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71.
Hagiwara  M; Pincus  SM; Chen  IL; Beckman  BS; Fisher  JW 《Blood》1985,66(3):714-717
A human renal carcinoma from a patient with erythrocytosis, serially transplanted into athymic nude mice, was grown in primary monolayer cell cultures. After reaching confluency, the cultured cells formed multicellular hemicysts (domes), which became more abundant as the cultures approached saturation density. Erythropoietin (Ep) production by this renal carcinoma in culture was only slightly increased at the time of semiconfluency but showed a marked increase after the cultures reached confluency, in parallel with dome formation. Dibutyryl adenosine 3',5'-cyclic monophosphate significantly (P less than .01) stimulated Ep production and dome formation in the semiconfluent and confluent cultures of the renal carcinoma.  相似文献   
72.
de Lange  EE; Shaffer  HA  Jr; Daniel  TM; Kron  IL 《Radiology》1987,165(1):45-47
Disruption of a cervical esophagogastric or esophagocolonic anastomosis shortly after surgery is a common complication, and fistula drainage from the leaking anastomosis may be prolonged. Narrowing of the anastomosis apparently contributes to the development and maintenance of the fistula. Fluoroscopically guided balloon dilation of anastomotic strictures was performed in three patients with anastomotic leaks. Preliminary results suggest that the procedure is safe and promotes healing of the fistula.  相似文献   
73.
Singer  SJ; Rubin  IL; Strauss  KJ 《Radiology》1987,164(3):871-872
Atlantoaxial subluxation is common in persons with Down syndrome. For radiologic screening to be valid, accurate measurement of the atlantoaxial distance (AAD) must be obtained from radiographs of the cervical spine. A radiopaque millimeter scale has been designed to simplify accurate measurement of the AAD from these radiographs.  相似文献   
74.

Background

Recurrence patterns or survival in colorectal cancer patients might differ according to inferior mesenteric lymph node (IMLN) metastasis. However, few studies have compared para-aortic lymph node (PALN) metastasis and IMLN metastasis. The aim of the current study is to identify survival and recurrence patterns in patients with sigmoid colon and rectal adenocarcinoma with either PALN or IMLN metastasis and to evaluate the prognostic significance of PALN and IMLN metastasis.

Methods

A retrospective study involving 3076 patients with stage III and IV sigmoid and rectal cancer, who underwent curative surgery between January 2000 and December 2009, was performed. Clinicopathologic features, recurrence patterns, and survival outcomes of 27 patients with PALN metastasis were compared with those of 47 patients with IMLN metastasis. Patients with both IMLN and PALN metastasis were included in the PALN+ group.

Results

After curative resection, there was no significant difference in the 5-year disease-free and overall survival rates between the PALN+ and IMLN+ groups (27.5% vs. 29.8%, p = 0.24, and 37% vs. 39.2%, p = 0.19, respectively). Furthermore, there were no significant differences in recurrence rate (PALN+ group, 70.4%; and IMLN+ group, 63.8%; p = 0.69) or recurrence patterns.

Conclusions

The results suggest that IMLN metastasis, similar to PALN metastasis, is associated with adverse oncologic outcomes and has prognostic significance. Therefore, it is preferable that IMLN metastasis should be considered under the category of systemic metastasis (M1).  相似文献   
75.
ObjectiveBaseline amyloid burden in mild cognitive impairment (MCI) has been linked to conversion to Alzheimer’s disease (AD), but the comparison of baseline and longitudinal changes in amyloid burden for predicting AD remains unresolved. The objectives of this study aimed to compare the prognostic ability of baseline and longitudinal changes in amyloid burden in MCI patients. MethodsSeventy-five individuals with MCI were recruited and examined annually by clinical interviews for a mean follow-up of 24 months (range, 11.6–42.0). [18F]Florbetaben positron emission tomography (PET) scans were performed. T1-weighted 3D volumes were acquired for co-registration, and to define regions of interest. We examined whether baseline and longitudinal amyloid burden changes can improve AD conversion by Cox proportional hazard model analysis and receiver operating characteristic (ROC) curve analysis. ResultsCox proportional hazards model analysis showed that baseline amyloid burden was significantly associated with increased risk of conversion to AD (hazard ratio [HR]=10.0; 95% confidence interval [CI], 1.15–85.39; p=0.04), but longitudinal amyloid burden changes was not (HR=0.2; 95% CI, 0.02–1.18; p=0.07). When predicting AD, longitudinal amyloid burden changes had better ROC accuracy of 65.2% (95% CI, 48.4–82.0) than baseline amyloid burden of 59.6% (95% CI, 40.3–79.0), without statistical significance in pairwise comparison. ConclusionA single baseline amyloid PET could be sufficient in the prediction of AD conversion in MCI.  相似文献   
76.
77.
78.
Tegtmeyer  CJ; Kellum  CD; Kron  IL; Mentzer  RM  Jr 《Radiology》1985,157(3):661-665
Percutaneous transluminal angioplasty of lesions located at the bifurcation of vessels, especially the aortic bifurcation, has been considered contraindicated because of possible occlusion or embolization of the contralateral vessel. With the evolution of angioplasty techniques and the development of new balloon catheters, these lesions can now be successfully treated with the kissing balloon technique. This technique was used to dilate 61 atherosclerotic vascular lesions in 32 patients with vascular insufficiency. The procedure was successful in 58 atherosclerotic stenoses in 30 patients. Because of the high blood flow and large size of these vessels, beneficial clinical results can be anticipated following successful dilatation. Follow-up study, extending for as long as 53 months, suggests the durability of the procedure and that the kissing balloon technique should be considered as a viable alternative to surgery in dilatable lesions of the aortic bifurcation.  相似文献   
79.
Uchida  N; Aguila  HL; Fleming  WH; Jerabek  L; Weissman  IL 《Blood》1994,83(12):3758-3779
Hematopoietic stem cells (HSCs) are believed to play a critical role in the sustained repopulation of all blood cells after bone marrow transplantation (BMT). However, understanding the role of HSCs versus other hematopoietic cells in the quantitative reconstitution of various blood cell types has awaited methods to isolate HSCs. A candidate population of mouse HSCs, Thy-1.1lo Lin-Sca-1+ cells, was isolated several years ago and, recently, this population has been shown to be the only population of BM cells that contains HSCs in C57BL/Ka-Thy-1.1 mice. As few as 100 of these cells can radioprotect 95% to 100% of irradiated mice, resulting long-term multilineage reconstitution. In this study, we examined the reconstitution potential of irradiated mice transplanted with purified Thy-1.1lo Lin-Sca-1+ BM cells. Donor-derived peripheral blood (PB) white blood cells were detected as early as day 9 or 10 when 100 to 1,000 Thy-1.1lo Lin-Sca-1+ cells were used, with minor dose-dependent differences. The reappearance of platelets by day 14 and thereafter was also seen at all HSC doses (100 to 1,000 cells), with a slight dose-dependence. All studied HSC doses also allowed RBC levels to recover, although at the 100 cell dose a delay in hematocrit recovery was observed at day 14. When irradiated mice were transplanted with 500 Thy-1.1lo Lin-Sca-1+ cells compared with 1 x 10(6) BM cells (the equivalent amount of cells that contain 500 Thy-1.1lo Lin-Sca-1+ cells as well as progenitor and mature cells), very little difference in the kinetics of recovery of PB, white blood cells, platelets, and hematocrit was observed. Surprisingly, even when 200 Thy1.1lo Lin-Sca- 1+ cells were mixed with 4 x 10(5) Sca-1- BM cells in a competitive repopulation assay, most of the early (days 11 and 14) PB myeloid cells were derived from the HSC genotype, indicating the superiority of the Thy-1.1lo Lin-Sca-1+ cells over Sca-1- cells even in the early phases of myeloid reconstitution. Within the Thy-1.1lo Lin-Sca-1+ population, the Rhodamine 123 (Rh123)hi subset dominates in PB myeloid reconstitution at 10 to 14 days, only to be overtaken by the Rh123lo subset at 3 weeks and thereafter. These findings indicate that HSCs can account for the early phase of hematopoietic recovery, as well as sustained hematopoiesis, and raise questions about the role of non-HSC BM populations in the setting of BMT.  相似文献   
80.
BACKGROUND: Many attempts have been made to improve the treatment success rate of chronic bacterial prostatitis (CBP). However, no treatment modality has achieved complete cure. The growth and development of the prostate is under direct hormonal control, and it is possible that prostatitis may be directly influenced by its hormonal milieu in a similar fashion to benign prostatic hyperplasia and prostate cancer. Therefore, the effects of androgen deprivation on the treatment of CBP were investigated in rats. METHODS: Experimental CBP was induced in one hundred, male Wistar rats by instillation of bacterial suspension (Escherichia coli Z17, O2: K1: H-) containing 1 x 10(8) CFU/ microL into the prostatic urethra. Microbiologically and histologically proven CBP was demonstrated in 62% (62 of 100) of the rats after 4 weeks of bacterial instillation. The 62 rats demonstrating CBP were randomly divided into five groups: control; castration; finasteride; estrogen; and levofloxacin groups. All drug treatments were conducted over a period of 4 weeks. RESULTS: Microbiological cultures and histological findings of the prostate and urine samples demonstrated reduced bacterial growth and improved inflammatory responses in all four experimental groups compared with the control group. The castration and estrogen groups showed coherent trends of decrease in bacterial growth and improvements in prostatic inflammation compared with the control group, but not to a statistically significant degree (P > 0.05). However, the finasteride and levofloxacin groups did show statistically significant decreases in bacterial growth and improvements in prostatic inflammation compared with the control group (P < 0.05). CONCLUSION: These results suggest that androgen deprivation is an effective modality in CBP treatment. In particular, the finasteride treatment reduced the severity of CBP in the animal model without reducing the systemic testosterone level. The combination of finasteride and levofloxacin maybe one of the effective treatment modalities for CBP.  相似文献   
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