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1.
经脉包括经(气)络和血(脉)络,清代周学海《读医随笔》将气络末端称为"气之细络",脉络末端称为"血之细络"。心之气络涵盖心脏起搏与传导系统等广泛调控机制,心之脉络涵盖冠状动脉循环系统,心之气络与脉络相互协调,营卫相偕而行,共同维持心脏正常功能。各种致病因素导致营卫异常而发为心律失常,基于脉络学说营卫理论"损其心者,调其营卫"(《难经·十四难》)治疗原则指导心律失常辨证论治,同时充分结合现代致病因素和致病特点,分别选用调节卫气营血之方药,标本兼治,以期为临床诊疗提供有益借鉴。  相似文献   
2.
《Immunity》2022,55(7):1316-1326.e4
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3.
《Vaccine》2015,33(49):6977-6982
Heterosubtypic immunity is defined as immune-mediated (partial) protection against an influenza virus induced by an influenza virus of another subtype to which the host has not previously been exposed. This cross-protective effect has not yet been demonstrated to the newly emerging avian influenza A viruses of the H7N9 subtype. Here, we assessed the induction of protective immunity to these viruses by infection with A(H1N1)pdm09 virus in a newly developed guinea pig model. To this end, ten female 12–16 week old strain 2 guinea pigs were inoculated intratracheally with either A(H1N1)pdm09 influenza virus or PBS (unprimed controls) followed 4 weeks later with an A/H7N9 influenza virus challenge. Nasal swabs were taken daily and animals from both groups were sacrificed on days 2 and 7 post inoculation (p.i.) with A/H7N9 virus and full necropsies were performed.Nasal virus excretion persisted until day 7 in unprimed control animals, whereas only two out of seven H1N1pdm09-primed animals excreted virus via the nose. Infectious virus was recovered from nasal turbinates, trachea and lung of all animals at day 2 p.i., but titers were lower for H1N1pdm09-primed animals, especially in the nasal turbinates. By day 7 p.i., relatively high virus titers were found in the nasal turbinates of all unprimed control animals but infectious virus was isolated from the nose of only one of four H1N1pdm09-primed animals.Animals of both groups developed inflammation of variable severity in the entire respiratory tract. Viral antigen positive cells were demonstrated in the nasal epithelium of both groups at day 2. The bronchi(oli) and alveoli of unprimed animals showed a moderate to strong positive signal at day 2, whereas H1N1pdm09-primed animals showed only minimal positivity. By day 7, only viral antigen positive cells were found after H7N9 virus infection in the nasal turbinates and the lungs of unprimed controls. Thus infection with H1N1pdm09 virus induced partially protective heterosubtypic immunity to H7N9 virus in (isogenic) guinea pigs that could not be attributed to cross-reactive virus neutralizing antibodies.  相似文献   
4.
《Vaccine》2016,34(29):3396-3404
Francisella tularensis (Ft) is a Category A biothreat agent for which there currently is no FDA-approved vaccine. Thus, there is a substantial effort underway to develop an effective tularemia vaccine. While it is well established that gender can significantly impact susceptibility to primary infection, the impact of gender on vaccine efficacy is not well established. Thus, development of a successful vaccine against tularemia will require an understanding of the impact gender has on vaccine-induced protection against this organism. In this study, a role for gender in vaccine-induced protection following Ft challenge is identified for the first time. In the present study, mucosal vaccination with inactivated Ft (iFt) LVS elicited gender-based protection in C57BL/6Tac mice against respiratory challenge with Ft LVS. Specifically, vaccinated male mice were more susceptible to subsequent Ft LVS challenge. This increased susceptibility in male mice correlated with increased bacterial burden, increased tissue inflammation, and increased proinflammatory cytokine production late in post-challenge infection. In contrast, improved survival of iFt-vaccinated female mice correlated with reduced bacterial burden and enhanced levels of Ft-specific Abs in serum and broncho-alveolar lavage (BAL) fluid post-challenge. Furthermore, vaccination with a live attenuated vaccine consisting of an Ft LVS superoxide dismutase (SodB) mutant, which has proven efficacious against the highly virulent Ft SchuS4 strain, demonstrated similar gender bias in protection post-Ft SchuS4 challenge. Of particular significance is the fact that these are the first studies to demonstrate that gender differences impact disease outcome in the case of lethal respiratory tularemia following mucosal vaccination. In addition, these studies further emphasize the fact that gender differences must be a serious consideration in any future tularemia vaccine development studies.  相似文献   
5.
《Molecular therapy》2020,28(6):1432-1441
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6.
7.
《Vaccine》2020,38(51):8185-8193
BackgroundWhile administration of the measles-mumps-rubella (MMR-II®) vaccine has been effective at preventing rubella infection in the United States, the durability of humoral immunity to the rubella component of MMR vaccine has not been widely studied among older adolescents and adults.MethodsIn this longitudinal study, we sought to assess the durability of rubella virus (RV)-specific humoral immunity in a healthy population (n = 98) of adolescents and young adults at two timepoints: ~7 and ~17 years after two doses of MMR-II® vaccination. Levels of circulating antibodies specific to RV were measured by ELISA and an immune-colorimetric neutralization assay. RV-specific memory B cell responses were also measured by ELISpot.ResultsRubella-specific IgG antibody titers, neutralizing antibody titers, and memory B cell responses declined with increasing time since vaccination; however, these decreases were relatively moderate. Memory B cell responses exhibited a greater decline in men compared to women.ConclusionsCollectively, rubella-specific humoral immunity declines following vaccination, although subjects’ antibody titers remain well above the currently recognized threshold for protective immunity. Clinical correlates of protection based on neutralizing antibody titer and memory B cell ELISpot response should be defined.  相似文献   
8.
《Vaccine》2020,38(39):6141-6152
Influenza vaccination is considered the most valuable means to prevent and control seasonal influenza infections, which causes various clinical symptoms, ranging from mild cough and fever to even death. Among various influenza vaccine types, the inactivated subunit type is known to provide improved safety with reduced reactogenicity. However, there are some drawbacks associated with inactivated subunit type vaccines, with the main ones being its low immunogenicity and the induction of Th2-biased immune responses. In this study, we investigated the role of a single-stranded RNA (ssRNA) derived from the intergenic region in the internal ribosome entry site of the Cricket paralysis virus as an adjuvant rather than the universal vaccine for a seasonal inactivated subunit influenza vaccine. The ssRNA adjuvant stimulated not only well-balanced cellular (indicated by IgG2a, IFN-γ, IL-2, and TNF-α) and humoral (indicated by IgG1 and IL-4) immune responses but also a mucosal immune response (indicated by IgA), a key protector against respiratory virus infections. It also increases the HI titer, the surrogate marker of influenza vaccine efficacy. Furthermore, ssRNA adjuvant confers cross-protective immune responses against heterologous influenza virus infection while promoting enhanced viral clearance. Moreover, ssRNA adjuvant increases the number of memory CD4+ and CD8+ T cells, which can be expected to induce long-term immune responses. Therefore, this ssRNA-adjuvanted seasonal inactivated subunit influenza vaccine might be the best influenza vaccine generating robust humoral and cellular immune responses and conferring cross-protective and long-term immunity.  相似文献   
9.
OBJECTIVE: It is well documented that cardiopulmonary bypass (CPB) severely impairs cellular immunity. The objective of this study was to investigate the effect of prostaglandin E1 (PGE1) on cellular immunity after CPB. METHODS: Patients who underwent elective cardiac surgery were randomly divided into the PGE1 group (n=12) and the control group (n=12). In the PGE1 group, PGE1 was administered at 20 ng/kg/min from just after the induction of anesthesia to the end of surgery. Peripheral blood mononuclear cells (PBMCs) were taken before anesthesia and on postoperative days 1, 3 and 7 (POD 1, POD 3 and POD 7). Proliferation responses of T cells to phytohemagglutinin (PHA) and pure protein derivative (PPD) antigen were measured as indicators of cellular immunity. RESULTS: PGE1 significantly attenuated the impairment of both PHA and PPD response after cardiac surgery on POD 1 (PHA response, 30 +/- 21% vs. 53 +/- 32%, control vs. PGE, p=0.048; PPD response, 18 +/- 21% vs. 39 +/- 27%, control vs. PGE, p=0.046). The reduced glutathione content of PBMCs in the control group was significantly decreased on POD 1. CONCLUSION: PGE1 attenuated the impairment of cellular immunity after cardiac surgery with CPB by reducing oxidative stress on PBMCs.  相似文献   
10.
人参根总皂甙对热应激小鼠免疫功能保护作用的机制初探   总被引:1,自引:0,他引:1  
小鼠在45℃高温环境15 min.末梢血T淋巴细胞百分数和淋巴细胞占白细胞百分数均下降.血清皮质酮升高。应激前15 min lP人参根总皂甙(GRS)50、100 mg·kg~(-1)可防止末梢血T淋巴细胞百分数的降低,但不能抑制血清皮质酮的升高。GRS50mg·kg~(-1)ip可防止末梢血中淋巴细胞占白细胞百分数的降低。GRS50 mg·kg~(-1)、利血平0.5 mg·kg~(-1)或水杨酸毒扁豆碱0.3 mg·kg~(-1)ip均可消除热应激对小鼠迟发超敏反应的抑制作用。  相似文献   
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