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31.
OBJECTIVES: The effects of gender and age on human esophageal function is poorly defined. Our aim was to investigate the sensory perception and the biomechanical properties of the esophagus both at the smooth muscle and the striated muscle segments in age- and gender-matched healthy subjects. Eleven older individuals (five men and six women, aged 55-82 yr) and 11 younger healthy individuals (five male and six female, aged 22-45 yr) participated in this study. METHODS: Graded balloon distentions were performed at the striated muscle and the smooth muscle segments of the esophagus in a random order using impedance planimetry. Impedance planimetry facilitated simultaneous assessments of the biomechanical properties and sensory perception. RESULTS: We found that both at the striated and smooth muscle segments, the cross-sectional area, circumferential wall tension-strain relationship and the sensory thresholds were similar between men and women. In contrast, at both of these segments, the cross-sectional area was larger (p < 0.05), the circumferential wall tension-strain association had shifted significantly (p < 0.05) to the left (i.e., the wall was stiffer), and the median thresholds for discomfort and pain were higher (p < 0.05) in older subjects. The biomechanical properties and thresholds for sensory perception also varied between the two esophageal segments. CONCLUSIONS: Aging was associated with a larger lumen and a stiffer but less sensitive esophageal wall. Thus, aging but not gender may influence esophageal function.  相似文献   
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目的:研究尼古丁对人树突状细胞(DC)功能的影响及其与急性冠状动脉综合征(ACS)发病的关系.方法:观察体外尼古丁对DC功能的作用以及11例正常对照者(正常对照组)与45例ACS者(ACS组)发病时及戒烟后DC的功能状态.流式细胞仪检测DC CD86的表达;混合淋巴反应检测DC对T淋巴细胞的刺激作用;酶联免疫吸附法(ELISA)测定混合淋巴反应上清液中细胞因子水平.结果:与正常对照组比较,ACS时DC表面CD86的表达明显增高,对T淋巴细胞刺激的能力增强;致炎细胞因子分泌增多;DC CD86的表达与日吸烟量正相关(r=0.63,P<0.01);平均戒烟5个月后,DC功能接近正常;体外尼古丁亦能明显刺激DC的功能,呈浓度依赖性.结论:①ACS时DC明显激活;②戒烟后DC功能可迅速恢复;③尼古丁可能是ACS时DC激活的刺激因素之一.  相似文献   
34.
Microparticles (MPs) resulting from vesiculation of different cell types in Plasmodium falciparum infection correlate with the level of proinflammatory cytokine TNF that may thereby determine the disease severity. Using TruCount tube based flow cytometric method for the exact quantification of MP and enzyme linked immunosorbent assay for the measurement of TNF, we conducted a hospital based case control study on P. falciparum malaria patients to scrutinize and infer the link between the two. In 52 cerebral malaria (CM), 21 multi-organ-dysfunction (MOD), 12 non cerebral severe malaria (NCSM) and 43 uncomplicated malaria patients, the MP level was found to be significantly elevated in febrile malaria patients compared to healthy controls and a striking decrease in MP level was observed with the clearance of the P. falciparum infection in the patients upon follow-up. The lowering of the parasite density with the level of plasma TNF and the positive correlation of the cytokine with the cell derived MPs and negative correlation with the respective cell count in human malaria patients suggests that TNF may be a key stimulant to the cells resulting in the release of MPs in malaria infection.  相似文献   
35.
Aim: Localization of isolated clusters of anterior olfactory nucleus (AON) in a human olfactory bulb and tract. Materials and methods: This investigation was done on human olfactory bulbs and their tracts, collected from the freshly donated cadavers, before embalming, in the Department of Anatomy, IPGMER, Kolkata. H&E stained histological slides were prepared along the whole length of specimens and examined under a Leica DM 2000 microscope and with a Leica Quin image analyzer. Results: The anterior olfactory nucleus was detected in the form of a major cluster and in two smaller clusters of neurons. The major cluster was located at the caudal pole of the bulb and was composed of medium-sized triangular cells which had an average diameter of 13.92 ± 3.43 μm. Out of the two minor clusters, one was detected at the beginning and another at the middle of the olfactory tract. Here neurons were little larger in size and their diameter ranged approximately 15–17 μm. Olfactory striae also accommodated some neurons in a scattered manner. Conclusion: This observation will be helpful in exploration of the complex role of AON in the organization and function of the olfactory system and its clinical significance in human.  相似文献   
36.
Manchanda  Smita  Semalti  Kapil  Bhalla  Ashu Seith  Thakar  Alok  Sikka  Kapil  Verma  Hitesh 《Emergency radiology》2021,28(6):1063-1072
Emergency Radiology - COVID-19 patients have been found to have an increased incidence of superadded fungal infections because of multiple factors such as impaired cell-mediated immunity,...  相似文献   
37.

Objective:

To report changes in the cardiovascular management of fluid and inotropic resistant septic shock in children based on echocardiography.

Design:

Retrospective case series.

Setting:

Tertiary care Pediatric Intensive Care Unit (PICU), Chennai.

Patients:

Twenty-two patients with unresolved septic shock after 60 ml/kg fluid plus inotropic agents in the first hour.

Interventions:

Bedside echocardiography (echo) within 6 h of admission to the PICU.

Results:

Over a 28-month period, of 37 patients with septic shock, 22 children remained in shock despite 60 ml/kg fluid and dopamine and/or dobutamine infusions as per guidelines. On clinical exam, 12 patients had warm shock and ten had cold shock, however, six exhibited an unusual pattern of cold shock with wide pulse pressures on invasive arterial monitoring. The most common echocardiographic finding was uncorrected hypovolemia in 12/22 patient while ten patients had impaired left ± right ventricular function. Echocardiography permitted an appreciation of the underlying disordered pathophysiology and a rationale for adjustment of treatment. Shock resolved in 17 (77%) and 16 patients (73%) survived to discharge.

Conclusions:

Bedside echo provided crucial information that was not apparent on clinical assessment and affords a simple noninvasive tool to determine the cause of low cardiac output in patients who remain in shock despite 60 ml/kg fluid and inotropic support. Most patients in our series had vasodilatory shock with wide pulse pressures and most common finding on echo was uncorrected hypovolemia. The echo findings allowed adjustment of therapy which was not possible based on clinical examination alone.  相似文献   
38.

The persistence of residual infection is one of the major factors in failure of the Global Programme to Eliminate Lymphatic Filariasis (GPELF). The present study aims to explore the status of sheath antibody and regulatory T cells (Tregs) known to play key roles in clearance of parasite and patent filarial infection, in individuals with residual infection after MDA. A total of 61 microfilaremic (Mf) individuals were followed up after at least 6 rounds of MDA. Infection status of subjects was assessed through the detection of Mf and circulating filarial antigen (CFA). Antibodies to Mf sheath were determined by immuno-peroxidase assay (IPA). The expression of Tregs was measured by a flow cytometer. IL-10 and IFN-γ were evaluated using the commercially available ELISA kit. The sheath antibody was present in subjects who have cleared both Mf and CFA and absent in individuals who were found to be Mf /CFA positive. Further individuals carrying infection have significantly high levels of Tregs and IL-10. A positive correlation was observed between Tregs, IL-10, and CFA in infected individuals. In contrast, a negative correlation was observed between IFN-γ and IL-10 in both infected and uninfected subjects. Our study reveals that the absence of a sheath antibody and a high level of Tregs and IL-10 are the hallmarks of the persistence of residual filarial infection.

  相似文献   
39.
Corpus luteum rupture presenting as acute abdomen is an underdiagnosed condition. Though a self-limiting entity, its differentiation from other causes is essential to prevent unnecessary surgical procedures. The radiologist should be aware of the possibility of a ruptured haemorrhagic ovarian cyst in a female of reproductive age group presenting with pelvic pain and a large amount of haemorrhagic ascites. Imaging characteristically reveals a thick-walled cystic structure in the adnexa with internal echoes, focal discontinuity or irregularity of its wall with haemoperitoneum. While sonography is usually indicative of corpus luteum rupture, cross-sectional imaging (CT/MRI) can be used to confirm the diagnosis.  相似文献   
40.
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