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991.
It is rare for traumatic amputation of the big toe to occur as a single injury. This trauma is especially significant in children for influencing foot development and for possible psychological impact. Two cases of successful replantation of completely amputated big toes in two girls, 2 years 7 months and 5 years 2 months old, are presented. Follow-up was 10 years. In the younger child, the replanted big toe was 49.2 percent shorter compared to the contralateral side, because growth was limited by the affected growth zone in the proximal phalanx. In the older child, the growth zone of the bone was intact, with consequent bone growth unimpaired, and an initial shortage of 10.4 percent was reduced to 2 percent compared to the contralateral side.  相似文献   
992.
Dotan ZA  Tal R  Golijanin D  Snyder ME  Antonescu C  Brennan MF  Russo P 《The Journal of urology》2006,176(5):2033-8; discussion 2038-9
PURPOSE: Urological sarcomas are rare. We describe a continued single institutional experience during 25 years. MATERIALS AND METHODS: The records from July 1977 to July 2003 were reviewed of all patients at our institution with sarcoma arising in the urinary tract or male genital system who were 16 years or older at diagnosis. RESULTS: The primary tumor site in 131 patients was the bladder in 20, the kidney in 26, paratesticular in 57, the prostate in 21 and other in 7. Median followup was 4.0 years. The most common histological subtypes were leiomyosarcoma in 29% of cases and liposarcoma in 26%. Median tumor size was 7 cm and 78% of lesions were high grade. Of the patients 28 (21%) presented with metastatic disease and their median survival was 1.4 years compared to 10.7 years in patients without metastatic disease (p < 0.0001). Disease specific survival was 56% and 42% at 5 and 10 years, respectively and median survival was 7.6 years. On univariate analysis unfavorable prognostic variables for disease specific survival were metastasis at presentation, high tumor grade, a lack of leiomyosarcoma and liposarcoma histological subtypes, prostate sarcoma and large tumor size, incomplete surgical resection and positive surgical margin. Patient sex, age and surgical margin status were not significant predictors. On multivariate analysis 2 variables remained significant predictors of disease specific survival, including tumor size (HR 1.1, 95% CI 1.02 to 1.17) and absent metastasis at diagnosis (HR 4.9, 95% CI 1.4 to 17.2). CONCLUSIONS: Predictors of disease specific survival include local disease at presentation, complete tumor resection and tumor grade, size, location and histological subtype. With adequate surgical treatment most patients who presented with primary disease and underwent complete surgical resection achieved prolonged disease specific survival.  相似文献   
993.
Ultrasonography allows providers to noninvasively image an area of interest in real time without the risks of ionizing radiation or nephrotoxic contrast agents. This article present basic concepts of ultrasound along with new advances in ultrasound technology and their applications in small parts evaluation.  相似文献   
994.
Huang G  Dragan M  Freeman D  Wilson JX 《Glia》2005,51(1):47-55
Elevation of the total homocysteine (tHcy) concentration in plasma has been implicated in neurodegeneration in patients with stroke, dementia, Alzheimer disease, and Parkinson disease. Because the mechanisms controlling brain tHcy are unknown, the present study investigated its synthesis and transport in primary rat brain cell cultures. We found that the catechol-O-methyltransferase (COMT) substrate 3,4-dihydroxybenzoic acid (DHB) increased export of tHcy in astrocytes, but not in neurons. The export mechanism was selective for tHcy over cyst(e)ine, total glutathione (tGSH) or cysteinylglycine (Cys-Gly). tHcy export from astrocytes was also induced by the COMT substrates levodopa (L-DOPA), dopamine and quercetin, and it was blocked by the COMT inhibitors tropolone and entacapone. This export was associated with increased synthesis of tHcy because both intracellular and extracellular tHcy concentrations rose during COMT activation. Incubation in cyst(e)ine-deficient medium inhibited the tHcy export response to COMT activation. Exogenous tHcy (100 muM) was accumulated into neurons, but not into astrocytes. We conclude that activation of COMT causes sustained synthesis of Hcy in astrocytes and transport of this amino acid to neurons.  相似文献   
995.
Extended release dipyridamole (DIP) is widely used in clinical practice as an Aggrenox formulation, which is proven to improve outcomes for secondary stroke prevention in patients after acute vascular events. However, presently established fluorometry techniques are not suitable for trace amount determinations, because of the variable background fluorescence. The authors sought to determine whether biological fluid pH is important for the serial measures of DIP levels in the animal experiments and in patients treated with Aggrenox after ischemic stroke. Post-stroke patient (n = 34) and mice (n = 25) samples were tested to determine DIP levels by established techniques with FluoroMax 3 spectrofluorometer. Both the absorption and emission spectra of DIP were affected by modifications in pH. Fluorescence of DIP was found to be maximal at a wavelength of 490 nm (excitation 420 nm) and the spectral pattern was independent of pH. The intensity of fluorescence, however, was drastically lower at low pH (at pH 2.6, fluorescence was 4% of intensity at pH 9.8). Background plasma fluorescence, however, was completely unaffected by changes in pH. Using these fluorometric characteristics, a regression model that facilitates the efficient and sensitive determination of DIP concentration in biological fluids was formulated. Exploiting pH-dependent characteristics of DIP versus serum fluorescence patterns permits a convenient mathematical model to determine DIP concentration. This relatively inexpensive and time-efficient procedure can quantify drug levels in human/animal plasma/serum, thereby directly determining the level of patient adherence to the prescribed drug regimen, be it in the context of clinical trials or compliance with the animal protocol.  相似文献   
996.
Yang Y  Yang F  Xiong Z  Yan Y  Wang X  Nishino M  Mirkovic D  Nguyen J  Wang H  Yang XF 《Oncogene》2005,24(30):4778-4788
Bcl-xL plays a critical role in maintaining cell survival. However, the relationship between the potential interaction of Bcl-xL with other cytosolic proteins and the regulation of cell survival remains incompletely defined. We have identified translationally controlled tumor protein (TCTP), a multifunctional protein, as a novel antiapoptotic Bcl-xL-interacting protein. TCTP interacted in vivo and in vitro with Bcl-xL, and their sites have been mapped to an N-terminal region of TCTP and the Bcl-2 homology domain 3 of Bcl-xL. Consistent with a role in maintaining T-cell survival during activation, TCTP was significantly upregulated in murine T cells activated by T-cell antigen receptor (TCR) ligation and CD28 costimulation, which was correlated with the upregulation of Bcl-xL in activated T cells. Moreover, downregulation of TCTP expression by antisense technology in T cells results in the increase of T-cell apoptosis. Furthermore, the N-terminal region of TCTP was required for its ability to inhibit apoptosis. In conclusion, this study has demonstrated that an N-terminal region of a cytosolic protein, TCTP, is required for its binding to Bcl-xL and for its antiapoptotic activity.  相似文献   
997.
BACKGROUND: Hepatitis C virus (HCV) infection is the most frequent cause of chronic hepatitis, cirrhosis, and hepatocellular carcinoma in the world. Acute hepatitis C is the most commonly asymptomatic liver disease with the development of chronic HCV infection in the majority of infected patients. Studies of the natural history of HCV infection suggest that only 15-30% of patients with acute infection recover spontaneously. Others, up to 85% of the infected patients develop chronic hepatitis C. Acute hepatitis C is so uncommon and with the unpredictable occurrence, and of the low frequency, that it is difficult to determine the optimal treatment of this disease. There have been many randomized, controlled trials of the therapy in patients with chronic hepatitis C, but none of an adequate size or rigor in patients with acute hepatitis C. Therefore, the causal treatment of patients with acute hepatitis C aimed at the prevention of chronic liver disease is necessary. CASE REPORT: We have treated a patient with anicteric form of acute hepatitis C after a three-month outpatient follow-up using a combined therapy: pegylated interferon-alpha 2a, 180 microg, subcutaneously, once a week plus ribavirin 1000 mg orally once a day. The treatment lasted 24 weeks. Stable biochemical and virological response was achieved both at the end of the treatment and 6 months after the completion of the therapy. CONCLUSION: We believe that the above mentioned might be one of the approaches to the treatment of acute hepatitis C. However, further prospective studies with significantly larger number of patients are necessary for the definite conclusions about the treatment of HCV infections.  相似文献   
998.
BACKGROUND: Pancreatic fistulas are not frequent after the needle biopsy of the pancreatic head. The aim was to present a patient with this type of fistula who was managed using the surgical method never previously applied in our surgical practice. CASE REPORT: In our patient, pancreatic fistula appeared at the site of the needle biopsies due to the development of the necrosis. Since the conservative treatment with octreotide and the total parenteral nutrition were without result, we turned to the surgical treatment by placing a silicone prosthesis along the pancreatic duct into the duodenum, next through the Roux-en-Y flexure to provide the external drainage of a pancreatic juice. Postoperatively, applying the conservative treatment, pancreatic fistula disappeared, and a silicone prosthesis was removed three weeks later. CONCLUSION: The described surgical procedure can be successful i managing fistulas which occur after the pancreatic necrosis.  相似文献   
999.
This paper analyzes the reliability of the Iscan's sternal rib-ends phase method for the assessment of individual age at the time of death in the Balkan population. The method is based on the morphological age changes of the sternal rib ends. The tested samples consisted of 65 ribs from autopsy cases in the Institute for Forensic Medicine, University of Belgrade, during 1999-2002 (23 females, and 42 males of various ages, ranged from 17-91 years), according to the forensic documents. Significant differences between the real chronological age of the individuals and the values established by the Iscan's method was found, especially in the older categories (phases 6 and 7), in both males and females. The results of the discriminative analysis showed the values of the highest diagnostic relevance for the assessment of age in our population: the change of the depth of the articular fossa, the thickness of its walls, and the quality of the bones.  相似文献   
1000.
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