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31.
An inflammatory myofibroblastic tumor is an uncommon benign tumor located in various organs that can be misdiagnosed as a malignant neoplasm. We herein present two patients with ileocecal inflammatory myofibroblastic tumors. An abdominal mass was detected in a 13-year-old girl and a 15-year-old boy who presented with paleness, fatigue, intermittent fever, and night sweating. The radiological findings confirmed a mass originating from the ileocecal region. The presumptive diagnosis was Burkitt’s lymphoma. The histopathological diagnosis was inflammatory myofibroblastic tumor. After a surgical resection, all systemic symptoms rapidly resolved. Inflammatory myofibroblastic tumor is a rare pseudosarcomatous clinical and pathological entity. Although this tumor is more commonly reported in the lung, it can be detected in extrapulmonary sites, including the mesentery. Because the choice of treatment for this tumor is conservative surgery, an accurate preoperative analysis is important to avoid any unnecessary aggressive surgical intervention or other therapeutic approaches.  相似文献   
32.
Fetal skin wounds heal without inflammation, collagen deposition or wound contraction. The mechanism of this process is unknown, but may be unique to fetal cells, the fetal environment, or an combination of both. In order to determine whether fetal cells are the only factor responsible for scarless wound healing, an experimental study was performed on ten cats who were in the last trimester of their pregnancy. Skin grafts were transferred from mother to fetus and fetus to mother. The fetal skin grafted to the mother was biopsied between the eighth and tenth postoperative days and was evaluated histopathologically on days 18–20. Biopsy revealed scar formation in both the fetal grafts in the adult and maternal grafts in the fetus. We can conclude that scarless wound healing in the fetus is not solely due to fetal cells.  相似文献   
33.
Background. Haemoglobin-based oxygen carriers (HBOCs) are assessedas blood substitutes in patients with perioperative anaemiaincluding patients at risk for perioperative cardiac ischaemia.There is controversy as to whether HBOCs are beneficial or deleteriousduring ischaemia–reperfusion (I–R). Therefore theeffects of HBOC-200 on I–R injury were evaluated in arandomized placebo-controlled animal trial. Methods. Animals were randomized to receive either placebo i.v.without I–R (sham group, n=9), placebo i.v. with I–R(control group, n=10), HBOC-200 0.4 g kg–1 i.v. priorto I–R (prophylaxis group, n=12) or HBOC-200 0.4 g kg–1i.v. during I–R (therapy group, n=15). I–R consistedof 25 min of acute ligature of the left coronary artery followedby 120 min of reperfusion. Measurements included assessmentof the area at risk and infarct size using triphenyl tetrazoliumchloride (TTC) stain, DNA single-strand breaks (in situ nicktranslation with autoradiography/densitometry) and cardiac arrhythmias. Results. Infarct size within the area at risk was 62 (SD 15)%(control), 46 (10)% (prophylaxis, P<0.025 vs control) and61 (9)% (therapy, P<0.85 vs control). The frequency of DNAsingle-strand breaks was reduced vs control in the sham (P<0.01)and prophylaxis (P<0.04) groups and was almost the same inthe therapy group (P<0.75). The severity of cardiac arrhythmiasduring ischaemia was lower compared with control in the sham(P<0.001) and prophylaxis (P<0.039) groups, but therewas no difference in the therapy group. Conclusion. This study demonstrates that neither prophylacticnor therapeutic application of the cell-free haemoglobin solutionHBOC-200 aggravates cardiac I–R injury. Furthermore, theprophylactic approach may offer a new opportunity for pretreatmentof patients at risk for perioperative ischaemic cardiac events. The results were presented in part at the Congress of the EuropeanSociety of Anaesthesia, Glasgow, UK, June 2003 (‘BestAbstract Award’), and at the Annual Meeting of the AmericanSociety of Anesthesiologists, San Francisco, CA, USA, October2003. Declaration of interest. T. G. Standl has received lecture honorariaand travel fees from Biopure Corporation, Boston, MA, the manufacturerof HBOC. The Department of Anaesthesiology, University Hospital,Hamburg-Eppendorf, received restricted grants from Biopure Corporation,Boston, MA, between 1994 and 1998 for animal and clinical phaseII and III trials. M.A. Burmeister is Vice President Researchand Development, Hospital Care Division, B. Braun MelsungenAG, Melsungen, Germany. B. Braun, a global health care supplier,cooperated with Biopure Corporation, Boston, MA, on HBOC developmentuntil 1996. The work presented in this paper was done independentlyof and without any support from B. Braun.  相似文献   
34.
Abstract

Purpose: The aim of the present study was to evaluate the effect of acetyl-l-carnitine (ALC) and N-acetyl cysteine (NAC) on ionizing radiation (IR)-induced cytotoxicity and change in DNA damage-related genes in House Ear Institute-Organ of Corti 1 (HEI-OC1) cells.

Methods: HEI-OC1 cells were irradiated with 5?Gy radiation and treated by eight combinations of NAC and/or ALC: control, NAC, ALC, IR, NAC?+?IR, ALC?+?NAC, ALC?+?IR, and ALC?+?NAC?+?IR. Cell viability, apoptotic cell death, and DNA damage were measured at the 72nd hour. Eighty-four IR-induced DNA-damage-related genes were determined by RT-PCR gene array and >10-fold changes were considered significant.

Results: IR decreased cell viability by about 50% at 72?hours of incubation. In particular, the ALC and/or NAC combination before IR protected the HEI-OC1 cells (p?<?.05). Single and combination treatment prior to IR led to lower apoptotic cell death (p?<?.05). There was a significant lower DNA damage in ALC?+?NAC?+?IR group compared to IR group (p?<?.05). Expressions of Brca2, Xpc, Mlh3, Rad51, Xrcc2, Hus1, Rad9a, Cdkn1a, Gadd45a which are the DNA-repair genes were found to be significantly higher in NAC?+?ALC?+?IR group than those in individual treatment of ALC or NAC.

Conclusions: ALC and/or NAC treatment prior to IR led to higher cell viability and lower apoptotic cell damage compared to the IR group. The results of the study show that the ALC?+?NAC combination treatment inhibits DNA damage and induces DNA-repair genes to repair radiation damage, and this combination treatment is more effective against radiation-induced DNA damage than NAC or ALC therapy individually.  相似文献   
35.
Most experiments assume a global transit delay time with blood flowing from the tagging region to the imaging slice in plug flow without any dispersion of the magnetization. However, because of cardiac pulsation, nonuniform cross‐sectional flow profile, and complex vessel networks, the transit delay time is not a single value but follows a distribution. In this study, we explored the regional effects of magnetization dispersion on quantitative perfusion imaging for varying transit times within a very large interval from the direct comparison of pulsed, pseudo‐continuous, and dual‐coil continuous arterial spin labeling encoding schemes. Longer distances between tagging and imaging region typically used for continuous tagging schemes enhance the regional bias on the quantitative cerebral blood flow measurement causing an underestimation up to 37% when plug flow is assumed as in the standard model. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
36.
Background and aims Occurrence of tumor relapse is frequent in patients with pancreatic cancer despite the absence of residual tumor detectable at primary surgery and in histopathological examination. Therefore, it has to be assumed that current tumor staging procedures fail to identify minimal amounts of disseminated tumor cells, which might be precursors of subsequent metastatic relapse. The aim of this study was to assess the prognostic impact of minimal tumor cell spread detected in lymph nodes classified as “tumor-free” in routine histopathologic evaluation. Materials and methods A total of 154 “tumor-free” lymph nodes from 59 patients with pancreatic cancer who underwent intentionally curative tumor resection were examined by immunohistochemistry for disseminated tumor cells. Results Fifty (32.5%) of the “tumor-free” lymph nodes obtained from 36 (61%) patients displayed disseminated tumor cells. Multivariate survival analysis revealed that the presence of disseminated tumor cells in “tumor-free” lymph nodes is an independent prognostic factor for both a significantly reduced relapse-free survival (p = 0.03) and overall survival (p = 0.02). Conclusions The frequent occurrence and prognostic impact of immunohistochemically identifiable disseminated tumor cells in lymph nodes of patients with operable pancreatic cancer supports the need for a refined staging system of excised lymph nodes, which should include immunohistochemical examination.  相似文献   
37.
Aim: To evaluate the outcome of repetitive micro-surgical testicular sperm extraction (mTESE) attempts in non-obstructive azoospermia (NOA) cases, in relation to patients' initial testicular histology results. Methods: A total of 68 patients with NOA in whom mTESE had been performed in previous intracytoplasmic sperm injection (ICSI) attempts were reviewed. Results: Among the 68 patients with NOA, the first mTESE yielded mature sperm for ICSI in 44 (64%) (Sp^+), and failed in the remaining 24 (36%) (Sp^-). Following their first trial, 24 patients decided to undergo a second mTESE. Of these 24 patients, no spermatozoa were obtained in 5 patients, and Sp^+ but no fertilization/pregnancy were achieved in 19. In these 24 cases, mTESE was successively repeated for two (n = 24), three (n = 4) and four (n = 1) times. The second attempt yielded mature sperm in 3/5 patients from the Sp group and 16/19 patients from the Sp^+ group. At the third and fourth trials, 4/4 and 1/1 of the original Sp^+ patients were Sp^+ again, respectively. Distribution of main testicular histology included Sertoli cell-only syndrome (16%), maturation arrest (22%), hypospermatogenesis (21%) and focal spermatogenesis (41%). Overall, in repetitive mTESE, 24/29 (82%) of the attempts were finally Sp^+. Conclusion: Repeated mTESE in patients with NOA is a feasible option, yielding considerably high sperm recovery rate. In patients with NOA, mTESE may safely be repeated one or more times to increase sperm retrieval rate, as well as to increase the chance of retrieving fresh spermatozoa to enable ICSI.  相似文献   
38.
Background: Volatile anesthetics are commonly used for general anesthesia. However, these can induce profound cardiovascular alterations. Xenon is a noble gas with potent anesthetic and analgesic properties. However, it is uncertain whether xenon alters myocardial function. The aim of this study was therefore to investigate left ventricular function during anesthesia with xenon compared with isoflurane.

Methods: The authors performed a randomized multicenter trial to compare xenon with isoflurane with respect to cardiovascular stability and adverse effects in patients without cardiac diseases scheduled for elective surgery. Two hundred fifty-nine patients were enrolled in this trial, of which 252 completed the study according to the protocol. Patients were anesthetized with xenon or isoflurane, respectively. Before administration of the study drugs and at four time points, the effects of both anesthetics on left ventricular function were investigated using transesophageal echocardiography.

Results: Global hemodynamic parameters were significantly altered using isoflurane (P < 0.05 vs. baseline), whereas xenon only decreased heart rate (P < 0.05 vs. baseline). In contrast to xenon, left ventricular end-systolic wall stress decreased significantly in the isoflurane group (P < 0.05 vs. baseline). Velocity of circumferential fiber shortening was decreased significantly in the xenon group but showed a more pronounced reduction during isoflurane administration (P < 0.05 vs. baseline). The contractile index (difference between expected and actually measured velocity of circumferential fiber shortening) as an independent parameter for left ventricular function was significantly decreased after isoflurane (P < 0.0001) but unchanged using xenon.  相似文献   

39.
OBJECTIVE: The purpose of this study was to evaluate the effect of immediate and delayed post space preparation on the sealing ability of a new root canal filling material. STUDY DESIGN: Seventy-two extracted teeth were prepared and obturated with gutta-percha/AH-Plus and Resilon/Epiphany sealer by the lateral compaction technique. The teeth were divided randomly into 4 groups, and the post space was prepared either immediately after filling or after the obturated teeth had been stored in saline at 37 degrees C for a week. Leakage was determined by a fluid-transport device. RESULTS: The results showed that immediate post space preparation of the Resilon/Epiphany-filled group had a mean leakage value of 0.81 microL/h, whereas the delayed preparation had a mean leakage value of 0.75 microL/h. No difference (P > .05) in microleakage was found between gutta-percha/AH-Plus and Resilon/Epiphany-filled groups after immediate preparation. There was significant difference between gutta-percha/AH-Plus and Resilon/Epiphany groups in the delayed post space preparation (P < .05). CONCLUSION: Epiphany/Resilon obturation achieved better sealing than gutta-percha/AH-Plus at the apical end, especially in delayed post space preparation when mechanical techniques were used.  相似文献   
40.
The proinflammatory mediator (PIM) levels were assessed in surgically removed samples of herniated cervical intervertebral discs. The objective of this study was to investigate if there is a correlation between the levels of PIMs in disc material and myelopathy associated with cervical intervertebral disc herniation and spondylosis. The role of proinflammatory mediators in the degeneration of intervertebral disc and the inflammatory effects of disc herniations on radicular pain has been previously published. However, the possible relationship between PIMs and myelopathy related to cervical disc herniation and spondylosis has not been investigated before. Thirty-two patients undergoing surgery for cervical disc herniation and spondylosis were investigated. Surgically obtained disc materials, stored at 70 degrees C, were classified into two groups: cervical disc herniation alone or with myelopathy. Biochemical preparation and solid phase enzyme amplified sensitivity immunoassay (ELISIA) analysis of the samples were performed to assess the concentration of mediators in the samples. Very similar values of interleukin-6 were found in both groups whereas the concentrations of mediators were significantly higher in myelopathy group. This study has demonstrated that PIMs are involved in cervical intervertebral disc degeneration with higher concentrations in the samples associated with myelopathy.  相似文献   
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