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排序方式: 共有343条查询结果,搜索用时 11 毫秒
21.
Imaging of rectal cancer   总被引:1,自引:0,他引:1  
Radiologic evaluation of rectal cancer is invaluable in aiding the surgeon, gastroenterologist, and oncologist in the initial and follow-up management of patients with this malignancy. This review highlights recent developments in computed tomography; ultrasonographic, metabolic, and magnetic resonance imaging of rectal cancer; its clinical ramifications; and the direction of future efforts.  相似文献   
22.
Chemokines are a diverse group of small proteins that effect cell signaling by binding to G-protein-coupled, seven-trans-membrane receptors. Our group had found previously that the chemokine receptor CCR1 was present in neurons and dystrophic processes in a small sample of Alzheimer's disease cases. This expanded immunohistochemical study shows that the number of CCR1-positive plaque-like structures in the hippocampus and entorhinal cortex is highly correlated to dementia state as measured by the clinical dementia rating score. CCR1 immunoreactivity is found in dystrophic, neurofilament-positive, synaptophysin-negative neurites that are associated with senile plaques containing amyloid beta peptides of the 1-42 species (Abeta42). CCR1 was not, however, associated with diffuse deposits of Abeta42. There was limited expression of CCR1 in neurofibrillary tangle-bearing neuritic processes. Astrocytes and microglia were typically negative for CCR1. Human brains from age-matched, nondemented individuals rarely displayed either CCR1 or Abeta42 immunoreactivity. Seven other types of dementing neurodegenerative diseases were examined, and all failed to demonstrate CCR1 immunopositivity unless Abeta42-positive plaques were also present. Thus, neuronal CCR1 is not a generalized marker of neurodegeneration. Rather, it appears to be part of the neuroimmune response to Abeta42-positive neuritic plaques.  相似文献   
23.
The results of cessation of therapy (COT) in 64 long-term survivors (disease-free survival of five years or more) of acute lymphoblastic leukemia (ALL) were analyzed to determine the incidence of relapse off therapy. Thirty-seven of the patients had intermittent central nervous system (CNS) prophylaxis. Total follow-up from diagnosis varied from 5.75 to 27.75 years. The median time off therapy was three years (range, 8 months to 26 years). Eighty-six percent (55/64) of the patients continue in their initial remission. Eight patients had relapse, and one patient had a morphologically different leukemia at recurrence. All the relapses occurred between five to eight years from diagnosis and the cumulative rate of relapse for this period was 0.14. There was no significant difference in the rate of relapse for those receiving CNS prophylaxis (0.08) versus those not receiving CNS prophylaxis (0.19). The difference in the relapse rates for boys (0.24) versus girls (0.04) was statistically significant (P=0.04). Isolated testicular relapse (ITR) was not seen in any of the 34 boys. The present study confirms the earlier observations by others that relapse is uncommon in ALL patients remaining in remission longer than seven to eight years. ALL patients treated with intermittent CNS prophylaxis administered throughout the period of maintenance chemotherapy appear to be at no greater risk for relapse off therapy than those treated with high-dose initial cranial irradiation and intrathecal methotrexate. The longer duration of therapy and the use of a repetitive reinduction regimen for maintainance seem to be associated with a decreased risk of ITR after discontinuation of therapy for boys and men. There appears to be a small but definite risk of “second” leukemia in the long-term survivors of leukemia.  相似文献   
24.
Acute mesenteric ischemia, a frequently lethal disease, requires prompt diagnosis and intervention for favorable clinical outcomes. This goal remains elusive due, in part, to lack of a noninvasive and accurate imaging study. Traditional angiography is the diagnostic gold standard but is invasive and costly. Computed tomography (CT) is readily available and noninvasive but has shown variable success in diagnosing this disease. The faster scanning time of multidetector row CT (M.D.CT) greatly facilitates the use of CT angiography (CTA) in the clinical setting. We sought to determine whether M.D.CT-CTA could accurately demonstrate vascular anatomy and capture the earliest stages of mesenteric ischemia in a porcine model. Pigs underwent embolization of branches of the superior mesenteric artery, then imaging by M.D.CT-CTA with three-dimensional reconstruction protocols. After scanning, diseased bowel segments were surgically resected and pathologically examined. Multidetector row CT and CT angiography reliably defined normal and occluded mesenteric vessels in the pig. It detected early changes of ischemia including poor arterial enhancement and venous dilatation, which were seen in all ischemic animals. The radiographic findingsd—compared with pathologic diagnosesd—predicted ischemia, with a positive predictive value of 92%. These results indicate that M.D.CT-CTA holds great promise for the early detection necessary for successful treatment of acute mesenteric ischemia. Presented at the Forty-Sixth Annual Meeting of The Society for Surgery of the Alimentary Tract, Chicago, Illinois, May 14–18, 2005 (oral presentation). Supported by the Karin Grunebaum Research Fellowship, Harvard Medical School (D.E.R.), the German Research Fellowship, German Research Foundation STR 690/1-1 (O.S.), and the Phillip H. Meyers Grant from the Society of Gastrointestinal Radiologists (S.P.T.).  相似文献   
25.

Context:

Blood can save lives; however, it can be a source of transfusion transmitted diseases if proper screening of donated blood is not done. It is now mandatory to screen all donated blood units, whether replacement or voluntary for five transfusion transmitted diseases-namely human immunodeficiency virus (HIV), hepatitis B and C, syphilis, and malaria.

Aims:

The present study was done to study the prevalence of infectious disease markers among donors at the blood bank of a tertiary care center.

Settings and Design:

A total of 53,069 donors donated blood over 11 years. The number of replacement and voluntary donors was 41,710 and 11,359, respectively.

Materials and Methods:

Screening of blood units was done by enzyme-linked immunosorbent assay (ELISA) method for HIV and hepatitis B and C. HIV testing was done using fourth generation ELISA kits. Syphilis was tested by latex agglutination assay and malaria was tested using slide method up to the year 2008-2009 and by rapid immunochromatographic assay after that.

Results:

The mean percentage of these infections per year was found to be 0.2, 1.2, 0.9, 0.3, and 0.002% for HIV, hepatitis B surface antigen (HBsAg), hepatitis C virus (HCV), syphilis, and malarial parasite (MP), respectively.

Conclusions:

The risk of transfusion transmissible infection (TTI) today is low but supply of safe blood depends on proper donor selection and sensitive screening tests.  相似文献   
26.

Purpose

To demonstrate the sensitivity of low temperature synchrotron X-ray diffractometry (SXRD) for detecting solute crystallization in frozen sodium phosphate buffer solutions. To determine the effect of annealing on solute crystallization in frozen solutions.

Materials and Methods

Sodium phosphate buffer solutions, at initial buffer concentrations ranging from 1 to 100 mM (pH 7.4) were cooled to ?50°C. The crystallization of disodium hydrogen phosphate dodecahydrate (Na2HPO4 ?12H2O) was monitored using a laboratory as well as a synchrotron source. At selected concentrations, the effect of annealing (at ?20°C) was investigated.

Results

With the laboratory source, solute crystallization, based on the appearance of one diagnostic peak with a d-spacing of 5.4 Å, was evident only when the initial buffer concentration was at least 50 mM. In contrast, using SXRD, crystallization was detected at initial buffer concentrations down to 1 mM. In addition, the use of a high-resolution 2D detector enabled the visualization of numerous diffraction rings of the crystalline solute. At both 10 and 100 mM buffer concentration, there was no increase in solute crystallization due to annealing.

Conclusion

By using synchrotron radiation, solute crystallization was detected with substantially increased sensitivity, making the technique useful for freeze-drying cycles of practical and commercial importance. Since numerous peaks of the crystalline solute appeared, the technique has potential utility in complex, multi-component systems.  相似文献   
27.
In 1987-88, 281 females from the Government Women's College in Berhampur, Ganfam District, Orissa State in India were surveyed to determine their knowledge and attitude toward family planning (FP). 80% came from urban areas. Educated fathers (72%) had considerable influence over the education of their daughters (p.001). Higher income families (70%) were more able to educate their children than lower income families (30%; p.001). 50% of the students had discussed FP and family ties with their parents. 91% recognized the need for FP. 95% did not favor early marriage (p.02). 66% knew the legal marriage age for females to be 18 years, but only 47% knew it to be 21 for males. In fact, 46% believed the age for males to be 25 years. 24% k new of only 1 FP method, 23% of 2 methods, and 14% of 3 methods. The leading method to be used after marriage according to the students was condoms (16%) followed by IUDs and oral contraceptives (OCs) (6%). The predominant method to use after childbirth was sterilization (13%) followed by IUDs (8%) and condoms and OCs (5%). Most students did not advocate using any method after marriage or after childbirth. 45% mentioned the best time to start FP was after 2 children and 26% after 1 child. Most, (83%) preferred 2 children (p.001) because of better child care and education (37%). 71% felt couples should wait 3 years before having another child. No one believed 1 or 4 years to be adequate birth spacing. Birth spacing was needed in the interest of the mother's health (30%) and for better health of the next child (29%). The mass media provided 50% of the students with FP knowledge. Most (70%) felt that insufficient FP education and basic education were the reasons for unplanned families. 82% believed the FP program would be successful in the future. 68% considered population control important to national development.  相似文献   
28.
29.
Thorotrast-induced cholangiocarcinoma: case report   总被引:1,自引:0,他引:1  
Thorotrast, a contrast medium used extensively before being banned in 1950s, delivers a densely ionizing, high linear energy transfer type of radiation that predisposes to malignancies. We report a case of peripheral cholangiocarcinoma and describe its computed tomographic and magnetic resonance imaging features in a patient who developed it 48 years after exposure to Thorotrast.  相似文献   
30.
The hepatitis G virus (HGV) or GB virus C (GBV-C) was discovered in 1995 as a putative agent of post-transfusion, non-A-E hepatitis. The present study was carried out with the aim to find the prevalence of this virus among various subject groups at risk for parenteral transmission as well as in healthy control subjects both individually and along with other parenterally transmitted hepatitis viruses. Of the 402 subjects tested, 6.22% were positive for the HBsAg surface antigen, 7.21% were positive for HCV RNA while only 2.24% were seen to be carriers of the HGV/GBV-C RNA. All the HGV/GBV-C positive cases were either multi-transfused thalassaemic subjects or hemodialysis patients. None of the healthy control subjects showed presence of the virus. Seven of the HGV/GBV-C positive subjects showed co-infection with one or more additional virological markers. Also, of the 9 HGV/GBV-C positive subjects, 5 showed elevated ALT levels while 4 showed elevated alkaline phosphatase levels. Overall our findings seem to indicate that HGV infections generally are asymptomatic, transient and self-limiting and the virus does not seem to show a very high prevalence among the Indian population.  相似文献   
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