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41.
Zaffe D Rodriguez Y Baena R Rizzo S Brusotti C Soncini M Pietrabissa R Cavani F Quaglini V 《Journal of biomedical materials research. Part A》2003,64(2):365-371
Fourteen titanium dental implants (Tioblast) were implanted singly in the proximal tibia of New Zealand rabbits for 120 days. A bone defect was surgically produced and filled with Bio-Oss around six of these implants. After the animals were sacrificed and their organs harvested, bone segments were fixed and methacrylate embedded after the push-in test had been performed. Microradiography was performed on longitudinal sections of the implants, whereas scanning electron microscope analysis was performed on the remaining embedded half-implants using secondary electrons only. The results showed that the implants were apically and coronally surrounded by bone, whether Bio-Oss was used or not. Fractures were evident through the newly formed bone and between the pre-existing and newly formed bone. Some fracture lines propagated through the bone and stopped at the implant surface without continuing along the bone-titanium interface. Detachment between the implant and the bone occurred at the coronal extremity of the implants and along its cervical region. These results highlight the fact that the bone-titanium interface has a high resistance to loading. It exhibited greater resistance than the newly formed bone and seems to behave in a manner similar to the cement lines of osteons. 相似文献
42.
Macchi V Tiengo C Porzionato A Stecco C Parenti A Mazzoleni F Ger R De Caro R 《Clinical anatomy (New York, N.Y.)》2005,18(8):580-588
The abductor hallucis muscle flap is commonly used as a proximally-based flap in the management of ankle, heel, and midfoot lesions, where it is ideally suited for closing defects. This study investigates the anatomical details of this muscle in 13 fresh male cadavers. The medial plantar artery (MPA) was studied by dissection and macroscopic analyses to document the relationship of its superficial and deep branches with respect to the abductor hallucis muscle (AHM). Three main patterns could be described. In Pattern A (54%) the MPA divides into two branches. The deep branch reaches the deep surface of the AHM, supplying its proximal part, and the superficial branch courses between the AHM and the flexor digitorum brevis, to end as the first plantar metatarsal artery. The latter supplies two to three small branches to the distal part of the AHM. The fibers of the AHM end symmetrically on the two sides of the tendon and the muscle presents an arciform shape. The MPA, in Pattern B (38%), lacks a deep branch and continues along the lateral border of the AHM as a superficial branch that supplies proximal and distal collaterals to the muscle. The muscle fibers of the AHM end mainly on the medial side of the tendon. The muscle belly presents an arciform shape and is located on the medial margin of the foot superomedially with respect to Pattern A. In Pattern C (8%) the MPA continues as a large deep branch on the deep surface of the AHM and ends as the medial collateral artery of the big toe. A smaller superficial branch of the MPA provides a few collaterals to the AHM from its proximal part and to the flexor digitorum brevis in its distal part. The AHM fibers end mainly on the lateral side of the tendon and morphologically the muscle presents a straight line on the sole of the foot compared to Pattern A. Although Patterns B and C, from a surgical point of view, necessitate interruption of the main trunk of the MPA, Pattern A may permit the vascularization of the muscles of the medial side of the sole of the foot by the superficial trunk of the MPA. Because preoperative radiological study of the plantar vessels correlate with the morphological characteristics of the AHM observed during surgery, such imaging may be useful in determining the appropriate flap design based on the patient's unique pattern of MPA branching. 相似文献
43.
Renata Boldrini Roberto Biselli Cesare Bosman 《Pathology, research and practice》2001,197(11):753-757
Three children with malabsorption presumably caused by celiac disease had undergone jejunal biopsy. While a histological examination revealed microvacuolization of enterocytes in the absence of celiac lesions, an ultrastructural investigation disclosed numerous chylomicrons and larger lipid vacuoles inside the cytoplasm of enterocytes, mostly in the supranuclear region. No chylomicrons were evident in the interstitium between adjacent enterocytes, as observed in normal subjects. These ultrastructural findings allowed for the diagnosis of "Chylomicron retention disease" (CRD). CRD was described for the first time by Anderson in 1961, and it is included in the group of disorders of biosynthesis and secretion of B apolipoproteins (apoB). This disease, in particular, appears to result from a specific defect involving the secretion of lipoproteins containing apoB-48 from the gut, with the complete absence of post prandial chylomicrons in the sera. CRD needs to be recognized early because of its adverse effects on growth and its potential for neurological and ocular complications, and the ultrastructural identification of chylomicron-size lipid droplets clustered in the enterocytes, with the absence of fat outside the cells, represents the gold standard to identify CRD. together with clinical aspects and laboratory measurements. In this study, we describe the histological and ultrastructural aspects observed in three pediatric cases of CRD. 相似文献
44.
Malignancy-associated allelic losses on the X-chromosome in foregut but not in midgut endocrine tumours 总被引:2,自引:0,他引:2
Pizzi S D'Adda T Azzoni C Rindi G Grigolato P Pasquali C Corleto VD Delle Fave G Bordi C 《The Journal of pathology》2002,196(4):401-407
Information on genetic changes involved in the progression of gastroenteropancreatic (GEP) endocrine tumours is scanty. On the other hand, the identification of molecular markers of malignancy could be crucial for the prognostic evaluation of these neoplasms, which is hardly predictable on the basis of conventional histological criteria. An association of X-chromosome deletions with malignancy has already been found in gastric endocrine tumours. To investigate this further, a comparative loss of heterozygosity (LOH) analysis was performed on 17 pancreatic endocrine tumours (PETs) and 17 intestinal (ten ileal, six appendiceal, and one rectal) carcinoids from female patients. The relationship of X-chromosome LOH with the ploidy status of the neoplasms was also investigated. LOH was found in six of eight malignant PETs (60% of the informative markers), but was infrequent in the nine benign ones (4.5%). In contrast, although retention of heterozygosity was consistently observed in benign midgut tumours, LOH was infrequent in malignant carcinoids (15%). No correlation was found between LOH and the ploidy status. These results indicate an association between X-chromosome LOH and malignancy in foregut endocrine tumours. The lack of such an association in midgut carcinoids suggests that different molecular mechanisms are involved in the progression of these two categories of endocrine neoplasms, which are otherwise considered to be closely related. These findings emphasize the need for further molecular studies on GEP endocrine tumours, carefully subdivided according to their anatomical site of origin. 相似文献
45.
Del Fante C Perotti C Viarengo G Bergamaschi P Tinelli C Bellotti L Marchesi A Parisi C Salvaneschi L 《Stem cells and development》2005,14(6):734-739
Immunomagnetic CD34+ cell selection (ICS) is a widely employed technology in autotransplant and allotransplant settings. When an haploidentical transplant is performed, a high dose of purified CD34+ cells together with efficient T and B cell depletion are required to minimize the risks of graft versus host disease (GVHD) and Epstein-Barr virus (EBV)-related lymphoma. To ameliorate the performances of the CliniMACS (Miltenyi Biotec) ICS device, we compared 73 ICS performed following the manufacturer's recommended platelet depletion versus 48 performed after adjunctive centrifugations to increase platelet depletion of the leukapheresis (LKF) product. A total of 121 ICS (from single or fractioned LKF products) were carried out on 93 LKF collected from 47 related healthy donors. A statistical significance in terms of CD34+ cell recovery (81.8% vs. 71.2%) was found in favor of the modified ICS procedure (p=0.0049) with a comparable stem cell purity and viability. The modification of the standard manufacturer's technique for increasing platelet depletion can further improve the recovery of stem cells with no influence on T and B cell depletion. These results demonstrate the negative influence exerted on CD34+ cell recovery by LKF platelet contamination. 相似文献
46.
Andrea P. Rossi Cesare Caliari Silvia Urbani Francesco Fantin Piero Brandimarte Angela Martini Elena Zoico Giulia Zoso Alessio Babbanini Alfredo Zanotelli Mauro Zamboni 《Nutrients》2021,13(2)
Background: SARC-F and Mini Sarcopenia Risk Assessment (MSRA) questionnaires have been proposed as screening tools to identify patients at risk of sarcopenia. The aim of this study is to test the use of SARC-F and MSRA, alone and combined, as a pre-screening tool for sarcopenia in geriatric inpatients. Methods: 152 subjects, 94 men and 58 women, aged 70 to 94, underwent muscle mass evaluation by dual energy X-ray absorptiometry (DXA), muscle strength evaluation by handgrip, and completed the MSRA, SARC-F and Activity of daily living (ADL) questionnaires. Results: 66 subjects (43.4%) were classified as sarcopenic according to the European Working Group on Sarcopenia in Older People 2 (EWGSOP2) criteria. The 7-item SARC-F and MRSA and 5-item MSRA showed an area under the curve (AUC) of 0.666 (95% confidence interval (CI): 0.542–0.789), 0.730 (95% CI: 0.617–0.842) and 0.710 (95% CI: 0.593–0.827), respectively. The optimal cut-off points for sarcopenia detection were determined for each questionnaire using the Youden index method. The newly calculated cut-off points were ≤25 and ≤40 for MSRA 7- and 5-items, respectively. The ideal cut-off for the SARC-F was a score ≥3. Applying this new cut-off in our study population, sensitivity and specificity of the 7-item MSRA were 0.757 and 0.651, and 0.688 and 0.679 for the 5-item MSRA, respectively. Sensitivity and specificity of SARC-F were 0.524 and 0.765, respectively. The combined use of the 7-item SARC-F and MSRA improved the accuracy in sarcopenia diagnosis, with a specificity and sensitivity of 1.00 and 0.636. Conclusion: 7-item SARC-F and MSRA may be co-administered in hospital wards as an easy, feasible, first-line tool to identify sarcopenic subjects. 相似文献
47.
Background:The measurement of cross-sectional area (CSA) is a diagnostic tool to detect entrapments syndrome. The aim of this study was to compare the clinical outcome in elbows undergoing endoscopic and “in situ” open cubital tunnel release for cubital tunnel syndrome (CuTS) using ultrasound-related changes in the largest CSA of the ulnar nerve. The purpose is to determine the association between clinical outcome and CSA. Methods: From May 2011 to April 2016, 60 patients with CuTS were prospectively followed and not randomly divided in two groups: 30 patients undergoing an endoscopic release (ER) and 30 patients with “in situ” open neurolysis (OR). A sonographic examination was performed by the senior authors at baseline and 3, 6, and 12 months after surgical decompression. Results: CSA values were statistically significantly lower in the ER. Hand grip strength difference with Jamar test was not statistically significant a 12 months (39 kg vs 27 kg). Static-2 point discrimination test difference was only statistically significant lower in the endoscopic group at 3, 6 and 12 months but not clinically relevant (5 mm vs 6 mm). The American Shoulder and Elbow Surgeons—Elbow questionnaire (ASES-e) function score, ASES-e Pain score, and ASES-e Satisfaction score were not statistically significant different between the two groups at 3, 6, and 12 months post operatively. Conclusions: The study confirms that in spite of lower values of CSA in the ER, there is not a statistically significant difference between the two techniques in terms of subjective outcomes. Ultrasound (US) measurements seem to have a limited value in clinical results of patients treated for entrapment neuropathy of the ulnar nerve.Type of study/LOE: Prognostic Level III 相似文献
48.
T. Cochrane A. W. Nathan R. S. Bexton C. Callicott R. A. J. Spurrell A. J. Camm 《Medical & biological engineering & computing》1984,22(1):19-23
A microcomputer-based pacemaker system for the evaluation of pacemaker treatment of tachycardia is described. The system may
be used to study tachycardia initiation, tachycardia termination or a combination of the two. The software incorporates a
visual display unit screen handling package which provides the user-system interface. System-patient interfacing is performed
by a separate pacing and sensing unit which communicates with the computer via standard digital input/output lines. Several
pacing options are available, selectable from a screen-displayed menu. Each selection also has an associated set of programmable
parameters which may be adjusted, within allowed limits, to suit particular studies. Examples of the use of the system for
tachycardia termination are given. The main programming language for the controlling software was Fortran IV. Some routines
were necessarily written in assembly language. The system is useful for evaluation purposes and forms the basis of a cardiac
pacemaker development tool. 相似文献
49.
Marco Berlucchi Cesare Piazza Laura Blanzuoli Giuseppe Battaglia P. Nicolai 《European archives of oto-rhino-laryngology》2000,257(7):402-405
Schwannomas are neurogenic neoplasms rarely found in the sinonasal tract, where localization to the nasal septum is exceedingly
rare (only 11 cases have been described in the western literature). We report the case of a 29-year-old white male with a
schwannoma completely filling the left nasal fossa and arising from the bony part of the septum. A computer tomography (CT)
scan and a biopsy suggestive of benign schwannoma were obtained before the lesion was removed by a degloving approach. The
preoperative diagnosis of nasal septum schwannoma was confirmed. The patient is asymptomatic and without endoscopic evidence
of recurrence 7 years after surgery. A review of the literature with particular emphasis on the clinical presentation, histological
features, differential diagnosis and therapeutic options for such a rare lesion is included.
Received: 11 June 1999 / Accepted: 10 February 2000 相似文献
50.
Dominici Carlo Nicotra Maria Rita Alemaà Stefano Bosman Cesare Castello Manuel A. Donfrancesco Alberto Gallo Pietro Natali Pier Giorgio 《Journal of neuro-oncology》1997,31(1-2):57-64
In neuroblastoma, high levels of mRNA for p14h
trkA
and p75
LNGFR
neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140
trkA
and ME20.4 anti-p75
LNGFR
mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140
trkA
and in 5 of 28 tumors for p75
LNGFR
. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140
trkA
(p < 0.05) and 71% (20 of 28 cases) for p75
LNGFR
(p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio. 相似文献