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21.
目的探讨胚胎脊髓神经干细胞移植对大鼠脊髓损伤后CD-95和p75表达及神经细胞凋亡的影响。方法160只sD大鼠随机分为空白组,假手术组,脊髓损伤组,细胞移植组,分别在细胞移植后1、3d、1、2、4周应用苏木素-伊红(HE)染色)、免疫组织化学、Tunel(凋亡测定)标记、电镜方法观察CD-95、p75和神经细胞凋亡的变化。结果移植后1、3d、1、2、4周,脊髓损伤组和细胞移植组比较,CD95(P〈0.05);p75,P〈0.01。Tunel方法测定细胞凋亡结果,差异有统计学意义(P〈0.05)。电镜观察可见,空白对照组和假手术组未见凋亡现象,细胞移植后1周,损伤对照组电镜下可见大量神经细胞凋亡小体。细胞移植组未见凋亡小体。结论脊髓源性神经干细胞移植后减少了CD-95和p75的表达,也减少了凋亡,说明移植促进了脊髓神经功能的恢复,也抑制了继发性脊髓损伤。  相似文献   
22.
Atrial myxomas are the most common benign tumors of the heart and are difficult to diagnose due to a wide variety of presenting symptoms. We present a patient with a five-year history of visual loss, vertigo, ataxia, tinnitus, and bone lesions that resolved after diagnosis and resection of an atrial myxoma. This case not only highlights an unusual presentation of atrial myxomas but also raises the question of whether atrial myxomas can produce paraneoplastic syndromes, including bone abnormalities.  相似文献   
23.
BACKGROUND: Single-stapled double-pursestring technique for colorectal anastomosis to the mid-rectum or upper rectum is the most commonly used technique in the single institution reported here. The investigators evaluate single-stapled double-pursestring anastomosis after anterior resection of the rectum performed at a single institution. METHODS: Medical records of patients who underwent single-stapled double-pursestring anastomosis between January 2000 and May 2005 were analyzed to identify postoperative anastomotic complications. Patients with previous radiation, diverting stoma, coloanal, and hand-sewn and double-stapled anastomoses were excluded. The primary goal was to identify postoperative anastomotic complications. RESULTS: Of 160 patients, 153 (96%) no septic complications. One patient (.6%) developed anastomotic leak requiring diversion. Of the 4 patients with pelvic abscesses (2.5%), 2 were treated with antibiotics and 2 with computed axial tomography-guided drainage. CONCLUSIONS: Single-stapled double-pursestring anastomosis is reliable, with very low rates of leak, subsequent diversion, and pelvic abscess (.6%, .6%, and 2.5% respectively).  相似文献   
24.
Different immunosuppressant regimens vary in their effects on antibody responses to vaccination. The combination of prednisolone and azathioprine has only a minor effect, whereas the addition of ciclosporin attenuates protective antibody responses to influenza vaccination. The effect of sirolimus, a new immunosuppressant, on vaccine responses has been little studied. Thirty-two hepatic or renal transplant patients randomized to calcineurin inhibitor-based or sirolimus-based immunosuppression were vaccinated against influenza and pneumococcus. Following tri-valent influenza vaccination, a similar rise in antibody titer occurred in sirolimus and calcineurin inhibitor (CNI) treated patients, though sirolimus treated patients developed a 'protective' titer to more influenza antigens. The pneumococcal polysaccharide vaccine was equally effective in both groups. Hence, vaccination guidelines in place for CNI treated patients are likely to be appropriate for transplant recipients maintained on sirolimus.  相似文献   
25.
 目的 探讨锌指蛋白ZFP580在体外蛙皮素诱导的胰腺腺泡细胞炎性反应过程中通过内质网应激通路发挥作用的机制,为急性胰腺炎(acute pancreatitis, AP)发病机制提供新的认识。方法 用蛙皮素体外刺激AR42J细胞,模拟AP过程中胰腺腺泡细胞的炎性反应状态,用MTT法测定细胞活力以确定蛙皮素的最佳诱导时间;分别用RT-PCR和Western Blot检测细胞中内质网应激相关分子和ZFP580的mRNA和蛋白表达;应用IRE1抑制剂MKC-3946干预AR42J细胞,观察ZFP580表达变化;最后用慢病毒转染方法沉默ZFP580后,用Hochest33342染色和RT-PCT、Western Blot评价其对细胞凋亡-坏死的影响。结果 以蛙皮素刺激后诱导AR42J细胞发生内质网应激,ZFP580表达在刺激8 h后开始升高,呈时间依赖性上升;应用MKC-3946后,ZFP580的表达显著降低;沉默ZFP580后,XBP-1s表达下降,同时沉默ZFP580组的Chop表达量要显著高于对照组,而Caspase-3的表达显著低于普通AP组;Hochest染色观察发现沉默ZFP580组的坏死细胞比例要显著高于普通AP组。结论 ZFP580在胰腺腺泡细胞内质网应激信号通路中的位置可能位于IRE1与XBP-1s之间,其可能通过改善凋亡-坏死比例,对减轻AP炎性反应有一定作用。  相似文献   
26.

Background  

Fistula-in-ano is a common medical problem affecting thousands of patients annually. In the past, the options for treatment of fistula-in-ano were limited to fistulotomy and/or seton placement. Current treatment options also include muscle-sparing techniques such as a dermal island flap, endorectal advancement flap, fibrin sealent injection, anal fistula plug, and most recently ligation of the intersphincteric fistula tract (procedure). This study seeks to evaluate types and time trends for treatment of fistula-in-ano.  相似文献   
27.
Background: Preoperative chemotherapy for stage II breast cancer may reduce locoregional tumors and provides initial treatment for systemic micrometastases. We conducted a prospective, randomized trial to evaluate the ability of intensive preoperative chemotherapy to enhance the outcome of this approach.Methods: Patients with clinical stage II breast cancer (T2N0, T1N1, and T2N1) were prospectively randomized to receive either preoperative or postoperative chemotherapy with five 21-day cycles of fluorouracil, leucovorin calcium, doxorubicin, and cyclophosphamide (FLAC)/granulocyte-colony-stimulating factor. Local therapy consisted of modified radical mastectomy or segmentectomy/axillary dissection/breast radiotherapy, according to patient preference.Results: Fifty-three women were randomized (26 preoperative chemotherapy and 27 postoperative chemotherapy). The objective clinical response rate of the primary tumor to preoperative chemotherapy was 80%, and the pathologic complete response rate was 20%. Preoperative chemotherapy reduced the overall incidence and number of axillary lymph node metastases. There was no difference in the use of breast-conserving local therapy between the two treatment arms. There were 20 local/regional or distant recurrences (9 preoperative and 11 postoperative). There was no difference in the overall or disease-free survival between the preoperative and postoperative chemotherapy arms.Conclusions: Preoperative FLAC/granulocyte-colony-stimulating factor chemotherapy was effective against local/regional tumors in stage II breast cancer but was otherwise comparable to postoperative chemotherapy.  相似文献   
28.
29.

Introduction

Silver dressings are an integral part of the management of burn patients. Package inserts assert a lack of compatibility and safety with magnetic resonance imaging (MRI) and recommend removal prior to any MRI procedure, although there is no clear evidence to support this recommendation. Dressing removal is associated with increased pain, anxiety, stress, and analgesia use. This study was to determine whether these products produce MRI image distortion or if the agitation of the silver particles generates enough heat which might produce further skin damage.

Methods

Hind limbs from euthanized pigs were used in a 7 T MRI scanner with three standard silver wound dressings. Images were obtained with both dry and wet dressings. Temperature was assessed before and during MRI by probes inserted between the dressing and skin. Images were independently reviewed by a radiologist and MR physicist for distortion.

Results

None of the dressings exhibited significant temperature increases nor produced significant distortion that influenced imaging quality.

Conclusion

Our data suggests silver containing wound dressings do not cause a significant increase in dressing temperature or image distortion and thus their removal is not warranted for clinical MRI examinations.  相似文献   
30.
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