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41.
目的 探讨芪苈强心胶囊联合尼可地尔对射血分数保留性心力衰竭患者心功能及细胞因子的影响。方法 连续入选2019年10月至2020年10月诊断为射血分数保留性心力衰竭的患者共90例,随机分为观察组(45例)与对照组(45例)。对照组给予常规抗心力衰竭药物加芪苈强心胶囊治疗,观察组在对照组治疗基础上,加用尼可地尔治疗。比较两组患者一般临床资料、细胞因子水平、心功能各项指标。随访1年患者心功能情况、细胞因子水平以及不良心脑血管事件(MACCEs)发生情况。结果 两组患者接受治疗1年后脑钠肽(BNP)、左室舒张末期内径、白细胞介素(IL)-1β、IL-6、肿瘤坏死因子-α(TNF-α)均降低,射血分数(EF)值较治疗前升高,差异有统计学意义(P<0.05)。组间对比发现,两组患者入院时基础BNP、细胞因子、超声心能指标(LVEF、左室舒张末期内径、左房内径)差异无统计学意义(P>0.05);接受治疗1年后观察组IL-1β、IL-6、TNF-α、BNP、左室舒张末期内径低于对照组,EF值高于对照组,差异有统计学意义(P<0.05)。随访1年对照组共有7例发生终点事件,观察组共有4...  相似文献   
42.
In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test.  相似文献   
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44.
Computer simulations of pedaling have shown that a wide range of pedaling tasks can be performed if each limb has the capability of executing six biomechanical functions, which are arranged into three pairs of alternating antagonistic functions. An Ext/Flex pair accelerates the limb into extension or flexion, a Plant/Dorsi pair accelerates the foot into plantarflexion or dorsiflexion, and an Ant/Post pair accelerates the foot anteriorly or posteriorly relative to the pelvis. Because each biomechanical function (i.e., Ext, Flex, Plant, Dorsi, Ant, or Post) contributes to crank propulsion during a specific region in the cycle, phasing of a muscle is hypothesized to be a consequence of its ability to contribute to one or more of the biomechanical functions. Analysis of electromyogram (EMG) patterns has shown that this biomechanical framework assists in the interpretation of muscle activity in healthy and hemiparetic subjects during forward pedaling. Simulations show that backward pedaling can be produced with a phase shift of 180 degrees in the Ant/Post pair. No phase shifts in the Ext/Flex and Plant/Dorsi pairs are then necessary. To further test whether this simple yet biomechanically viable strategy may be used by the nervous system, EMGs from 7 muscles in 16 subjects were measured during backward as well as forward pedaling. As predicted, phasing in vastus medialis (VM), tibialis anterior (TA), medial gastrocnemius (MG), and soleus (SL) were unaffected by pedaling direction, with VM and SL contributing to Ext, MG to Plant, and TA to Dorsi. In contrast, phasing in biceps femoris (BF) and semimembranosus (SM) were affected by pedaling direction, as predicted, compatible with their contribution to the directionally sensitive Post function. Phasing of rectus femoris (RF) was also affected by pedaling direction; however, its ability to contribute to the directionally sensitive Ant function may only be expressed in forward pedaling. RF also contributed significantly to the directionally insensitive Ext function in both forward and backward pedaling. Other muscles also appear to have contributed to more than one function, which was especially evident in backward pedaling (i.e. , BF, SM, MG, and TA to Flex). We conclude that the phasing of only the Ant and Post biomechanical functions are directionally sensitive. Further, we suggest that task-dependent modulation of the expression of the functions in the motor output provides this biomechanics-based neural control scheme with the capability to execute a variety of lower limb tasks, including walking.  相似文献   
45.
Nucleic acid sequence-based amplification (NASBA) is a technique that allows the rapid amplification of specific regions of nucleic acid obtained from a diverse range of sources. It is especially suitable for amplifying RNA sequences. A NASBA technique has been developed that allows the detection of avian influenza A subtype H5 from allantoic fluid harvested from inoculated chick embryos. The amplified viral RNA is detected by electrochemiluminescence. The NASBA technique described below is rapid and specific for the identification of influenza A subtype H5 viruses of the Eurasian lineage. More importantly, it can be used to distinguish highly pathogenic and low pathogenic strains of the H5 subtype.  相似文献   
46.
Five hundred allergy clinic patients were prick skin tested with papain, 1 mg/mL, in addition to usual local aeroallergens. Five of 475 subjects with seasonal allergic disease had positive skin tests to both papain and local pollens. None of the 25 individuals with negative skin test to pollens had skin reactivity to papain. The five subjects with positive skin tests to papain underwent double-blind placebo-papain challenges. All papain challenges were positive. Placebo challenges were negative. Papain-induced symptoms included palatal itching, watering itchy eyes, sneezing, rhinorrhea, abdominal cramps, diarrhea, and diaphoresis. Circulating papain-specific IgE was detected in all the papain-sensitive individuals, but not in control subjects. Confirmed papain sensitivity occurred in 1.05% of allergic subjects. In the papain-sensitive patients, cross-reacting antibodies with chymopapain were found. The small number of non-allergic subjects did not show any papain or chymopapain sensitivity in vitro.  相似文献   
47.
DNA studies of the translocation t(15;17) in acute promyelocytic leukemia (APL) have shown that the retinoic acid receptor alpha (RARA) gene on chromosome 17 is juxtaposed to the promyelocytic leukemia (PML) gene on chromosome 15. The PML breakpoints have been mapped to 3 clusters: bcr1, bcr2, and bcr3. We have examined the PML breakpoint distribution in a series of 33 Chinese patients with APL Twenty-two patients fell within bcr1, 2 within bcr2, and 9 within bcr3. The primary structure of the reciprocal chromosome translocation joints of one patient and that of their normal counterparts have been determined and compared to those of 2 previously reported cases. These studies revealed possible topoisomerase II cleavage sites close to the breakpoints and suggested implications of DNA attachment sites to nuclear matrix. We propose that these features are relevant to the process of illegitimate recombination generating the translocation. © 1993 Wiley-Liss, Inc.  相似文献   
48.
With the exception of signs of retraction and withdrawal, there have been few morphological data concerning degenerated neural profiles in adult motor endplates. Here, investigation into the ultrastructure of the soleus motor endplates of adult rats (4 months old) turned up particular axonal degeneration in approximately 3% of the subjects. These axons occur as synaptic debris in the synaptic matrix of the motor endplate, adjacent to thin processes of the perisynaptic cells occupying the outer most layer of the motor endplate and were devoid of basal lamina. They often possessed dense-cored vesicles (50-80 nm). Axonal debris released from Schwann cell processes occurred during the period of acute sciatic neurectomy, when nerve terminals progressively disrupted within the motor endplate associated Schwann cells. Finally, immunohistochemical staining for antibodies to label macrophages (ED1 or ED2) has shown that nerve fiber-associated macrophages are located near the motor endplate. The results suggest that during the course of endplate remodeling, a few parts of the terminal branches are disposed of through spontaneous collapse, subsequent release from the Schwann cell investment, and eventual ingestion by macrophages in the perisynaptic space.  相似文献   
49.
Mutations in the PKD1 gene are responsible for autosomal dominant polycystic kidney disease (ADPKD). Although PKD1 has been cloned and shown to be expressed at high levels in the fetal ureteric bud and ADPKD cystic epithelia in the human kidney, the function of its encoded protein, "polycystin-1" is unknown. In this study we used primary and immortalized human renal epithelial cell lines derived from normal fetal, adult, and ADPKD kidneys, that endogenously express PKD1, to study the biologic function of the polycystin-1 protein. ADPKD renal epithelial cells expressed high levels of polycystin-1 protein and showed increased adhesion to type I collagen by comparison with normal adult human renal epithelia that expressed little polycystin. Adherent ADPKD cells also expressed high levels of alpha2beta1-integrin and their attachment was inhibited by a functional monoclonal antibody to alpha2-integrin. Double labeling and confocal microscopy as well as coimmunoprecipitation analysis showed overlapping colocalization of polycystin-1 with alpha2beta1-integrin as well as with the focal adhesion proteins vinculin and paxillin in multiprotein clusters localized to focal areas of cell membrane contact with type I collagen matrix after short periods of attachment. Immunoprecipitation and Western immunoblot studies also showed that polycystin-1 was posttranslationally modified by tyrosine phosphorylation. These studies suggest that the PKD1-encoded protein is part of a large multiprotein complex in epithelial cells that functions in the regulation of extracellular matrix interactions with the plasma membrane and cell cytoskeleton.  相似文献   
50.
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