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411.
Effects of temperature on granulocyte preservation   总被引:1,自引:0,他引:1  
McCullough  J; Wieblen  BJ; Peterson  PK; Quie  PG 《Blood》1978,52(2):301-310
With the increasing use of granulocyte transfusion it is becoming important to determine if granulocytes can be preserved for a few days. If so, the optimum storage conditions must be identified. We studied the function in vitro of granulocytes collected as they would be for transfusion by continuous-flow centrifuge leukapheresis (CFCL) and filtration leukapheresis (FL). Granulocytes collected by CFCL maintained normal ability to phagocytose and kill bacteria after 48 hr and normal chemotaxis after 24 hr of storage at 20 degrees--24 degrees C. Neither 1 degrees--6 degrees C nor 37 degrees C were as effective in preserving chemotactic response. Agitation of the granulocyte suspension during storage caused reduced bacterial killing and chemotaxis. Granulocytes collected by FL functioned very poorly after 24 hr storage at all temperatures studied. These studies suggest that it may be possible to store CFCL granulocytes at 20 degrees--24 degrees C for 24 hr. FL granulocytes should not be stored at all.  相似文献   
412.
Ely  P; Wallace  PK; Givan  AL; Graziano  RF; Guyre  PM; Fanger  MW 《Blood》1996,87(9):3813-3821
To show that macrophages can be effectively targeted against malignant B cells, bispecific antibodies (BsAb) were constructed from two antibodies having specificity for the high-affinity Fc receptor for IgG (Fc gamma RI/CD64) and the B-cell differentiation antigens CD19 and CD37. Using a flow cytometry-based assay and confocal imaging, we show that these constructs mediated significant phagocytosis of B lymphocytes by macrophages that could be enhanced with interferon gamma (IFN gamma) and IFN gamma in combination with macrophage colony- stimulating factor. BsAb-dependent phagocytosis was triggered through Fc gamma RI and could be blocked only by using F(ab')2 fragments from the parent molecule or by cross-linking Fc gamma RI. BsAb-dependent phagocytosis was not blocked by antibodies to the other Fc receptors, Fc gamma RII and Fc gamma RIII. Because these antibody constructs bind to an epitope outside the Fc gamma RI ligand binding site, we show that autologous serum, polyclonal IgG, and monomeric IgG1 did not block BsAb- dependent phagocytosis, whereas autologous serum and the IgG fractions blocked parent molecule monoclonal antibody-dependent phagocytosis due to the avid binding of monomeric IgG to Fc gamma RI. Finally, BsAb- mediated phagocytosis was effective against the malignant B cells of patients with mantle cell lymphoma, prolymphocytic leukemia, and chronic lymphocytic leukemia. Based on these studies, we propose that BsAbs may provide an effective means of immunomodulation for patients with B-cell malignancies.  相似文献   
413.
Nanoparticle research is currently an area of intense scientific interest due to a wide variety of potential applications. Human beings have been exposed to airborne nanosized particles throughout their evolutionary stages, and such exposures have increased dramatically over the last century. Nanoparticle can modify the physicochemical properties of the material as well as create the opportunity for increased uptake and interaction with biological tissues through inhalation, ingestion, and injection. This combination of effects can generate adverse biological effects in living cells. Nanoparticles have proved toxic to human once in the blood stream, nanoparticles, spleen, bone marrow and nervous system can be transported around the body and be taken up by organs tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death. Unlike larger particles, nanoparticles may be taken up by cell mitochondria and the cell nucleus studies demonstrate the potential for nanoparticles to cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death. Size is therefore a key factor in determining the potential toxicity of a particle. How these nanoparticles behave inside the body is still a major question that needs to be resolved. There is a responsibility to test and optimize these new nanomaterials early during the development process to eliminate or ameliorate identified toxic characteristics.  相似文献   
414.
ObjectiveTo analyze the larvicidal effect of the aerial extracts of Ammannia baccifera on two important mosquito species, Aedes aegypti and Culex quinquefasciatus.MethodsThe larval mortality of fourth instar larvae of A. aegypti and C. quinquefasciatus after 24h and 48h of treatment were observed separately in control 50, 100, 150, 200, 250, 300, 350, 400, 450 and 500 mg/L concentrations of the aerial extracts (methanol, ethyl acetate, chloroform) of A. baccifera.ResultsBased on the probit analysis, the 24h and 48h aerial methanol extract of A. baccifera LC50value of C. quinquefasciatus was found to be in 164.00 mg/L and 107.00 mg/L and LC90values for C. quinquefasciatus was found be in 310.00 and 261.00 mg/L. The 24h and 48h aerial part of methanol extract of A. baccifera LC50value of A. aegypti was found be in 226.00 mg/L and 186.00 mg/L and LC90values was found be in 476.00 and 309.00 mg/L.ConclusionsThe results indicate that the A. baccifera could be effectively used for the control of mosquito larvae and the possibility of exploiting for the development of commercial larvicides a plant widely occurring in India.  相似文献   
415.
SUMMARY A 64-year-old female presented with episodes of small bowel obstruction. Ultrasound and barium meal showed a polypoidal lesion in the proximal segment of small bowel. The patient underwent emergency surgery because of signs of impending acute intestinal obstruction. Pathology showed characteristic features of an inflammatory fibroid polyp (IFP) which is an important though rare benign cause of small bowel obstruction. We document clinical and pathological aspects of this case.  相似文献   
416.
Optimal management of patients with IBD requires a multidisciplinary approach involving primary care physicians, gastroenterologists, surgeons, radiologists, and nutritionists. The rapidly evolving medical armamentarium promises better quality of life for patients afflicted with these complex, chronic diseases. It is expected that future development of biologic agents will add to the therapeutic options, although it may complicate treatment algorithms. Surgical advancements, particularly in ileoanal anastomosis and bowel preservation by strictureplasty, have improved outcome dramatically. The focus on development of new therapies and refinement of older ones demands a constant attention to the latest peer-reviewed literature and that the clinician keep abreast of the various advancements that have been summarized here.  相似文献   
417.
Glomerular function of neonates (25 full term and equal number of preterm neonates) at birth, on day seven and day fourteen were estimated by endogenous Creatinine clearance (CCr). The Preterm were divided into three groups viz. Group I (Gestation age (GA) 30-32 weeks), Group II (GA 33-34 weeks) and Group III (GA 35-36 weeks). Group IV consisted of 25 term neonates. Serum creatinine (in mg/dl) in all the groups of preterm ranged from 0.92 ± 0.153 to 1.204 ± 0.154 and in term neonate from 0.562 ± 0.175 to 1.148 ± 0.247 showing that the levels were inversely proportional to the period of gestation. Besides the Serum Creatinine levels in all groups of Preterm as well as term neonates were found to fall significantly (p < 0.001) during the first and second week. Glomerular filtration rate (GFR) in Group I were 16.603 ± 2.519, 19.786 ± 2.078 and 23.720 ± 2320 on day one, seven and fourteen respectively showing progressive improvement during the first two weeks. The GFRs were also found to be directly proportional to the GA. In addition the levels of GFR were found increasing significantly during the second week compared to that on day seven in all the groups of preterm neonates. GFR''s in Group I & II on all the three occasions were significantly lower (p < 0.001) than those of term counterparts, however the GFR on the first day in Group III neonates was lower than group IV, the difference was insignificant (p > 0.05). The increase in GFR in Group I on the three occasions was linear but insignificant (p > 0.05). The rise was more rapid & significant (p < 0.001) during the second week in Groups II & III. On the contrary the rate of improvement of GFR in full terms was quite rapid during the first week and gradual over the second week of life.KEY WORDS: GFR preterm & term neonates, Serum creatinine  相似文献   
418.

Background:

Femoral neck fractures are treated either by internal fixation or arthroplasty. Usually, cannulated cancellous screws are used for osteosynthesis of fracture neck of femur. The bone impregnated hip screw (BIHS) is an alternative implant, where osteosyntehsis is required in femoral neck fracture.

Materials and Methods:

The BIHS is a hollow screw with thread diameter 8.3 mm, shank diameter 6.5 mm and wall thickness 2.2 mm and holes in the shaft of the screw with diameter 2 mm, placed in a staggered fashion. Biomechanical and animal experimental studies were done. Clinical study was done in two phases: Phase 1 in a group of volunteers, only with BIHS was used in a pilot study and phase 2 comparative study was done in a group with AO cannulated screws and the other group treated with BIHS.

Results:

In the phase 1 study, out of 15 patients, only one patient had delayed union. In phase 2, there were 78 patients, 44 patients in BIHS showed early union, compared to the rest 34 cases of AO cannulated screws Out of 44 patients with BIHS, 41 patients had an excellent outcome, 2 had nonunions and one implant breakage was noted.

Conclusions:

Bone impregnated hip screw has shown to provide early solid union since it incorporates the biomechanical principles and also increases the osteogenic potential and hence, found superior to conventional cannulated cancellous screw.  相似文献   
419.
420.
The increased prevalence of obese, pregnant women who have a higher risk of glucose intolerance warrants the need for nutritional interventions to improve maternal glucose homeostasis. In this study, the effect of a low-glycemic load (GL) (n = 28) was compared to a high-GL (n = 34) dietary intervention during the second half of pregnancy in obese women (body mass index (BMI) > 30 or a body fat >35%). Anthropometric and metabolic parameters were assessed at baseline (20 week) and at 28 and 34 weeks gestation. For the primary outcome 3h-glucose-iAUC (3h-incremental area under the curve), mean between-group differences were non-significant at every study timepoint (p = 0.6, 0.3, and 0.8 at 20, 28, and 34 weeks, respectively) and also assessing the mean change over the study period (p = 0.6). Furthermore, there was no statistically significant difference between the two intervention groups for any of the other examined outcomes (p ≥ 0.07). In the pooled cohort, there was no significant effect of dietary GL on any metabolic or anthropometric outcome (p ≥ 0.2). A post hoc analysis comparing the study women to a cohort of overweight or obese pregnant women who received only routine care showed that the non-study women were more likely to gain excess weight (p = 0.046) and to deliver large-for-gestational-age (LGA) (p = 0.01) or macrosomic (p = 0.006) infants. Thus, a low-GL diet consumed during the last half of pregnancy did not improve pregnancy outcomes in obese women, but in comparison to non-study women, dietary counseling reduced the risk of adverse outcomes.  相似文献   
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