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101.
Germplasm cryopreservation and expansion of gonocytes/prospermatogonia or spermatogonial stem cells (SSCs) are important; however, it's difficult in cattle. Since inhibitors of Mek1/2 and Gsk3β (2i) can enhance pluripotency maintenance, effects of 2i-based medium on the cultivation of bovine prospermatogonia from the cryopreserved tissues were examined. The testicular tissues of newborn bulls were well cryopreserved. High mRNA levels of prospermatogonium/SSC markers (PLZF, GFRα-1) and pluripotency markers (Oct4/Pouf5, Sox2, Nanog) were detected and the PLZF+/GFRα-1+ prospermatogonia were consistently identified immunohistochemically in the seminiferous cords. Using differential plating and Percoll-based centrifugation, 41.59% prospermatogonia were enriched and they proliferated robustly in 2i medium. The 2i medium boosted mRNA abundances of Pouf5, Sox2, Nanog, GFRα-1, PLZF, anti-apoptosis gene Bcl2, LIF receptor gene LIFR and enhanced PLZF protein expression, but suppressed mRNA expressions of spermatogonial differentiation marker c-kit and pro-apoptotic gene Bax, in the cultured prospermatogonia. It also alleviated H2O2-induced apoptosis of the enriched cells and decreased histone H3 lysine (K9) trimethylation (H3K9me3) and its methylase Suv39h1/2 mRNA level in the cultured seminiferous cords. Overall, 2i medium improves the cultivation of bovine prospermatogonia isolated from the cryopreserved testes, by inhibiting Suv39h1/2-mediated H3K9me3 through Mek1/2 and Gsk3β signalling, evidencing successful cryopreservation and expansion of bovine germplasm.  相似文献   
102.
Zhang  Jing  Zhang  Yunqing  Qin  Jinglin  Lu  Sha  Cai  Wenying  Li  Jiahao  Huang  Huaiqiu  Yang  Sulian  Xi  Liyan 《Lasers in medical science》2021,36(1):147-152
Lasers in Medical Science - Onychomycosis is a fungal infection of the nail. The aim of this randomized controlled clinical trial was to compare the efficacy of 2940-nm Er:YAG laser treatment...  相似文献   
103.
To evaluate the safety and efficacy of Chinese medicine, Qiaoshao formula combined with dapoxetine was used for the treatment of premature ejaculation in a real-life setting. Nine hundred and five males diagnosed with premature ejaculation were reviewed in this retrospective cohort study. We divided the patients into two groups: dapoxetine alone and Qiaoshao formula combined with dapoxetine according to actual interventions provided to patients in clinics. The perceived intravaginal ejaculation latency time and the premature ejaculation profile measures markedly improved in both groups. However, in men with severe premature ejaculation (baseline perceived intravaginal ejaculation latency time <1 min) and those with baseline age ≤30 years, the perceived intravaginal ejaculation latency time was slightly but significantly longer with combined therapy than with dapoxetine alone (p < .05). Therefore, combined therapy involving the Qiaoshao formula and dapoxetine proved to safe as well as effective for treating premature ejaculation while prolonging the perceived intravaginal ejaculation latency time, which significantly improved the overall satisfaction of the patient and likely that of the couple.  相似文献   
104.
This study aimed at the efficacy of sequential treatment of bone marrow-derived mesenchymal stem cell secretion for busulfan-treated azoospermia in mice. The conditioned media (CM) was obtained from bone marrow mesenchymal stem cells (MSCs) or 293 cells. Chemically induced azoospermia mice received 200 μl MSC-CM or 293-CM twice a week intravenously for three consecutive weeks. The histological assessment of spermatogenic recovery quantifying the expression of meiosis-associated genes, and Sertoli cell barrier functional factors were assessed. The characteristics of TM4 cells (Sertoli cell line) after pre-incubation of MSC-CM in vitro were also obtained. The MSC-CM group had the most spermatogenic colonies among the three groups (p < .05), but no spermatids were seen. Expressions of the meiosis-associated genes Dazl, Vasa, Miwi, Stra8, CyclinA1, Pgk2 and Scp3 in MSC-CM testis were remarkably higher compared with 293-CM and busulfan groups respectively (p < .05). The levels of Sertoli cell barrier functional factors, for example ICAM-1 and N-cadherin, were significantly increased during MSC-CM treatment (p < .05). Moreover, pre-incubation of MSC-CM particularly accelerated the CD54 (ICAM-1) and CD44 expressions of TM4 cells and promoted cell inherent adhesion. MSC-CM treatment can significantly improve the short-term restoration of spermatogonial structures of chemically induced azoospermia related to facilitating Sertoli cell adhesion integrity.  相似文献   
105.
Hepatic ischemia–reperfusion injury (HIRI) is of common occurrence during liver surgery and transplantation. Pinocembrin (PIN) is a kind of flavonoid monomer extracted from the local traditional Chinese medicine Penthorum chinense Pursh (P. chinense). However, the effect of PIN on HIRI has not determined. We investigated the protective effect and potential mechanism of PIN against HIRI. Model mice were subjected to partial liver ischemia for 60 min, experimental mice were pretreated with PIN orally for 7 days, and H2O2-induced oxidative damage model in AML12 hepatic cells was established in vitro. Histopathologic analysis and serum biochemical levels revealed that PIN had hepatoprotective activities against HIRI. The variation of GSH, SOD, MDA, and ROS levels indicated that PIN treatments attenuated oxidative stress in tissue. PIN pretreatment obviously ameliorated apoptosis, and restrained the expression of HMGB1 and TLR4 in vivo. In vitro, compared with H2O2 group, the contents of ROS, mitochondrial membrane potential, apoptotic cells, and Bcl-2 protein were decreased, while the Bax protein expression was increased. Moreover, HMGB-1 small interfering RNA test and western blotting showed that PIN pretreatment reduced HMGB1 and TLR4 protein levels. In conclusion, PIN pretreatment effectively protected hepatocytes from HIRI and inhibited the HMGB1/TLR4 signaling pathway.  相似文献   
106.
目的评价腹壁疝内镜下全腹膜外Sublay(TES)手术的效果并总结经验。方法回顾性总结国内10所医院自2016年3月至2019年7月115例腹壁疝内镜下TES手术的患者资料。分析患者情况、疝的特点、手术经过和结果。结果115例计划实施TES的患者中,因严重腹膜破损中转为IPOM修补患者1例,其余均成功手术。可以缝合缺损患者108例(94.74%),需要永久补片固定患者15例(13.16%)。放置引流患者76例(66.67%),中位手术时间为144 min,术中无严重并发症发生。随访时间3~45个月,总并发症发生率为20例(17.54%),其中出现血清肿患者5例(4.38%)。绝大多数患者术后仅出现轻微疼痛,未出现慢性疼痛。结论在腹壁疝的治疗中,对熟悉腹壁解剖的外科医师而言,TES是一种有效、安全的修复手段。在熟悉手术的基础上适应症可逐步拓展。  相似文献   
107.
ObjectiveTo explore the effect of a PEEK material‐based external fixator in the treatment of distal radius fractures with non‐transarticular external fixation.MethodsThere were 48 patients in this prospective comparative study. They were divided into two groups according to the materials used: the PEEK group and the titanium group. Wrist dorsiflexion, palmar flexion, pronation, supination, radial deviation, ulnar deviation, grip strength of the palm on the affected side, kneading force, Visual Analogue Scale/Score (VAS), Disabilities of the Arm, Shoulder, and Hand (DASH) score, operation time, frequency of fluoroscopy procedures, and X‐ray results were compared between the two groups. Functional recovery was evaluated at the last follow‐up according to the wrist joint evaluation criteria.ResultsThe baseline data were comparable between the two groups, and no significant differences were found in age, sex, fracture types (P > 0.05). There was no significant difference between the two groups in the results of DASH, grip strength, and recovery of pinch force and wrist function (dorsiflexion, clavicle, ulnar deviation, deviation, pronation, and supination) (P > 0.05). Normal limb function was achieved in the two groups of patients at an average of 6 weeks after surgery, and there was no significant difference in X‐ray examination radial height (10.60 ± 1.59 vs 11.00 ± 1.53, P = 0.687), radial inclination (1.11 ± 0.24 vs 1.12 ± 0.24, P = 0.798), volar tilt (10.33 ± 2.13 vs 10.00 ± 2.08, P = 0.660), ulnar variance (20.87 ± 3.00 vs 20.38 ± 3.04, P = 0.748), and step‐off persistence (1.73 ± 0.69 vs 1.68 ± 0.72, P = 0.425) between the two groups (P > 0.05). However, the operation time (54.80 ± 12.20 vs 85.23 ± 15.14, P = 0.033) and number of fluoroscopy procedures (36.93 ± 6.89 vs 64.77 ± 9.74, P = 0.000) in the PEEK group were significantly reduced compared with those in the titanium group.ConclusionCompared with the traditional titanium external fixator, the PEEK composite external fixator has advantages, such as a shorter operation time and fewer fluoroscopy procedures when used to treat different types of distal radius fracture.  相似文献   
108.
109.
用地高辛标记反意前阿黑皮素(pro-opiomelanocortin,POMC)cRNA探针原位杂交组化在光镜和电镜水平观察了POMC mRNA在大鼠垂体的分布,并比较了碱性磷酸酶(AKP)显色系统和辣根过氧化酶(HRP)显色系统在光镜水平上的敏感性.结果:POMC mRNA广泛地分布于垂体的中间叶和前叶.中间叶全部细胞均为POMC mRNA阳性.前叶中除前叶的腹侧缘和前叶与中间叶交界处阳性细胞较少外,都有较多的POMC mRNA阳性细胞分布.AKP显色系统比HRP显色系统敏感.在电镜水平,POMC mRNA主要分布于粗面内质网,少数分泌颗粒可能呈阳性反应,胞核未见阳性反应沉淀.文内还就阳性分泌颗粒在调节细胞合成功能方面可能起的作用进行了讨论.  相似文献   
110.
桥粒斑蛋白II(DPII)是一种新的上皮和上皮性肿瘤标记物。我们应用针对石蜡切片的抗DPII单抗和抗细胞角蛋白(CK)单抗对2l7例肿瘤作了免疫组织化学ABC法染色的研究,结果:在163例上皮性肿瘤和双向分化的肿瘤中,147例表达DPII,占90.7%,92例表达CK,占56.4%。CK阳性染色全部位于细胞浆内,DPII阳性染色则同时分布在细胞交界面上和细胞浆中。其他54例不含桥粒的肿瘤均无DPII和CK表达。结果表明,DPII单抗是有用的含桥粒肿瘤的免疫组化探针。因DPII不存在于一切含桥粒肿瘤,故在鉴别上皮性肿瘤时,DPII单抗尚需与其他上皮标记物的抗体合并使用。  相似文献   
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