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71.
《Ultrastructural pathology》2013,37(4):307-313
We investigated the ultrastructural changes in the hematopoietic microenvironment of the bone marrow obtained from 15 untreated patients with chronic myelocytic leukemia (CML) in the chronic phase by transmission and scanning electron microscopy using the cryofracture technique. Examination of the unde-calcified bone marrow specimens confirmed extensive hyperplastic granulopoiesis. In the stroma, fat cells were scarce or absent. Macrophages were increased and scattered throughout the marrow. The cytoplasm contained abundant cellular debris and crystals of the Charcot-Ley den type. Slender reticular cells were inconspicuously located between proliferating myeloid cells. A few foci of fibrosis were occasionally observed. The sinus endothelium generally retained its continuity, and no features suggesting complete deterioration of the sinus were evident. However, certain alterations in the sinus wall were noted in the process of leukemia cell migration. Many cells migrated trans-cellularly into the circulation through transient large openings in the sinus endothelium. 相似文献
72.
目的:观察不同病程2型糖尿病(T2DM)患者甲襞微循环障碍程度。方法:600例住院T2DM患者,依病程分为新诊断组、3月~5年组、6年~10年组和>10年组。选取30例健康体检者为对照组。用徐州产HD-WX-10型微循环显微仪,在22~24℃室温下,检测所有对象的左手无名指,观察甲襞微循环形态、流态和袢周状态,并对各组加权积分值、不同程度异常率和部分指标异常进行统计学分析比较。结果:(1)不同病程各组T2DM患者甲襞微循环形态、流态和袢周状态积分均高于对照组,以管袢减少、白微栓、渗出和出血等改变较明显(P<0.01),中度异常患者比例较高。(2)病程10年以内各组患者积分值、部分指标异常率及异常程度无统计学差异(P>0.05)。(3)>10年组患者甲襞微循环流态及袢周形态积分和总积分较其它组增加(P<0.05),中度异常患者比例较高(P<0.01),管袢明显减少,白微栓和渗出显著增多(P<0.01)。结论:T2DM患者存在微循环障碍,病程>10年者较重。 相似文献
73.
74.
《Dental materials》2021,37(9):1416-1424
ObjectiveAim of this study was to evaluate the biocompatibility of four experimental antiadhesive and antibacterial dental filling composites on human gingival fibroblasts (HGFs).MethodsFor these experimental resin composites a delivery system based on novel polymeric hollow beads, loaded with Tego Protect (Aa1), Dimethicone (Aa2), Irgasan (Ab1) and methacrylated polymerizable Irgasan (Ab2) as active agents was used. The cultured HGFs’ cell integrity, proliferation, viability, collagen synthesis and cytokine release were measured. For this purpose, human gingival fibroblasts were treated with eluates from all four composites and compared with an experimental standard composite (ST). Eluate extraction times 24 h and 168 h were chosen.ResultsStatistical analysis was conducted via a mixed model. Both antibacterial composites reduced proliferation, collagen and cytokine synthesis significantly (p < 0.05), increasing with time of elution. Ab1 did also have a damaging effect on the membrane and on cell viability.SignificanceOverall, it can be concluded that the antiadhesive composites showed clear advantages over the antibacterial composites in terms of biocompatibility. This study also continues to show the potential of the new poly-pore system, as it can be used for a variety of other applications in future composite mixtures. 相似文献
75.
76.
目的: 探讨正畸应力变化下牙龈组织α平滑肌肌动蛋白(α-SMA)、Ⅰ型及Ⅲ型胶原变化以及龈沟液基质金属蛋白酶2(MMP-2)、金属蛋白酶组织抑制因子2(TIMP-2)的表达。方法: 选取南昌大学附属口腔医院2018年4月—2019年4月收治的正畸患者74例,随机分为A组(24例,0 g力)、B组(25例,75 g力)、C组(25例,150 g力)3组。于加力0、4周采集患者部分牙龈组织,采用免疫组织化学染色法检测α-SMA、Ⅰ型及Ⅲ型胶原表达水平。在加力后0、2、4周收集龈沟液,采用酶联免疫吸附法检测MMP-2、TIMP-2表达水平。采用Spearman相关性分析不同正畸应力与α-SMA、Ⅰ型胶原、Ⅲ型胶原、MMP-2、TIMP-2表达水平的相关性。采用SPSS 19.0软件包对数据进行统计分析。结果: 加力2周及加力4周,3组患者龈沟液MMP-2、TIMP-2表达水平依次升高(P<0.05);加力4周后,3组患者牙龈组织中α-SMA、Ⅰ型及Ⅲ型胶原水平依次升高(P<0.05);不同正畸应力与MMP-2、TIMP-2、α-SMA、Ⅰ型胶原及Ⅲ型胶原表达水平均呈正相关(P<0.05)。结论: 龈沟液TIMP-2、MMP-2表达水平以及肌成纤维细胞表达与正畸应力变化有关,可能在正畸治疗的牙周组织改建中发挥重要作用。 相似文献
77.
《Pediatric Dental Journal》2020,30(1):1-8
BackgroundThere is a tendency nowadays to encourage the use of natural substances in dentistry. Aloe vera is one of these substances, which has recently gained great importance in clinical research.ObjectivesTo evaluate the effectiveness of Aloe vera mouthwash in improving plaque, gingival and gingival bleeding indices in children.Materials and methodsThe study sample consisted of (17) children [age: (8) to (12) years]. The crossover design was applied, which means that the three types of mouthwashes (experimental “Aloe vera”, positive control “chlorhexidine”, and negative control “placebo”) would be used for all participants, with a washout period of (12) days. A special plaque guard was fabricated to facilitate localized plaque accumulation for (3) days. After that period, the mouthwashes were applied for (5) days. Plaque, gingival and gingival bleeding indices were studied before plaque accumulation (T0), after plaque accumulation (T1), and after applying the mouthwashes (T2). The values of plaque index (PI), gingival index (GI) and gingival bleeding index (GBI) were measured at each studied time point (T0, T1, and T2). Then, the differences between the values at the beginning of the use of each type of the mouthwashes and at the end of the period of there use were compared.ResultsThe results showed the efficacy of Aloe vera mouthwash in improving plaque, gingival and gingival bleeding indices, which was similar to chlorhexidine mouthwash effectiveness when both compared to the placebo mouthwash.ConclusionsThe use of Aloe vera mouthwash is effective in improving oral health and preventing gingivitis. 相似文献
78.
Drenjancevic-Peric I Greene AS Kunert MP Lombard JH 《Microcirculation (New York, N.Y. : 1994)》2004,11(8):669-677
OBJECTIVES: Angiotensin II suppression leads to impaired vascular relaxation in normotensive animals on a high-salt diet. The goal of this study was to determine whether normal vascular reactivity could be restored by transferring the chromosomal region carrying the Dahl salt-resistant (R) renin gene into the Dahl salt-sensitive (SS) genetic background in a strain of renin congenic rats (RGRR). METHODS: Male RGRR and SS rats were fed low-salt (0.4%) and high-salt (4%) diets for 4 weeks. The responses of cremaster muscle arterioles to acetylcholine (ACh), sodium nitroprusside (SNP), and elevated PO2 were assessed using video microscopy. RESULTS: ACh-induced dilation was significantly enhanced in RGRR on a high-salt diet compared to SS rats, while dilation to the NO donor SNP was similar in both strains. A high-salt diet significantly enhanced arteriolar constriction in response to elevated PO2, in both SS and RGRR rats. CONCLUSIONS: These data suggest that transfer of the chromosomal region containing the renin gene is crucial in the recovery of ACh-induced dilation of arterioles in RGRR rats vs. SS rats, and that factors in the SS genetic background contribute to an enhanced sensitivity to elevated PO2, independent of genes on chromosome 13. 相似文献
79.
Sangeeta Patankar Poornima Venkatraman Gokul Sridharan Shubhada Kane 《World Journal of Clinical Cases》2015,3(12):1011-1016
Burkitt's lymphoma(BL) is an aggressive form of nonHodgkin's B-cell lymphoma with three variants namely endemic, sporadic, and immunodeficiency-associated types. It is endemic in Africa and sporadic in other parts of the world. While the endemic form is widely reported to occur in early childhood and commonly involves the jaw bones, the sporadic form typically presents as an abdominal mass. This presentation reports a rare case of sporadic form of BL clinically manifesting as a generalized gingival enlargement in an immunocompetent adult male which demonstrated an aggressive behavior. The patient reported with a prominent anterior gingival swelling of 6 mo duration which slowly enlarged in size and associated with multiple lymph node involvement. Microscopic examination of the lesion using H, E and immunohistochemical diagnosis confirmed the diagnosis as BL. The patient succumbed to the disease before any therapy could be instituted. Since a wide array of causes can be attributed to gingival enlargements, it is necessary to consider malignancies as one of the important differential diagnosis so as to facilitate the need for appropriate diagnosis and prompt treatment. 相似文献
80.
目的:评估上前牙区即刻种植联合即刻修复的软组织效果。方法上前牙区单牙即刻种植患者26例,微创拔牙后植入ZIMMER TSV种植体,获得良好初期稳定性并实施即刻修复,经过6~12个月骨结合和牙龈塑形后完成上部修复,观察负重6个月后牙龈组织情况。结果26例患者完成骨整合及最终修复,负重正常,无探诊出血、牙龈红肿,近中龈乳头、远中龈乳头及龈缘高度降低分别为(0.52±0.22) mm、(0.56±0.31) mm 和(0.71±0.34) mm,差异无统计学意义(F=1.297,P=0.29)。结论上前牙区单牙即刻种植联合即刻修复存在不同程度的软组织退缩。 相似文献