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71.
72.
The nucleocapsid (N) protein of SARS-coronavirus (SARS-CoV) is the key protein for the formation of the helical nucleocapsid during virion assembly. This protein is believed to be more conserved than other proteins of the virus, such as spike and membrane glycoprotein. In this study, the N protein of SARS-CoV was expressed in Escherichia coli DHSalpha and identified with pooled sera from patients in the convalescence phase of SARS. A plasmid pCI-N, encoding the full-length N gene of SARS-CoV, was constructed. Expression of the N protein was observed in COS1 cells following transfection with pCI-N. The immune responses induced by intramuscular immunization with pCI-N were evaluated in a murine model. Serum anti-N immunoglobutins and splenocytes proliferative responses against N protein were observed in immunized BALB/c mice. The major immunoglobulin G subclass recognizing N protein was immunoglobulin G2a, and stimulated splenocytes secreted high levels of gamma interferon and IL-2 in response to N protein. More importantly, the immunized mice produced strong delayed-type hypersensitivity (DTH) and CD^8+ CTL responses to N protein.  相似文献   
73.
PT-9K/129G, a nontoxic mutant of pertussis toxin (PT) obtained by genetic manipulation, has been shown in animal models to be a promising candidate for new vaccines against whooping cough. To assess the safety and the immunogenicity of PT-9K/129G in humans, a pilot study has been performed in adult volunteers. The protein was found to be safe, capable of inducing high titers of toxin-neutralizing antibodies, and capable of generating immunological memory. In fact, vaccination caused an increase of cell-mediated response to PT, PT-9K/129G, S1 subunit, and B oligomer, indicating that memory T cells are induced by the vaccine. Since PT-9K/129G is mitogenic for T lymphocytes in vitro, it was investigated whether this activity is also present in vivo. No variation was observed in the proportion of T cells (CD3+), T helper cells (CD4+), and cytotoxic T cells (CD8+), as well as in that of other lymphoid populations, by FACS analysis. Interestingly, no thorough correlation was found between humoral and cellular responses. In one case, a very high cellular response was present in absence of detectable antibodies, suggesting that the antibody response, which is the only parameter measured in most clinical trials, may not give a complete picture of the response induced by a vaccine.  相似文献   
74.

Background

The field of laparoscopy has undergone several changes to improve the morbidity and cosmesis of laparoscopic surgery. The robotic single-site surgery is the inevitable hybridization of robotic technology with laparoendoscopic single-site surgery.

Methods

Perioperative information of 12 robotic single-site hysterectomies (R-SSH) were collected to evaluate the surgical feasibility and the possible influence of the body mass index (BMI) and the uterine weight on operative times.

Results

The mean operative time was 85 ± 33 min (range, 355 to 149 min), the mean docking time was 9 ± 3 min, and the mean console time was 76 ± 33 min. The mean blood loss was 80 ± 18 mL, and the median weight of resected uteri was 220 ± 45 g. No serious postoperative complications occurred. The CUSUM learning curve was observed to consist of two different phases: phase 1 (the initial 6 cases) and phase 2 (the last 6 cases) with significant reduction in operative and console time observed between the two phases. For BMI, no correlation was found with operative times, console times, and docking times, and no correlation was found between uterine weight and operative time.

Conclusions

This series, identifying two different phases of the learning curve and suggesting that the initial learning phase for the procedure can be achieved after six cases, confirms the feasibility and safety of a robotic approach for single-site hysterectomy. However, the limits of this study mainly rely on the limited casuistic and short follow-up, although the preliminary results appear promising. Larger series and prospective studies comparing R-SSH hysterectomy with standard robotic multiport hysterectomy are necessary to define properly the role of this innovative surgical technique.  相似文献   
75.
We describe two type 2 diabetic patients with unilateral emphysematous pyelonephritis who responded to medical treatment alone. Escherichia coli was isolated in both patients. The presence of gas was confirmed early by ultrasound and CT scan of abdomen. Following treatment, good functional recovery was demonstrable in the affected kidneys by isotope renogram. We stress the need for early diagnosis of this condition and aggressive treatment with broad spectrum antibiotics.  相似文献   
76.
77.
Calcium phosphates (CaP) are the main constituents of the mineral phase in bones and teeth and, along with calcium silicates and bioactive glasses, have been extensively investigated in remineralization of enamel and dentin. When used as ion-releasing fillers in resin-based materials, they could contribute to extend the service life of adhesive restorations, remineralize caries-affected dentin or prevent caries lesions under sealants and orthodontic brackets. However, the development of resin-based bioactive materials is not straightforward because of the several compositional variables involved in ion release. Also, CaP particles do not reinforce the material; therefore, if high mechanical properties are required, the ratio between CaP particles and reinforcing fillers must be observed. Several research groups have investigated how CaP phase, particle size and content, as well as resin matrix formulation affect remineralization, ion release kinetics and mechanical properties of these materials. This review presents an overview of the main findings reported in the literature.  相似文献   
78.
An imbalance between pro-angiogenic and anti-angiogenic factors is hypothesized in the pathogenesis of ovarian cystic disease. The aim of the following study was to explore the possible role of free vascular endothelial growth factor receptor 1 (sVEGFR-1), a soluble regulator of vascular endothelial growth factor (VEGF) action, in ovarian cystoadenoma, endometriomata and cystoadenocarcinoma. Forty-eight women, of whom fourteen had ovarian serous cysts, twenty-eight had stage III-IV ovarian endometriomata, and six had stage IIIB-IIIC ovarian carcinoma, were included. Sampling of serum, peritoneal and ovarian cystic fluids and of tumor tissue was performed before, during and following surgery, respectively. Levels of VEGF and sVEGFR-1 were measured in serum, peritoneal and cystic fluid. VEGF and sVEGFR-1 expression was evaluated in tumor tissue. There were no differences in serum VEGF and sVEGFR-1 levels nor in VEGF/VEGFR-1 ratio between study groups. Peritoneal fluid VEGF levels were higher in cystoadenocarcinoma patients than in endometriosis and in cystoadenoma patients, while sVEGFR-1 peritoneal fluid concentrations were significantly higher only in endometriosis-affected women. VEGF/VEGFR-1 ratio was highest in the peritoneal fluid of cancer patients with respect to the other two groups of women. Cystic fluid VEGF and VEGFR-1 concentrations were higher in endometriomata and in cystoadenocarcinomas than in cystadenomas but the VEGF/VEGFR-1 ratio was highest in cancer patients. Western blot evidenced a marked expression of VEGF and soluble VEGFR-1 in endometriosis tissue with respect to benign cyst tissue but a lower expression of both molecules, contrary to that expected, in cancer tissue. In conclusion, all in all, our data indicate that an excess of local VEGF with respect to its soluble receptor VEGFR-1 may be a key factor in the onset and maintenance of pathological neo-angiogenesis in ovarian cyst formation.  相似文献   
79.
80.

Background

Hospital-acquired infections (HAIs) result in excess morbidity, mortality, and resource consumption. Immobilized, ventilator-dependent ICU patients are at the highest risk of HAI.

Methods

Despite broad implementation of relevant bundles, HAI incidence in our neuro ICU remained high, particularly catheter-associated urinary tract infections (CAUTIs) and ventilator-associated events (VAEs). We reviewed the administrative data and nosocomial infection markers (NIMs) for all neurology and cranial neurosurgery patients admitted to our neuro ICU between January 2011 and May 2014, identified and implemented interventions, and measured effects using National Healthcare Safety Network (NHSN)-defined CAUTIs and VAEs. Interventions included (1) reviewing Foley catheter use, including indications and alternatives, and instituting daily rounds, continuously questioning the ongoing need for a catheter; (2) re-educating neuro ICU personnel in insertion and maintenance technique, introducing a new kit that simplified and standardized sterile insertion; and (3) placing a mobile CT in the neuro ICU since our patients required repeated transports for brain imaging and since we found correlations between frequencies of these transports, and both respiratory and urinary NIMS.

Results

VAEs decreased 48 %, Foley use decreased 46 %, CAUTIs decreased from 11/1000 catheter days to 6.2. Overall complication rate decreased 55 %, ICU length of stay 1.5 days, and risk-adjusted mortality 11 %.

Conclusions

Combining a multidisciplinary approach with rigorous analysis of objective data, we decreased total HAIs by 53 % over 18 months. Key drivers were decreased urinary catheter use and decreased patient transport from the ICU for imaging.
  相似文献   
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