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1.
目的:观察非程控降温、-80℃冻存的方法对自体外周血十细胞(APBSC)的保存效果。方法:以6%羟乙基淀粉(HES)、5%二甲基亚砜(DMSO)及4%人血白蛋白(ALB)的混合物为冷冻防护剂,将APBSC直接置于-80℃下保存,冻存前反复苏后测定APBSC的CFU-GM、BFU-E;观察移植后造血功能重建情况。结果:13例患者白细胞在十3~+7天下降至(0.0~0.1)×10/L,白细胞(0.0~0.2)×109/L持续时间3~6天,于+9~+11天恢复至1.0X109/L以上.中性粒细胞绝对值(ANC)于+9~+11天达到0.5X109/L。血小板在+3~+7天下降至(2.0~21)×109/L,于+8~+15天恢复至20×109/L以上。CFU-GM、BFU-E回大率分别为76.5%、78.4%。结论:非程控降温、-80℃冻存是一简便、经济、有效的自体外周血于细胞保存方法。  相似文献   
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There is no universally accepted method to determine effective therapy for central sleep apnea (CSA). Continuous positive airway pressure (CPAP) applied acutely most often does not eliminate apneas and hypopneas. We hypothesized that the application of two or more therapeutic modalities after the diagnostic phase of polysomnography, a multi-modality titration study (MMTS), would identify a successful CSA treatment more often than a standard split-night study (SNS) and obviate the need for additional polysomnograms to determine a successful therapy. We retrospectively analyzed polysomnograms of patients diagnosed with CSA at our Sleep Disorders Center. We defined a therapy trial that resulted in an apnea–hypopnea index < 10 with at least one treatment modality as a therapeutic success. One hundred fifteen patients with CSA were studied. Sixty-six patients (57.4%) underwent a SNS, and 49 patients (42.6%) underwent a MMTS. SNS yielded only 8/66 (12.1%) successes on the first night, whereas a MMTS yielded 19/49 (38.8%) successes (p = 0.001, two-tailed Fishers exact). Patients who underwent a SNS eventually had similar rate of success as patients studied with MMTS (60.6 vs 63.3%, NS), but required more testing. Adaptive servo-ventilation was the most successful modality tested, yielding 36/46 (78.3%) successes. Trials of additional modalities following a failed trial of CPAP often produce a successful option that may guide therapy in patients with CSA. This approach may lead to establishing the diagnosis and treatment plans faster, while reducing unnecessary testing.  相似文献   
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A survey of bacteria contamination of hospital staff apparel in use in Anambra State, Nigeria, was carried out to determine the extent of contamination by clinically important bacteria. Of a total of 125 swab samples of hospital staff apparel, 72 (58%) showed bacterial contamination including 32 (70%) of 46 samples from hand gloves, 28 of 45 (62%) samples from protective gowns, and 12 of 34 (35%) samples from face-shields. The potentially pathogenic bacteria isolated were Salmonella spp, Proteus vulgaris, Shigella dysenteriae, Pseudomonas aeruginosa and Staphylococcus aureus. The isolation of clinically important bacteria from the apparel suggests the need for improved infection control measures.  相似文献   
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Recent data suggest that fibronectin may favor Staphylococcus aureus infection by promoting attachment to either injured tissues or implanted foreign bodies. We studied the quantitative adsorption of fibronectin onto polymethylmethacrylate (PMMA) cover slips by using a 125I-labeled preparation of the purified plasma glycoprotein. Fibronectin in buffer solutions showed a high affinity to PMMA coverslips. Adherence of S. aureus Wood 46 was studied on PMMA pre-exposed to fibronectin, using an assay specifically adapted to the cover slip model. Whereas S. aureus adherence in an albumin-containing buffer was less than or equal to 10(3) CFU on control uncoated cover slips, adherence in the same medium increased up to maximum of 7.7 X 10(4) CFU on cover slips preincubated in a solution of fibronectin (125-micrograms/ml). At intermediate fibronectin concentrations, bacterial adherence was a linear function of both the quantity in solution and of the quantity adsorbed on the PMMA cover slips. The presence of human serum proteins, as represented by a fibronectin-depleted pool, essentially prevented adsorption of radiolabeled fibronectin on PMMA and subsequent bacterial adherence on the cover slips. Precoating of PMMA with denatured collagen resulted in increased fibronectin adsorption on PMMA, even in the presence of serum proteins, and S. aureus adherence was optimal on such surfaces. Collagen may therefore play a role as a cofactor contributing to S. aureus adherence onto fibronectin-coated substrata or foreign bodies.  相似文献   
8.
These practice parameters are an update of the previously-published recommendations regarding the indications for polysomnography and related procedures in the diagnosis of sleep disorders. Diagnostic categories include the following: sleep related breathing disorders, other respiratory disorders, narcolepsy, parasomnias, sleep related seizure disorders, restless legs syndrome, periodic limb movement sleep disorder, depression with insomnia, and circadian rhythm sleep disorders. Polysomnography is routinely indicated for the diagnosis of sleep related breathing disorders; for continuous positive airway pressure (CPAP) titration in patients with sleep related breathing disorders; for the assessment of treatment results in some cases; with a multiple sleep latency test in the evaluation of suspected narcolepsy; in evaluating sleep related behaviors that are violent or otherwise potentially injurious to the patient or others; and in certain atypical or unusual parasomnias. Polysomnography may be indicated in patients with neuromuscular disorders and sleep related symptoms; to assist in the diagnosis of paroxysmal arousals or other sleep disruptions thought to be seizure related; in a presumed parasomnia or sleep related seizure disorder that does not respond to conventional therapy; or when there is a strong clinical suspicion of periodic limb movement sleep disorder. Polysomnography is not routinely indicated to diagnose chronic lung disease; in cases of typical, uncomplicated, and noninjurious parasomnias when the diagnosis is clearly delineated; for patients with seizures who have no specific complaints consistent with a sleep disorder; to diagnose or treat restless legs syndrome; for the diagnosis of circadian rhythm sleep disorders; or to establish a diagnosis of depression.  相似文献   
9.
目的:研究大鼠急性肺栓塞模型肺组织中衰老标记蛋白质30(SMP-30)的表达变化及其对Fas诱导的细胞凋亡的影响。方法:建立大鼠急性肺栓塞模型,分别在急性肺栓塞后1、8、24和48 h进行支气管肺泡灌洗,然后开胸取出肺组织。常规提取肺组织的总RNA和总蛋白,以正常组为对照,采取半定量RT-PCR的方法研究SMP-30在mRNA水平表达的变化;采用Western blotting方法进一步验证SMP-30在蛋白水平表达的变化;采用免疫组织化学方法检测大鼠肺组织中SMP-30以及肺泡巨噬细胞中IL-8在肺栓塞前后表达的变化及其组织分布情况;采用TUNEL法研究急性肺栓塞后组织细胞的凋亡情况;最后采用ELISA法检测急性肺栓塞后肺泡灌洗液中sFasL的浓度变化。结果:在大鼠急性肺栓塞后的不同时点,SMP-30的mRNA水平和蛋白水平均逐渐降低,在24和48 h下降最为明显。免疫组化研究表明SMP-30主要分布在支气管黏膜上皮细胞和肺泡上皮细胞,急性肺栓塞后SMP-30在上述细胞内的表达均明显降低。TUNEL染色发现随着SMP-30表达的降低,肺组织内出现明显的细胞凋亡现象,同时肺泡灌洗液中sFasL的浓度升高,肺泡巨噬细胞内IL-8的表达也明显升高。结论:大鼠急性肺栓塞后肺组织内SMP-30的表达明显降低,可能促进Fas-FasL细胞凋亡系统的活化。  相似文献   
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Candida albicans is an increasingly important fungal pathogen. Alveolar macrophages respond to fungal components such as zymosan by releasing arachidonic acid (AA) and AA metabolites. However, few studies hypothesized that macrophages respond to C. albicans by releasing AA and generating AA metabolites as a consequence of interaction of mannose and beta-glucan receptors with fungal cell wall components. [14C]AA-labeled rabbit alveolar macrophages released AA following stimulation with either live or heat-killed C. albicans. High-pressure liquid chromatography analysis revealed that 55% of the AA released was metabolized via cyclooxygenase and lipoxygenase pathways. The metabolites consisted of prostaglandin E2, prostaglandin F2 alpha, 6-ketoprostaglandin F1 alpha, thromboxane B2, and leukotrienes B4 and D4. We further examined the roles of alpha-mannan and beta-glucan components of C. albicans in mediating these alterations of eicosanoid metabolism. Prior work in our laboratory has shown that soluble alpha-mannan and beta-glucan inhibit macrophage mannose and beta-glucan receptors, respectively. Incubation of alveolar macrophages with soluble alpha-mannan derived from C. albicans (1 mg/ml) resulted in 49.8% +/- 2.6% inhibition of macrophage AA release during stimulation with intact C. albicans (P = 0.0001 versus control). Macrophage AA release in response to C. albicans was also inhibited to a significant but lesser degree by soluble beta-glucan (36.2% +/- 1.3%; P = 0.008 versus control). These results indicate that C. albicans stimulates macrophage AA metabolism and that these effects are partly mediated by alpha-mannan and beta-glucan constituents of the fungus.  相似文献   
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