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51.
In this study, different positively charged niosomal formulations containing sorbitan esters, cholesterol and cetyl trimethyl ammonium bromide were prepared by film hydration method for the entrapment of autoclaved Leishmania major (ALM). Size distribution pattern and stability of niosomes were investigated by laser light scattering method and ALM encapsulation per cent was measured by the bicinchoninic acid method. Finally, the selected formulation was used for the induction of the immune response against cutaneous leishmaniasis in BALB/c mice. Size distribution curves of all the formulations followed a log-normal pattern and the mean volume diameter was in the range 7.57-15.80 μm. The mean volume diameters were significantly increased by adding Tween to Span formulations (p?相似文献   
52.
Dynamics of extraclassical surround modulation in three types of V1 neurons   总被引:1,自引:0,他引:1  
Visual stimuli outside of the classical receptive field (CRF) can influence the response of neurons in primary visual cortex (V1). While recording single units in cat, we presented drifting sinusoidal gratings in circular apertures of different sizes to investigate this extraclassical surround modulation over time. For the full 2-s stimulus time course, three types of neurons were found: 1) 68% of the cells were "suppressive," 2) 25% were "plateau" cells that showed response saturation with no suppression, and 3) the remaining 6% of cells were "facilitative." Analysis of the response dynamics revealed that at response onset, activity of one-half of facilitative cells, 70% of plateau cells, and all suppressive cells is suppressed by the surround. However, over the next 20-30 ms, surround modulation changes to stronger suppression for suppressive cells, substantial facilitation for facilitative cells, and weak facilitation for plateau cells. For all three cell types, these modulatory effects then stabilize between 100 and 200 ms from stimulus onset. Thus our findings illustrate two stages of surround modulation. Early modulation is mainly suppressive regardless of cell type and, because of rapid onset, may rely on feedforward mechanisms. Surround modulation that evolves later in time is not always suppressive, depending on cell type, and may be generated through different combinations of cortical circuits. Additional analysis of modulation throughout the cortical column suggests the possibility that the larger excitatory fields of facilitative cells, primarily found in infragranular layers, may contribute to the second stage of suppression through intracolumnar circuitry.  相似文献   
53.
Neuropsychologists routinely give effort tests, such as the Test of Memory Malingering (TOMM). When a person fails one of these tests, the clinician must try to determine whether the poor performance was due to suboptimal effort or to chronic pain, depression, or other problems. Participants were 54 community-dwelling patients who met American College of Rheumatology criteria for fibromyalgia (FM). In addition to the TOMM, they completed the Beck Depression Inventory-Second Edition, Multidimensional Pain Inventory-Version 1, Oswestry Disability Index-2.0, British Columbia Cognitive Complaints Inventory, and the Fibromyalgia Impact Questionnaire. The majority endorsed at least mild levels of depressive symptoms (72%), and 22% endorsed "severe" levels of depression. The average scores on the TOMM were 48.8 (SD = 1.9, range = 40-50) for Trial 1, 49.8 (SD = 0.5, range = 48-50) for Trial 2, and 49.6 (SD = 0.9, range = 45-50) for Retention. Despite relatively high levels of self-reported depression, chronic pain, and disability, not a single patient failed the TOMM. In this study, the TOMM was not affected by chronic pain, depression, or both.  相似文献   
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There are several studies done to show the comparability of laser scaling and root planing with routine methods. The most suitable wavelengths for such an application are reported as 2,940 and 2,780 nm. The superficial interactions of the current wavelength with root surface is investigated in this study to compare the crater and crack formation during the procedures between ultrasound and Er,Cr:yttrium-scandium-gallium garnet (YSGG; 2,780 nm) laser-treated teeth. Thirty human teeth with calculus on their root surface, which were extracted because of the severe periodontitis, were selected for this interventional in vitro study. Calculus area were divided into two equal parts: One of them was prepared for Er,Cr:YSGG (Biolase, Waterlase, USA) laser irradiation and the other one for ultrasound treatment (Dentsply cavitron, DENTSPLY International, USA). The Er,Cr:YSGG laser was specified as follows: pulse energy = 50 mJ, power = 1 W, wavelength = 2,780 nm, pulse repetition rate = 20 pulse per seconds, tip length = 6 mm, and tip diameter = 600 microm. Nineteen of the laser samples (95%) and eight of ultrasound ones (40%) out of 20 samples in each group had craters showing a statistical significant difference (p < 0.001). The number and depth of these craters are also evaluated. Thirteen samples of the laser cases (65%) and all samples of the ultrasound group showed cracks with significant differences (p = 0.008). In addition, the number and width of cracks in both groups are reported. As a general conclusion, the laser-treated samples show more craters but less cracks.  相似文献   
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Twelve strains of gram-negative, nonfermenting rods recovered mainly from septicemic patients were studied using conventional and molecular methods. The phenotypic profiles of these strains most closely resembled Psychrobacter phenylpyruvicus. They produced catalase, oxidase, urease, and H(2)S (lead acetate paper) but did not produce indole, reduce nitrate or nitrite, or hydrolyze gelatin or esculin. No acid production was observed in a King's oxidation-fermentation base containing d-glucose, d-xylose, d-mannitol, sucrose, lactose, or maltose. All strains were nonmotile and nonpigmented. Most strains produced green discoloration on blood agar. All strains grew at 25 degrees C and 35 degrees C and most grew on MacConkey agar. They shared a common cellular fatty acid (CFA) profile characterized by large amounts (56% to 90%) of 18:1omega7c and the presence of 3-OH-10:0, 16:1omega7c, 16:0, and 19:0cycomega8c that overall was most similar to that of Rhodobacter species but was quite distinct from that of P. phenylpyruvicus. The MICs for most beta-lactams, fluoroquinolones, aminoglycosides, and carbapenems were low. MICs for aztreonam and piperacillin were higher, with MICs for some strains of > 64 mg/liter and > 128 mg/liter, respectively. Polyphasic analysis of these strains, including morphological, biochemical, CFA composition, DNA-DNA hybridization, 16S rRNA gene sequencing, and percent guanine-plus-cytosine (G+C) content analysis, demonstrated that these strains and Rhodobacter massiliensis represent a new genus, "Haematobacter" (proposed name), with the species H. missouriensis (type strain H1892(T) = CCUG 52307(T) = CIP 109176(T)) and H. massiliensis comb. nov. (type strain Framboise(T) = CCUG 47968(T) = CIP 107725(T)) and an unnamed genomospecies.  相似文献   
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Study Type – Therapy (case series) Level of Evidence 4 What's known on the subject? and What does the study add? Laparoscopic pyeloplasty has replaced open pyeloplasty as the new standard of care and we, among others, have even proven its applicability to redo surgery. The focus is now on limiting morbidity. One technical modification to this end is transmesocolic (TM) exposure of the PUJ. This randomized study pinpoints the objective benefits of TM exposure of the PUJ compared with standard colon reflection, and its results showed a 23% conservation in operating time.

OBJECTIVE

  • ? To compare the efficacy and safety of colon‐reflecting (CR) and transmesocolic (TM) laparoscopic pyeloplasty approaches in a prospective randomized non‐selective setting.

PATIENTS AND METHODS

  • ? Excluding only those patients with a history of abdominal surgery, all consenting patients scheduled for laparoscopic pyeloplasty of left‐sided pelvi‐ureteric junction (PUJ) obstruction between December 2004 and November 2007 were randomized into one of two groups: laparoscopic pyeloplasty using the standard CR approach or laparoscopic pyeloplasty through the TM aperture.
  • ? All patients underwent dismembered repair by a single expert and were followed by diuretic renogram and urography at 4 months postoperatively and by annual diuretic renogram thereafter.
  • ? Four discrete task phases were timed for comparison: trochar to PUJ, dismembering and spatulation, stenting and anastomosis.

RESULTS

  • ? Sixty‐four patients were randomized into two groups, TM or CR, with 32 patients in each.
  • ? The groups were similar, with no significant difference in sex, age, initial renal function or body mass index. Forty‐seven patients were ≤15 years old.
  • ? The mean (sd ) operating time was 23% shorter in the TM group, owing mostly to the much shorter trochar to PUJ phase (5.0 [3.2] min in the TM group vs 35.8 [10.3] in the CR group; P < 0.001). The mean hospitalization time was shorter in the TM group than in the CR group (2.9 vs 3.6 days; P < 0.001).
  • ? Thirty‐one of 32 patients in each group (96.9%) achieved a durable cure.

CONCLUSION

  • ? Transmesocolic exposure of left‐sided PUJ obstruction is superior to standard CR exposure, in that it saves anaesthesia time, hospitalization time and has lower morbidity with no compromise in efficiency, and could be considered as the new standard approach.
  相似文献   
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