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1.
2.
The diagnostic potential of CT and sonography in detecting clinically unrecognized cases of spigelian hernia is illustrated and discussed. These imaging modalities can promptly and reliably diagnose spigelian hernia based on the following findings: (1) peritoneal and muscular defect along the spigelian line in the lower abdomen; (2) intraparietal location of the hernial sac; and (3) hernial sac containing omentum and/or mesentery and loops of bowel. Two recently diagnosed cases are presented together with a short review of the literature.  相似文献   
3.
Familial Hypocalciuric Hypercalcaemia (FHH) Type 1 is caused by an inactivating mutation in the calcium-sensing receptor (CASR) gene resulting in elevated plasma calcium levels. We investigated whether FHH is associated with change in bone density and structure. We compared 50 FHH patients with age- and gender-matched population-based controls (mean age 56 years, 69 % females). We assessed areal BMD (aBMD) by DXA-scans and total, cortical, and trabecular volumetric BMD (vBMD) as well as bone geometry by quantitative computed tomography (QCT) and High-Resolution peripheral-QCT (HR-pQCT). Compared with controls, FHH females had a higher total and trabecular hip vBMD and a lower cortical vBMD and hip bone volume. Areal BMD and HRpQCT indices did not differ except an increased trabecular thickness and an increased vBMD at the transition zone between cancellous and cortical bone in of the tibia in FHH. Finite element analyses showed no differences in bone strength. Multiple regression analyses revealed correlations between vBMD and P-Ca2+ levels but not with P-PTH. Overall, bone health does not seem to be impaired in patients with FHH. In FHH females, bone volume is decreased, with a lower trabecular volume but a higher vBMD, whereas cortical vBMD is decreased in the hip. This may be due to either an impaired endosteal resorption or corticalization of trabecular bone. The smaller total bone volume suggests an impaired periosteal accrual, but bone strength is not impaired. The findings of more pronounced changes in females may suggest an interaction between sex hormones and the activity of the CaSR on bone.  相似文献   
4.

Background/Purpose

Intrathyroidal thymic tissue may be misinterpreted as a thyroid lesion in children, leading to invasive tests or resection. We sought to describe the characteristic imaging features of these lesions and to evaluate the safety of non-operative management.

Methods

A retrospective review of all patients less than 18 years old with intrathyroidal thymic tissue from 2000 to 2016 was performed. Data collection included patient demographics, imaging results, interventions, and outcomes.

Results

Eleven patients were identified using institutional radiology and pathology databases. Median patient age and lesion size at presentation were 5 years old (range 2 to 8 years old) and 0.9 cm (range 0.4 to 9.2 cm), respectively. Six lesions were incidentally identified, six were left-sided, and the most common location was the lower pole. Ultrasonographic features were reproducible and included well demarcated (10/11), hypoechoic lesions (11/11), containing punctate/linear internal echoes (11/11), and occasional mild hypervascularity (6/11). All cases demonstrated interval size and echotexture stability over a median surveillance period of 3 years (range 1 to 8 years). While 9 patients were simply observed, the first patient in this series underwent excision, while another had a fine needle aspiration to confirm pathology.

Level of Evidence

Study of diagnostic test, Level IV.

Conclusion

Intrathyroidal thymic tissue has typical clinical and sonographic characteristics which allow for appropriate diagnosis and avoids thyroid resection.  相似文献   
5.

Background

Total parenteral nutrition (TPN) is often used in children with perforated appendicitis, despite the absence of clear indications. We assessed the validity of specific clinical indications for initiation of TPN in this patient cohort.

Methods

Data were gathered prospectively on duration of nil per os (NPO) status and TPN use in a cohort of children treated under a perforated appendicitis protocol during a 19-month period. TPN was started in the immediate postoperative period in patients who had generalized peritonitis and severe intestinal dilatation at operation, or later per the discretion of the attending surgeon. At discharge, TPN was considered to have been used appropriately, according to consensus guidelines, if the patient was NPO  7 days or received TPN  5 days.

Results

During the study period, TPN was initiated in 31 (25.4%) of 122 patients operated for perforated appendicitis. Sixteen (51.6%) received TPN per operative finding indications and 15 (48.4%) for prolonged ileus. The operative indications demonstrated 47% sensitivity, 86% specificity, a positive predictive value (PPV) of 35%, and a negative predictive value (NPV) of 91%, when adherence to TPN consensus guidelines was considered the gold standard.

Conclusion

Patients without severe intestinal dilatation and generalized peritonitis at operation should not be placed on TPN in the immediate postoperative period. Refinement of selection criteria is necessary to further decrease inappropriate TPN use in children with perforated appendicitis.

Type of study

Diagnostic Test.

Level of study

II  相似文献   
6.
Organ transplantation is limited by access to suitable organs. Infant recipient waitlist mortality is increased due to the scarcity of size-matched organs. Neonatal organ donors have been proposed as an underutilized source of donor organs. However, the literature on the actual prevalence and outcome of neonatal organ donation and transplantation is fragmented and not well analyzed. This literature review aims to summarize the available literature on the potential of neonatal organ donation and to analyze published cases of neonatal organ transplantation. A systematic search of the Medline and Cochrane databases yielded 2964 articles, which were screened for eligibility. In total, 86 articles were considered eligible, of which 34 were included in the literature review: 8 articles describing the potential of neonatal organ donation programs, and 26 articles describing clinical transplantation. Current evidence suggests there is a large pool of potential neonatal organ donors. In contrast, the literature on neonatal organ donor utilization is sparse. However, case series of successful kidney, heart, liver, hepatocyte, and multivisceral transplantation using organs from neonatal donors are summarized. Although good posttransplant organ function was achieved, the use of neonatal organs is associated with increased risk of thrombosis in both kidney and liver transplantation. Neonatal organ donation is a promising alternative for expanding the current donor pool. Experience is limited, but reported patient and graft survival are acceptable and more research on the subject is warranted.  相似文献   
7.

Study Design

Cross-sectional.

Purpose of the Study

This study evaluates finger flexion and extension strengthening exercises using elastic resistance in chronic stroke patients.

Methods

Eighteen stroke patients (mean age: 56.8 ± 7.6 years) with hemiparesis performed 3 consecutive repetitions of finger flexion and extension, using 3 different elastic resistance levels (easy, moderate, and hard). Surface electromyography was recorded from the flexor digitorum superficialis (FDS) and extensor digitorum (ED) muscles and normalized to the maximal electromyography of the non-paretic arm.

Results

Maximal grip strength was 39.2 (standard deviation: 12.5) and 7.8 kg (standard deviation: 9.4) in the nonparetic and paretic hand, respectively. For the paretic hand, muscle activity was higher during finger flexion exercise than during finger extension exercise for both ED (30% [95% confidence interval {CI}: 19-40] vs 15% [95% CI: 5-25] and FDS (37% [95% CI: 27-48] vs 24% [95% CI: 13-35]). For the musculature of both the FDS and ED, no dose-response association was observed for resistance and muscle activity during the flexion exercise (P > .05).

Conclusion

The finger flexion exercise showed higher muscle activity in both the flexor and extensor musculature of the forearm than the finger extension exercise. Furthermore, greater resistance did not result in higher muscle activity during the finger flexion exercise. The present results suggest that the finger flexion exercise should be the preferred strengthening exercise to achieve high levels of muscle activity in both flexor and extensor forearm muscles in chronic stroke patients. The finger extension exercise may be performed with emphasis on improving neuromuscular control.

Level of Evidence

4b.  相似文献   
8.
9.
10.
Rabbits immunized to different heterologous renal antigens developed antibodies some of which are fixed to their own glomeruli (autoantibodies). These autoantibodies, reacting with the host's kidneys, were directed to those antigenic determinants which were present in identical or cross-reactive form in both the immunizing antigen and the kidneys of the host. Glomerulonephritis developed in some of the rabbits immunized to heterologous mammalian kidneys, but in none of those immunized to nonmammalian kidneys. The development of glomerulonephritis in the immunized rabbits appears to depend upon two factors: (a) the amount of autoantikidney antibody made to the common renal antigens; and (b) the quantity of the common antigens available in the host's kidneys. An amount of common antigen sufficient to fix a nephritogenic amount of antibody is essential for the development of disease.  相似文献   
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