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71.
The treatment of Klebsiella pneumoniae, particularly extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae, is currently a great challenge. Photodynamic antimicrobial chemotherapy is a promising approach for killing antibiotic-resistant bacteria. The aim of this study was to evaluate the capacity of 5-aminolevulinic acid (5-ALA) and its derivative 5-ALA methyl ester (MAL) in the presence of white light to cause photodynamic inactivation (PDI) of K. pneumoniae planktonic and biofilm cells. In the presence of white light, 5-ALA and MAL inactivated planktonic cells in a concentration-dependent manner. Biofilms were also sensitive to 5-ALA and MAL-mediated PDI. The mechanisms by which 5-ALA and MAL caused PDI of ESBL-producing K. pneumonia were also investigated. Exposure of K. pneumonia to light in the presence of either 5-ALA or MAL induced cleavage of genomic DNA and the rapid release of intracellular biopolymers. Intensely denatured cytoplasmic contents and aggregated ribosomes were also detected by transmission electron microscopy. Scanning electron microscopy showed that PDI of biofilms caused aggregated bacteria to detach and that the bacterial cell envelope was damaged. This study provides insights into 5-ALA and MAL-mediated PDI of ESBL-producing K. pneumoniae.  相似文献   
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Carcinoma of the lip is a common cancer of head and neck area. It occurs frequently on the lower lip of middle-aged and elderly males who have a history of chronic sun exposure. Surgical excision and radiotherapy are regarded as equally effective treatment options, but preferred method is surgical excision. Karapandzic technique provides myoneurovascular pedicled advancement flap for reconstruction of the defect after surgical excision. It is a simple and safe technique, functionally and esthetically, sacrifices little tissue, heals rapidly and is effective for repair of defects covering 1/3 to 4/5 of the lower lip. We report a 62 years male who presented with a large, fungating, pus-discharging and tender mass of lower lip. Biopsy confirmed squamous cell carcinoma. Tumor was excised and defect was reconstructed using Karapandzic technique. Patient remained asymptomatic during follow-up visits.  相似文献   
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Background  The potential for massive hemorrhage imposes additional challenge in the management of retroperitoneal tumors. This report details technical considerations for the management of upper retroperitoneal tumors using principles of liver transplantation. Methods  A retrospective chart review of patients who underwent surgery for extensive retroperitoneal tumors using techniques for liver transplantation from December 2002 to November 2007 was done. Results  Twenty-four patients (14 males and 10 females with a mean age 57 years) underwent major retroperitoneal surgery. Renal cell carcinoma was the most common tumor seen in 17 patients. Mean tumor dimension was 12.4 cm. Abdominal exposure was achieved via bilateral subcostal incision with upper midline extension. Right hepatic lobe mobilization and isolation from the inferior vena cava (IVC) was performed in 23 cases. Fourteen patients had IVC involvement by tumor thrombus, which was infrahepatic in six, retrohepatic in five, and intra-atrial in three patients. Tumor thrombus was removed by cavotomy in seven cases, resection and plasty in four cases, IVC graft reconstruction in two cases, and one patient required IVC and atrial graft reconstruction. Liver resection was needed in seven patients to achieve R0 resection. The Pringle maneuver was used in three patients; total liver vascular isolation with venovenous bypass was required in two cases, transdiaphragmatic intrapericardial IVC control in one case, and cardiopulmonary bypass in one patient. There was no intraoperative or postoperative mortality and mean length of stay was 13 days. Conclusion  Liver transplantation surgical principles help achieve exposure and vascular control of major vascular structures that enable safe resection of these extensive retroperitoneal tumors.  相似文献   
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Adult intussusception is rare, making-up only about 1% of the causes of bowel obstruction intussusception, secondary to an inverted Meckel's diverticulum, is also a rare occurrence. Chronic abdominal pain, lower gastrointestinal bleeding, and recurrent obstructive symptoms may lead to an unnecessary delay in diagnosis. This case report describes a rare cause of adult intestinal intussusception due to inverted Meckel's diverticulum. Intussusception was diagnosed on emergency ultrasound of the patient, who was successfully managed with surgery.  相似文献   
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Human pluripotent embryonic stem cells (hESCs) have great promise for research into human developmental biology, development of cell therapies for the treatment of diseases, toxicology, and drug discovery. Traditionally, undifferentiated hESCs are maintained on mouse embryonic fibroblasts (MEFs), which impede the clinical applications of hESCs. Here we have examined the long-term stability of the Japanese hESC line (KhES-1) in feeder-free culture. KhES-1 cells were cultured with MEF conditioned medium (CM) and different doses of basic fibroblast growth factor (bFGF) in six-well-plates of which the surface was coated with Matrigel. KhES-1 cells were maintained for at least 40 passages. In this culture system, the cells maintained stable proliferation rates and steadily expressed Oct-4, Nanog, and alkaline phosphatase. In addition, KhES-1 cells maintained without direct feeder contact formed embryonic bodies with expression of markers from the three germ layers. Here we demonstrated that Japanese human embryonic stem cells KhES-1 were cultured long term in a feeder-free method, while retaining pluripotency in vitro.  相似文献   
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