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排序方式: 共有767条查询结果,搜索用时 15 毫秒
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Nancy Morabito Agostino Gaudio Antonino Lasco Antonino Catalano Marco Atteritano Aldo Trifiletti Giuseppina Anastasi Darwin Melloni Nicola Frisina 《Journal of bone and mineral research》2004,19(11):1766-1770
Today, androgen deprivation therapy is a cornerstone of treatment for advanced prostate cancer, although it presents important complications such as osteoporosis. Neridronate, a relatively new bisphosphonate, is able to prevent bone loss in patients with prostate cancer during androgen ablation. INTRODUCTION: Androgen-deprivation therapy (ADT) is a cornerstone of treatment for advanced prostate cancer. This therapy has iatrogenic complications, such as osteoporosis. The aim of our study was to evaluate the efficacy of neridronate, a relatively new bisphosphonate, to prevent bone loss during androgen ablation. MATERIALS AND METHODS: Forty-eight osteoporotic patients with prostate cancer, treated with 3-month depot triptorelina, were enrolled and randomly assigned to two different treatment groups: group A (n = 24) was treated with a daily calcium and cholecalciferol supplement (500 mg of elemental calcium and 400 IU cholecalciferol), and group B (n = 24) received in addition to the same daily calcium and cholecalciferol supplement, 25 mg of neridronate given intramuscularly every month. All patients also received bicalutamide for 4 weeks. Lumbar and femoral BMD was evaluated by DXA at baseline and after 1 year of therapy; moreover, deoxypyridinoline (DPD) and bone alkaline phosphatase (BALP) were determined at the beginning, midway through, and at the end of the study. RESULTS: After 6 and 12 months, whereas patients treated only with calcium and cholecalciferol (group A) showed a marked bone loss, with increased levels of DPD and BALP compared with baseline values, patients treated also with neridronate (group B) had substantially unchanged levels of these markers. After 1 year of treatment, lumbar and total hip BMD decreased significantly in patients treated only with calcium and cholecalciferol (group A), whereas it did not change significantly at any skeletal site in patients treated also with neridronate (group B). No relevant side effects were recorded during our study. CONCLUSIONS: Neridronate is an effective treatment in preventing bone loss in the hip and lumbar spine in men receiving ADT for prostate cancer. 相似文献
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P Darwin Bell Jean-Yves Lapointe 《Clinical and experimental pharmacology & physiology》1997,24(7):541-547
1. Macula densa (MD) cells are located within the thick ascending limb (TAL) and have their apical surface in contact with tubular fluid and their basilar region in contact with the glomerulus. These cells sense changes in luminal fluid sodium chloride concentration ([NaCl]) and transmit signals resulting in changes in vascular resistance (tubuloglomerular feedback) and renin release. 2. Current efforts have focused on understanding the cellular transport mechanisms of MD cells. Progress in this area has benefited from the use of the isolated perfused TAL-glomerular preparation, which permits direct access to MD cells. 3. Using microelectrodes to measure basolateral membrane potential (VBL) of MD cells, it was found that VBL was very sensitive to changes in luminal fluid [NaCl]. As [NaCl] was elevated from 20 to 150mmol/L, VBL was found to depolarize by over 30 mV. 4. Basolateral membrane potential measurements were also used to identify an apical Na+: 2CI?: K+ cotransport pathway in MD cells that is the major pathway for NaCl entry into these cells. 5. Other work identified a basolateral chloride channel that is presumed to be responsible for changes in VBL during alterations in luminal [NaCl]. This channel, which is the predominant conductance across the basolateral membrane, may be regulated by intracellular Ca2+ and cAMP. 6. An apical Na+: H+ exchanger in MD cells was detected by measuring changes in intracellular pH using the fluorescent probe 2′,7′-bis-(2-carboxyethyl)-5(and-6) carboxyfluorescein. 7. Using patch-clamp techniques, a high density of pH- and Ca2+-sensitive K+ channels was observed at the apical membrane of MD cells. 8. Other studies found that, at the normal physiological conditions prevailing at the end of the TAL (luminal [NaCl] of 20–60 mmol/L), reabsorption mediated by MD cells is very sensitive to changes in luminal [NaCl]. 相似文献
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The ability of an observer to detect variations in size of a geometrical image feature have been investigated using receiver operating characteristic (ROC) analysis. Three types of image were constructed using computer graphics: disc-shaped targets of variable radius, model chest radiographs showing a variable heart diameter and model arterial angiograms with variable vessel width. Five factors were investigated: observer experience, variation of detectability with theoretical signal-to-noise ratio, the prior probability of the presence of an abnormality, viewing distance, and uncertainty in the location of an abnormality. In all but one experiment, excellent agreement was found between measured detectabilities and the predictions of signal detection theory, providing an initial practice session was included for each observer. No significant variation in detectability was found using six different prior probabilities and two different viewing distances, and the reduction in detectability for a four-alternative location task was in good agreement with theoretical predictions. The high statistical efficiencies found for the detection of geometrical signals suggest that the levels of observer "internal" noise arising from decision-making processes during an ROC experiment are very low. 相似文献
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Comparison of Digene hybrid capture 2 and conventional culture for detection of Chlamydia trachomatis and Neisseria gonorrhoeae in cervical specimens 总被引:4,自引:0,他引:4 下载免费PDF全文
Darwin LH Cullen AP Arthur PM Long CD Smith KR Girdner JL Hook EW Quinn TC Lorincz AT 《Journal of clinical microbiology》2002,40(2):641-644
Digene's Hybrid Capture 2 (HC2) CT/GC, CT-ID, and GC-ID DNA tests were evaluated by comparison to traditional culture methods for detecting Chlamydia trachomatis and Neisseria gonorrhoeae infections in 669 cervical specimens from high-risk female populations attending two sexually transmitted disease clinics. For detection of either or both infections, the HC2 CT/GC test algorithm had 93.8% sensitivity and 95.9% specificity compared to those of culture. After resolution of discrepant results by direct fluorescent-antibody (DFA) staining or PCR assay, the relative sensitivity and specificity of the HC2 CT/GC test algorithm increased to 94.8 and 99.8%, while the values for culture were 83.6% (McNemar's P value, 0.0062) and 100%, respectively. For detection of the individual pathogens, the relative sensitivities for the HC2 CT-ID and GC-ID tests were 97.2 and 92.2% and the specificities were greater than 99% compared to culture adjucated by DFA staining and PCR. Test performance varied at the two clinics: the HC2 CT/GC algorithm, CT-ID, and GC-ID tests had significantly higher sensitivities (McNemar's P value, <0.05) than that of culture for the population at one clinic as well as for the combined populations. At the other clinic, the HC2 tests performed as well as culture. 相似文献
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Christopher J. Percival Jay Devine Benjamin C. Darwin Wei Liu Matthijs van Eede R. Mark Henkelman Benedikt Hallgrimsson 《Journal of anatomy》2019,234(6):917-935
Morphometric analysis of anatomical landmarks allows researchers to identify specific morphological differences between natural populations or experimental groups, but manually identifying landmarks is time‐consuming. We compare manually and automatically generated adult mouse skull landmarks and subsequent morphometric analyses to elucidate how switching from manual to automated landmarking will impact morphometric analysis results for large mouse (Mus musculus) samples (n = 1205) that represent a wide range of ‘normal’ phenotypic variation (62 genotypes). Other studies have suggested that the use of automated landmarking methods is feasible, but this study is the first to compare the utility of current automated approaches to manual landmarking for a large dataset that allows the quantification of intra‐ and inter‐strain variation. With this unique sample, we investigated how switching to a non‐linear image registration‐based automated landmarking method impacts estimated differences in genotype mean shape and shape variance‐covariance structure. In addition, we tested whether an initial registration of specimen images to genotype‐specific averages improves automatic landmark identification accuracy. Our results indicated that automated landmark placement was significantly different than manual landmark placement but that estimated skull shape covariation was correlated across methods. The addition of a preliminary genotype‐specific registration step as part of a two‐level procedure did not substantially improve on the accuracy of one‐level automatic landmark placement. The landmarks with the lowest automatic landmark accuracy are found in locations with poor image registration alignment. The most serious outliers within morphometric analysis of automated landmarks displayed instances of stochastic image registration error that are likely representative of errors common when applying image registration methods to micro‐computed tomography datasets that were initially collected with manual landmarking in mind. Additional efforts during specimen preparation and image acquisition can help reduce the number of registration errors and improve registration results. A reduction in skull shape variance estimates were noted for automated landmarking methods compared with manual landmarking. This partially reflects an underestimation of more extreme genotype shapes and loss of biological signal, but largely represents the fact that automated methods do not suffer from intra‐observer landmarking error. For appropriate samples and research questions, our image registration‐based automated landmarking method can eliminate the time required for manual landmarking and have a similar power to identify shape differences between inbred mouse genotypes. 相似文献
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Summary A differential plating method permitted preparation of cultures significantly enriched for Type II pneumocytes. These cells were maintained in a differentiated state for at least 12 d, identifiable morphologically (by presence of osmiophilic lamellar inclusion bodies) and bio-chemically (by demonstration of synthesis of phosphatidyl choline and production of disaturated lecithin). 相似文献
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Diletta La Torre Sandra Isgrò Maria Rosaria Anna Muscatello Carlo Magno Darwin Melloni Mario Meduri 《International journal of psychiatry in clinical practice》2013,17(2):116-119
ObjectiveThe present study was a urodynamic evaluation of schizophrenic patients with urinary incontinence occurring during treatment with atypical antipsychoticsMethodsA total of 12 schizophrenic patients (mean age?=?30.7 years, SD?=?6.5) presenting urinary incontinence during treatment with atypical antipsychotics at stable doses underwent urodynamic evaluations. Clinical assessment included the administration of Positive and Negative Syndrome Scale (PANSS)ResultsFour patients out of 12 presented urodynamic patterns consistent with an overactive bladder, while five patients presented reduced bladder compliance; only three patients showed normal urodynamic patternsConclusionDetrusor overactivity is a condition associated with urinary incontinence in schizophrenic patients treated with atypical antipsychotics. Urodynamic evaluations can improve our knowledge of the mechanisms that subtend atypical antipsychotic-induced incontinence, an invalidating side-effect with strong repercussion on compliance and rehabilitation in schizophrenic patients 相似文献
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Diagnosing CP can range from routine in those with severe disease and obvious calcifications on CT imaging to elusive in those patients with early changes in CP. The workup of suspected CP should follow a progressively noninvasive to more invasive STEP-wise approach in a patient with a suspicious clinical presentation and risk factors that raise their pretest probability of disease. After a thorough history and physical examination, basic laboratories should be obtained such as lipase, amylase, metabolic panel, and indirect PFTs (fecal elastase-1, serum trypsin). Computed tomography remains the best initial imaging modality to obtain as it has good sensitivity for severe CP and may obviate the need for other diagnostic tests. When equivocal, an MRCP should be obtained for a more detailed evaluation of the both the pancreatic parenchyma and ducts. If the diagnosis remains in doubt, EUS should be performed with or without pancreas function testing. ERCP remains a last-line diagnostic test and seldom should be used outside of therapeutic purposes. Future advances should target optimizing current diagnostic tools to more accurately diagnose early CP, as it is in this population where the benefits of delaying progression of CP may have the most profound effect. Likely the best way at establishing a diagnosis in these patients is via pancreatic function testing in the setting of indeterminate EUS results. Biomarker studies of pancreas fluid may supplement diagnosis. 相似文献