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The use of capnography has expanded over recent years. Currently, capnography is used in a variety of acute care settings. This article describes what capnography is and how it is used. The normal and abnormal capnogram or waveforms are described to assist in identifying various clinical situations. The multiplicity of clinical indications include detection of pulmonary embolism as well as malpositioned endotracheal/tracheal, gastric, and small bowel tubes. Capnography also provides clinicians with information regarding expiratory breathing patterns and assists in perfusion assessments such as those for cardiopulmonary resuscitation. Finally, case studies are provided to help the reader apply the concepts of capnography to a variety of acute care settings.  相似文献   
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Hypothyroidism is very often associated with cardiovascular diseases and neurological complications. Recently, homocysteine has been studied as an independent risk factor for atherosclerosis which negatively affects vascular endothelial cells. Because homocysteine metabolism is related to thyroid and steroid hormones, we studied these relationships in severe hypothyroidism and in euthyroid state. Homocysteine, testosterone and allopregnanolone concentrations were measured in the fasting plasma from 16 women who underwent total thyroidectomy, and who were either hypothyroid or euthyroid. Although all women used oral contraceptives, they were not protected against hyperhomocysteinemia during hypothyroid state. With the normalization of thyroid hormone concentrations homocysteine levels decreased to normal levels. There was a positive correlation between testosterone and homocysteine in the euthyroid state which suggests that not only estrogens but also androgen state should be considered in future studies on homocysteine.  相似文献   
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Disruption of genomic integrity due to deficient DNA repair capacity and telomere shortening constitute hallmarks of malignant diseases. Incomplete or deficient repair of DNA double‐strand breaks (DSB) is manifested by chromosomal aberrations and their frequency reflects inter‐individual differences of response to exposure to mutagenic compounds. In this study, we investigated chromosomal integrity in peripheral blood lymphocytes (PBL) from newly diagnosed cancer patients, including 47 breast (BC) and 44 colorectal cancer (CRC) patients and 90 matched healthy controls. Mutagen sensitivity was evaluated by measuring chromatid breaks (CTAs) induced by bleomycin and supplemented by the chemiluminescent measurement of γ‐H2AX phosphorylation in 19 cancer patients (11 BC, 8 CRC). Relative telomere length (RTL) was determined in 22 BC, 32 CRC, and 64 controls. We observed statistically significant increased level of CTAs (P = .03) and increased percentage of aberrant cells (ACs) with CTAs (P = .05) in CRC patients compared with controls after bleomycin treatment. No differences were observed between BC cases and corresponding controls. CRC and BC patients with shorter RTL (below median) exhibited significantly higher amount of ACs (P = .02), CTAs (P = .02), and cells with high frequency of CTAs (≥12 CTAs/PBL; P = .03) after bleomycin treatment. No such associations were observed in healthy controls. γ‐H2AX phosphorylation after bleomycin treatment in PBL did not differ between CRC and BC patients. Our results suggest that altered DSB repair measured by sensitivity towards mutagen in PBL occurs particularly in CRC carcinogenesis. Irrespective of cancer type, telomere shortening may be associated with a decreased capacity to repair DSB.  相似文献   
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ObjectiveThe aim of the study is to compare the course and severity of narcolepsy in relation to different ages at the disease onset.MethodsClinical interviews with the completion of the Stanford questionnaire, Epworth Sleepiness Scale (ESS) and Multiple Sleep Latency Test (MSLT) were evaluated in 105 patients (44 males, 61 females, mean age 45.4 ± 19.2, BMI 29.2 ± 5.8) suffering from narcolepsy.ResultsThe severity of the disease was judged by clinical complaints, ESS value and MSLT results. No relations with the age at onset and clinical tetrad were found, however, smoking may be associated with an increased risk of hypnagogic hallucinations. There was no correlation between the number of sleep and cataplectic attacks and the age at onset, nor did subjective ESS show any significant dependence. However, earlier onset of the disease correlated with shorter MSLT mean latency. A correlation was found between the BMI and narcolepsy sleepiness rating in the elderly and between degree of education attained and subjective complaints.ConclusionsThe clinical severity of narcolepsy does not depend on the age at onset.  相似文献   
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OBJECTIVE: As a standard method, periodic limb movements in sleep (PLMS) are detected by means of polysomnography (PSG). Actigraphic detection of PLMS is a recently developed method for performing of multiple-night recordings in an outpatient setting. The aim of our study was to assess sensitivity-related parameters of actigraphic detection of PLMS in comparison to the PSG, when mounted at ankles and at the base of the big toe. METHODS: We simultaneously performed PSG and actigraphic recordings at both ankles and at the bases of both big toes (Cambridge Actiwatch AW-64) for 40 nights. The PLM index (PLMI), number of periodic movements per hour of sleep, was the primary output of both methods. RESULTS: We have proven significant correlation of all resulting parameters when comparing actigraphy at either position to the PSG; however, the PLMI values obtained by the actigraphy at toes were significantly higher than by PSG (sign test, p<0.0001). At bases of the big toes, threshold of PLMI=7.6 was used as a cut off for positivity, while PLMI=5 at ankles was used for PSG. Comparing ankle versus toe actigraphic placement, sensitivity was 67% versus 94%, specificity was 95% versus 91% and negative predictive value was 78% versus 95%. The correlation of the results from actigraphy and PSG was not affected by presence of respiratory events. DISCUSSION: Our results suggest good validity of actigraphic PLM evaluation at the base of big toe using AW-64 devices and therefore, actigraphy seems suitable for screening purposes in both clinical and research usage.  相似文献   
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