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91.
OBJECTIVE: Maternal vaccination may become a central strategy in the prevention of early-onset group B Streptococcal sepsis. Unlike earlier group B streptococcal polysaccharide vaccines that were poorly immunogenic, newer vaccines conjugated to tetanus toxoid have been developed and have improved immunogenicity. We sought to evaluate a conjugated vaccine using our rabbit model of ascending infection. STUDY DESIGN: Rabbit does were randomized to receive either conjugated group B streptococcal type Ia (Ia-tetanus toxoid) or conjugated group B streptococcal type III (III-tetanus toxoid) vaccine. Does were vaccinated 7 days before conception and 7 and 21 days after conception. On days 28 to 30 of a 30-day gestation, does were inoculated intracervically with 10(6) colony-forming units of type Ia group B Streptococcus. Labor was induced if does were undelivered after 72 hours. Does were observed up to 7 days after inoculation. Offspring were observed up to 4 days. We obtained maternal cultures from the uterus, peritoneum, and blood and offspring cultures from the mouth, anus, and blood. Antibody levels were also determined. RESULTS: Offspring survival was significantly improved in the group receiving Ia-tetanus toxoid (P =.047). Outcomes such as maternal sepsis and severe illness, although not reaching statistical significance, showed a trend toward improved outcomes in the Ia-tetanus toxoid group. CONCLUSIONS: This is the first study to evaluate the conjugated group B streptococcal vaccine by using any model of ascending infection. The Ia-tetanus toxoid vaccine led to improved survival and was immunogenic but fell short of its expected efficacy in preventing ascending group B streptococcal disease under these experimental conditions.  相似文献   
92.
Nilsson  H; Torndal  UB; Eriksson  LC 《Carcinogenesis》1997,18(12):2447-2451
The metabolism of inositol 1,4,5-trisphosphate and inositol 1,3,4,5- tetrakisphosphate in homogenates and sub-fractions from normal rat liver and premalignant liver nodules was investigated. The activities of 5-phosphatase, expressed as pmol converted substrate per minute and mg protein, were equal when using the two substrates, and did not differ between normal and nodular homogenates. Subcellular fractions were purified by sequential steps of differential centrifugation and density gradient fractionation procedures. The total phosphatase activity was found to be distributed between cytosol (15%) and membraneous fractions (75%), with most of the enzyme activity residing in the plasma membranes. A doubling of phosphatase specific activity was seen in the nodular low density membrane fraction, containing Golgi apparatus and endosomes, as compared with normal liver. Inositol 1,4,5- trisphosphate 3-kinase activity was found to be exclusively cytosolic. No difference in this enzyme was seen between the two tissue types studied. Vasopressin (0.2 or 2 microM) had no effect either on phosphatase or kinase activity. The compartmentalization of inositol polyphosphate 5-phosphatase activity presents a possible explanation of earlier findings that premalignant liver tissue was able to respond with inositol 1,4,5-trisphosphate, but not inositol 1,3,4,5- tetrakisphosphate formation after agonist stimulation.   相似文献   
93.
卢涛  高天文  刘玉峰  李春英  孙林潮 《医学争鸣》2001,22(12):1147-1147
0 引言 白癜风患者免疫紊乱 ,黑素细胞 (melanocyte,MC)异体移植有可能不被排斥 ,治疗如成功将有很大临床前景 [1 ] .探索同种异体黑素细胞移植后的效果很有意义 .1 病例报告 女 ,2 7岁 ,确诊白癜风 (稳定期 ) ,患者皮肤自幼出现色素脱失斑 ,逐渐增多扩大 . 1996年外用“敏白灵”,前2 mo有效 . 1999- 0 7外用补骨酯酊 ,日服 5 g· L- 1 硫酸铜 10m L和中药 1剂 ,转移因子 4m L ,sc,1· 2 d- 1 .皮损缩小 ,4mo后稳定 .用健康男青年环切的包皮培养 MC,第 4代大约80 %融合时 ,用 2 .5 g· L- 1 胰酶消化 5 min,加入含 2 0 0 g·L- 1小…  相似文献   
94.
Liver surgery for the treatment of colorectal liver metastases is the standard treatment in a dynamic surgical field with many variables that should be considered in a curative intent scenario. Hepatectomy for colorectal liver metastases has undergone constant changes over the last 30 years, including indications until the need for rescue procedures of recurrent and advanced diseases as well as minimally invasive surgery. These advancements in liver surgery have not only resulted from overall improvements in the surgical field but have also resulted from a better understanding of the biological behavior of the disease, liver regeneration, and homeostasis during and after surgery.Improvements in anesthesiology, intensive care medicine, radiology, and surgical devices have correlated with further advancements of hepatectomies. Moreover,changes are still forthcoming, and both fields of augmented reality and artificial intelligence will likely have future contributions in this field in regard to both diagnoses and the planning of procedures. The aim of this editorial is to emphasize several aspects that have contributed to the paradigm shifts in colorectal liver metastases surgery over the last three decades as well as to discuss the factors concerning patient selection and the technical aspects of liver surgery. Finally, this editorial will highlight the promising new features of this surgery for diagnoses and treatments in this field.  相似文献   
95.

Purpose

To demonstrate rates of successful filter conversion and 6-month major device-related adverse events in subjects with converted caval filters.

Materials and Methods

An investigational device exemption multicenter, prospective, single-arm study was performed at 11 sites enrolling 149 patients. The VenaTech Convertible Vena Cava Filter (B. Braun Interventional Systems, Inc, Bethlehem, Pennsylvania) was implanted in 149 patients with venous thromboembolism and contraindication to or failure of anticoagulation (n = 119), with high-risk trauma (n = 14), and for surgical prophylaxis (n = 16). When the patient was no longer at risk for pulmonary embolism as determined by clinical assessment, an attempt at filter conversion was made. Follow-up of converted patients (n = 93) was conducted at 30 days, 3 months, and 6 months after conversion. Patients who did not undergo a conversion attempt (n = 53) had follow-up at 6 months after implant.

Results

All implants were successful. One 7-day migration to the right atrium required surgical removal. Technical success rate for filter conversion was 92.7% (89/96). Mean time from placement to conversion was 130.7 days (range, 15–391 d). No major conversion-related events were reported. The mean conversion procedure time was 30.7 minutes (range, 7–135 min). There were 89 converted and 32 unconverted patients who completed 6-month follow-up with no delayed complications.

Conclusions

The VenaTech Convertible filter has a high conversion rate and low 6-month device-related adverse event rate. Further studies are necessary to determine long-term safety and efficacy in both converted and unconverted patients.  相似文献   
96.
Rectal adenocarcinoma is an important cause of cancer-related deaths worldwide, and key anatomic differences between the rectum and the colon have significant implications for management of rectal cancer. Many advances have been made in the diagnosis and management of rectal cancer. These include clinical staging with imaging studies such as endorectal ultrasound and pelvic magnetic resonance imaging, operative approaches such as transanal endoscopic microsurgery and laparoscopic and robotic assisted proctectomy, as well as refined neoadjuvant and adjuvant therapies. For stage Ⅱ and Ⅲ rectal cancers, combined chemoradiotherapy offers the lowest rates of local and distant relapse, and is delivered neoadjuvantly to improve tolerability and optimize surgical outcomes, particularly when sphincter-sparing surgery is an endpoint. The goal in rectal cancer treatment is to optimize diseasefree and overall survival while minimizing the risk of local recurrence and toxicity from both radiation and systemic therapy. Optimal patient outcomes depend on multidisciplinary involvement for tailored therapy. The successful management of rectal cancer requires a multidisciplinary approach, with the involvement of enterostomal nurses, gastroenterologists, medical and radiation oncologists, radiologists, pathologists and surgeons. The identification of patients who are candidates for combined modality treatment is particularly useful to optimize outcomes. This article provides an overview of the diagnosis, staging and multimodal therapy of patients with rectal cancer for primary care providers.  相似文献   
97.

Introduction

Treatment options for patients with fecal incontinence (FI) are limited, and surgical treatments can be associated with high rates of infection and other complications. One treatment, sacral nerve stimulation (SNS), is approved for FI in Europe. A large multicenter trial was conducted in North America and Australia to assess the efficacy of SNS in patients with chronic fecal incontinence. The aim of this report was to analyze the infectious complication rates in that trial.

Methods

Adult patients with a history of chronic fecal incontinence were enrolled into this study. Those patients who fulfilled study inclusion/exclusion criteria and demonstrated greater than two FI episodes per week underwent a 2-week test phase of SNS. Patients who showed a ≥50% reduction in incontinent episodes and/or days per week underwent chronic stimulator implantation. Adverse events were reported to the sponsor by investigators at each study site and then coded. All events coded as implant site infection were included in this analysis.

Results

One hundred twenty subjects (92% female, 60.5?±?12.5 years old) received a chronically implanted InterStim® Therapy device (Medtronic, Minneapolis, MN, USA). Patients were followed for an average of 28 months (range 2.2-69.5). Thirteen of the 120 implanted subjects (10.8%) reported infection after the chronic system implant. One infection spontaneously resolved and five were successfully treated with antibiotics. Seven infections (5.8%) required surgical intervention, with infections in six patients requiring full permanent device explantation. The duration of the test stimulation implant procedure was similar between the infected group (74 min) and the non-infected group (74 min). The average duration of the chronic neurostimulator implant procedure was also similar between the infected (39 min) and non-infected group (37 min). Nine infections occurred within a month of chronic system implant and the remaining four infections occurred more than a year from implantation. While the majority (7/9) of the early infections was successfully treated with observation, antibiotics, or system replacement, all four of the late infections resulted in permanent system explantation.

Conclusion

SNS for FI resulted in a relatively low infection rate. This finding is especially important because the only other Food and Drug Administration-approved treatment for end-stage FI, the artificial bowel sphincter, reports a much higher rate. Combined with its published high therapeutic success rate, this treatment has a positive risk/benefit profile.  相似文献   
98.

Background  

Allograft bone used in joint replacement surgery can additionally serve as a carrier for antibiotics and serve as a prophylaxis against infections. However, in vitro dose-response curves for bone chips impregnated with different kinds of antibiotics are not available. In addition, while it would be desirable to add the antibiotics to allograft bone chips before these are stored in a bone bank, the effects of different storage temperatures on antibiotics are unknown.  相似文献   
99.

BACKGROUND:

Because of their proximity to the pulmonary artery or vein, hilar lymph nodes are routinely biopsied with endobronchial or endoscopic ultrasonography (EUS)‐guided fine‐needle aspiration biopsy (FNAB). Computed tomography (CT)‐guided percutaneous needle biopsy (PNB) allows the operator to acquire a larger core needle biopsy (CNB) when initial samples are inconclusive, when the suspected disease is not optimally diagnosed with FNAB, or when biomarkers are required. The purpose of this study was to retrospectively evaluate the sensitivity and accuracy of CT‐guided PNB in patients with hilar adenopathy.

METHODS:

The authors identified 80 patients who underwent 81 CT‐guided PNBs of pulmonary hilar lesions from October 2002 through December 2006 and retrospectively reviewed their medical and imaging records. The PNB sensitivity and accuracy were calculated in each case, and each case was reviewed for complications, including pneumothorax and subsequent thoracostomy tube insertion.

RESULTS:

PNB included FNAB and CNB in 81 (100%) and 14 (17%) procedures, respectively. Data on 69 PNB specimens (67 FNAB specimens and 13 CNB specimens) were available for statistical analysis. Overall, PNB had a sensitivity of 91.4% (95% confidence interval [CI], 81.0%‐97.1%) and an accuracy rate of 92.8% (95% CI, 83.9%‐97.1%). Pneumothoraxes occurred in 39 patients (48%), 26 (32%) of whom required thoracostomy tube insertion.

CONCLUSIONS:

CT‐guided PNB of pulmonary hilar lesions has high sensitivity and accuracy and represents a viable alternative for endobronchial ultrasound‐ or EUS‐guided FNAB when larger biopsy samples are required for diagnosis or biomarker analysis. However, the procedure can result in high rates of pneumothorax. Cancer 2010. © 2010 American Cancer Society.  相似文献   
100.
OBJECTIVE: The objective of our study was to evaluate our experience with transcatheter proximal (i.e., main) splenic artery embolization (TPSAE) in the nonsurgical management of patients with grade III-V splenic injuries, according to the American Association for the Surgery of Trauma (AAST) guidelines, and patients with splenic injuries associated with CT evidence of active contrast extravasation or blush (or cases meeting both criteria). MATERIALS AND METHODS: The records of patients with traumatic splenic injuries admitted during a 52-month period were retrospectively reviewed for patient age and sex, mechanism of injury, injury severity score (ISS), RBC transfusion requirements, AAST splenic injury CT grade, presence of active contrast extravasation or blush on CT examination, and amount of hemoperitoneum on CT examination. Demographics, CT findings, transfusion requirements, and outcome were compared using the Student's t test or chi-square test in patients undergoing standard nonoperative management and nonoperative management TPSAE-that is, TPSAE followed by nonoperative management. RESULTS: Of the 79 identified patients with splenic trauma, 67 were managed nonoperatively. Thirty-seven patients (28 men, nine women; mean age, 40 years; mean ISS, 28.8) underwent nonoperative management TPSAE and 30 patients (27 men, three women; mean age, 37 years; mean ISS, 25.1) underwent nonoperative management. Age, sex, and ISS were not significantly different between the two groups. TPSAE was always technically feasible. Splenic injuries were significantly more severe in the nonoperative management TPSAE group than in the nonoperative management group with respect to the mean splenic injury AAST CT grade (3.7 vs 2, respectively; p < 0.0001), active contrast extravasation or blush (38% [14/37] vs 3% [1/30], respectively; p = 0.0005), and hemoperitoneum grade (1.6 vs 0.8, respectively; p = 0.0006). Secondary splenectomy rate was lower in the nonoperative management TPSAE group (2.7% [1/37] vs 10% [3/30]). No procedure-related complications were encountered during early and delayed clinical follow-up. CONCLUSION: TPSAE is a feasible and safe adjunct to observation in the nonoperative management of severe traumatic splenic injuries. The secondary splenectomy rate using nonoperative management TPSAE (2.7%) is among the lowest reported despite a selection of severe injuries.  相似文献   
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