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Digestive Diseases and Sciences - To determine whether the presence of portal vein thrombosis (PVT) where venous flow within the liver may be altered may delay the diagnosis of HCC and be...  相似文献   
3.
Gangliosides of cultured astroglia   总被引:3,自引:0,他引:3  
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type.  相似文献   
4.
Background: Anterior segment findings in AIDS patients presenting with cytomegalovirus (CMV) retinitis have not been specifically addressed in the American literature. Methods: Our study evaluated 21 AIDS patients with CMV retinitis. Results: Nineteen (90%) of these patients exhibited corneal endothelial deposits concurrent with CMV retinitis. The endothelial deposits were microscopic, opaque, linear flecks arranged in a reticular-like fashion. Of 42 eyes evaluated, 32 (76%) demonstrated active CMV retinitis. Corneal endothelial deposits were noted in 26 (81%) of the 32 eyes with retinitis. These corneal endothelial deposits were absent in the eyes which did not have CMV retinitis. Conclusion: Meticulous examination of the retina of an HIV-positive or AIDS patient who presents with reticularly arranged, linear, flecked corneal endothelial deposits should be performed to ensure that the diagnosis of CMV retinitis can be ruled out.  相似文献   
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6.
The aim of this study was to determine specific pattern of port site microbial colonisation, sensitivity and resistance to different antibiotics of bacteria isolated from port site infection (PSI) in low risk patients after elective laparoscopic cholecystectomy in surgical wards at tertiary care hospital of Kashmir. This is a prospective study. The study included 675 consecutive patients of postoperative PSI after elective laparoscopic cholecystectomy for symptomatic cholelithiasis over a period of 12 months. Culture swabs were taken from port sites with signs of PSI and transported to the microbiology laboratory. The positive swab cultures were subjected to antibiotic susceptibility test. The data obtained was analysed by using appropriate statistical analytical tests. The incidence of PSI after elective laparoscopic cholecystectomy is 6·7%. The commonest organism responsible for PSI is pseudomonas, 19 (42·2%) cases. Most of the strains of organisms isolated were resistant to commonly used antibiotics in the hospital,pseudomonas was found 100% resistant to the combination of ampicillin + sulbactum and ceftriaxone and it was sensitive to imipenem, amikacin and vancomycin in 89·47,57 and 52·63% of cases respectively. Our study will be helpful in choosing effective empirical prophylactic antibiotic therapy in cases of elective laparoscopiccholecystectomy and will have a great impact on morbidity and mortality in them because of PSI.  相似文献   
7.
Context: Azadirachta indica A. Juss. (Meliaceaes) leaves have been used traditionally to treat swelling and rheumatism in Indian cultures.

Objective: To fractionate A. indica leaf extracts using bioactivity guided manner for identification of the active anti-inflammatory principles.

Materials and methods: Polarity-gradient sequential extracts (petroleum ether, chloroform, methanol, and water) of A. indica leaves were screened for their anti-inflammatory potential using the carrageenan-induced rat paw edema model (1?g/kg). The chloroform extract was sequentially fractionated to obtain n-hexane (F-1), n-hexane-chloroform (F-2), and chloroform (F-3) fractions and their inhibitory effect on rat paw edema was evaluated (500?mg/kg). Inhibitory effect of F-2 on granuloma formation, plasma interleukin (IL-1), and tumor necrosis factor (TNF-α) was assessed at the doses of 100, 200, and 400?mg/kg using the cotton pellet assay in rats. Three sub-fractions (SF-1, SF-2, and SF-3) were obtained upon chromatography of F-2, and their inhibitory effect on cyclooxygenase was assessed at 200?µg/mL concentration. The sub-fractions were subjected to gas chromatography–mass spectrometry (GC-MS).

Results: All the extracts showed significant anti-inflammatory effect; however, chloroform extract was the most effective against paw edema (53.25% inhibition). The three fractions of chloroform extract showed significant effect, while F-2 being the most potent (51.02%). F-2 demonstrated dose-dependent inhibition of granuloma and cytokines. Interestingly, all the sub-fractions of F-2 inhibited COX-1 and COX-2 with almost equal potential. GC-MS revealed that chemically the sub-fractions were totally different from each other.

Discussion and conclusion: Anti-inflammatory effect of A. indica is a result of cumulative and synergistic effects of diversified constituents with varying polarities that collectively exert the effect via suppression of cyclo-oxygenases and cytokines (IL-1 and TNF-α).  相似文献   
8.
Hematological malignancies express high levels of CD47 as a mechanism of immune evasion. CD47-SIRPα triggers a cascade of events that inhibit phagocytosis. Preclinical research supports several models of antibody-mediated blockade of CD47-SIRPα resulting in cell death signaling, phagocytosis of cells bearing stress signals, and priming of tumor-specific T cell responses. Four different antibody molecules designed to target the CD47-SIRPα interaction in malignancy are currently being studied in clinical trials: Hu5F9-G4, CC-90002, TTI-621, and ALX-148. Hu5F9-G4, a humanized anti-CD47 blocking antibody is currently being studied in four different Phase I trials. These studies may lay the groundwork for therapeutic bispecific antibodies. Bispecific antibody (CD20-CD47SL) fusion of anti-CD20 (Rituximab) and anti-CD47 also demonstrated a synergistic effect against lymphoma in preclinical models. This review summarizes the large body of preclinical evidence and emerging clinical data supporting the use of antibodies designed to target the CD47-SIRPα interaction in leukemia, lymphoma and multiple myeloma.  相似文献   
9.

Background

Laparoscopic cholecystectomy (LC) is the standard operative intervention for gallbladder disease. Complications may necessitate conversion to an open cholecystectomy (OC). This study aims to determine the cost-consequences of laparoscopic-to-open conversion using a nationally-representative sample.

Methods

Using the National Inpatient Sample (2007–2011), adult patients undergoing emergent LC were identified. Patients undergoing secondary-conversion to OC were subsequently identified. Multivariable regression analyses, accounting for differences in propensity-quintile, mortality, length of stay, and hospital-level factors were then performed to assess for differences in the odds of conversion and total predicted mean costs per index-hospitalization.

Results

Of 225,805 observations, conversion to open occurred in 1.86% (n?=?4203) of cases. Increased age, African-American ethnicity, public-insurance and teaching-hospital status were associated with a higher likelihood of conversion (p?<?0.05) after risk-adjustment. Risk-adjusted odds of conversion increased by 34% (95%CI:1.33–1.36) for each day surgery was delayed. Risk-adjusted costs, were 259% higher (absolute-difference $23,358,p?<?0.05) with conversion. Mortality was higher amongst patients undergoing conversion to open (4.98% vs 0.34%,p?<?0.001).

Conclusion

Patients undergoing conversion from laparoscopic to open cholecystectomy are at an increased risk of receiving disparate care and increased mortality.  相似文献   
10.
This paper describes the clinical treatment of two cases presented by the recipient of the 2015 Bi-collegiate Membership in Orthodontics John Kay Williams Gold Medal of the Royal College of Surgeons of England and Glasgow. The first case describes the management of an 11-year-old male with a class II Division 1 malocclusion with a 9?mm overjet complicated by an upper anterior odontome and moderate upper arch crowding. The second case describes a 14-year-old female with a class III malocclusion with a reverse overjet complicated by moderate lower arch crowding and previously removed upper permanent canines.  相似文献   
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