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41.
目的探讨胚胎发育中胎龄及胚体大小与胰岛细胞分化的相关性。方法收集妊娠6~14周的胚胎20例,测其重量,顶臀径并通过免疫组织化学染色观察胰高血糖素(glucagon)在胰岛细胞分化过程中的表达。结果妊娠9周左右,胚体重约2.89±0.12g,顶臀径约80.0±2.8mm,此时胰腺导管上皮细胞开始分化出胰岛细胞,并且具有内分泌功能。结论妊娠发育的胚胎在胎龄9w、顶臀径30mm、重量约为2.89g左右时,胰岛细胞开始从胰腺导管上皮细胞分化。  相似文献   
42.
目的:总结手术中发生医源性血管损伤的处理经验。方法:10例在外科手术中损伤血管的患者,其中门静脉,下腔静脉、髂总静脉损伤各2例,股总静脉、颈总动脉、腋静脉、腘动脉损伤各1例。行血管修补术5例,行端-端吻合术1例,自体静脉移植术1例,人工血管移植1例,钳夹止血1例,血管结扎1例。结果:本组痊愈8例;死亡2例,其中下腔静脉损伤止血失败死亡1例,颈总动脉损伤结扎死亡1例。结论:医源性血管损伤重在预防,一旦发生血管损伤,迅速有效地控制出血是手术成功的关键,血管修补或吻合术疗效良好。  相似文献   
43.
There were few studies of cumulative live birth rates (CLBRs) based on multicenter reproductive clinical data from the general Chinese population. Here we report a retrospective cohort study, including 14 311 women with 17 315 cycles, in three reproductive centers to evaluate two estimated parameters of CLBRs with multiple transfer cycles of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) in a Chinese population. We found that CLBRs were related to female age and endometrial thickness. By the fourth transfer cycle, the conservative and optimal estimates of CLBRs were 52.95% and 77.30% in women under 30 years of age, and 18.17% and 26.51% in those 37 years of age or older, respectively. The two estimates were 44.70% and 63.15% in women with endometrial thickness more than 7 mm, and 32.05% and 46.18% in those with less than 7 mm, respectively. In addition, body mass index (BMI), duration of infertility, and infertility diagnoses may also be related to CLBRs on certain conditions. The findings from this study on CLBRs after multiple transfer cycles of IVF/ICSI treatment on different conditions in the Chinese population should be beneficial to both infertile couples and clinicians.  相似文献   
44.
目的探析中高频听力下降型突发性聋采取耳后注射甲强龙治疗的临床效果及可行性。方法选取2019年5月~2020年7月本院耳鼻喉科就诊的中高频听力下降型突发性聋患者,共纳入病例54例,以随机法分组,即常规组(n=27)和观察组(n=27),常规组予常规治疗,观察组采取耳后注射甲强龙,比较两组效果。结果观察组有效率相比于常规组显著提高(P<0.05);治疗3周后,观察组2000~8000Hz频率听力提高值与常规组比(P<0.05)。结论中高频听力下降型突发性聋采取耳后注射甲强龙治疗效果理想,值得推广。  相似文献   
45.
目的 探讨引起新生儿锁骨骨折的产科相关因素。方法 对我院 1997年 1月~ 2 0 0 0年 12月新生儿锁骨骨折 4 1例进行回顾性分析。结果 新生儿锁骨骨折的发生率阴道难产高于阴道顺产 ,剖宫产中无新生儿锁骨骨折的发生。新生儿出生体重≥ 35 0 0g组锁骨骨折发生率较 <35 0 0g组高 (P <0 0 0 5 ) ,差异有显著性。产后常规的新生儿体验可早期发现新生儿锁骨骨折和及时处理。新生儿锁骨骨折的预后良好。结论 提高阴道助产技术 ,正确掌握分娩机转 ,可降低新生儿锁骨骨折的发生率。  相似文献   
46.
BACKGROUND:Tumor stem cells are the root of cancer recurrence and metastasis, so clinical researches should focus on the effects of different treatments on tumor stem cells. OBJECTIVE:To explore the effects of endocrine therapy and chemotherapy on stem cells in patients with breast cancer. METHODS:After recovery and cultivation of estrogen receptor-positive human breast cancer cell lines MCF-7, passage 3 cells in logarithmic phase were selected and divided into three groups containing control, estradiol and estradiol with tamoxifen groups. The estradiol group was divided into three subgroups: 10-7, 10-8 and 10-9 mol/L estradiol was added into the medium, respectively; the estradiol with tamoxifen group was divided into three subgroups: 10-7, 10-8 and 10-9 mol/L estradiol with 10-6 mol/L tamoxifen were added into the medium, respectively. The same amount of absolute ethyl ethanol was added into the medium of control group. Fifteen female patients with late recurrence and metastasis of breast cancer received chemotherapy as recurrence and metastasis group. Another 15 healthy volunteers were selected as healthy control group. RESULTS AND CONCLUSION:The proportion of CD44+CD24-/low cell subsets in the estradiol and estradiol with tamoxifen groups was significantly higher than that of the control group (P < 0.05), and the proportion of CD44+CD24-/low cell subsets in the estradiol group was significantly higher than that of the estradiol with tamoxifen group at the same concentration (P < 0.05). The proportion of CD44+CD24-/low cell subsets had no significant differences among groups at 10 and 20 days of culture (P < 0.05). The proportion of CD44+CD24-/low cell subsets significantly increased in MCF-7 cells after 24-hour intervention with different chemotherapy drugs. But only the proportion of CD44+CD24-/low cell subsets in the paclitaxel and doxorubicin groups was significantly higher than that of the control group after 20-day intervention (P < 0.05). Besides, the proportion of CD44+CD24-/low cell subsets in the peripheral blood of healthy volunteers was significantly lower than that of the recurrence and metastasis group (P < 0.05). Among 15 patients with late recurrence and metastatic of breast cancer, 9 had stable disease, 5 had partial remission, 1 had failed chemotherapy and cancer progression. Moreover, the proportion of CD45-CD44+CD24-/low cell subsets in the peripheral blood of patients sensitive for chemotherapy was significantly lower than that before treatment (P < 0.05). In conclusion, both endocrine therapy and chemotherapy exert a certain effect on the CD44+CD24-/low cell subsets of breast cancer positive for estrogen receptor. Given that CD44+CD24-/low cell subsets in MCF-7 cells resist chemotherapy drugs, the proportion of CD45-CD44+CD24-/low cells in the peripheral blood of patients sensitive for chemotherapy is decreased.  相似文献   
47.
目的探讨缺陷型、非缺陷型精神分裂症患者的认知功能的长期随诊特点。方法对1997年9月曾进行认知功能检查,持续住院的缺陷型22例和非缺陷型30例精神分裂症患者于4年后再次进行评定,同时采用简明精神病评定量表(BPRS)评定其症状。结果4年后精神分裂症患者仅非缺陷型的注意和计算明显降低,缺陷型患者的记忆因子明显降低外,其它各因子及总分无明显降低。结论精神分裂症患者的认知功能损害随病程进展并无明显加重趋势。  相似文献   
48.
目的 探讨肺毛细血管瘤病的临床病理特征,提高对其临床及病理改变的认识.方法 对2例肺毛细血管瘤病的临床资料和组织学形态进行回顾性分析,并采用组织化学染色和免疫组织化学染色(EnVision法)研究其形态和免疫表型特点.结果 患者主要临床表现为喘憋,影像学(CT及肺动脉造影)特点为双肺多发结节影,肺动脉增宽,组织学表现为灶状分布的肺问质和肺泡壁毛细血管增生,小动脉肌性化,免疫组织化学染色提示病灶中肥大细胞数量增多,血小板衍生生长因子受体(PDGFR)-β表达上调,Ki-67阳性指数小于1%,p53阴性.结论 肺毛细血管瘤病是一种肺毛细血管增生性疾病,其发病机制可能与肥大细胞数量和PDGFR-β上调有关.病理医师在肺毛细血管瘤病的正确诊断和治疗中起重要作用,应提高对该病的认识.  相似文献   
49.
目的观察视神经损伤后视神经和神经内毛细血管的超微结构变化,探讨视神经损伤的机制。方法建立家兔视神经损伤的动物模型,利用透射电子显微镜观察视神经及神经内毛细血管超微结构的变化。结果视神经损伤0.5h后,轴突部分肿胀,髓鞘疏松,微管、微丝排列出现紊乱,线粒体肿胀,毛细血管内皮细胞中的吞饮小泡和微绒毛明显减少;损伤6h后,线粒体出现髓样变和空泡样变性,血管内皮细胞肿胀,管腔变窄;损伤12h后,轴突空泡样变性,髓鞘脱失,毛细血管周围间隙增宽;损伤48h后,轴质密度增加,部分髓鞘板层完全分离,微管、微丝及线粒体发生颗粒性溶解,内皮细胞中的线粒体出现广泛变性;损伤96h时,轴索崩解呈空泡状变性,髓鞘更广泛崩解,毛细血管扩张破裂,红细胞外溢。结论视神经损伤早期轴突肿胀、空泡样变性,线粒体水肿变性,微管、微丝数量减少;视神经内毛细血管扩张,通透性增加。  相似文献   
50.
Psoriasis is a chronic inflammatory skin disease with unclear pathogenesis. Interleukin-33 (IL-33) is highly expressed in patients with psoriasis, but its role in psoriasis is unknown. The aim of this study was to investigate the possible role of IL-33 in the pathogenesis and treatment of psoriasis. IL-33 expression was determined using enzyme-linked immunosorbent assay, real-time fluorescent quantitative polymerase chain reaction and immunohistochemical staining. CD4+ T cells were sorted using magnetic beads and treated with or without IL-33. Imiquimod (IMQ) was used to induce psoriatic inflammation in mice. The frequency of immune cells was determined using flow cytometry. The cytokine level in mouse skin was measured using cytometric bead array. Our results showed that IL-33 was highly expressed in the lesional skin and serum of patients with moderate-to-severe plaque psoriasis. IL-33 inhibited the expression of IL-17 in CD4+ T cells of psoriasis patients. Subcutaneous injection of IL-33 alleviated the IMQ-induced psoriatic inflammation in mice, reduced tumor necrosis factor-α and IL-23 expression, and decreased the proportion of T helper type 17 (Th17) cells in the skin-draining lymph nodes in the mice. Our results suggest that IL-33 plays a protective role in the pathogenesis of psoriasis by suppressing Th17 cell differentiation and function. The potential therapeutic effect of IL-33 in treating psoriasis warrants further investigation.  相似文献   
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