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101.
Lars Rolighed Peter Vestergaard Lene Heickendorff Tanja Sikjaer Lars Rejnmark Leif Mosekilde Peer Christiansen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2013,398(1):113-120
Purpose
This study aims to quantify bone mineral density (BMD) changes following surgery in patients with primary hyperparathyroidism (PHPT) and to assess their relationship with clinical and biochemical variables.Methods
A historic cohort of 236 PHPT patients with DXA scans pre- and 1-year postoperatively, clinical data, and biochemical data was analyzed.Results
The mean age was 60 years (range 19–86) and 81 % of the patients were women. A significant postoperative 2.6 % (95 % CI, 2.1; 3.1) increase in lumbar spine BMD was seen. The increase in BMD was positively associated with preoperative plasma PTH (p?=?0.002), Ca2+ (p?<?0.001), and alkaline phosphatase (p?=?0.014). Hip BMD increased 1.5 % (1.1; 1.9). The increase in BMD was positively associated with preoperative plasma PTH (p?=?0.005) and Ca2+ (p?<?0.001) and inversely associated with plasma creatinine (p?=?0.004) and age (p?=?0.018). Total forearm BMD did not change significantly (?0.2 % (?0.5; 0.1)). An increase in forearm BMD was seen in 38 % of all patients, and the changes were positively associated with plasma PTH (p?<?0.001) and Ca2+ (p?=?0.009). In all 91 patients with mild PHPT (plasma Ca2+?<?1.45 mmol/l), there was a significant postoperative increase in spine BMD (1.9 % (1.2; 2.7)) and in hip BMD (1.0 % (0.4; 1.6)), but not in the forearm BMD (?0.3 % (?0.7; 0.2)). The postoperative BMD gain was higher in the hip and forearm in patients operated for adenomas compared with patients treated for hyperplasia.Conclusions
We found significant postoperative BMD improvements both at the hip and the spine. BMD improvements were also significant in mild cases. At all scan sites, there were positive associations between preoperative plasma PTH levels and postoperative BMD increases. The measured BMD changes may mainly be due to a decrease in PTH-induced bone turnover with refilling of the remodeling space. 相似文献102.
Sandra Hanne Irina A. Sekerina Shravan Vasishth Frank Burchert Ria De Bleser 《Aphasiology》2013,27(2):221-244
Background: In addition to the canonical subject-verb-object (SVO) word order, German also allows for non-canonical order (OVS), and the case-marking system supports thematic role interpretation. Previous eye-tracking studies (Kamide et al., 2003; Knoeferle, 2007) have shown that unambiguous case information in non-canonical sentences is processed incrementally. For individuals with agrammatic aphasia, comprehension of non-canonical sentences is at chance level (Burchert et al., 2003). The trace deletion hypothesis (Grodzinsky 1995, 2000) claims that this is due to structural impairments in syntactic representations, which force the individual with aphasia (IWA) to apply a guessing strategy. However, recent studies investigating online sentence processing in aphasia (Caplan et al., 2007; Dickey et al., 2007) found that divergences exist in IWAs' sentence-processing routines depending on whether they comprehended non-canonical sentences correctly or not, pointing rather to a processing deficit explanation. Aims: The aim of the current study was to investigate agrammatic IWAs' online and offline sentence comprehension simultaneously in order to reveal what online sentence-processing strategies they rely on and how these differ from controls' processing routines. We further asked whether IWAs' offline chance performance for non-canonical sentences does indeed result from guessing. Methods & Procedures: We used the visual-world paradigm and measured eye movements (as an index of online sentence processing) of controls (N?=?8) and individuals with aphasia (N?=?7) during a sentence–picture matching task. Additional offline measures were accuracy and reaction times. Outcomes & Results: While the offline accuracy results corresponded to the pattern predicted by the TDH, IWAs' eye movements revealed systematic differences depending on the response accuracy. Conclusions: These findings constitute evidence against attributing IWAs' chance performance for non-canonical structures to mere guessing. Instead, our results support processing deficit explanations and characterise the agrammatic parser as deterministic and inefficient: it is slowed down, affected by intermittent deficiencies in performing syntactic operations, and fails to compute reanalysis even when one is detected. 相似文献
103.
104.
The aim of this study was to investigate the role of the human hippocampus in episodic retrieval of odors, in comparison with episodic retrieval of visual objects. Subjects encoded a set of unique odors and objects, and retrieval was tested the next day during functional magnetic resonance imaging (fMRI). Subjects were shown the names of old (studied) and new (unstudied) odors and objects, and asked to indicate which of these stimuli had been presented the previous day. The results showed that brain activation was weaker and more restricted during retrieval of odors than during retrieval of objects, which possibly reflects a general visual dominance effect. Yet, retrieval of odors and objects yielded overlapping clusters of activation the bilateral hippocampi, and the left‐sided activation was specifically increased during successful retrieval (hits > correct rejections) in both modalities. Moreover, retrieval of odors uniquely activated olfactory cortical regions, likely to reflect cortical reinstatement of sensory details. Our fMRI study is the first to make a direct comparison between olfactory and visual episodic memory, and the results provide clear evidence for modality‐independent functions of the hippocampus. © 2012 Wiley Periodicals, Inc. 相似文献
105.
Baelum V Hintze H Wenzel A Danielsen B Nyvad B 《Community dentistry and oral epidemiology》2012,40(3):257-266
Baelum V, Hintze H, Wenzel A, Danielsen B, Nyvad B. Implications of caries diagnostic strategies for clinical management decisions. Community Dent Oral Epidemiol 2011. © 2011 John Wiley & Sons A/S Abstract – Objectives: In clinical practice, a visual–tactile caries examination is frequently supplemented by bitewing radiography. This study evaluated strategies for combining visual–tactile and radiographic caries detection methods and determined their implications for clinical management decisions in a low‐caries population. Methods: Each of four examiners independently examined preselected contacting interproximal surfaces in 53 dental students aged 20–37 years using a visual–tactile examination and bitewing radiography. The visual–tactile examination distinguished between noncavitated and cavitated lesions while the radiographic examination determined lesion depth. Direct inspection of the surfaces following tooth separation for the presence of cavitated or noncavitated lesions was the validation method. The true‐positive rate (i.e. the sensitivity) and the false‐positive rate (i.e. 1‐specificity) were calculated for each diagnostic strategy. Results: Visual–tactile examination provided a true‐positive rate of 34.2% and a false‐positive rate of 1.5% for the detection of a cavity. The combination of a visual–tactile and a radiographic examination using the lesion in dentin threshold for assuming cavitation had a true‐positive rate of 76.3% and a false‐positive rate of 8.2%. When diagnostic observations were translated into clinical management decisions using the rule that a noncavitated lesion should be treated nonoperatively and a cavitated lesion operatively, our results showed that the visual–tactile method alone was the superior strategy, resulting in most correct clinical management decisions and most correct decisions regarding the choice of treatment. 相似文献
106.
Summary
Six dual-energy X-ray absorptiometry (DXA) technicians reviewed lateral images of the spine for deformed vertebrae. The images were acquired with a DXA scanner in 235 patients referred for osteoporosis assessment. The outcome was compared to findings on spinal radiographs assessed by two radiologists. Three DXA technicians performed acceptable or better in identifying patients with fractured vertebrae.Introduction
This is the first study to evaluate the accuracy of vertebral fracture assessment (VFA) when used by DXA technicians as a triage test to select patients with deformed vertebrae for spinal radiographs.Methods
Lateral single-energy scans and radiographs of the thoracolumbar spine (T4–L4) were acquired in 235 patients aged 65 years or more referred for osteoporosis assessment. Six DXA technicians evaluated lateral scans using dedicated software. The DXA technicians were trained to identify deformed vertebrae, but they did not assess the aetiology of deformity. Two radiologists evaluated the radiographs and their consensus evaluation served as the reference test for vertebral fracture. The main outcome was sensitivity and specificity of the DXA technicians’ identification of patients with one or more grade II–III deformities according to Genant’s classification.Results
The proportion of patients with one or more grade II–III vertebral fractures was 0.35. Sensitivity ranged from 0.61 to 0.83 and specificity ranged from 0.78 to 0.95 across the DXA technicians. In patients with grade II–III deformities on VFA, the mean probability of one or more grade II–III fractures was 0.74 (range 0.66–0.86). Conversely, in patients without such deformities, the mean probability of grade II–III fractures was 0.14 (range 0.10–0.18). Accuracy was lower for grade I–III deformities for all the DXA technicians.Conclusion
Three of six DXA technicians achieved acceptable or better accuracy when using VFA to triage patients with grade II–III vertebral deformities for spinal radiographs. Heterogeneity between DXA technicians appears to be due to differences in subjective thresholds. VFA triage by DXA technicians to identify patients with grade II–III fractures is feasible.107.
Parents’ and Adolescents’ Preferences for Intensified or Reduced Treatment in Randomized Lymphoblastic Leukemia Trials 下载免费PDF全文
108.
Tveito S Maelandsmo GM Hoifodt HK Rasmussen H Fodstad O 《Clinical & experimental metastasis》2007,24(5):317-327
Molecular studies of rare cells, such as circulating cancer cells, require efficient pre-enrichment steps to obtain a pure
population of target cells for further characterization. We have developed a two-step approach, starting with immunomagnetic
enrichment, followed by specific isolation of individual, easily identifiable bead-rosetted target cells using a new semi-automated
CellPick system. With this procedure, 1–50 live target cells can now be isolated. As a model system, we spiked a small number
of tumor cells into millions of normal mononuclear cells (MNCs). Efficient isolation of pure target cells was obtained by
use of the CellPick system, and the nature of isolated, bead-rosetted cells was verified by use of FISH. Single breast cancer
cells were picked directly into an RNA preserving lysis buffer, reverse transcribed, and PCR amplified with two cDNA specific
primer sets. With the isolated cells we consistently obtained both ubiquitously expressed and tumor cell specific PCR products.
We also performed a successful mutation analysis of single cells using PCR and cycling temperature capillary electrophoresis
(CTCE). This may have significant clinical implications in cancer and in other diseases, e.g. in characterizing micrometastatic
cancer cells in blood and lymph nodes to help identifying patients who most likely will respond to therapies like tyrosine
kinase inhibitors and compounds targeting specific mutations. By use of the CellPick system it is possible to specifically
isolate bead-rosetted or otherwise labelled target cells from a heterogeneous cell population for further molecular characterization. 相似文献
109.
van Oostrom I Meijers-Heijboer H Duivenvoorden HJ Bröcker-Vriends AH van Asperen CJ Sijmons RH Seynaeve C Van Gool AR Klijn JG Tibben A 《Patient education and counseling》2007,65(1):58-68
OBJECTIVE: To study differences between individuals opting for genetic cancer susceptibility testing of a known familial BRCA1/2 and HNPCC related germline mutation. METHODS: Coping, illness perceptions, experiences with cancer in relatives and family system characteristics were assessed in 271 applicants for genetic testing before test result disclosure. Hereditary cancer distress, worry and cancer risk perception were assessed before, 1 week after, and 6 months after disclosure. RESULTS: Individuals from BRCA1/2 and HNPCC mutation families did not differ with regard to the number of experiences with cancer in relatives, grief symptoms, the course of cancer distress, worry and risk perception through time and most illness perceptions, coping responses and family characteristics. Individuals from BRCA1/2 families perceived hereditary cancer as more serious. They reported more frequently a passive coping style, cancer worry and a less open communication with their partner and children. CONCLUSION: Besides subtle differences, psychological mechanisms may be mainly identical in individuals opting for BRCA1/2 and HNPCC susceptibility testing. PRACTICE IMPLICATIONS: Based on our findings, using a similar counseling approach for individuals opting for BRCA1/2 or HNPCC genetic susceptibility testing is justified. In this approach, attention should be directed more to individual aspects than to the type of disorder. 相似文献
110.
Hanne?Nissen?Bj?rnsenEmail authorView authors OrcID profile Regine?Ringdal Geir?Arild?Espnes Mary-Elizabeth?Bradley?Eilertsen Unni?Karin?Moksnes 《BMC health services research》2018,18(1):1001