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71.
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.  相似文献   
72.
Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) solely induce arthritis in mice. High titers of anti-GPI Abs are found in some patients with rheumatoid arthritis (RA), but their pathogenic role remains elusive. The aim of this study was to evaluate the pathogenic role of anti-GPI Abs in cynomolgus monkeys. IgG fractions were separated from sera of anti-GPI Abs-positive RA patients and healthy subjects and directly injected into the metacarpophalangeal joints of 4 cynomolgus monkeys. At day 16, the joints were harvested and examined histologically and immunohistochemically. The expression of C5a receptor (C5aR) molecule in the synovium was quantified by real-time PCR using cDNA from monkey joints. In monkey joints, IgG including anti-GPI Abs resulted in recruitment of granulocytes and mononuclear cells, strong deposition of human IgG on the articular surface, and overexpression of C5aR, but no joint swelling. No infiltrated cells or IgG deposition were observed in monkeys injected with IgGs from healthy subjects. Our results suggest that IgG fraction from RA patients including anti-GPI Abs may play a crucial role in the generation of synovitis in monkeys, although the pathogenesis of anti-GPI Abs in RA patients is still uncertain.  相似文献   
73.
Summary To investigate whether the feline CD 4 (fCD 4) molecules are involved in infections of highly lymphotropic feline immunodeficiency virus (FIV) isolates, we expressed fCD 4 stably on Crandell feline kidney cells andFelis catus whole foetus 4 cells by transfection of a cDNA encoding the fCD 4 glycoprotein, and then infected them with TM 1 and TM 2 strains of FIV, which are unable to infect these cells productively. In spite of fCD 4 being expressed on these cells, no virus production was observed. This result indicates that fCD 4 expression alone cannot induce a productive infection of the FIV TM 1 and TM 2 strains.  相似文献   
74.
The purposes of the present study were to examine the response of the skin blood flux (SBF) in the paralyzed lower limbs of persons with spinal cord injury (PSCI) and to clarify the relationship between the SBF and core temperature during prolonged arm exercise. Eight male PSCI with lesions from T6 to L5 and six male control subjects (CS) participated in this study. The subjects rested for 60 min and then performed arm-cranking exercise at 20 W for 30 min at 25 °C. The tympanic membrane temperature (T ty) and SBF in the anterior thigh (SBFT) and in the posterior calf (SBFC) were continuously measured throughout the experiment. The SBFC did not change in either PSCI or CS during the experiment. The SBFT in four PSCI with high lesions (T6 to T12), remained unchanged during exercise. The SBFT in the other four PSCI with low lesions (T12 to L5, SBFT+) began to elevate markedly when the T t, exceeded a threshold temperature of 36.69 °C. The pattern of increase of SBFT in SBFT+ was similar to that in CS, although onset of the increase in SBFT was delayed and the peak of SBFT during exercise was significantly lower in comparison with the CS. We consider that these differences between the SBFT+ and CS were largely attributable to the lowerT ty in the former group, which took a prolonged time to reach the threshold of 36.69 °C.  相似文献   
75.
Polymeric conjugates of adriamycin (ADR) ( 2 ) or daunomycin (DM) ( 3 ) were synthesized by reaction of the drugs with the copolymer of divinyl ether and maleic anyhdride (DIVEMA) ( 1 ). The content of ADR moieties in the DIVEMA conjugate ( 4 ) could be varied depending on the reaction conditions up to 35,8 wt.-%. Considering the low toxicity and the high possibility of renal excretion, DIVEMA with M?w of 7000 and M?w/M?n = 1,6 was used for the conjugation. The rate of drug release from the conjugate was determined under physiological conditions by reversed phase HPLC. Within 14 days only 15% of the attached ADR was released from conjugate 4 . The antitumor activity of the conjugates was tested in vitro and in vivo against mouse P388 leukemia. Conjugate 4 proved to be 28 times less active than ADR in vitro, which could be explained from the slow drug-release. On the contrary 50% of the leukemic mice treated by 4 survived more than 60 days, whereas no mice given ADR alone or the admixture of ADR and DIVEMA survived 30 days. An antitumor activity of the polymeric conjugate better than that of the free drug was also observed in vivo with DM. Such a polymeric effect can be attributed either to the change in body distribution, the difference in pharmacokinetics, or the slow drugrelease.  相似文献   
76.
Sex, age and 21 routine liver function assays were analyzed by stepwise selection and the best-of-all-possible-combinations method to identify a small group of assays valuable in establishing which liver cirrhosis (LC) patients have a high risk of hepatocellular carcinoma (HCC), when alpha-fetoprotein (AFP) is not elevated. Data was obtained from 115 HCC and 122 LC patients on admission. Tumor size correlated with AFP (0.73), alkaline phosphatase (ALP, 0.47), leucine aminopeptidase (LAP, 0.42), lactic dehydrogenase (LDH, 0.42), and the glutamic oxaloacetic transaminase (GOT)/glutamic pyruvic transaminase (GPT) ratio (GOT/GPT, 0.41). The mean of the correct diagnosis rates (CDR) of HCC and LC utilizing AFP as the sole parameter (89%) was markedly higher than those of the other parameters. The best-of-all-possible-combinations method presented a more powerful combination than stepwise selection. The best combination of 7 parameters (LAP, GOT/GPT, choline esterase, one-hour erythrocyte sedimentation rate, age, albumin/globulin ratio, and total bilirubin) presented a mean CDR of 80%, HCC CDR of 77%, and false positive rate of 18%. LC patients statistically diagnosed as having HCC by these 7 parameters are proposed as high risk patients. Fourteen (78%) of 18 HCC patients who were AFP-negative were statistically diagnosed. This analysis can be applied to LC patients to distinguish those that should be followed closely by imaging diagnostic techniques.  相似文献   
77.
Pulmonary dysfunction is a significant complication following allogeneic hematopoietic stem cell transplantation (HSCT), and is associated with significant morbidity and mortality. Effective antimicrobial prophylaxis and treatment strategies have increased the incidence of noninfectious lung injury, which can occur in the early posttransplant period or in the months and years that follow. Late-onset noninfectious pulmonary complications are frequently encountered, but diagnostic criteria and terminology for these disorders can be confusing and therapeutic approaches are suboptimal. As a consequence, inaccurate diagnosis of these conditions may hamper the appropriate data collection, enrollment into clinical trials, and appropriate patient care. The purpose of this review is to clarify the pathogenesis and diagnostic criteria of representative conditions, such as bronchiolitis obliterans syndrome and bronchiolitis obliterans organizing pneumonia, and to discuss the appropriate diagnostic strategies and treatment options.  相似文献   
78.
We demonstrate directed differentiation of telencephalic precursors from mouse embryonic stem (ES) cells using optimized serum-free suspension culture (SFEB culture). Treatment with Wnt and Nodal antagonists (Dkk1 and LeftyA) during the first 5 d of SFEB culture causes nearly selective neural differentiation in ES cells ( approximately 90%). In the presence of Dkk1, with or without LeftyA, SFEB induces efficient generation ( approximately 35%) of cells expressing telencephalic marker Bf1. Wnt3a treatment during the late culture period increases the pallial telencephalic population (Pax6(+) cells yield up to 75% of Bf1(+) cells), whereas Shh promotes basal telencephalic differentiation (into Nkx2.1(+) and/or Islet1/2(+) cells) at the cost of pallial telencephalic differentiation. Thus, in the absence of caudalizing signals, floating aggregates of ES cells generate naive telencephalic precursors that acquire subregional identities by responding to extracellular patterning signals.  相似文献   
79.
Carbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined. The results showed that lymphatic invasion, lymph node metastasis, and peritoneal metastasis correlated with staining with lectins that bind galactose/N-acetylgalactosamine residues (Gal/GalNAc) such as Maclura pomifera (MPA), Arachis hypogaea (PNA), Helix pomatia (HPA), and Vicia villosa (VVA). In contrast, hepatic metastasis correlated with staining with Anguilla anguilla lectin (AAA), anti-LewisX (LEX-2), anti-sialyl Lewisa (NS19-9), and anti-sialyl-dimeric LewisX (FH-6) MAbs, all of which bind preferentially to fucosylated carbohydrate chains. The five-year survival rate of patients was related to the staining of cancers with MPA, HPA, FH-6 or NS19-9, and MPA- and FH-6 staining were independent prognostic factors. We conclude that carbohydrate expression profiles of cancer cells are relevant to the route of tumor cell dissemination, metastatic pattern as well as prognosis of colorectal cancer.  相似文献   
80.
Effects of sinusoidal grating stimulus presented outside the classical receptive field (CRF) on neuronal responses were studied in the primary visual cortex of anaesthetized cats. Among 101 cells electrophysiologically recorded, the predominant effect of the stimulus in the receptive field surround (SRF) was the suppression of responses to the CRF stimulation, and the SRF grating suppressed them up to 56% of the responses (44% suppression) to the CRF stimulus alone. The strong suppression was observed more often in layer II/III cells than in other layers and in complex cells more often than in simple cells. The modulatory effects by SRF stimulus might be enhanced by the cortical recurrent excitation particularly in the superficial layers. We also examined whether the modulation by the surround grating exhibits a differential effect according to the presence or absence of figure-ground segregation in the stimulus configuration. For this purpose, effects of stimulus configuration with orientation-, direction-contrast or relative spatial phase difference between CRF and SRF stimuli (figure-ground segregated configuration) were compared with those of uniform configuration of stimulus (non-segregated configuration). There was a population of cells, which exhibited significantly stronger suppression with non-segregated configuration than with figure-ground segregated configuration. Such differential modulation of response by the SRF stimulus in the primary visual cortex is a possible basis of perceptual figure-ground segregation.  相似文献   
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