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501.
502.
Background High resolution manometry (HRM) has demonstrated two distinct smooth muscle contraction segments in the esophageal body; changes in these segments typify certain esophageal disorders. We investigated segmental characteristics in subgroups of non‐cardiac chest pain (NCCP). Methods 32 NCCP subjects were segregated into a GERD group (ambulatory pH testing off antisecretory therapy showing elevated total acid exposure time, AET ≥ 4.0% and positive symptom association probability, SAP) and an acid sensitive group (normal AET and positive SAP). HRM Clouse plots were analyzed; smooth muscle segment lengths, pressure amplitude peaks were measured for segment 2 and segment 3 (proximal and distal smooth muscle segments). Pressure volumes were determined in mmHg cm?1 s?1 for each peristaltic segment, and ratios of segment 3 : segment 2 calculated. Values were compared to a cohort of 14 normal controls. Key Results A distinctive shift in peak contraction amplitude to segment 3 was evident in the acid sensitive group (segment 2, 100.03 ± 11.06 mmHg, segment 3, 145.23 ± 10.29 mmHg, P = 0.006). Pressure volumes were similarly shifted to segment 3 (segment 2: 855.3 ± 135.1 mmHg cm?1 s?1, segment 3: 2115.2 ± 218.6 mmHg cm?1 s?1, P < 0.005). In contrast, peak amplitude and pressure volume were near equal in the two segments in GERD and control groups. A threshold segment 3 : segment 2 pressure volume ratio of 1.9 had the best performance characteristic for segregating acid sensitivity subjects from all GERD and control subjects. Conclusions & Inferences Shift in contractile vigor to the third peristaltic segment may be seen in acid sensitive subjects. HRM characteristics of smooth muscle contraction segments are of value in making this determination.  相似文献   
503.
目的 探讨和研究微弹簧圈血管内栓塞难治性外伤性颈动脉海绵窦瘘的疗效.方法 回顾13例用微弹簧圈栓塞治疗的难治性外伤性颈动脉海绵窦瘘患者.所有患者均有持续性颅内血管杂音、搏动性突眼及球结膜充血水肿.均采用微弹簧圈栓塞治疗,其中经动脉入路9例,经眼上静脉入路4例.结果 12例术后造影瘘El消失且颈内动脉通畅.1例填人5枚微...  相似文献   
504.
Thirteen polymorphic tri- and tetra-nucleotide microsatellites are reported for the spotted snow skink (Niveoscincus ocellatus) from Tasmania. Variation was assessed among 40 individuals collected from a single locality. Most loci had 12–19 alleles, although one had more than 20 alleles, while observed heterozygosities ranged between 0.25 and 0.93. Eleven loci were also polymorphic in the congeneric species N. metallicus (N = 16 collected from a single locality).  相似文献   
505.

Background  

Asthma is the most common chronic disease in childhood, characterized by chronic airway inflammation. There are problems with the diagnosis of asthma in young children since the majority of the children with recurrent asthma-like symptoms is symptom free at 6 years, and does not have asthma. With the conventional diagnostic tools it is not possible to differentiate between preschool children with transient symptoms and children with asthma. The analysis of biomarkers of airway inflammation in exhaled breath is a non-invasive and promising technique to diagnose asthma and monitor inflammation in young children. Moreover, relatively new lung function tests (airway resistance using the interrupter technique) have become available for young children. The primary objective of the ADEM study (Asthma DEtection and Monitoring study), is to develop a non-invasive instrument for an early asthma diagnosis in young children, using exhaled inflammatory markers and early lung function measurements. In addition, aetiological factors, including gene polymorphisms and gene expression profiles, in relation to the development of asthma are studied.  相似文献   
506.
Background Multiple rapid swallows (MRS) inhibit esophageal peristalsis and lower esophageal sphincter (LES) tone; a rebound excitatory response then results in an exaggerated peristaltic sequence. Multiple rapid swallows responses are dependent on intact inhibitory and excitatory neural function and could vary by subtype in achalasia spectrum disorders. Methods Consecutive subjects with incomplete LES relaxation on high‐resolution manometry (HRM) (Sierra Scientific, Los Angeles, CA, USA) in the absence of mechanical obstruction were prospectively identified. Achalasia spectrum disorders were classified and HRM plots reviewed according to Chicago criteria. Esophageal peristaltic performance and LES function were assessed after 10 wet swallows and MRS (five 2 mL water swallows 2–3 s apart). Findings were compared with 18 healthy controls (28.5 ± 0.6 years, 44% women). Key Results A total of 46 subjects (57.1 ± 2.1 years, 52.2% women) met inclusion criteria. There was complete failure of peristalsis with MRS in all subjects with achalasia subtypes 1 and 2. In contrast, 80% of achalasia subtype 3 and incomplete LES relaxation (EGJ outflow obstruction) with preserved esophageal body peristalsis had a contractile response to MRS (P < 0.001 compared with subtypes 1 and 2); controls demonstrated 94.4% peristalsis. Percent decrease in LES residual pressure during MRS (compared to wet swallows) segregated achalasia subtypes; those with aperistalsis (subtypes 1 and 2) had a lesser decline (22.6%) compared to those with retained esophageal body peristalsis (40.5%) and controls (51.3%, P < 0.001 across groups). Conclusions & Inferences Multiple rapid swallow responses segregate achalasia spectrum disorders into two patterns differentiated by presence or absence of esophageal body contraction response to wet swallows. These findings support subtyping of achalasia, with pathophysiologic implications.  相似文献   
507.
508.
509.
Lyonia ovalifolia (angeri) is a deciduous tree whose shoot and leaves are toxic. Its chemical constituents include grayanane diterpenoids, lyoniol A, and other toxic compounds. Young children might consume it intentionally or unintentionally, with subsequent adverse health outcomes and even mortality depending on the amount ingested. We present a case of an adolescent girl who developed poisoning on ingestion of angeri leaves.  相似文献   
510.
Ataxia with vitamin E deficiency (AVED) is a rare cause of hereditary ataxia in developing countries with unknown prevalence. AVED is an autosomal‐recessive disorder, which is characterized by ataxia, areflexia, and proprioceptive and vibratory sensory loss. The disease is characterized clinically by symptoms with often resembling to those of Friedreich ataxia (FRDA). Vitamin E supplementation improves symptoms and prevents the progression of the disease. In this case report, we reviewed the recently updated findings in AVED in regard to the management and present a case of AVED in a 16‐year‐old boy, who was initially misdiagnosed as FRDA, prior to the genetic test.  相似文献   
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