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11.
This study investigates the effects of partial exhalation to feelings of anxiety. Thirty five volunteer subjects (14 male, 21 female, mean age 40.6) were first trained in slow diaphragmatic breathing (SDB). Then subjects rated their anxiety levels on a scale from 1 (none) to 5 (extreme) in sequential conditions of SDB, 70% subjective exhalation, and SDB. During the 70% subjective exhalation phase, subjects were instructed to breathe and limit their exhalation to 70% of the inhaled volume during each consecutive breath. The 70% subjective condition significantly (P<.0005) increased=" subjects'=" anxiety=" levels=" as=" compared=" to=" the=" initial=" sdb=" baseline,=" while=" a=" return=" to=" sdb=" significantly=" reduced=" the=" anxiety=" levels.=" the=" 70%=" approach=" appears=" useful=" in=" demonstrating=" to=" the=" client=" that=" possible=" changes=" in=" breathing=" patterns=" can=" affect=">We gratefully acknowledge the assistance of Richard Steiner, Ph.D. for his comments and help with the statistical analysis in this article. The preliminary findings of this article were presented at the Twenty-first Annual Meeting of the Association for Applied Psychophysiology and Biofeedback.  相似文献   
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13.
摘要 目的:分析乳腺癌根治术患者术前焦虑的影响因素,并探讨术前焦虑对患者术后恢复、细胞免疫功能和生命质量的影响。方法:选择我院2020年3月~2021年12月期间收治的拟行乳腺癌根治术的120例患者作为研究对象,术前1 d采用焦虑自评量表(SAS)评估所有患者的焦虑状况,根据是否存在焦虑分为焦虑组和无焦虑组,乳腺癌根治术患者术前焦虑的影响因素采用多因素Logistic回归分析。对比焦虑组和无焦虑组的术后恢复、细胞免疫功能和生命质量情况。结果:120例乳腺癌根治术患者中,有31例患者无术前焦虑,89例患者存在焦虑症状,根据是否存在术前焦虑分为焦虑组(n=89)和无焦虑组(n=31)。乳腺癌根治术患者术前焦虑与年龄、文化程度、家庭人均月收入、付费方式、婚姻状况、家庭支持、既往有无全麻史、术前住院时长、定期体检有关(P<0.05)。多因素Logistic回归分析结果表明:年龄<60岁、文化程度为小学及其以下、家庭人均月收入<3000元、婚姻状况为未婚、无家庭支持、既往无全麻史、术前住院时长>1 d是乳腺癌根治术患者术前焦虑的危险因素(P<0.05)。焦虑组的术后首次肛门排气时间、首次下床活动时间、术后住院时间均长于无焦虑组(P<0.05)。两组术后1个月CD3+、CD4+、CD4+/CD8+水平升高,且无焦虑组高于焦虑组(P<0.05),两组术后1个月CD8+水平下降,且无焦虑组低于焦虑组(P<0.05)。两组术后1个月生理状况、情感状况、社会/家庭状况、功能状况、附加关注评分和总分下降,且无焦虑组低于焦虑组(P<0.05)。结论:乳腺癌根治术患者术前焦虑发生率较高,其发生受到年龄、文化程度、家庭人均月收入、婚姻状况、家庭支持、既往有无全麻史、术前住院时长等多种因素的影响,可导致患者术后恢复时间延长,细胞免疫功能和生命质量降低。  相似文献   
14.
Up-to-date information on the prevalence and trends of common mental disorders is relevant to health care policy and planning, owing to the high burden associated with these disorders. In the first wave of the third Netherlands Mental Health Survey and Incidence Study (NEMESIS-3), a nationally representative sample was interviewed face-to-face from November 2019 to March 2022 (6,194 subjects; 1,576 interviewed before and 4,618 during the COVID-19 pandemic; age range: 18-75 years). A slightly modified version of the Composite International Diagnostic Interview 3.0 was used to assess DSM-IV and DSM-5 diagnoses. Trends in 12-month prevalence rates of DSM-IV mental disorders were examined by comparing these rates between NEMESIS-3 and NEMESIS-2 (6,646 subjects; age range: 18-64 years; interviewed from November 2007 to July 2009). Lifetime DSM-5 prevalence estimates in NEMESIS-3 were 28.6% for anxiety disorders, 27.6% for mood disorders, 16.7% for substance use disorders, and 3.6% for attention-deficit/hyperactivity disorder. Over the last 12 months, prevalence rates were 15.2%, 9.8%, 7.1%, and 3.2%, respectively. No differences in 12-month prevalence rates before vs. during the COVID-19 pandemic were found (26.7% pre-pandemic vs. 25.7% during the pandemic), even after controlling for differences in socio-demographic characteristics of the respondents interviewed in these two periods. This was the case for all four disorder categories. From 2007-2009 to 2019-2022, the 12-month prevalence rate of any DSM-IV disorder significantly increased from 17.4% to 26.1%. A stronger increase in prevalence was found for students, younger adults (18-34 years) and city dwellers. These data suggest that the prevalence of mental disorders has increased in the past decade, but this is not explained by the COVID-19 pandemic. The already high mental disorder risk of young adults has particularly further increased in recent years.  相似文献   
15.
A cell line (UM-BGE-2) derived from embryos of the cockroach Blattella germanica was frozen to ?196 °C under a variety of conditions and cell viability was assayed after warming. It was found that cell viability was affected by the cooling rate, the warming rate, the controlled cooling endpoint temperature, and the type and concentration of cryoprotectant. The best survival for cells suspended in Grace's tissue culture medium containing 1 M Me2SO was obtained when cells were cooled at 1 °C/ min to at least ?90 °C before being placed in liquid nitrogen and warmed at more than 900 °C/min. Cultures initiated from these frozen cells produce typical growth curves and appear normal after several passages.  相似文献   
16.
The interactions of cis- and trans-diammineplatinum compounds with 5′-GMP and 5′-dGMP in dilute aqueous solution at neutral pH were investigated by 1H nmr. In addition to the 1:2 Pt nucleotide complexes cis- and trans-Pt(NH3)2(GMP)2, it was possible to study the formation of the 1:1 Pt-nucleotide complexes with either one coordinated water or chloride ion. At 5°C GMP reacts with a stoichiometric amount of cis-diaquodiammine-platinum to yield cis-Pt(NH3)2(GMP) (H2O) as a sole reaction product. From the present results it is concluded that such a complex may play an important role as the initial reaction product between antitumor compounds like cis-Pt(NH3)2Cl2 and guanine in DNA in living organisms. The coupling constant 3J(H(1′)-H(2′)) of the H(1′) sugar proton in cis-Pt(NH3)2(GMP)2 is temperature dependent, indicating a conformational change in the sugar moiety.  相似文献   
17.
A thorough spectral investigation of the copper(II) complex of the antitumor compound, bleomycin, has been carried out in solution employing optical, difference optical, electron spin resonance, and circular dichroism techniques. The optical spectrum of a pH = 7 solution of the 1:1 complex between copper(II) and bleomycin is characterized by a broad weak band in the visible region (λmax = 610 nm) that cannot be resolved and intense ultraviolet bands at 317 (? = 2800), 327 (shoulder), 250 (? = 4700), and 257 nm (shoulder). The circular dichroism spectrum in the visible region shows the broad and weak visible absorption band contains at least three components (558, 675, and 880 nm) that are likely to be “d-d” in origin. The electron spin resonance spectrum is characteristic of a tetragonal d9 copper(II) system showing no rhombic distoritions at X-band frequencies (gx = gy ± 0.002). The spin Hamiltonian parameters for the pH = 7.0 solution corrected for second order effects are A = 177 × 10?4 cm?1, A ? 15 × 10?4 cm?1, g = 2.214, g = 2.039. Most interesting was the observation of extra hyperfine splitting due to endogenous nitrogen coordination in a 30% glycerol glass (AN = 12.0 × 10?4 cm?1). That pattern is best interpreted as a seven-line sequence associated with three liganded nitrogens. A dramatic change in all spectral properties occurs when the pH of the copper(II)-bleomycin complex is lowered to 2.5. All these data taken together suggest a CuN3O coordination complex in solution. Details and justifications as well as a discussion of the limitations of the interpretations are presented.  相似文献   
18.
Carbamate kinase from Streptococcus faecalis is inactivated by butanedione in borate buffer, which implies the presence of an essential arginine at the active site of the enzyme. The inactivation reaction is first order in [butanedione] and a replot of the inactivation rate data infers that one arginine is modified. The enzyme is protected against inactivation by ADP, ATP, the metal-nucleotides and carbamyl phosphate but not by carbamate. Amino acid analyses reveal that one of three arginines is modified by butanedione in the absence of protecting agents, and the binding of ADP to the enzyme prevents modification. Thus, analysis of the data suggest that (i) substrate binding to arginine and (ii) protein conformational changes at the active site are responsible for protection of an essential arginine against modification by butanedione.  相似文献   
19.
The ability of l-methionine to support glutathione biosynthesis has been investigated in isolated rat hepatocytes under conditions of normal and depleted glutathione status. The addition of l-[35S]methionine or [l-[35S]homocysteine to incubation media containing hepatocytes results in the incorporation of 35S into intracellular glutathione. Additionally both l-methionine and l-homocysteine are capable of supporting the resynthesis of glutathione in isolated hepatocytes after prior depletion with diethyl maleate. The inclusion in the incubation medium of 1 mm propargylglycine, which is an irreversible inhibitor of the terminal enzyme of the cystathionine pathway, substantially blocks the incorporation of 35S from methionine and l-homocysteine into cellular glutathione. Propargylglycine treatment of hepatocytes in the presence of [35S]methionine is shown to result in the intracellular accumulation of [35S]cystathionine. These results strongly support the conclusion that in rat hepatocytes the cystathionine pathway enables methionine to provide a significant source of l-cysteine for the support of glutathione biosynthesis, under both normal and glutathione-depleted conditions.  相似文献   
20.
H H Tai  B Yuan  M Sun 《Life sciences》1979,24(14):1275-1280
Renal, pulmonary and gastric NAD+-dependent 15-hydroxyprostaglandin dehydrogenase activities were determined in both spontaneously hypertensive and normotensive rats at 6 and 12 weeks of age. Renal enzyme activity in hypertensive rats was only 30–40% of that present in normotensive controls at both ages. In contract, pulmonary enzyme activity in hypertensive animals was twice as active as that in normal controls. There was no significant difference in gastric enzyme activity. NAD+-dependent 9-hydroxyprostaglandin dehydrogenase activity, the enzyme responsible for the conversion of vasoinactive PGF metabolites to PGE metabolites, also failed to show any difference in two types of rat kidneys. The results indicate that, in hypertension, prostaglandin inactivation is impaired in kidney but is facilitated in lung.  相似文献   
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