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51.
Tan E Anstee A Koh DM Gedroyc W Tekkis PP 《International journal of colorectal disease》2008,23(6):641-651
Objective This study aims to evaluate the diagnostic precision of endoanal magnetic resonance imaging in identifying anal sphincter
injury and/or atrophy when compared with either endoanal ultrasound or surgical diagnosis.
Materials and methods Quantitative meta-analysis was performed on nine studies, comparing endoanal MRI with endoanal ultrasound or surgical diagnosis
in 157 patients. Sensitivity, specificity, and diagnostic odds ratio were calculated for each study. Summary receiver operating
characteristic curves (SROC) and subgroup analysis were undertaken.
Results The overall sensitivity and specificity of endoanal MRI for external sphincter injury was 0.78 (95%CI: 0.66–0.84) and 0.66
(95%CI: 0.51–0.79), respectively. For internal sphincter injury detection, this was 0.63 (95%CI: 0.50–0.74) and 0.71 (95%CI:
0.60–0.81), respectively. For detection of atrophy, this was 0.86 (95%CI: 0.71–0.95) and 0.82 (95%CI: 0.65–0.93), respectively.
The area under the SROC curve and diagnostic odds ratio were 0.84 (SE = 0.07) and 6.14 (95%CI: 2.17–17.4) for external sphincter
injury, 0.79 (SE = 0.07) and 4.60 (95%CI: 1.75–12.15) for internal sphincter injury, and 0.92 (SE = 0.08) and 21.49 (95%CI:
2.87–160.64) for sphincter atrophy.
Conclusion Endoanal MRI was sensitive and specific for the detection of external sphincter injury and especially sphincter atrophy. It
may be useful as an alternative to endoanal ultrasound in patients presenting with fecal incontinence, although further clinical
studies are needed to identify its best application in clinical practice. 相似文献
52.
Thyroid destruction leading to endemic myxoedematous cretinism is highly prevalent in central Africa, where iodine (I) and selenium (SE) deficiencies as well as thiocyanate (SCN) overload are combined. All three factors have been studied experimentally in the etiology of the disease, but they have never been studied in combination. In a model using rats, we have previously shown that combining I and SE deficiencies increases the sensitivity of the thyroid to necrosis after iodide overload, an event unlikely to occur in the African situation. To develop a model that would more closely fit with the epidemiological findings, we have determined whether an SCN overload would also result in thyroid necrosis as does the I overload. The combination of the three factors increased by 3.5 times the amount of necrotic cells, from 5.5 +/- 0.3% in the I-SE+ thyroids to 18.9 +/- 1.6% in the I-SE-SCN-overloaded ones. Methimazole administration prevented the SCN-induced necrosis. SE- thyroids evolved to fibrosis, whereas SE+ thyroids did not. TGFbeta was prominent in macrophages present in SE- glands. Thyroid destruction in central Africa might therefore originate from the interaction of three factors: I and SE deficiencies by increasing H(2)O(2) accumulation, SE deficiency by decreasing cell defense and promoting fibrosis, and SCN overload by triggering follicular cell necrosis. 相似文献
53.
We describe a patient with a subacute inferior myocardial infarction who developed a pseudo-aneurysm more than 18 days after the acute event. This is an unusual case with three different complications of a myocardial infarction: Firstly, ventricular rupture is usually the result following transmural myocardial infarction without reperfusion. However, coronary angiography confirmed reperfusion after late thrombolysis in this patient. The subacute rupture could potentially be caused or aggravated by the late thrombolysis. Secondly, this patient developed a mural apical thrombus in a non-infarcted region. It seems most likely that the new infarct caused a low flow state which enhanced thrombus formation. Against expectations, this developed at the apex rather than the site of the recent inferior wall myocardial infarction. Thirdly, we documented the development of a pseudo-aneurysm more than 18 days after the myocardial infarction. This complication is rarely seen at this stage after a myocardial infarction, as most pseudo-aneurysms are formed within 7 days after a myocardial infarction. We have beautifully visualised the apical thrombus and pseudo-aneurysm with echocardiography. This report shows that serial echocardiography is a very useful tool in evaluating the patient's clinical and cardiac status in the period after a myocardial infarction. 相似文献
54.
Data upon age at menarche have been collected among 254 schoolgirls of a relatively endogamous rural population in central France. The median age at menarche estimated by probits was 13·05±0·18, SD1·42. This accords well with results obtained from urban samples in the years 1965–68. Both rural and urban samples give a median age 0·5 year earlier than data from a national survey performed in 1950. 相似文献
55.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231
Background
Primary care is increasingly interested in the identification of frailty, as it selects the target population for integrated care. However, instruments for the identification of frailty specifically validated for use in primary care are scarce. This study developed the Easycare Two-step Older persons Screening (Easycare-TOS), which provides a valid, efficient, and pragmatic screening procedure to identify frail older people.Aim
This paper aims to describe the development of the Easycare-TOS and the data from the pilot studies.Design and setting
Observational pilot study in seven academic GP practices in and around Nijmegen, The Netherlands.Method
The Easycare-TOS was developed in a cyclic process with the input of stakeholders. In every cycle, the requirements were first defined, then translated into a prototype that was tested in a pilot study. The Easycare-TOS makes optimal use of prior knowledge of the GP, and the professionals’ appraisal is decisive in the frailty decision, instead of a cut-off score. Further, it considers aspects of frailty, as well as aspects of the care context of the patient.Results
The pilot data have shown that after step 1, two-thirds of the patients do not need further assessment, because they are judged as not frail, based on prior knowledge of the GP. The overall prevalence of frailty in this pilot study is 24%. Most professionals who participated in the pilot studies considered the time investment acceptable and the method to be of added value.Conclusion
The Easycare-TOS instrument meets the predefined efficiency, flexibility, and acceptability requirements for use as an identification instrument for frailty in primary care. 相似文献56.
Emile Simon Xavier Perrot Michel Linne Afif Afif Guillaume Becq Patrick Mertens 《Surgical and radiologic anatomy : SRA》2013,35(2):115-124
Purpose
Subjective tinnitus is considered a phantom auditory phenomenon. Recent studies show that electrical or magnetic stimulation of the cortex can alleviate some tinnitus. The usual target of the stimulation is the primary auditory cortex (PAC) on Heschl’s gyrus (HG). The objective of this study was to specify the anatomy of HG by magnetic resonance imaging (MRI).Methods
Cerebral MRI of 60 patients with chronic tinnitus, carried out before neuronavigated repetitive transcranial magnetic stimulation targeting the auditory cortex, were included. 3D-T1 MRI was reformatted in Talairach–Tournoux’s stereotactic space, then the following steps were performed: morphometry of HG, localization of the probabilistic center of the PAC (pcPAC) chosen at the junction between the medial third and the lateral two-thirds of HG, relative to external and cortical landmarks, and identification of its coordinates relative to the bicommissural line (AC-PC).Results
In relation to external landmarks, the pcPAC was identified around 5 cm above the root of the helix of the ear in the direction of a point on the vertex located 4 cm behind the coronal suture, for both sides. In Talairach–Tournoux’s stereotactic space with the anterior commissure as the origin, the pcPAC coordinates were x = 43, y = ?20, z = 6.8 on the right side, and x = ?42.5, y = ?21.5, and z = 6.5 on the left. Probabilistic maps of the presence of HG pointed to a relative contraction of data in space, despite inter- and intraindividual differences.Conclusion
The choice of our stimulation target was established in the middle of the theoretical position of the PAC. MRI allows a reliable identification of the target structure. 相似文献57.
58.
59.
Cyril Touboul Marcos Ballester Gil Dubernard Sonia Zilberman Anne Thomin Emile Daraï 《Surgical endoscopy》2015,29(7):1879-1887
60.
Packham MA; Perry DW; Kinlough-Rathbone RL; Rand ML; Guccione MA; Evans RM; Mustard JF 《Blood》1985,65(3):564-570
Rabbit platelets were aggregated by adenosine diphosphate (ADP), allowed to deaggregate and then separated into density subpopulations by centrifugation through discontinuous Stractan density gradients. Although ADP causes little or no release of the contents of the amine storage granules of rabbit platelets, ADP caused a decrease in platelet density as compared with control platelets subjected to the same procedures except for exposure to ADP. The density change persisted for at least four hours. The apparent size of platelets stimulated with ADP increased initially, but returned to control values during a one-hour period. A similar decrease in platelet density was observed with an albumin density gradient. Under conditions in which aggregation did not occur in response to ADP with ethylenediaminetetraacetic acid (EDTA) in the medium, little or no decrease in platelet density was observed. Agglutination with polylysine did not change platelet density. Thus, not only agents such as thrombin and plasmin that cause the release of the contents of the platelet granules decrease platelet density, but ADP also has this effect. Platelets would be exposed to all of these stimuli during thromboembolic processes, and their effect on platelets may account for the decrease in platelet density observed previously in experiments with rabbits with indwelling aortic catheters. Agents that increase the concentration of cyclic AMP (cAMP) in platelets (PGE1, adenosine, dibutyryl cAMP, forskolin, and papaverine) also decreased platelet density. This effect persisted when the platelets were washed and resuspended in fresh medium and was also demonstrable in plasma. Platelet size was gradually increased by prostaglandin E1 (PGE1) which maintains platelets in a disc shape and does not cause the release of granule contents, indicating that the decrease in platelet density caused by PGE1 may be attributable to platelet swelling. 相似文献