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71.
BACKGROUND: Tracheotomies are routinely performed for severely ill and elderly patients with respiratory failure. This intervention is questioned, given the poor survival rate in this group. Outcomes analysis is performed after tracheotomy. METHODS: This is a retrospective study of 78 elderly patients, who received tracheotomies for respiratory failure. Pretracheotomy data (age, length of oral intubation, and DNR status) were collected. Outcomes analyzed during the same admission as the tracheotomy included death versus discharge, ventilator dependence, vocal function, route of feeding, decannulation, and ICU discharge disposition. RESULTS: The mean age was 77.6 +/- 11 years (median, 79 years) and patients were intubated for 16.7 +/- 9 days. Forty-two percent (n = 33) obtained DNR orders after tracheotomy, and 8% (n = 6) before tracheotomy. Seventy-one percent of patients (n = 55) had gastrostomy tubes placed. Fifty-six percent of patients (n = 44) died after tracheotomy; median time from tracheotomy to death was 31 days. After tracheotomy, 53 % (n = 41) remained at least partially ventilator dependent, 18 % (n = 14) regained consistent vocal function, and 13 % (n = 10) were decannulated. For those who died, 27 % (n = 12) died without leaving the ICU. CONCLUSION: These data demonstrate that a large proportion of elderly, severely ill patients with respiratory failure suffer poor outcomes after tracheotomy. More stringent criteria are necessary for performing the tracheotomy in this patient population.  相似文献   
72.
In approximately 15% of children with atraumatic subarachnoid hemorrhage (SAH), the cause of the hemorrhage cannot be determined despite detailed imaging studies. Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PNSH) is well recognized as a distinct type of SAH in the adult population and may account for up to two thirds of these SAHs of unknown cause. PNSH in the pediatric population, however, is not well recognized. In this report, we confirm the existence of PNSH in the pediatric population by describing a 4-year-old boy who presented with acute SAH in the perimesencephalic cisterns and subsequently had two negative angiograms with a benign clinical course. Recognition of PNSH in the pediatric population is important, especially in view of its benign nature.  相似文献   
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PURPOSE: The mechanism of human erection requires the coordination of an intact neuronal system that includes the cavernous, perineal, and dorsal nerves of the penis. We defined the communication of these 3 nerves that travel under the pubic arch using specific neuronal immunohistochemical staining and 3-dimensional reconstruction imaging technique. MATERIALS AND METHODS: A total of 18 normal human fetal penile specimens at 17.5 to 32 weeks of gestation were studied by immunohistochemical techniques. Serial sections were stained with antibodies raised against the neuronal markers S-100, and neuronal nitric oxide synthase (nNOS), vesicular acetylcholine transporter (VAChT), calcitonin gene-related peptide and substance P. RESULTS: The continuation of the dorsal neurovascular bundle of the prostate was documented under the pubic arch. Two distinct nerve bundles were identified superior to the urethra and medial to the origin of the crural bodies. Nerve bundles were observed to join the corporeal bodies at the penile hilum. Proximal to the penile hilum the dorsal nerves stained only for S-100 and VAChT. From the junction of the crural bodies at the hilum to the glans penis dorsal nerve fibers stained positive for S-100, VAChT and nNOS. Calcitonin gene-related peptide and substance P demonstrated positive staining at the distal nerves, particularly at the glans. In contrast, the whole course of the cavernous nerve stained for S-100 and nNOS. Under the pubic arch at the penile hilum the cavernous nerves were found to convey nNOS positive branches to the dorsal nerve to transform its immunoreactivity to nNOS positive. Proximal nNOS negative perineal nerves were shown to stain positive for nNOS distal on the penis. Interaction between nNOS positive dorsal nerve branches and perineal nerves was at the cavernous-spongiosal junction, where the bulbospongiosus muscle terminates. CONCLUSIONS: At penile hilum, where the corporeal bodies start to separate, the cavernous nerve sends nNOS positive fibers to join the dorsal nerve of the penis, thereby, changing the functional characteristics of the distal penile dorsal nerve. Similarly the nNOS negative, ventrally located perineal nerve originating from the pudendal nerve becomes nNOS reactive at the cavernous-spongiosal junction. These 2 examples of redundant neuronal wiring in the penis may impact erectile function, especially during reconstructive surgery.  相似文献   
74.
Homology modeling was used to build 3D models of the N-methyl-d-aspartate (NMDA) receptor glycine binding site on the basis of an X-ray structure of the water-soluble AMPA-sensitive receptor. The docking of agonists and antagonists to these models was used to reveal binding modes of ligands and to explain known structure-activity relationships. Two types of quantitative models, 3D-QSAR/CoMFA and a regression model based on docking energies, were built for antagonists (derivatives of 4-hydroxy-2-quinolone, quinoxaline-2,3-dione, and related compounds). The CoMFA steric and electrostatic maps were superimposed on the homology-based model, and a close correspondence was marked. The derived computational models have permitted the evaluation of the structural features crucial for high glycine binding site affinity and are important for the design of new ligands.  相似文献   
75.
OBJECTIVES: To describe the effects of exogenous oestrogens and androgens on urethral formation in the mouse, as the development of the mouse and human urethra have significant similarities, and understanding normal male urethral development may help to identify the causes of abnormal development, e.g. hypospadias. MATERIALS AND METHODS: Timed-pregnant C57/6 mice were exposed to synthetic oestrogens and androgens. The morphology of the genital tubercles was examined histologically and with three-dimensional computer reconstruction. Specific attention was focused on the developing urethral seam. RESULTS: Microscopic serial analysis confirmed the presence of an arrest in seam formation in about half of oestrogen-treated male fetuses. In contrast, there was acceleration of urethral fold fusion and a longer urethral tube in those treated with androgens. Oestrogen-treated fetuses had a thin periurethral spongiosa, in contrast to androgen-treated fetuses which developed a thicker periurethral spongiosa. The effect of oestrogens on seam area formation did not depend on the dose, but in contrast, in the androgen-treated fetuses it was. CONCLUSION: Oestrogens and androgens have a direct effect on the fusion of the urethral fold that leads to seam formation. Normal urethral development depends on the delicate balance of these complementary hormones.  相似文献   
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77.
The demand for augmentation of central and lower facial features continues to increase. There are several safe and effective materials available for this purpose, and techniques have become highly refined. The relative strengths and weaknesses of silicone, expanded polytetrafluoroethylene (ePTFE), high-density polyethylene (HDPE), and merseline mesh are discussed for augmentation of the chin/pre-jowl sulcus and cheek. Materials for augmentation of the nasolabial folds (NLF) are also discussed. There are various forms of solid ePTFE that have been developed for soft tissue augmentation. These are particularly well suited for the NLF. Techniques for facial skeletal and soft tissue augmentation are presented.  相似文献   
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80.
US-guided core biopsy of the spleen in children   总被引:5,自引:0,他引:5  
PURPOSE: To evaluate the safety, diagnostic yield, and clinical benefits of performing ultrasonography (US)-guided percutaneous splenic core biopsy in children. MATERIALS AND METHODS: US-guided splenic core biopsy was performed in 30 children aged 6 months to 15.3 years (mean, 7.0 years), with focal lesions in 27 patients and homogeneous splenomegaly in three. Four patients underwent repeat biopsy to identify changes in splenic disease. Four types of biopsy needles were used in this series. General anaesthesia was used in 21 patients and conscious sedation in nine. Medical records were reviewed to assess diagnostic accuracy, influence on treatment, and biopsy-related complications. RESULTS: All biopsies were performed without complication. Among the 30 biopsies, an accurate diagnosis was obtained in 25 (83%), a false-negative result was obtained in two (7%), and three (10%) were nondiagnostic. All conclusive results influenced treatment decisions. The mean number of needle passes was 2.7 per patient (range, 2-5 passes). Use of needles was 50%-100% successful in the acquisition of adequate tissue cores. Use of the 18-gauge needle was always successful in the safe acquisition of adequate tissue, with a maximum of three passes. CONCLUSION: US-guided splenic core biopsy is a minimally invasive, simple, and safe procedure for use in children. It provides relatively high diagnostic accuracy while minimizing complications when compared with alternative, more invasive procedures.  相似文献   
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