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991.
The nucleotide sequence of the Anaplasma centrale 16S rRNA gene was determined and compared with the sequences of ehrlichial bacteria. The sequence of A. centrale was closely related to Anaplasma marginale by both level-of-similarity (98.08% identical) and distance analysis. A species-specific PCR was developed based upon the alignment data. The PCR can detect A. centrale DNA extracted from 10 infected bovine red blood cells in a reaction mixture. A. centrale DNA was amplified in the reaction, but not other related ehrlichial species.  相似文献   
992.
The aim of this study was to assess the efficacy and safety of thin membranes of polychlorovinylidene (PCV) or polyurethane (PU) as covering materials for Gianturco stents in the treatment of severe tracheal stricture caused by intraluminal tumor. Manufactured Gianturco stents covered with PCV or PU membrane were used to treat six malignant and one benign tracheal stricture. The initial results, complications, clinical follow-up, bronchoscopic findings, and three autopsy microscopic examinations were reviewed. Informed consent was obtained after the nature of the treatment had been fully explained before every procedure. The stents successfully dilated the tracheal strictures, providing immediate relief of respiratory symptoms in all patients with no major complications. During the follow-up period, the covering materials prevented tumor ingrowth until death or intraluminal granuloma formation. Autopsies proved that no histological change occurs in the tracheal mucosa in response to the presence of PCV or PU; however, ulcer formation occurred in one patient and penetration of the stent struts into the tracheal wall in two. Bloody sputum with ulcer formation, minimal granuloma formation at the distal end of the stent, and abnormal bacterial load in the sputum were long-term complications. The Gianturco stent covered with PCV or PU membrane is a useful option as a palliative treatment for malignant and an emergent salvage for benign tracheal stricture, because both materials are thinner and less voluminous than the others. However, the indications for its use are limited to patients with poor prognoses, because hemoptysis, granuloma formation, and bacterial propagation remain problematic.  相似文献   
993.
Parathyroid hormone (PTH) increases serum calcium (Ca) by enhancing bone resorption and renal Ca reabsorption. However, detailed mechanisms of enhanced bone resorption by PTH remain to be elucidated. Although PTH has been shown to increase the expression level of osteoblastic matrix metalloproteinase (MMP)-13 in vitro, only limited results are available regarding the in vivo regulation of MMP expression. In the present study, we have examined expression levels of MMPs in PTH-infused rats. Infusion of 1.5 or 2.0 nmol/kg/day rat PTH(1–34) for 3 days resulted in a dose-dependent increase in serum Ca. PTH infusion also decreased serum phosphate levels and increased urinary excretion of Ca and phosphate. Infusion of PTH for 7 days resulted in less severe hypercalcemia and hypophosphatemia. Urinary Ca and phosphate excretion in rats infused for 7 days was less than that in rats infused for 3 days. Northern blot analysis showed that PTH infusion increased the expression level of MMP-13 in calvaria, although it did not affect MMP-2 expression. Furthermore, the time-course and severity of hypercalcemia and hypercalciuria correlated with the expression level of MMP-13. In situ hybridization also showed that PTH infusion increased the expression level of MMP-13 in femora. These results indicate that PTH enhances MMP-13 expression in vivo and suggest that PTH stimulates bone resorption at least partly by enhancing MMP-13 expression. Received: June 5, 2000 / Accepted: January 12, 2001  相似文献   
994.
BACKGROUND: Interferon (IFN)-alpha shows certain clinical effects on the treatment of renal cell carcinoma. The purpose of the present study was to investigate its direct effects and to compare the responses among different human renal cancer cell lines. METHODS: Three cell lines, ACHN, RCC10RGB and OS-RC-2, were incubated with IFN-alpha and evaluated using MTT assay for cell proliferation and two-color flow cytometry for cell-cycle-specific cyclin expressions coupled with DNA ploidy analysis. RESULTS: Interferon-alpha inhibited cell proliferation and caused cell accumulation at S and G2/M phases. However, IFN-alpha induced no significant change in cyclins D1, E, A or B1 expression. Interestingly, cell kinetic changes caused by IFN-alpha were different among cell lines. Cell proliferation was suppressed most in ACHN, then RCC10RGB and least in OS-RC-2. Comparing DNA histograms, ACHN showed distinct increase of G2/M cells associated with elevation of late S cells. RCC10RGB showed a predominant increase of whole S cells accompanied with a slight increase of G2/M. OS-RC-2 showed a modest increase of S cells with a little change of G2/M cells. Chronological observation revealed that S-phase increase and proliferative inhibition appeared on day 1 and day 3, respectively, in ACHN and RCC10RGB, and on day 5 in OS-RC-2. CONCLUSIONS: Interferon-alpha induced substantial cell kinetic interference directly in the tested human renal carcinoma cell lines. The degree of change was different according to the nature of the cell line. It may partly indicate the variety of the efficacy of IFN-alpha treatment against renal cancers.  相似文献   
995.
We report a patient with fatal hepatitis B virus (HBV) reactivation after treatment for chronic graft-versus-host disease (GVHD) following allogeneic peripheral blood stem cell transplantation to treat chronic myelogenous leukemia. The presence of antibodies to hepatitis B surface antigen (HBsAb) prior to transplantation indicated previous HBV infection. Liver damage first developed 8 months after transplantation with the disappearance of HBsAb. Hepatitis B antigen was first noted during an examination of liver damage that occurred 22 months after transplantation. Retrospective examination of serum by real-time detection polymerase chain reaction (RTD-PCR) revealed HBV in both the first and second episodes of liver damage (89 copies/mL and 2 x 10(6) copies/mL, respectively). HBV may have been reactivated, leading to fatal liver damage in this HBsAb-positive patient. We propose that RTD-PCR-based analysis should be performed to diagnose liver dysfunction after hematopoietic stem cell transplantation.  相似文献   
996.
997.
Abstract: To clarify the role of dose escalation of donor leukocyte infusion (DLI) in the treatment of relapsed leukemia after allogeneic bone marrow transplant (BMT), data from 100 patients were collected from 46 facilities in Japan and analyzed with respect to indications and infused cell dose. Complete remission (CR) was achieved in 11 of 12 (91%) patients with relapsed chronic myelogenous leukemia (CML) in the chronic phase, 3 of 11 (27%) with CML in the acute phase, 8 of 21 (38%) with acute myelogenous leukemia (AML), 6 of 23 (25%) with acute lymphoblastic leukemia (ALL), and 5 of 11 (45%) with myelodysplastic syndrome (MDS). The probability of remaining in CR at 3 years was 82% in CML patients in the chronic phase, but 0% in those with CML in the acute phase, 7% in those with AML, 0% with ALL, and 33% with MDS. Acute graft‐versus‐host disease (GVHD) (≥2) developed in 31 of 89 (34%) patients with human leukocyte antigen identical related donors and was fatal for 7 (7%). A leukocyte dose of 1 × 107/kg of recipient body weight with CML in the chronic phase, 3 × 107/kg of recipient body weight with MDS, and 1 × 108/kg of recipient body weight with acute leukemia appeared to be optimal as an initial dose of DLI. However, the minimal dose of leukocyte developing fatal GVHD was 7 × 107/kg of recipient body weight. These suggest that a relatively small dose of DLI ranging from 1 × 107/kg to 5 × 107/kg of recipient body weight should be administered initially then the infused escalating dose 2 or 3 months later in patients with CML in the chronic phase and MDS. However, a large number of leukocytes around 1 × 108/kg are needed to induce graft versus leukemia effects in patients with acute leukemia despite a 7% fatality in GVHD.  相似文献   
998.
The Long–Evans Cinnamon rat, an animal model of Wilson’s disease, is an inbred mutant strain with spontaneous hepatitis isolated from Long–Evans rats. The copper concentration in the brains of Long–Evans Cinnamon rats at 4 weeks of age was lower than that of controls, but higher than that of controls at 20 weeks of age. We investigated the tyrosine hydroxylase and 5-hydroxytryptamine immunoreactive fiber densities in the brains of Long–Evans Cinnamon rats aged 4, 10, and 20 weeks by immunohistochemistry, comparing them with Long–Evans Agouti rats used as controls. Tyrosine hydroxylase immunoreactive fiber densities in the cingulate cortex, hippocampus and cerebellum in Long–Evans Cinnamon rats were significantly lower than those of Long–Evans Agouti rats at 4 and 10 weeks of age. On the other hand, 5-hydroxytryptamine immunoreactive fiber densities in the cingulate cortex, caudate-putamen, hypothalamus, and hippocampus in Long–Evans Cinnamon rats were significantly higher than those of controls at 4, 10 and 20 weeks of age. In the cingulate cortex and caudate-putamen, 5-hydroxytryptamine immunoreactive fiber densities became gradually higher with age. The number of aberrant 5-hydroxytryptamine immunoreactive fibers in the cingulate cortex, caudate-putamen, hypothalamus and hippocampus in LEC rats was significantly higher than that of controls. The number of another type of aberrant 5-hydroxytryptamine immunoreactive fibers, which were detected only at 20 weeks of age in the caudate-putamen in LEC rats was significantly higher than that of controls. These results suggest that age-dependent changes in copper concentrations of Long–Evans Cinnamon rats were related to changes in monoaminergic neuron systems.  相似文献   
999.
Protocols for prevention of cerebral ischemic attacks caused by hyperventilation resulting from crying, as observed in perioperative pediatric moyamoya patients, were evaluated. The first protocol involved the use of sedation when staff were setting up the intravenous lines, performing neuroimaging studies, and controlling postoperative pain. The second involved the use of wound-handling techniques designed to ease postoperative wound care; these included steristrip closure, use of paraffin gauze and not using adhesive tapes. We compared 14 and 11 surgical cases handled before and after the protocols were introduced, respectively. The number of patients with perioperative cerebral infarction decreased from 2 to 0. Appropriate sedation reduced the incidence of transient ischemic attacks from 28.6% to 3.7%. The average postoperative hospital stay was similarly reduced, from 21.3 days to 16.1 days, as a consequence of the reduced incidence of complications. It is concluded that the perioperative risks can be minimized when invasive procedures are managed according to our protocols. Received: 22 June 1999 Revised: 15 December 1999  相似文献   
1000.

Background

Despite the literature indicating adverse interactions between warfarin and cytotoxic agents, whether such an interaction occurs when warfarin and gefitinib are used concomitantly is unknown. We analyzed the prevalence of the concomitant use of warfarin and gefitinib, and the incidence of prothrombin time-international normalized ratio (PT-INR) alterations or adverse interactions in concomitant users of warfarin and gefitinib.

Methods

We conducted a retrospective study of patients with non-small cell lung cancer treated at the Kitasato University Hospital who received concomitant warfarin and gefitinib between September 2002 and January 2007. Medical information, including the indication for warfarin use, warfarin dosing and dosing changes, and exposure to gefitinib were collected from computerized databases and medical records.

Results

Twelve (4.1%) of 296 patients treated with gefi— tinib received warfarin. PT-INR elevation occurred in 6 patients (50.0%). Two (16.7%) of the 12 patients had liver metastases. Liver dysfunction was associated with PT-INR elevation (P = 0.0100).

Conclusion

As there is a possibility of PT-INR abnormalities occurring during the concomitant use of gefitinib and warfarin, clinicians should be aware of this interaction. Because of the potentially severe consequences of this interaction, close monitoring of PT-INR and warfarin dose adjustment are recommended for patients receiving warfarin and gefitinib, especially during the first 2 weeks in the beginning of warfarin therapy.  相似文献   
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