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71.
Between November 1988 and January 1992, 19,962 renal and ureteral calculi were treated in the United States using 18 different mobile and 2 fixed base Lithostar lithotriptors. Lithotripsy was performed on 11,516 renal and 8,446 ureteral calculi by 750 urologists using the same technique. The success rate (asymptomatic with stone fragments of 4 mm. or less) for renal stones was 87.9%, the stone-free rate was 68.9% and the retreatment rate was 16.5%. Auxiliary procedures were performed in 32.2% of the renal calculi. The success rate for ureteral calculi was 89.5%, the stone-free rate was 83.5% and the retreatment rate was 10.7%. Auxiliary procedures were performed in 25.5% of the ureteral calculi. The overall success rate was 88.4% stone-free rate 75.5%, retreatment rate 14.0% and auxiliary procedure rate 29.4%. Anesthesia personnel were used in 1.9% of the cases. Low energy extracorporeal shock wave lithotripsy was found to be safe and effective.  相似文献   
72.
This article briefly summarizes the work of Charles Dotter, a pioneer in interventional radiology. His enthusiasm, powers of observation, innovations, and aggressive pursuit of his ideas permitted achievement of many radiologic milestones.  相似文献   
73.
Vibrational circular dichroism (VCD) is the extension of circular dichroism (CD) from electronic to vibrational transitions in molecules. In this review, we present the basic concepts of VCD and focus on its growing strength for stereochemical applications. There are three principal areas of application of VCD. These are the determination of optical purity, the determination of absolute configuration and the determination of conformational properties of chiral molecules in solution. Until recently, the application of VCD was restricted to the use of instruments that had been custom assembled in academic research laboratories. This situation has now changed. It is possible to purchase a dedicated Fourier transform infrared (FTIR) VCD spectrometer complete with user friendly software. Combined with rapid advances in the ab initio theoretical prediction of infrared (IR) and VCD spectra, the availability of such technology opens the way for the widespread use of VCD spectroscopy for research and industrial applications.  相似文献   
74.
Ergot alkaloids are well known preparations. Ergot alkaloids used in obstetrics and gynaecology are ergometrine (ergonovine; EM), methylergometrine (methergine; ME) and bromocriptine. The pharmaceutical properties of ME EM) are critical. To guarantee stability, ME and EM ampoules should be stored in a cool, dark place. ME and EM tablets are unstable in all conditions and they show an unpredictable bioavailability, which prevents oral use of the drugs for any purpose. ME and EM are known for their strong uterotonic effect and, compared with other ergot alkaloids, for their relatively slight vasoconstrictive abilities. ME and EM do have a place in the management of the third stage of labour as they are strong uterotonics. They act differently from oxytocin and prostaglandins, and have different adverse effects. Oxytocin should be used as prophylaxis or a the drug of first choice; next, ME or EM should be used, and if none of these drugs produce the desired effects, prostaglandins should be used to control bleeding. Ergot alkaloid use in gynaecology has been limited and today is discouraged even in essential menorrhagia. It is suggested that EM and ME be used (parenterally) only in first trimester abortion curettage, to reduce blood loss. Bromocriptine has been used for lactation suppression. However, alternatives such as cabergoline, which possess fewer adverse effects, are now available and therefore preferred for this indication. In sum, there is no place for the prophylactic use of ME and EM in obstetrics or gynaecology. They can be used for therapeutic purposes in the third stage of labour. During use, the practitioner must be alert for adverse effects.  相似文献   
75.
Zinc transporter-3 (ZnT-3), a member of a growing family of mammalian zinc transporters, is expressed in regions of the brain that are rich in histochemically reactive zinc (as revealed by the Timm's stain), including entorhinal cortex, amygdala, and hippocampus. ZnT-3 protein is most abundant in the zinc-enriched mossy fibers that project from the dentate granule cells to hilar and CA3 pyramidal neurons. We show here by electron microscopy that ZnT-3 decorates the membranes of all clear, small, round synaptic vesicles (SVs) in the mossy fiber boutons of both mouse and monkey. Furthermore, up to 60-80% of these SVs contain Timm's-stainable zinc. The coincidence of ZnT-3 on the membranes of SVs that accumulate zinc, and its homology with known zinc transporters, suggest that ZnT-3 is responsible for the transport of zinc into SVs, and hence for the ability of these neurons to release zinc upon excitation.  相似文献   
76.
Bone scan has long been considered to be an important diagnostic test in searching for bone metastases. However, considerable difficulty is encountered in the vertebral region due to the complexity of structures and the fact that other benign lesions, especially degenerative changes, are very common there. Single-photon emission tomography (SPET) has been reported to be useful in the differentiation of benign from malignant conditions. Here we report our experience with bone SPET in the diagnosis of vertebral metastases. This is a retrospective study of technetium-99m methylene diphosphonate (MDP) bone scans in 174 consecutive patients who were referred for the investigation of back pain in our department. MDP planar and SPET images were obtained. Of teh 174 patients, 98 had a known history of malignant tumours. The diagnosis of vertebral metastasis was made on the basis of the patients' clinical histories and the findings with other imaging techniques such as magnetic resonance imaging, computed tomography or follow-up bone scan. We found that the presence of pedicle involvement as seen on SPET was an accurate diagnostic criterion of vertebral metastasis. SPET had a sensitivity of 87%, a specificity of 91%, a positive predictive value of 82%, a negative predictive value of 94% and an accuracy of 90%. On the other hand, planar study had a sensitivity of 74%, a specificity of 81%, a positive predictive value of 64%, a negative predictive value of 88% and an accuracy of 79% in diagnosing vertebral metastasis. Except with regard to the negative predictive value, SPET performed statistically better than planar imaging. Only 9/147 (6.4%) lesions involving the vertebral body alone and 3/49 (6.1%) lesions involving facet joints alone were subsequently found to be metastases. We conclude that bone SPET is an accurate diagnostic test for the detection of vertebral metastases and is superior to planar imaging in this respect.  相似文献   
77.
The relationship between osteoarthritis and ageing raises important questions about what exactly defines 'normal' ageing and whether the pathogenesis of osteoarthritis shares common pathways with other age-associated dysfunctions, or whether osteoarthritis is a time-dependent disorder distinct from normal ageing with a separate causative mechanism at work. Theories of ageing now emphasize the stochastic nature of the ageing process, that is the role played by accumulation of essentially random cell and tissue damage, such as somatic mutations, oxidative damage and the formation of aberrant proteins. The role of genetic factors in determining longevity and predisposition to age-associated diseases is probably in programming the efficiency of somatic maintenance functions and in influencing the development of a durable soma. Gene-environment interactions, for example through lifestyle, can also be important. Many of the risk factors and mechanisms that are thought to contribute to osteoarthritis can be accommodated within this framework.  相似文献   
78.
79.
OBJECTIVE: To evaluate the effects of supraceliac and infrarenal aortic cross-clamping on the expression of neutrophil integrin in CD11b (a marker of systemic cytokine release). DESIGN: Two groups, determined by anatomic placement of aortic cross-clamp. Laboratory personnel were blinded as to group assignment. SETTING: University teaching and community hospitals. Laboratory facilities used were university and Veteran's Affairs medical centers. PARTICIPANTS: Patients scheduled for aortic surgery. INTERVENTIONS: Blood sampling was performed at baseline, after 30 minutes of aortic cross-clamp duration, 30 and 90 minutes after reperfusion (for tumor necrosis factor-alpha plasma levels in infrarenal cross-clamp group), and at baseline and 90 minutes reperfusion (for neutrophil CD11b expression quantification) in both groups. MEASUREMENTS AND MAIN RESULTS: Tumor necrosis factor-alpha measured by ELISA technique did not change at any time period in the infrarenal clamping group. Neutrophil CD11b expression, measured by double antibody staining and FACScan analysis, did not change significantly at 90 minutes of reperfusion in the infrarenal group, but increased significantly (p < 0.05) in the supraceliac aortic cross-clamp group. CONCLUSION: Neutrophil integrin CD11b has been demonstrated to be the primary adhesive glycoprotein responsible for neutrophil organ entrapment and subsequent neutrophil-mediated reperfusion injury. These results suggest that upregulation of neutrophil integrin CD11b after supraceliac aortic clamping may in part be responsible for the higher incidence of acute lung injury after thoracic aortic aneurysm repair requiring supraceliac clamping when compared with infrarenal aneurysm surgery.  相似文献   
80.
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