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Defects involving the distal leg and foot are frequently encountered following various aetiological factors. Paucity of local tissue causes surgeons to resort to the retrograde peninsular flap, the cross leg flap or the free flap. With specific knowledge of perforators, the fasciocutaneous flap from the calf area can be transferred to the defect in a single stage based on skeletonised distal perforators. The surgical anatomy, flap planning and procedure have been detailed. Nineteen patients were treated during the period 1995 to 2005. The perforators were identified preoperatively by audio Doppler. The flaps were marked and dissected proximal to the defect skeletonising the distal perforators under loupe magnification and transferred to the defect in a single stage. The donor site was skin grafted. Out of 19 cases, 16 flaps healed uneventfully, one flap necrosed completely and in two cases there was marginal necrosis. The cases were followed up for 2-10 years with an average of 6 years. With detailed knowledge of perforators one can safely reconstruct distal moderate-size defects of the lower limb in a single stage, thus having the benefits of free tissue transfer without resorting to microsurgery. This technique has proved to be an advancement in the reconstructive repertoire allowing flaps of non conventional dimensions to be perfused by skeletonised perforators.  相似文献   
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Several lines of evidence from neuroimaging, pharmacology and genetics support the involvement of the dopaminergic system in the etiology of Attention Deficit Hyperactivity Disorder (ADHD). Previous candidate gene studies have investigated the association between a dinucleotide (CA)n repeat polymorphism, located 18.5 kb from the start codon of the DRD5 gene, and ADHD. Association between the 148 bp allele and ADHD has been reported in some studies, however replication of the finding has not been consistent. We tested for an association between the (CA)n repeat and adult ADHD in a sample comprised of 119 families with adult ADHD probands and 88 unrelated adult ADHD cases with a corresponding number of controls matched for age, ethnicity and sex. In the family sample we found a non-significant trend for association between the 148 bp allele and ADHD (Z = 1.91, p = 0.055). An excess of non-transmissions was detected for the 150 and 152 bp alleles (Z = −2.26, p = 0.023; Z = −2.20, p = 0.028). Quantitative analysis performed using the Brown Attention Deficit Disorder Scale (BADDS) showed association between the 150 bp allele and lower total score (p = 0.011), and lower effort (p = 0.008), activation (p = 0.008) and attention (p = 0.01) cluster scores. We did not replicate association findings in the case–control group, likely due to the lack of statistical power of this sample. Our findings add to the literature suggesting DRD5 (CA)n repeat has a modest effect in modulating susceptibility to adult ADHD but further studies are required.  相似文献   
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Rising incidence and mortality of cancer have led to an incremental amount of research in the field. To learn from preexisting data, it has become important to capture maximum information related to disease type, stage, treatment, and outcomes. Medical imaging reports are rich in this kind of information but are only present as free text. The extraction of information from such unstructured text reports is labor-intensive. The use of Natural Language Processing (NLP) tools to extract information from radiology reports can make it less time-consuming as well as more effective. In this study, we have developed and compared different models for the classification of lung carcinoma reports using clinical concepts. This study was approved by the institutional ethics committee as a retrospective study with a waiver of informed consent. A clinical concept-based classification pipeline for lung carcinoma radiology reports was developed using rule-based as well as machine learning models and compared. The machine learning models used were XGBoost and two more deep learning model architectures with bidirectional long short-term neural networks. A corpus consisting of 1700 radiology reports including computed tomography (CT) and positron emission tomography/computed tomography (PET/CT) reports were used for development and testing. Five hundred one radiology reports from MIMIC-III Clinical Database version 1.4 was used for external validation. The pipeline achieved an overall F1 score of 0.94 on the internal set and 0.74 on external validation with the rule-based algorithm using expert input giving the best performance. Among the machine learning models, the Bi-LSTM_dropout model performed better than the ML model using XGBoost and the Bi-LSTM_simple model on internal set, whereas on external validation, the Bi-LSTM_simple model performed relatively better than other 2. This pipeline can be used for clinical concept-based classification of radiology reports related to lung carcinoma from a huge corpus and also for automated annotation of these reports.

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The patient with goiter and his or her physician frequently overlook symptoms of upper respiratory obstruction. Conventional radiology is the accepted method for detecting upper airway obstruction in these patients. Flow volume loops provide additional information on airflow dynamics. Twenty-five patients of goiter undergoing surgery were evaluated for upper airway obstruction by symptomatology, conventional radiology, and flow volume loops. Flow volume loops were repeated 1 month after surgery. Ten (40%) patients had mild symptoms on direct questioning. Tracheal deviation, compression, or both were noted in eight (32%) patients on radiology. Flow volume loops detected upper airway obstruction in 15 (60%) patients. Surgery resulted in normalization of all preoperative abnormal curves. The flow volume loop is a simple noninvasive method for detecting upper airway obstruction in patients with goiter. Abnormal upper airway dynamics are present in more patients with goiter than previously recognized, and relief of this obstruction should be an important aspect of thyroid surgery.  相似文献   
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Synergistic liver injury develops in Sprague-Dawley rats from administration of a small, noninjurious dose (7.4 x 10(6) EU/kg) of bacterial lipopolysaccharide (LPS) given 4 h after a nontoxic dose (100 mg/kg) of the pyrrolizidine alkaloid, monocrotaline (MCT). Previous studies demonstrated that liver injury is mediated through inflammatory factors, such as Kupffer cells and tumor necrosis factor alpha (TNF-alpha), rather than through simple interaction between MCT and LPS. In the present study, the hypothesis that neutrophils (polymorphonuclear leukocytes or PMNs) are causally involved in this injury model is tested, and the interdependence between PMNs and other inflammatory components is explored. Hepatic PMN accumulation and the appearance of cytokine-induced neutrophil chemoattractant-1 in plasma preceded the onset of liver injury, suggesting that PMNs contribute to toxicity. Hepatic PMN accumulation was partially dependent on TNF-alpha. Prior depletion of PMNs in MCT/LPS-cotreated animals resulted in attenuation of both hepatic parenchymal cell (HPC) and sinusoidal endothelial cell (SEC) injury at 18 h. PMN depletion did not, however, protect against early SEC injury that occurred before the onset of HPC injury at 6 h. This observation suggests that SEC injury is not entirely dependent on PMNs in this model. In vitro, MCT caused PMNs to degranulate in a concentration-dependent manner. These results provide evidence that PMNs are critical to the HPC injury caused by MCT/LPS cotreatment and contribute to the progression of SEC injury.  相似文献   
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Medullary thyroid carcinoma (MTC) is an uncommon malignancy of neuroendocrine origin derived from the parafollicular C cells. Although infrequent, the interest in this cancer exceeds its incidence owing to its distinctive features and its characteristic association with other endocrine tumors. Although the majority of MTCs are sporadic, hereditary varieties occur in isolation or as a part of multiple endocrine neoplasia type 2 syndrome (MEN 2). Currently, complete surgical resection of the tumor and nodal metastases with a curative intent remains the mainstay of therapy. The role of adjuvant therapy is limited, although radiotherapy and newer targeted therapies are routinely used for metastatic disease. The lack of consensus in the available guidance regarding the most appropriate diagnostic, therapeutic and follow-up strategies has caused substantial variability in clinical practice. Therefore, this review summarizes the latest available evidence and guidelines on the management of MTC with an emphasis on diagnosis, surgical treatment and follow-up.  相似文献   
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Purpose:To compare the efficacy of Kane formula with Sanders Retzlaff Kraff/Theoretical (SRK/T) and Barrett Universal II in predicting intraocular lens (IOL) power in Indian eyes.Methods:This retrospective study conducted in a tertiary care eye hospital. Data from patients having uneventful cataract surgery with Tecnis ZCB00 IOL implantation were obtained from Lenstar and electronic medical records. Eyes were divided into subgroups based on axial length (AL) as short (<22.0 mm), medium (22–24 mm), and long (>24 mm). The predicted refractive outcome for each patient was calculated after optimizing the lens constant. Prediction error was calculated by subtracting the predicted spherical equivalent from achieved spherical equivalent 1 week post-surgery. The mean absolute error (MAE) and median absolute error (MedAE) and percentage of eyes within 0.25, 0.5, 1, and 2 D were calculated for each formula. Friedman test, Cochrane Q test were used for statistical analysis.Results:Out of the 350 eyes included in the study, we found that without lens constant optimization, Barrett formula performed better than SRK/T and Kane (P < 0.0001). Over the entire range of axial lengths, Kane formula performed slightly inferior compared to Barrett and SRK-T, both of which performed equally well (P = 0.006). On subgroup analysis, Kane formula performed inferiorly for medium eyes as compared to the other two. No significant differences were noted between the formulae for short and long eyesConclusion:Kane formula did not outperform Barrett Universal II and SRK/T in Indian eyes.  相似文献   
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We present a rare case of a 50-year old lady who presented with pain abdomen and bleeding per vaginum of 3 months duration. Per vaginal examination revealed an exophytic growth arising from vault. Histopathological examination of the vault biopsy showed malignant neoplasm with features suggestive of carcinosarcoma of vault with immunohistochemistry showing stromal cells positive for CD10 and negative for SMA. Ki67 index was 40%-50%. She received external beam radiotherapy to pelvis 50.4 Gy/25 fractions but did not respond to the same. The lesion was not surgically resectable and hence referred to the division of medical oncology for chemotherapy. She was started on ifosphamide with cisplatin with growth factor support. It was planned to do a reassessment after 3 cycles of chemotherapy, but patient succumbed to the illness.  相似文献   
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