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101.
PurposeTo report short-term results of empiric transcatheter embolization for patients with advanced malignancy and gastrointestinal (GI) hemorrhage directly from a tumor invading the GI tract wall.Materials and MethodsBetween 2005 and 2011, 37 mesenteric angiograms were obtained in 26 patients with advanced malignancy (20 men, six women; mean age, 56.2 y) with endoscopically confirmed symptomatic GI hemorrhage from a tumor invading the GI tract wall. Angiographic findings and clinical outcomes were retrospectively evaluated. Clinical success was defined as absence of signs and symptoms of hemorrhage for at least 30 day following embolization.ResultsActive extravasation was demonstrated in three cases. Angiographic abnormalities related to a GI tract tumor were identified on 35 of 37 angiograms, including tumor neovascularity (n=21), tumor enhancement (n=24), and luminal irregularity (n=5). In the absence of active extravasation, empiric embolization with particles and/or coils was performed in 25 procedures. Cessation of hemorrhage (ie, clinical success) occurred more frequently when empiric embolization was performed (17 of 25 procedures; 68%) than when embolization was not performed (two of nine; 22%; P=.03). Empiric embolization resulted in clinical success in 10 of 11 patients with acute GI bleeding (91%), compared with seven of 14 patients (50%) with chronic GI bleeding (P=.04). No ischemic complications were encountered.ConclusionsIn patients with advanced malignancy, in the absence of active extravasation, empiric transcatheter arterial embolization for treatment of GI hemorrhage from a direct tumor source demonstrated a 68% short-term success rate, without any ischemic complications.  相似文献   
102.
Background and Aim:  The rate of fibrosis progression per year can predict the time for the development of cirrhosis in chronic hepatitis C (CHC). We assessed the rate of fibrosis progression and the predictors of disease severity in Indian CHC patients.
Methods:  Of the 355 treatment-naïve, histologically-proven CHC patients, the precise duration of infection (from the time of exposure to HCV until liver biopsy) could be determined in 213 patients (age = 41.6 ± 14.7 years, male : female = 139 : 74, genotype 3 = 75%). The rate of fibrosis progression per year was calculated. The correlation of the advanced degree of fibrosis and age, duration of infection, age at the onset of infection, sex, mode of infection, hepatitis C virus (HCV) genotype, histological activity index (HAI), and the presence of diabetes mellitus were studied.
Results:  The median rate of fibrosis progression per year was 0.25 (0.0–1.5) fibrosis units. The fibrosis progression rate was higher in patients who acquired infection at > 30 years of age, those < 30 years (0.33 vs 0.15; P  < 0.001), and those who acquired HCV infection with a history of blood transfusion than with other modes of transmission (0.25 vs 0.19; P  = 0.04). The median time to progress to cirrhosis was 16 years. The multivariate analysis found that the HAI score (odds ratio [OR]= 14.03; P  < 0.001) and the duration of infection > 10 years (OR = 4.83; P  < 0.001) correlated with severe liver disease (fibrosis ≥ 3).
Conclusion:  The median rate of fibrosis progression per year in Indian CHC patients is 0.25 fibrosis units. A higher HAI and longer duration of infection are associated with a significant risk of advanced liver disease, and merit early therapeutic interventions.  相似文献   
103.
104.
Glycosidic residues involved in human sperm-zona pellucida binding in vitro   总被引:3,自引:1,他引:2  
Glycosidic residues of the mammalian zona pellucida (ZP) are known to be involved in sperm binding, suggesting the presence of complementary carbohydrate binding sites on spermatozoa. However, in previous studies, in which sperm suspensions were incubated with monosaccharides, no inhibitory effect was observed. Results of studies in which sperm were treated shortly after swim-up suggest that the use of non-capacitated cells may explain the apparently conflicting results. In the present report, we studied the effect of preincubation of capacitated spermatozoa with different monosaccharides on their ability to bind to ZP. After 5 h under capacitating conditions, spermatozoa were incubated in medium with or without a monosaccharide, resuspended in fresh medium and used for hemizona (HZ) binding assay. When ZH were incubated with spermatozoa treated with N-acetyl-D- glucosamine, D-mannose, D-fucose, L-fucose or D-galactose, a significant decrease in the number of spermatozoa bound was observed (level of inhibition: 62, 58, 82, 68 and 48% respectively) while treatment of spermatozoa with D-glucose produced no inhibition. Sugar treatment neither altered sperm motility nor the rate of acrosome reaction. These results suggest that N-acetylglucosamine, mannose, fucose and galactose residues are involved in human sperm-zona pellucida binding in vitro.   相似文献   
105.
Provocative angiography in obscure gastrointestinal bleeding   总被引:2,自引:0,他引:2  
Obscure gastrointestinal (GI) bleeding is relatively common but difficult to manage. By definition, diagnosis of a specific etiology is particularly challenging. We report the diagnostic use of provocative angiography in a patient with recurrent obscure GI bleeding. Although provocative angiography led to localization of bleeding and allowed specific treatment (placement of a 2-mm long, 0.010-inch diameter platinum coil, resulting in cessation of bleeding for 2 months), ultimately, the use of provocative angiography delayed specific diagnosis in our patient. We conclude that provocative angiography is a potentially powerful adjunct in the management of obscure GI bleeding, but that caution is required when using it. Provocative angiography should be reserved for patients who have had adequate imaging studies with negative results.  相似文献   
106.
The family of glycoproteins called gp70 includes molecules that are the main constituent of murine C-type viral envelopes, and some that are expressed as mendelian constituents of thymocyte plasma membranes in the absence of virions. To investigate further the relation of viral gp70s to plasma- membrane gp70s we compared peptide maps of gp70s derived by immunoprecipitation from cells infected with chosen viruses and from various thymocytes and leukemiacells known to express one or more of three immunogenetically defined gp70 types: Glx-gp70, X-gp70, and O-gp70. Maps of gp70 from cultured cells infected with ecotropic and xenotropic viruses were distinguishable from one another, and in general resembled gp70 maps prepared directly from ecotropic and xenotropic virions respectively. Maps of gp70s immunoprecipitated from thymocytes of five mouse strains and from two A strain T-cell leukemias also fell into two distinguishable and generally corresponding patterns. Thus peptide-mapping substantiates earlier conclusions that viral gp70s and plasma-membrane gp70s inherited independently of virus-production are highly related or identical molecules. The gp70 maps of thymocytes from B6, B6-G(+IX), 129, and A mice formed a group resembling the map from cultured cells infected with xenotropic virus. Thymocytes from AKR mice, and the two A strain leukemias, gave gp70 maps conforming more to the second pattern, that of cultured cells infected with ecotropic virus. This second pattern probably comprises at least two gp70 types, one of which is X-gp70. Our data indicate that the G(IX)-gp70 and O-gp70 sub-species of gp70 expressed in the cell populations we have studied are coded by xenotropic viral genomes, and X-gp70 by ecotropic viral genomes.  相似文献   
107.
The epidemiology of infections with 5 human herpesviruses (HHVs) (HHV-6, HHV-7, HHV-8, varicella zoster virus [VZV], and Epstein-Barr virus [EBV]) was investigated during the first year after solid organ transplantation in 263 patients who received oral ganciclovir or valganciclovir prophylaxis. HHV-6B DNAemia was uncommon, HHV-6A DNAemia was not observed, and HHV-7 DNAemia was prevalent. HHV-6 and HHV-7 DNAemia were not significantly associated with cytomegalovirus (CMV) disease, although a trend toward higher incidence of CMV disease was observed in HHV-6 DNAemic patients. VZV and HHV-8 DNAemia were not detected. EBV infection was common, although incidence of high-level EBV DNAemia was low, especially in patients who received valganciclovir prophylaxis. EBV-related posttransplant lymphoproliferative disease was not observed up to 12 months after transplantation. Compared with historic data, data from the present study suggest that antiviral prophylaxis may lower the incidence, prevalence, or level of DNAemia for infection with HHV-6, HHV-8, VZV, and EBV but not for infection with HHV-7.  相似文献   
108.
109.
The purpose of this article was to review the literature and provide guidelines on the use of radiation protection for patients in the dental setting. There are limited published data on the effects of low radiation doses such as those used in dental radiology. Most of the evidence is subject to bias, with risk models extrapolated from higher dose models such as studies of the Hiroshima bomb survivors. However, the lack of evidence does not denote the absence of risk, as there is no established ‘safe’ level of radiation exposure. All imaging utilizing ionizing radiation carries a risk for the patient. Hence the patient benefits of imaging must outweigh the potential risk. All diagnostic imaging should adhere to three basic principles, these being justification, optimization and application of dose limits. This article discusses dose reduction techniques and shielding of sensitive organs, particularly the thyroid, during procedures such as intraoral imaging, orthopantomograms and imaging of the pregnant patient.  相似文献   
110.
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