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941.
亚胺培南诱导常见革兰阴性杆菌产生AmpC酶的研究 总被引:1,自引:0,他引:1
目的:了解亚胺培南对鲍氏不动杆菌,阴沟肠杆菌、铜绿假单胞菌、以及产ESBLs的大肠埃希菌和肺炎克雷伯菌等常见革兰阴性杆菌透导性AmpC酶的发生率。方法:采用底物协同—拮抗法(MSSAT)检测大肠埃希菌,肺炎克雷伯菌,铜绿假单胞菌,鲍氏不动杆菌和阴沟肠杆菌产AmpC酶的情况及构成。结果:产ES- gLs的大肠埃希菌和肺炎克雷伯菌、铜绿假单胞菌、阴沟肠杆菌、鲍氏不动杆菌AmpCs酶的检出率分别为20.7%,23.1%,76%,75%,87.9%;高诱导型AmpC酶的检出率分别为0,15.4%,44%,35%,9.1%;部分去阻遏型AmpC酶的检出率分别为3.5%,7.7%,16%,30%,15.2%;完全去阻遏型AmpC酶的检出率分别为17.2%,0%,16%,10%,63.6%。结论:亚胺培南对铜绿假单胞菌和阴沟肠杆菌产AmpC酶具有高度诱导性,而对产ESBLs大肠埃希菌和肺炎克雷伯菌及鲍氏不动杆菌诱导性低,应引起临床和实验室的重视;AmpC酶的诱导表型与菌株的耐药程度相关。 相似文献
942.
不同临床和病理分型对肝门部胆管癌切除术预后的影响 总被引:2,自引:0,他引:2
目的 研究临床和病理分型与肝门部胆管癌切除术疗效的关系。方法总结1993年至2004年在解放军总医院肝胆外科手术切除的肝门部胆管癌198例病例资料。结果临床分型Ⅰ型34例,Ⅱ型60例,Ⅲa型27例,Ⅲb型33例,Ⅳ型19例,Ⅴa型6例。Ⅴb型19例。病理高分化腺癌35例,中分化腺癌52例,低分化腺癌54例,三者的中位生存期分别为29.5、11、5.5个月;病理切缘阴性者与切缘阳性者生存率有显著性差异(P 〈0.05)。手术并发症出现率41.4%,围手术期死亡1例。结论肝门部胆管癌根据临床分型进行相应的手术治疗;病理切缘阴性是影响预后的主要因素之一;围手术期正确处理,是减少手术并发症,提高患者生活质量和延长生存期的关键。 相似文献
943.
Study on biocompatibility of complexes of collagen-chitosan-sodium hyaluronate and cornea 总被引:4,自引:0,他引:4
In this study we investigated the biocompatibility of collagen-chitosan-sodium hyaluronate (Col-Chi-NaHA) complexes and cornea tissue, and the feasibility of Col-Chi-NaHA complexes as substrates for cultivating rabbit corneal cells. Different components of Col-Chi-NaHA complexes were prepared and tested. A circular complex film with a diameter of 6 mm was inserted into rabbit stomal pocket and traced for a period of 5 months. Clinical examination was made. Rabbit limbal corneal epithelial cells, corneal endothelial cells, and keratocytes were cultured primarily on complexes. Phase contrast microscope examination was made daily. Histological, immunohistochemical, and scanning electron microscopic examinations were carried out. The complexes of 20% collagen, 10% chitosan, and 0.5% sodium hyaluronate showed rather weak corneal edema and other responses. The degradation of materials was obvious after 5 months. Corneas were transparent and translucent. Cells seeded on Col-Chi-NaHA were allowed to proliferate and partly form confluent monolayer after 9 days in culture. Cultured cells were well attached to the complexes of 20% collagen, 10% chitosan, and 0.5% sodium hyaluronate, or 10% chitosan and 0.5% sodium hyaluronate. The results showed that Col-Chi-NaHA complexes had good biocompatibility with cornea. The complexes can degrade and be absorbed in cornea. Col-Chi-NaHA complex may be a suitable substrate for cultivating corneal cells and a feasible material as a scaffold of tissue-engineered cornea. 相似文献
944.
Baldwin ZK Chandiwal A Balasubramanian V Pearce BJ Curi MA Skelly CL Huang WW Vosicky JE Roizman B Weichselbaum RR Schwartz LB 《Journal of vascular surgery》2005,41(1):115-121
OBJECTIVE: Vascular remodeling in response to injury or low shear stress (or both) is characterized by neointimal hyperplasia and luminal contraction. When profound, the response leads to restenosis after percutaneous endovascular intervention as well as to de novo stenosis in vein grafts. It has recently been reported that exposure of vein patches to neurovirulence-attenuated Herpes simplex virus-1 (HSV-1) decreases neointimal hyperplasia and increases luminal area. This experiment tested the hypothesis that R7020, a more highly attenuated mutant of HSV-1, would modulate the vascular remodeling response of experimental vein grafts chronically exposed to low shear stress. METHODS: The external jugular veins of 31 New Zealand white rabbits were clamped and intraluminally exposed to vehicle (phospate-buffered saline solution, n = 11), R7020 2.5 x 10(8) plaque forming units [PFU]/mL (n = 8), or R7020 2.5 x 10(9) PFU/mL (n = 12) for 10 or 30 minutes at an average pressure of 80 mm Hg. After exposure, an end-to-side distal external jugular-to-common carotid artery anastomosis was created, resulting in a widely patent arteriovenous fistula. The external jugular was suture-ligated just proximal to the thoracic inlet, distal to a small 10- to 50-microm venous tributary, creating a reversed vein "graft" segment immediately and abruptly exposed to arterial pressure (48 +/- 3 mm Hg) and low shear stress (0.12 +/- .02 dyne/cm(2)). In the 29 animals (N = 31) that survived to harvest, 26 grafts were found to be patent and were analyzed further. Nine grafts were harvested within the first week after operation, snap frozen in liquid nitrogen, and assayed for the presence of the Herpes viral immediate-response protein ICP0 by Western blot analysis. The 17 remaining grafts were perfusion-fixed, excised, stained, and analyzed morphometrically by digital planimetry. RESULTS: In patent grafts, the hemodynamic environment of low shear stress was maintained (shear stress at harvest, 0.26 +/- .06 dyne/cm(2)). Western blot analysis revealed the presence of ICP0 in R7020-exposed vein grafts after 2, 3, 7, and 14 days; ICP0 was not detected in unexposed vein grafts or adjacent carotid arteries. After 4 weeks, vein grafts exposed to R7020 exhibited a statistically significantly increased ratio of luminal radius to wall thickness, indicating altered remodeling (vehicle, 6.7 +/- 1.3; R7020 2.5 x 10(8), 9.1 +/- 1.3; R7020 2.5 x 10(9) ratio, 11.3 +/- 1.4; P < .05 for high dose compared with vehicle). CONCLUSION: A brief exposure of the neurovirulence-attenuated HSV-1 strain R7020 results in an increased ratio of luminal radius to wall thickness in experimental vein grafts chronically exposed to low shear stress. 相似文献
945.
Xiao-Ping?ChenEmail author Zhi-Yong?Huang 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2005,390(3):259-265
Background and aims Surgery remains the most effective treatment for hepatocellular carcinoma (HCC). While resection and liver transplantation achieve the best outcomes in patients with small HCC, controversy surrounds treatment of large HCC, HCC with portal vein tumor thrombus, and HCC with hypersplenism.Patient/methods From January 1988 to December 2002, 2,102 patients with large HCC underwent hepatectomy in our hospital. The traditional resection method was used on 959 patients, after which the improved new method was used on 1,143 patients. Meanwhile, from January 1990 until December 2003, hepatic resection ± thrombectomie has been performed in 438 patients with HCC and portal vein tumor thrombus. Among them, 286 patients showed portal vein tumor thrombus located in the primary and secondary branch of the main portal vein (group A), and 152 patients showed portal vein tumor thrombus (PVTT) involved in the main portal vein (group B). Additionally, out of 204 HCC patients with cirrhotic hypersplenism, 94 patients had hepatectomy and splenectomy, and 100 patients had only hepatectomy without hospital death.Results The 3- and 5-year survival after resection of large HCCs (over 5 cm) with improved new method in China was between 50.7 and 58.8% and 27.9 and 38.7%, respectively. Tumor recurrence in the liver within 1 year after hepatic resection + thrombectomie was detected in 45% of group A and in 78.8% in group B. The cumulative 5-year overall survival rates were 18.1% for group A and 0% for group B. The 1-, 3-, and 5-year overall survival in HCC plus portal vein tumor thrombus (PVTT) was 58.7, 22.7, and 18.1%. The hepatectomy/splenectomy group had a 5-year tumor-free survival rate of 37.2% and the hepatectomy group alone had 27.2%.Conclusion The new resection methods, hepatic resection + thrombectomy and hepatectomy + splenectomy, are very effective treatments for large HCC, HCC with portal vein tumor thrombus, and HCC with hypersplenism, respectively. Local treatment modalities, e.g. percutaneous ethanol injection, cryosurgery, and radiofrequency ablation as well as microwave coagulation are used in patients with poor liver function in small and large HCCs. 相似文献
946.
Recurrent laryngeal nerve palsy after thyroidectomy with routine identification of the recurrent laryngeal nerve 总被引:21,自引:0,他引:21
BACKGROUND: The aim of this study was to assess the risk of recurrent laryngeal nerve palsy (RLNP) after thyroidectomy with routine identification of the recurrent laryngeal nerve (RLN) during the operation. METHODS: The present study was confined to 521 patients, 348 total lobectomies and 178 total thyroidectomies, treated by the same surgeon. Temporary and permanent RLNP rates were analyzed for patient groups with stratification of primary operation for benign thyroid disease, thyroid cancer, Graves' disease, and reoperation. Measurement of the RLNP rate was based on the number of nerves at risk. Twenty-six RLNs in 20 thyroid cancer patients with intentional sacrifice were excluded from analysis. RESULTS: Forty RLNs (40 patients) developed postoperative RLNP. Complete recovery of RLN function was documented for 35 of the 37 patients (94.6%) whose RLN integrity had been ensured intraoperatively. Recovery from temporary RLNP ranged from 3 days to 4 months (mean, 30.7 days). Overall incidence of temporary and permanent RLNP was 5.1% and 0.9%, respectively. The rates of temporary/permanent RLNP were 4.0/0.2%, 2.0/0.7%, 12.0/1.1%, and 10.8/8.1% for groups classified according to benign thyroid disease, thyroid cancer, Graves' disease, and reoperation, respectively. CONCLUSIONS: Operations for thyroid cancer, Graves' disease, and recurrent goiter demonstrated significantly higher RLNP rates. Invasion of RLN was identified in 19.4% of patients with thyroid cancer. Postoperatively, the RLN recovered in most of the patients without documented nerve damage during the operation. Total lobectomy with routine RLN identification is recommended as a basic procedure in thyroid operations. 相似文献
947.
Topical high-molecular-weight hyaluronan and a roofing barrier sheet equally inhibit postlaminectomy fibrosis. 总被引:9,自引:0,他引:9
Wayne H Akeson Jennifer B Massie Bill Huang Alexander Giurea Robert Sah Steven R Garfin Choll W Kim 《The spine journal》2005,5(2):180-190
BACKGROUND CONTEXT: The relevance of epidural fibrosis to failed back surgical outcomes remains controversial. Previous studies on the correlation between epidural fibrosis and clinical outcome after laminectomy are inconclusive, and clinical approaches applied to reduce postlaminectomy spinal canal scarring have produced mixed outcomes. PURPOSE: Improved preclinical models are required to address the fundamental question of the relationship between postlaminectomy fibrosis and chronic pain. This study is directed at establishing small animal postlaminectomy models characterized by significantly reduced scar within the spinal canal postoperatively. Such preclinical models are offered as a platform for future studies to explore the potential relationship between postlaminectomy epidural fibrosis and persistent neuropathy with its potential for altered spinal mechanisms for pain processing, so-called spinal facilitation. Such experiments could be constructed in these models for comparison of pain behavior and its underlying neurochemistry both in the presence and absence of extensive postlaminectomy epidural scar. STUDY DESIGN/SETTING: A modified rat laminectomy model was employed to assess epidural fibrosis using a quantitative biochemical collagen assessment approach along with correlative histology. This group served as the control for comparison with groups in which antifibrotic measures were employed. We compared antifibrotic efficacy of a bioabsorbable roofing barrier sheet placed over the laminectomy defect with topical high-molecular-weight hyaluronan (HMW HA) gel, each applied postoperatively to prevent proliferative epidural scarring. Routine biomechanical tensile strength testing was employed to assess wound-healing strength. METHODS: A bilateral laminectomy (L5 and L6) with associated unilateral disc injury (L5-L6) was performed in 98 male Harlan Sprague-Dawley rats. The laminectomy models described incorporated a unilateral disc injury at L5-L6 because herniated disc material has been shown to contribute proinflammatory cytokines in the postoperative wound. Five groups were employed for the study: 1) normal controls without surgery; 2) a laminectomy-disc injury group without treatment; 3) a laminectomy-disc injury group treated with topical HMW HA gel; 4) a laminectomy-disc injury group treated with 0.2-mm thick bioabsorbable roofing barrier sheet in which a protected space was maintained between overlying paraspinous muscles and the dura and 5) a 0.02-mm thin barrier sheet treatment group in which the sheet was placed directly on the dura. The animals were sacrificed at 3- and 8-week postoperative intervals for analysis. The dissected specimens were studied biochemically for hydroxyproline content to estimate total collagen within the canal and on the dura between L4 and L7. Additional specimens were prepared histologically and stained with Masson-Goldner Trichrome stain to confirm presence of proliferative collagen and to describe the presence or absence of wound-healing scar adherence to the dura. The surgical incisions were studied biomechanically by uniaxial tensile testing to determine ultimate force, strain and prefailure stiffness. Statistics were performed using analysis of variance. RESULTS: Gross appearance and histology studies showed that the untreated laminectomy group demonstrated postoperative scar formation that is adherent between the wound and the dorsum of the dura mater in both 3- and 8-week groups. Proliferative scar was substantially increased grossly between the 3- and 8-week intervals. By gross observation there was adherence of the L5 spinal nerve to the underlying disc and adjacent pedicle on the disc injury side. Gross observation of treatment groups, in contrast, disclosed that both the 0.2-mm thick roofing barrier sheet and topical HMW HA gel each prevented scar attachment to the dural sleeve at both the 3- and 8-week postoperative intervals. Furthermore, both the HMW HA gel and 0.2-mm thick roofing barrier sheet treatment groups had significant reduction of total collagen content in the laminectomy specimens measured biochemically at the two time periods compared with the untreated controls. Histologically, the HMW HA gel and the 0.2-mm thick barrier sheet findings were consistent with the gross observations concerning lack of adherence between scar of the overlying wound and the dura. Notably, both the 0.2- and the 0.02-mm barrier sheets became enveloped by a fibrotic envelope consistent with a foreign body reaction. In the group in which the 0.02-mm thin sheet was placed within the canal on top of the dura, there was an increase of fibrosis around the sheet within the canal leading to a space-occupying mass within the canal. Although the 0.2-mm thick roofing barrier placed external to the canal became enveloped by scar, it appeared to attract proliferative scar away from the epidural space, leaving the dura relatively free of scarring or adherence to overlying tissues. The mechanical properties of the incisional wound increased significantly between 3 and 8 weeks. The ultimate strength, stress, strain and stiffness of the several groups were similar at each time point. CONCLUSION: These results provide two preclinical rat laminectomy models of potential usefulness for the future study of the relevance of epidural fibrosis to behaviorally defined pain states, and for the study of the potential of an altered neurochemical signature in postlaminectomy pain conditions. Such preclinical models have become standard in studies of pain behavior and its neurochemistry in preclinical sciatic nerve and spinal nerve injury models, and should be of utility in the studies of postlaminectomy fibrosis. There was progressive scar proliferation and maturation in the untreated postlaminectomy group in the postoperative interval between 3 and 8 weeks. HMW HA gel applied topically and a 0.2-mm thick bioabsorbable Macropore sheet used as a roofing barrier each significantly reduced postlaminectomy proliferative scar without affecting the integrity of incisional wound healing. However, if the 0.02-mm thin barrier sheet used in this study is placed within the canal in contact with the dura and adjacent to the pedicles, the process of reabsorption results in a fibrotic mass within the canal. The preferred barrier sheet placement for this model is clearly in a roofing position bridging over the open epidural space. It must be placed in a manner to block off the paraspinous muscle healing response and still leave a gap between the sheet and the dura. 相似文献
948.
Chen SC Hsieh CH Hsu GL Wang CJ Wen HS Ling PY Huang HM Tseng GF 《Journal of andrology》2005,26(1):53-60
Our aim was to study retrospectively the destiny of the deep dorsal vein of the penis in the event of its stripping surgery or its simple ligation in patients diagnosed with venoocclusive dysfunction 17 years ago. From June 1986 to May 1987, a total of 31 men were seen for erectile dysfunction due to venous leakage resulting from priapism, aging, or congenital or idiopathic factors. Of these, 23 men underwent venous stripping of the deep dorsal vein and are referred to as the stripping group. The remaining 8 patients received a simple ligation of the deep dorsal vein and are classified as the ligation group. A total of 21 patients (16 of the 23 and 5 out of the 8) were available for follow-up by using the abridged 5-item version of the International Index of Erectile Function (IIEF-5) scoring system and cavernosograms. In the ligation group, the imaging demonstrates some compensatory veins that are commensurate with impotence postoperatively. In the stripping group, however, the follow-up cavernosograms disclosed no venous recurrence, but residual ones that were not crucial to the rigidity. The IIEF-5 scoring in the ligation group changed from a preoperative mean IIEF-5 score of 10.0 +/- 4.5 to 9.8 +/- 3.6 postoperatively. In the stripping group, however, the mean preoperative IIEF-5 score of 9.8 +/- 4.1 increased to a mean postoperative IIEF-5 score of 18.9 +/- 2.1. Although there was no significant difference between the 2 groups' preoperative IIEF-5 score, there was a statistically significant difference between treatments (P <.001). The penile venous vasculature bears no evidence of regeneration even as long as 17 years after their removal. This finding is in contrast to what is commonly believed, that erectile dysfunction will recur about 2 years after ligation of the deep dorsal vein. We therefore believe that the clinical recurrence may not be due to venous regeneration, and penile venous surgery, if properly performed, may be durable, although larger studies will be required. 相似文献
949.
目的:制定人工关节置换术后下肢肿胀的分度标准,对比观察术后早期持续被动活动(continuous passive motion,CPM)对肿胀的预防作用。方法:自2001年6月~2004年10月对接受人工全髋、膝关节置换术的患者128例(144个关节)根据术后处理办法的不同,前瞻性地将其随机分成A组(手术8h后利用CPM机进行患肢持续被动活动功能锻炼)和B组(手术一周后开始进行CPM机功能锻炼)。手术后第4d观察两组患者下肢的肿胀情况,根据制定标准评分,分为轻、中、重度肿胀,统计每组中、重度肿胀的病例数,采用SPSS10.0统计分析软件进行统计学分析。结果:A组69个关节(62例患者)中有10侧下肢出现不同程度肿胀,B组75个关节(66例患者)中有25侧下肢呈不同程度肿胀,经统计学分析差异有显著性意义(P〈0.05)。结论:人工关节置换术后早期进行患肢持续被动活动对手术后肢体肿胀有明显的预防作用。可以作为关节置换术后早期预防深静脉血栓形成的常规疗法之一。 相似文献
950.
目的 探讨肱骨髁间骨折的手术方式并评价疗效。方法 1998年1月~2004年12月共手术治疗肱骨髁间骨折28例,进行随访分析。结果 28例中26例获随访,时间6个月~4年7个月,其中22例获2年以上随访。疗效评价参照casse‰。评分系统,优良率为65%。结论 骨折类型及手术方式直接影响预后。关节良好的复位和牢固的固定,以及术后早期积极的功能锻炼是得到良好疗效的保证。 相似文献