt-villus axis formation in an in vivo model, rat gut endoderm was combined with epimorphin-transfected myofibroblasts and implanted into the chick intracoelomic cavity. The grafts in which epimorphin was overexpressed revealed multiple well-formed villi with crypt-like units, whereas those in which epimorphin expression was inhibited developed into round cystic structures without crypts or villi. Of several potential secreted morphogens, only the expression of bone morphogenetic protein 4 (Bmp4) was increased in the epimorphin-transfected cells. Incubation with noggin partially blocked the transfected myofibroblasts' effects on Caco2 colony morphology. These results indicate that mesenchymal epimorphin has profound effects on crypt-villus morphogenesis, mediated in part by secreted factor(s) including the Bmp's. 相似文献