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1.
A case of cystadenocarcinoma of the liver is reported. The patient was a 73-year-old woman in whom a tumor was detected in the lateral segment of the liver during a health examination. Ultrasonograms and computed tomograms showed a multilocular cystic mass. Magnetic resonance imaging (MRI) showed a multilocular lowintensity mass, including a high-intensity portion and a portal branch compressed by the tumor. MRI with gadolinium showed an enhanced cyst wall. The cystic part of the tumor became smaller and the solid part became larger over a 1-month period, indicating that the tumor was malignant. Subsegmentectomy (S3) was performed and cystadenocarcinoma with cystadenoma was diagnosed by histopathological examination. Identification of changes in the appearance of a tumor should be helpful for the differential diagnosis of cystadenoma and cystadenocarcinoma.  相似文献   
2.
Humoral hypercalcemia of malignancy (HHM) in neoplastic syndrome has been most commonly reported in squamous cell carcinoma. Gallbladder carcinoma with HHM is uncommon. In this report, we describe a male case of gallbladder carcinoma with marked hypercalcemia and a high level of serum parathyroid hormone-related peptide (PTHrP). An immunohistochemical examination using PTHrP was also positive.  相似文献   
3.
Xamoterol, a partial-beta 1 agonist, was administered orally (100 mg, twice daily) to healthy volunteers (n = 8) and to patients with heart failure (n = 8) for one week. The density (Bmax) and affinity (Kd) of lymphocyte beta-receptors were lower in the patients with heart failure than in the healthy volunteers (Bmax = 931 +/- 214 vs 1466 +/- 373 sites/cell, and Kd = 0.60 +/- 0.11 vs 1.07 +/- 0.14 nM). During treatment with xamoterol, Bmax (7169 +/- 3768 and 7749 +/- 3807 sites/cell) and Kd (6.01 +/- 3.84 and 9.06 +/- 4.66 nM) increased strikingly (p less than 0.01) in both groups. For 12 months, xamoterol (100 mg bd) was given in the same manner to 10 patients with dilated cardiomyopathy. The long-term effects after three and 12 months were assessed. Xamoterol reduced the cardiothoracic ratio from 57 +/- 6% to 55 +/- 5% after three months and 54 +/- 5% after 12 months of treatment (both p less than 0.05), and increased exercise tolerance from 5 +/- 2 min to 7 +/- 2 min and to 7 +/- 2 min (p less than 0.01, p less than 0.05). Echocardiographic fractional shortening increased from 13 +/- 6% to 20 +/- 8% (p less than 0.01) and to 20 +/- 10% (p less than 0.05). Pulmonary wedge pressure during exercise at the same work load decreased from 40 +/- 12 mmHg to 25 +/- 9 mmHg (p less than 0.01) in three months; whereas pulmonary wedge pressures during exercise or at rest in 12 months were unchanged. Exercise heart rate decreased from 118 +/- 9 beats/min to 106 +/- 6 beats/min in three months (p less than 0.01), but was unchanged in 12 months. Bmax and Kd of the beta-receptors increased from 1024 +/- 413 sites/cell and 0.67 +/- 0.27 nM to 1976 +/- 497 sites/cell and 1.60 +/- 0.42 nM (both p less than 0.01), respectively, in three months, and 1584 +/- 650 sites/cell (NS) and 1.21 +/- 0.54 nM (p less than 0.05), respectively, in 12 months. It is concluded that xamoterol improves exercise tolerance, hemodynamics and resolves subjective symptoms for certain patients with dilated cardiomyopathy by its actions as a beta-agonist and beta-antagonist during longterm treatment.  相似文献   
4.
Background. A membrane oxygenator consisting of a microporous polypropylene hollow fiber with a 0.2-μm ultrathin silicone layer (cyclosiloxane) was developed. Animal experimental and preliminary clinical studies evaluated its reliability in bypass procedures.

Methods. Five 24-hour venoarterial bypass periods were conducted on dogs using the oxygenator (group A). In 5 controls, bypass periods were conducted using the same oxygenator without silicone coating (group B). As a preliminary clinical study, 14 patients underwent cardiopulmonary bypass with the silicone-coated oxygenator.

Results. Eight to 16 hours (mean, 12.2 hours) after initiation of bypass, plasma leakage occurred in all group B animals, but none in group A. The O2 and CO2 transfer rates after 24 hours in group A were significantly higher than at termination of bypass in group B (p < 0.005 and p < 0.03, respectively). Scanning electron microscopy of silicone-coated fibers after 24 hours of bypass revealed no damage to the silicone coating of the polypropylene hollow fibers. In the clinical study, the oxygenator showed good gas transfer, acceptable pressure loss, low hemolysis, and good durability.

Conclusions. This oxygenator is more durable and offers greater gas transfer capabilities than the previous generation of oxygenators.  相似文献   

5.
Purpose: We examined whether bone marrow-derived dendritic cells (DCs) could induce antitumor immunity when a chemotherapeutic drug was added. Methods: CT26 (a murine colon cancer cell line syngeneic with BALB/c) and CT26-bearing mice were treated with mitomycin C (MMC) intraperitoneally (i.p.). Next, mice immunized with a coinjection of DCs and MMC-treated CT26 (i.p.) were given an intradermal inoculation of CT26. Finally, CT26-bearing mice were treated with MMC (i.p.) with or without DCs, given peritumorally. Results: Although the inoculated tumor was not rejected in the control mice, CT26 was rejected in 50% of the mice injected with MMC alone. Apoptosis was observed in the MMC-treated CT26 cells in vitro and in vivo. Immunization with DCs and apoptotic CT26 cells, but not with apoptotic CT26 alone, gave protection against tumor challenge in 7 of 13 mice. A significantly higher level of cytotoxic T-cell activity and interferon-γ production was seen in the protected mice. When MMC (i.p.) treatment was followed by peritumoral DC injection in the CT26-bearing mice, remarkable therapeutic effects were observed. Conclusion: DCs can collaborate with chemotherapy-induced apoptotic tumor cells and elicit improved antitumor immunity, probably through the acquisition of tumor-associated antigens from apoptotic tumor cells. Received: January 7, 2002 / Accepted: September 3, 2002 Acknowledgments. We thank Dr. Kazuo Kinoshita for his useful advice on using flow cytometry. This research was partly supported by the Ministry of Education, Culture, Sports, Science and Technology (No. 11671160). Reprint requests to: S. Yamasaki  相似文献   
6.
We have shown that autoallergic sialadenitis develops in C3H/He (H-2k) mice thymectomized 3 days after birth and then immunized at 4 or 6 weeks of age with a homogenate of the submandibular salivary gland emulsified in Freund's complete adjuvant. Significant inflammatory changes did not develop in other inbred strains, such as BALB/c (H-2d), and C57BL/6 (H-2b) mice, examined by the same experimental protocol, or in the control groups, i.e. animals thymectomized at day 3 but not immunized, and animals not thymectomized but immunized. The cellular infiltrates observed in C3H/He mice with sialadenitis consisted of small and medium-sized lymophocytes stained with anti-Thy-1.2 antibody (the major proportion positive with anti-L3T4 and the lesser, with anti-Lyt 2). Anti-salivary duct antibodies were detected frequently in the sera of the C3H/He mice with sialadenitis.  相似文献   
7.
We report the first case of intraosseous epithelioid malignant peripheral nerve sheath tumor (MPNST) occurring in the phalanx. The patient was a 50-year-old Japanese man with an intramedullary lytic lesion of the proximal phalanx. Microscopically, the tumor was composed of epithelioid cells or polygonal cells, forming large cell nests with central necrosis. Most tumor cells were diffusely and strongly immunopositive for S-100 protein and vimentin, and negative for cytokeratin, epithelial membrane antigen, carcinoembryonic antigen, alpha-smooth muscle actin, and HMB-45. Laminin-positive material was discontinuously demonstrated between the individual tumor cells. Electron microscopy showed prominent external lamina. Our case indicated that laminin is useful for differentiating epithelioid MPNST from metastatic carcinoma and malignant melanoma.  相似文献   
8.
In situ localization of tau mRNA in developing rat brain   总被引:6,自引:0,他引:6  
A microtubule-associated protein, tau, promotes microtubule assembly, forms characteristic short cross-bridges (less than 20 nm) between microtubules, and switches isoforms from juvenile to adult at the end of the first postnatal week in the rat brain. The developmental expression of tau was studied in rat central nervous system, mainly the cerebrum and cerebellum, by in situ hybridization. Tau mRNAs were localized in a wide variety of neural cells. The expression of tau mRNAs in the spinal cord appeared to precede that in the brain, and the expression in the brainstem appeared to precede that in the cerebral cortex and cerebellum. On neural cells throughout the cortical plate of the cerebral cortex, tau mRNAs were expressed in large amounts during the first postnatal week, but by the third postnatal week the expression had become reduced. In the cerebellum, tau mRNAs were enriched in granule cells. The expression in the internal granular layer peaked during the second and third postnatal weeks, and the relatively high level of expression persisted to young adulthood. Thin section transmission electron microscopic study revealed that the proportion of neighboring microtubules in parallel fiber axons of cerebellar granule cells with the distance less than 20 nm was as low as 10% at the end of the first postnatal week, but this proportion increased to as high as 35% at the end of the second postnatal week. Northern blot analysis showed that tau mRNAs were congruent to 6 kb as was reported previously, and those detected in the first postnatal week were three- to five-fold more abundant and approximately 0.2 kb smaller than those detected in the second or third postnatal weeks. The data suggest that (a) tau mRNAs are abundantly expressed in a wide variety of neurons in the central nervous system at the stage of neurite formation, and (b) tau mRNAs are expressed in more basal levels at later stages, but may be important in the formation and maintenance of characteristic microtubule bundles typically found in parallel fiber axons and in other axons.  相似文献   
9.
Langerhans cell granulomatosis (LCG) is characterized by a mixture of Langerhans cells and eosinophils in varying proportions. The characteristic morphology of Langerhans cells have already been described in many articles, but little attention has been paid to inflammatory cells. We examined six cases of Langerhans cell granulomatosis, which had originally been diagnosed as eosinophilic granuloma. Inflammatory cells present in LCG showed hypersegmentation. Twenty percent to 70% of eosinophils had three or more segmented nuclei, and 10-25% of neutrophils had five or more segmented nuclei. Such findings have never been described, and we believe hypersegmentation to be a feature of LCG. Furthermore, we emphasize that eosinophils in LCG mimic neutrophils in ethanol-fixed preparations, and thus may be a pitfall in making a diagnosis in cytology and intraoperative consultation.  相似文献   
10.
We have established a set of transgenic mouse lines in which the HLA-DRA gene was expressed in different cell types. In one line (DRα-24), DRαEβb molecules were expressed on thymic medullary and cortical epithelial cells and all lineages of bone marrow-derived antigen-presenting cells (APC) except for thymic macrophages. By contrast, expression of the molecules in another line (DRα-30) was found on thymic medullary and cortical epithelial cells but not on bone marrow-derived APC in the thymus and periphery. To evaluate the role of thymic epithelial cells in acquisition of T cell tolerance, comparative analysis of DRα-24 and DRα-30 was performed. In DRα-30, T cells expressing TcR Vβ5 and Vβ11 were eliminated to comparable levels to those in DRα-24, suggesting that expression of the DRαEβb molecules on thymic epithelial cells are sufficient for clonal deletion of the self-superantigen-reactive T cells. In addition, CD4+ T cells from DRa-30 as well as those from DRα-24 were tolerant to DRα-derived peptide/I-Ab complex expressed on spleen cells from DRα-24 even in the presence of exogenous interleukin-2. These observations suggest that expression of the DRα chain in thymic epithelial cells could induce T cell tolerance directed toward naturally processed DRα-derived peptide bound to I-Ab molecules, probably via clonal deletion of the self-reactive T cells.  相似文献   
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