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目的 研究新型磷酸二酯酶 (PDE) 3抑制剂西洛他唑(cilostazol)对中性粒细胞超氧自由基 (O·2 )和钙离子浓度([Ca2 + ]i)的影响。方法 体外培养急性早幼粒细胞白血病HL 6 0细胞 ,以 1 3%DMSO分化诱导为中性粒细胞样细胞后 ,采用特制新型仪器 ,同时实现化学发光法测定O·2 和荧光法测定 [Ca2 + ]i,观察西洛他唑对趋化肽N 甲酰 甲硫氨酰 亮氨酰苯丙氨酸 (fMLP)刺激引起的中性粒细胞样HL 6 0细胞O·2 生成和 [Ca2 + ]i 升高的影响以及二者变化的时相关系。结果 西洛他唑 (1~ 30 μmol·L-1)明显抑制由fMLP诱导的中性粒细胞O·2 生成和 [Ca2 + ]i 升高 ,其中 10和 30 μmol·L-1浓度的西洛他唑组与对照组相比差异有统计学意义 (P<0 0 1)。在时相关系上 ,fMLP诱导O·2 生成的达峰时间较之 [Ca2 + ]i 的变化略显滞后 ,而 10 μmol·L-1西洛他唑对fMLP诱导O·2 生成和 [Ca2 + ]i 升高的影响表现出一致性 ,几乎同步。结论 西洛他唑对fMLP 诱导的中性粒细胞样细胞内O·2 生成和 [Ca2 + ]i 具有同步的抑制作用 ,提示该药的药理学作用部分是通过影响中性粒细胞功能而实现的  相似文献   
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BACKGROUND: Image quality of the prior autofluorescence (AF) imaging systems, including the fiber-optic endoscope, was not feasible for general clinical use. The use of AF image alone resulted in low specificity. The objective of the study was to evaluate the resolution and the sensitivity of the novel videoendoscopy system by using AF and reflectance imaging (AFI) in the diagnosis of early esophagogastric cancers. METHODS: This was a case series study. The setting was a pretreatment examination at a cancer center. Five patients with superficial esophageal cancers (SEC) and 21 patients with 22 early gastric cancers (EGC) were included in the study. The extent of the tumors was diagnosed by white light (WL), AF and chromoendoscopic observations. The main outcome measurement was the diagnostic accuracy of each observation in relation to the histologic mapping as a criterion standard. RESULTS: Two of 5 SECs (40%) were correctly diagnosed in the WL image and all (100%) in the AF image as purple or magenta color in a green background. EGCs in atrophic mucosa were observed as purple or magenta areas in a green background, while diffuse-type EGCs in fundic mucosa were observed as green areas in a purple background. Of the 22 EGCs, diagnostic accuracy of WL, AF, and chromoendoscopic observations were 36%: 95% CI [16%, 56%], 68%: 95% CI [49%, 88%], and 91%: 95% CI [79%, 100%], respectively. AFI could reveal flat or isochromatic extensions that were not detected in the WL images. The limitations of the study were ulcerations or inflammation that caused overdiagnosis in the AF observation. CONCLUSIONS: The resolution of the AFI at present is limited, but the image quality was acceptable. The current system of AFI does not equal to chromoendoscopy in sensitivity but has an advantage over standard WL videoendoscopy.  相似文献   
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Rationale:Complement deficiency are known to be predisposed to disseminated gonococcal infection (DGI). We herein present a case of DGI involving a Japanese man who latently had a complement 7 deficiency with compound heterozygous variants.Patient concerns:A previously healthy 51-year-old Japanese man complained of sudden-onset high fever. Physical examination revealed various skin lesions including red papules on his trunk and extremities, an impetigo-like pustule on left forearm, and tendinitis of his right forefinger.Diagnosis:Blood culture testing detected gram-negative cocci, which was confirmed to be Neisseria gonorrhoeae based on mass spectrometry and a pathogen-specific PCR test.Interventions:Screening tests for underlying immunocompromised factors uncovered that complement activities (CH50) was undetectable. With a suspicion of a congenital complement deficiency, genetic analysis revealed rare single nucleotide variants in complement 7 (C7), including c.281-1G>T and a novel variant c.1454C>T (p.A485V). CH50 was normally recovered by adding purified human C7 to the patient''s serum, supporting that the patient has C7 deficiency with compound heterozygous variants.Outcomes:Under a diagnosis of DGI, the patient underwent an antibiotic treatment with cefotaxime for a week and was discharged without any sequela.Lessons:DGI is a rare sexually-transmitted infection that potentially induces systemic complications. Complement immunity usually defeats N. gonorrhoeae and prevents the organism from causing DGI. This case highlighted the importance of suspecting a complement deficiency when a person develops DGI.  相似文献   
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Introduction

A growing number of patients with obstructive colorectal cancer are being treated with self‐expanding metallic stents (SEMS) followed by laparoscopic resection. The aim of this study was to assess the feasibility of stent insertion and laparoscopic surgery for obstructive colorectal cancer and to compare these outcomes to regular laparoscopic surgery for non‐obstructive colorectal cancer.

Methods

We retrospectively analyzed the outcomes of patients with a malignant colonic obstruction who underwent SEMS placement followed by elective laparoscopic resection. The comparison was made between stent‐laparoscopy and laparoscopy alone for non‐obstructive colorectal cancer.

Results

Colonic stenting as a bridge to surgery was successful in 97.1% of all cases. Fifteen patients underwent an elective laparoscopic surgery for left‐sided colon and rectal cancer after SEMS. The mean interval from SEMS insertion to laparoscopic surgery was 21.5 days. There was no conversion to open surgery and no need for a diverting stoma. One patient (6.7%) experienced paralytic ileus. Our comparison of stent‐laparoscopy to regular laparoscopy for non‐obstructive colorectal cancer treatment showed comparable short‐term postoperative outcomes with the exception of blood loss, which was greater in the stent‐laparoscopy group.

Conclusion

Elective laparoscopic surgery after colonic stenting is a safe and feasible strategy for the treatment of an acute malignant colonic obstruction.  相似文献   
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Gefitinib blocks epidermal growth factor receptor autophosphorylation and subsequently the signal transduction pathways implicated in proliferation, metastasis, invasion, and angiogenesis. Reported adverse reactions to gefitinib include liver injury that is not fully understood. Liver injury was observed in 5 (12.2%) of 41 patients with non-small cell lung cancer who received gefinitib monotherapy. Onset of liver injury was seen between 28 and 56 days after initiation of administration. Two patients had Grade 2 liver injury and 3 patients, Grade 3. In 4 patients, liver injury was temporary, lasting during a period of continuous gefitinib administration. In another patient, gefitinib was discontinued because of the onset of liver injury, which improved when gefitinib administration was restarted. Gefitinib is necessary in most patients whose lung cancer is refractory to cytotoxic chemotherapy, because no other treatment regimens are available at present. The rate of liver injury in cases treated with gefitinib is high, and so it is necessary to observe liver function carefully, but the liver injury due to this drug is often transient. However, the use of gefitinib in many cases appears to be a necessity.  相似文献   
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