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11.
Intestinal schistosomiasis japonica: CT-pathologic correlation   总被引:1,自引:0,他引:1  
  相似文献   
12.
Acute transverse myelitis is a rare clinical manifestation of Coxsackie virus infection which cause acute and progressive debilitating illness associated with loss of spinal cord function in the affected patients. A 62 year-old female developed symptoms of rapidly progressive paraplegia with sensory loss. On spinal MRI, T2 sagittal image showed increased signal intensity with cord swelling at T11-L2 level and 8 folds or greater rise of Coxsackie virus B4 neutralizing antibody titers was observed in the CSF. There is only one previous report of acute transverse myelitis caused by Coxsackie virus B4 infection to our knowledge. The presence of specific viral antibody titers change in the CSF and a corresponding spinal cord lesion are sufficient to suggest a causal relationship between the virus and the illness. This article is a case report of an unusual acute transverse myelitis caused by Coxsackie virus B4 infection.  相似文献   
13.
The results of treating 12 consecutive patients with unresectable colorectal hepatic metastases with a hepatic arterial infusion of high-dose Adriamycin, 100–120 mg/m2, using hepatic venous isolation (HVI) and charcoal hemoperfusion (CHP) are reported herein. Adriamycin was administered over 5–15 min under extracorporeal drug elimination by HVI-CHP. HVI was percutaneously accomplished by either the double-balloon technique using a Fogarty occlusion catheter (8/22F) or a balloon-tipped catheter (16F). During the infusion, isolated hepatic venous blood was filtered by CHP and pumped into the left axillary vein. There were no lethal complications, and good hemodynamic tolerance to HVI-CHP was confirmed. Tumor liquefaction accompanied by a sharp decrease in serum carcinoembryonic antigen levels by more than 50% of pretreatment levels was observed in 6 of the 12 patients 1 month after treatment. Apart from chemical hepatitis, which developed in 11 (92%) of the patients, the Adriamycin toxicities were well controlled following the development of nausea and vomiting in 2 patients (17%), leukopenia <2,000/mm3 in 3 (25%), and gastric ulcer in 1 (8%). These results indicate that this method is a safe and useful procedure for otherwise hazardous high-dose intraarterial chemotherapy in patients with unresectable hepatic tumors.  相似文献   
14.
Multiple-bandwidth photoacoustic tomography   总被引:3,自引:0,他引:3  
Photoacoustic tomography, also referred to as optoacoustic tomography, employs short laser pulses to generate ultrasonic waves in biological tissues. The reconstructed images can be characterized by the convolution of the structure of samples, the laser pulse and the impulse response of the ultrasonic transducer used for detection. Although the laser-induced ultrasonic waves cover a wide spectral range, a single transducer can receive only part of the spectrum because of its limited bandwidth. To systematically analyse this problem, we constructed a photoacoustic tomographic system that uses multiple ultrasonic transducers simultaneously, each at a different central frequency. The photoacoustic images associated with the different transducers were compared and analysed. The system was tested by imaging both mouse brains and phantom samples. The vascular vessels in the brain were revealed by all of the transducers, but the image resolutions differed. The higher frequency detectors provided better image resolution while the lower frequency detectors delineated the major structural traits with a higher signal-noise ratio.  相似文献   
15.
Committing embryonic stem cells to early endocrine pancreas in vitro   总被引:12,自引:0,他引:12  
A panel of genetic markers was used to assess the in vitro commitment of murine embryonic stem (ES) cells toward the endoderm-derived pancreas and to distinguish insulin-expressing cells of this lineage from other lineages such as neuron, liver, and yolk sac. There are two nonallelic insulin genes in mice. Neuronal cells express only insulin II, whereas the pancreas expresses both insulin I and II. Yolk sac and fetal liver express predominately insulin II, small amounts of insulin I, and no glucagon. We found that ES-derived embryoid bodies cultured in the presence of stage-specific concentrations of monothio-glycerol and 15% fetal calf serum, followed by serum-free conditions, give rise to a population that expresses insulin I, insulin II, pdx-1 (a pancreas marker), and Sox17 (an endoderm marker). Immunohistochemical staining shows intracellular insulin particles, and its de novo production was confirmed by staining for C-peptide. Most, but not all, of the insulin+ or C-peptide+ cells coexpress glucagon, demonstrating a differentiation pathway to pancreas rather than yolk sac or fetal liver. Addition of beta-cell specification and differentiation factors activin beta B, nicotinamide, and exendin-4 to later-stage culture increased insulin-positive cells to 2.73% of the total population, compared with the control culture, which gave rise to less than 1% insulin-staining cells. These findings suggest that stepwise culture manipulations can direct ES cells to become early endocrine pancreas.  相似文献   
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17.
Lyt phenotype of in vitro generated alloreactive cytotoxic T lymphocytes (CTL) and their precursors in B6-Lyt-1.1 (Thy-1.2, Lyt-1.1, Lyt-2.2) congenic strain of mice was studied. The generation of CTL in vitro was completely abrogated by pretreatment of responder cells with antisera to Thy-1.2, Lyt-1.1 and Lyt-2.2 antigens and complement. Mixing of anti-Lyt-1.1-pretreated cells with anti-Lyt-2.2-pretreated cells did not restore CTL generation indicating that both Lyt antigens are expressed on the same precursor cell population. The effect of anti-Lyt sera was specific because the generation of CTL was prevented only when cells from strains possessing appropriate Lyt alleles were pretreated. CTL were eliminated by lysis with anti-Thy-1.2 serum and strongly reduced by anti-Lyt-1.1 and anti-Lyt. 2.2 sera. Nevertheless, a small but significant proportion of CTL was insensitive to lysis with anti-Lyt sera. These data indicate that a phenotype of precursor cells and of majority of CTL is Thy-1.2+ Lyt-1.1+ Lyt-2.2+.  相似文献   
18.
Several species of helicobacter have been isolated from laboratory mice, including H. bilis, H. hepaticus, H. muridarum, H. rodentium, and H. typhlonius, which appear to be the most common. The most widely used published method for molecular detection of these agents is PCR amplification of a conserved region of 16S rRNA, but differential speciation requires restriction enzyme digestion of the amplicons. This study was undertaken to determine PCR conditions that would simultaneously and specifically identify each of the five common species without restriction enzyme analyses. First, we designed novel and specific PCR primers for H. bilis, H. hepaticus, H. muridarum, H. rodentium, and H. typhlonius, using sequences from the heterologous regions of 16S rRNA. Because of comigration of amplified products, we next identified P17, an H. bilis-specific protein; P25, an H. hepaticus-specific protein; and P30, an H. muridarum-specific protein by screening genomic DNA expression libraries of each species. Primers were designed from these three genes, plus newly designed, species-specific 16S rRNA primers for H. rodentium and H. typhlonius that could be utilized for a five-plex PCR. The sizes of the amplicons from H. bilis, H. hepaticus, H. muridarum, H. rodentium, and H. typhlonius were 435, 705, 807, 191, and 122 bp, respectively, allowing simultaneous detection and effective discrimination among species.  相似文献   
19.
Association of psoriasis vulgaris with HLA-C is not equally strong in different human populations. It has not yet been studied in Polish patients at DNA level, but only by serology that is inadequate for HLA-C. Therefore, we examined the distribution of HLA-C alleles by means of low resolution PCR-SSP in 102 Polish psoriatics and 123 healthy controls. We have found significantly higher representation of HLA-Cw*06 (odds ratio, 18.73; P(cor)<0.001) and significantly lower representation of HLA-Cw*07 (odds ratio, 0.41; P(cor)<0.038) in patients than in controls. Association of HLA-Cw*06 with psoriasis was even stronger in early age at onset (0-20 years) group: odds ratio, 77.71; P(cor)<0.001. Therefore, our population seems to belong to those with strong association of psoriasis with HLA-Cw*06.  相似文献   
20.
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