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101.
Different poly(vinyl alcohol) (PVA)/chitosan lactate (ChL)-blended hydrogels containing nitrofurazone as a local anti-infective drug were prepared by the phase-inversion technique. The swelling degree, surface free energy, mechanical properties, and nitrofurazone release of these membranes were determined. Blood compatibility of these systems was evaluated by the open-static platelet adhesion test with whole human blood. The results showed that water absorption into the PVA/ChL membranes slowed down, governed by the rate at which the dressing interacted with the physiological fluid. Swelling degree values up to 200% were observed. The rate of release of nitrofurazone seemed to depend on the ChL percentage on the blend as well as the pH of the solution. The surface free energy values were in the range of 20-30 dynes/cm, which was appropriate for a favorable interaction with blood. From the Young's module curve, it could be seen that elastic hydrogels were obtained with increment of ChL in the PVA/ChL blends. Values of platelet adhesion and whole blood clotting times for the PVA/ChL blends as well as the increase of ChL, which appears to reduce the fibrinogen adsorption on the PVA/ChL membranes, demonstrated that the blood compatibility of PVP/ChL blends is superior to that separated polymers. The results of in vivo experiments in rats were in very good agreement with these observations, suggesting that PVA/ChL may serve as a new type of potential wound-dressing material.  相似文献   
102.
This study details our experience with a new laparoscopic technique called “Slim-Mesh” without using transabdominal full-thickness stitches, to treat ventral and incisional hernias (V/IH). Since 2009–May 2015, 28 consecutive patients with V/IH were treated in our center, with this new SM technique. Fifty percent males were included in this retrospective study, averaging 59 years (range 31–81 years). Mean body mass index was 26 and VH size was <10 cm in 24 cases and in 4 cases was larger, up to 22 cm. Mean operative time in the 28 V/IH patients was 97 min (range 57–160 min) and in those with V/IH larger than 10 cm it was 135 min. In 14.2% of patients laparoscopy diagnosed others V/IH previously undetected by physical examination and CT-scan. In all patients a composite mesh was used, up to 30 cm in size. In this series we had one intraoperative complication (3.6%) with transient bradycardia, but no conversion occurred; no early postoperative complication was detected. Mean length of hospital stay was 3.0 days. Mean follow-up time was 40 months (range 13–78 months). Late surgical complications included one case (3.6%) of incisional hernia recurrence and one case of 10 mm trocar site incisional hernia. This new surgical technique for V/IH repair, makes easy the handling and fixation of the composite mesh without using transabdominal fixation sutures, and appears in our experience fast, and simple.  相似文献   
103.
The diagnosis of nodular sclerosing classical Hodgkin lymphoma (NSCHL) by fine‐needle aspiration (FNA) biopsy has historically been a diagnostic challenge due to the usual paucicellularity of the specimen. This case report, and other previously published reports, suggests that there is another facet to the potentially challenging diagnosis of this particular variant of Hodgkin lymphoma (HL): the presence of suppurative‐necrotizing changes mimicking an infectious etiology. The patient presented here underwent FNA biopsy of an acutely enlarged supraclavicular lymph node and cytologic smears showed marked acute inflammation in a background of necrosis. A diagnosis of infectious suppurative lymphadenitis was made at that time. After a negative infectious work‐up with infectious disease consultation, an excisional biopsy was performed and the patient was definitively diagnosed with NSCHL. The presence of neoplastic Hodgkin and Reed‐Sternberg cells in the purulent exudate was minimal and only appropriately identified after retrospective review. This particular subtype of classical HL represents a potential pitfall in FNA biopsy cytology. Consequently, the cytopathologist and surgeon should always consider this entity in the differential diagnosis of a suppurative, lymphadenitis‐like aspirate, and pursue repeat FNA or an excisional biopsy if there is any clinical index of suspicion. Diagn. Cytopathol. 2014;42:238–241. © 2011 Wiley Periodicals, Inc.  相似文献   
104.
Mina M  Braut A 《Cells, tissues, organs》2004,176(1-3):120-133
In recent years there has been increasing progress in identifying stem cells from adult tissues and their potential application in tissue engineering. These advances provide a promising future for tooth replacement/regeneration. Essential for this approach is the identification of donor stem cells for various components of the teeth. Our studies show that pOBCol3.6GFPtpz and pOBCol2.3GFPemd transgenic animals provide a unique model to gain insight into stem cells in the dental pulp. Our in vivo studies of the developing teeth of these transgenic lines show both Col1a1-GFP transgenes are expressed in functional and fully differentiated odontoblasts. The patterns of expression of Col1a1-GFP transgenes during odontoblast differentiation correlates with the expression of DSPP. In the developing craniofacial bones both Col1a1-GFP transgenes are also expressed in osteoblasts and osteocytes of alveolar and calvarial bones. In the alveolar bones, the expression of Col1a1-GFP in osteocytes correlates with the expression of DMP1. Col1a1-3.6-GFP is expressed in the entire layer of the periosteum and in suture mesenchyme containing osteoprogenitor cells. On the other hand, Col1a1-2.3- GFP expression was limited to the osteoblastic layer of the periosteum and was not detected in the fibroblastic layer of the periosteum or in the suture mesenchyme. These observations indicate that Col1a1-3.6-GFP and Col1a1-2.3-GFP transgenes identify different subpopulations of cells during intramembranous ossification. By using the coronal portion of dental pulps isolated from postnatal transgenic mice our observations also provide direct evidence that the dental pulp contains progenitor/stem cells capable of giving rise to a new generation of odontoblast-like cells, as well as osteoblast-like cells.  相似文献   
105.
Searching for a mechanism underlying autoimmunity in autism, we postulated that gliadin peptides, heat shock protein 60 (HSP-60), and streptokinase (SK) bind to different peptidases resulting in autoantibody production against these components. We assessed this hypothesis in patients with autism and in those with mixed connective tissue diseases. Associated with antigliadin and anti-HSP antibodies, children with autism and patients with autoimmune disease developed anti-dipeptidylpeptidase I (DPP I), anti-dipeptidylpeptidase IV (DPP IV [or CD26]) and anti-aminopeptidase N (CD13) autoantibodies. A significant percentage of autoimmune and autistic sera were associated with elevated immunoglobulin G (IgG), IgM, or IgA antibodies against three peptidases, gliadin, and HSP-60. These antibodies are specific, since immune absorption demonstrated that only specific antigens (e.g., DPP IV absorption of anti-DPP IV), significantly reduced IgG, IgM, and IgA antibody levels. For direct demonstration of SK, HSP-60, and gliadin peptide binding to DPP IV, microtiter wells coated with DPP IV were reacted with SK, HSP-60, and gliadin. They were then reacted with anti-DPP IV or anti-SK, anti-HSP, and antigliadin antibodies. Adding SK, HSP-60, and gliadin peptides to DPP IV resulted in 27 to 43% inhibition of the DPP IV-anti-DPP IV reaction, but DPP IV-positive peptides caused 18 to 20% enhancement of antigen-antibody reactions. We propose that (i) superantigens (e.g., SK and HSP-60) and dietary proteins (e.g., gliadin peptides) in individuals with predisposing HLA molecules bind to aminopeptidases and (ii) they induce autoantibodies to peptides and tissue antigens. Dysfunctional membrane peptidases and autoantibody production may result in neuroimmune dysregulation and autoimmunity.  相似文献   
106.
107.
Clinical Rheumatology - The nail unit is a subject of interest in several diseases, often involving different medical fields. Even if few data are available for psoriasis and psoriatic arthritis,...  相似文献   
108.
109.
OBJECTIVE: To investigate the association of asymmetry in leg extension power (LEP) with walking and standing balance. DESIGN: Cross-sectional analysis. SETTING: Research laboratory. PARTICIPANTS: Healthy female twins (N=419), ages 63 to 75 years. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: The LEP difference between the stronger and the weaker leg, measured with the Nottingham power rig, was calculated. Ten-meter maximal walking velocity was assessed in a laboratory corridor on a wide (170 cm) and narrow (35 cm) track, and the ability to maintain tandem stance for 20 seconds was recorded. RESULTS: The mean LEP difference +/- standard deviation between the legs was 15%+/-9% (P<.001). Those with large LEP difference had lower walking velocity and poorer standing balance than those with small LEP difference, in particular when the LEP of the stronger leg was below the median. CONCLUSIONS: Even in healthy older women, substantial LEP asymmetry between the lower limbs was present, encumbering walking and standing balance. Lower-limb muscle power asymmetry warrants further study in order to develop well-targeted strategies for preventing mobility limitation in older people.  相似文献   
110.
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