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81.
Diagnosis of deep vein thrombosis using multi-detector helical CT   总被引:1,自引:0,他引:1  
PURPOSE: To evaluate the usefulness of multi-detector helical CT (MDHCT) with contrast medium in the diagnosis of deep vein thrombosis (DVT). Materials and Methods: The bilateral veins of the dorsal pedis in 45 patients (12 men, 33 women; average age, 64 years) under clinical suspicion of DVT were first punctured using 22-G needles. Then CT scanning from the level of the foot to the inferior vena cava was started 20 sec after the initial injection of 200 mL of dilute contrast medium (50 mL nonionic iodinated contrast medium of 300 mgI/mL and 150 mL saline) at a rate of 5 mL/sec. RESULTS: Two patients were excluded because of unsuccessful venous puncture. The average scanning time in 43 patients was 38.5 +/- 7.9 seconds. Images of veins from the foot to the inferior vena cava were clearly demonstrated in each case. MDHCT showed DVT in 32 cases and patent deep vein in 11 cases. Simultaneous venography of the lower extremity in 18 patients clearly visualized DVT at the same level detected by contrast MDHCT. CONCLUSION: MDHCT for the diangosis of DVT has the advantages of wider scanning range, shorter scanning time, and finer Z-axis resolution than the other diagnostic modalities.  相似文献   
82.
The retention indices of 201Tl-SPECT in brain tumors   总被引:1,自引:0,他引:1  
OBJECTIVE: The aim of this study was to assess the utility of 201Tl SPECT in the differential diagnosis of intracranial tumors and to determine the relationship between 201Tl uptake and histological types. METHODS: Thirty-eight patients (19 males and 19 females) with thirty-eight brain tumors were evaluated with 201Tl-SPECT. The early and delayed 201Tl uptake ratio was calculated, and the retention index (RI) was applied as follows; RI = delayed uptake ratio/early uptake ratio. RESULTS: The RI of malignant tumors was higher (0.72 +/- 0.18) than that of benign tumors (0.50 +/- 0.16) and the difference was statistically significant (p = 0.00045). The difference between high-grade glioma (0.80 +/- 0.15) and metastatic tumors (0.64 +/- 0.19) was statistically significant (p = 0.039). CONCLUSION: 201Tl-SPECT may add useful biochemical information and could differentiate malignant brain tumors from benign lesions, but the RI of metastatic tumors varied depending on the organs with the primary lesion and histological types.  相似文献   
83.
The subject was a 65-year-old woman with chest pain. An electrocardiogram revealed T-wave-inversion in leads III, aVF, V1-V5. 99mTc-tetrofosmin myocardial SPECT showed mildly reduced uptake in the anteroseptal wall and the apex. These findings suggested acute myocardial ischemia. Coronary angiography did not show any stenotic lesions, but diffuse coronary ectasia was noted in three vessels. Coronary flow velocity was remarkably reduced on coronary angiography. Epicardial coronary spasm was not provoked by ergonovine loading test. Left ventriculography showed diffuse hypokinesis. 123I-BMIPP myocardial SPECT showed mildly reduced uptake in the anteroseptal wall and the apex on the early images. But 4-hour delayed images showed an increase of 8% in myocardial 123I-BMIPP uptake. We treated this patient with ticlopidine and nicorandil. After drug therapy her symptoms and left ventriculography improved. 123I-BMIPP myocardial SPECT findings on the early images improved, whereas delayed images showed a decrease of 28% in myocardial 123I-BMIPP uptake after two weeks and 36% after four weeks. These dynamic changes in 123I-BMIPP findings might be a reflection of myocardial fatty acid metabolism in patients with acute myocardial ischemia. Delayed 123I-BMIPP myocardial SPECT images are useful for the assessment of fatty acid metabolism.  相似文献   
84.
The ability of autologous nerve segments interposed between allografts, to increase the total nerve-gap distance, was studied. Sciatic nerve allografts were carried out in a rat model. A 15-mm nerve gap was repaired with a 25-mm nerve graft (interposed group: allo-auto-allograft; control group: allo-allo-allograft). Cyclosporin was given for 12 weeks. Nerve regeneration was evaluated using the weight of the anterior tibial muscle and histologic, morphometric and immunohistochemical analyses at 12, 13, 14, 15, 16, 20, and 24 weeks. Nerve regeneration in the interposed group was statistically significantly better than that in the control group. The authors concluded that a nerve allograft with interposed autograft may enhance nerve regeneration in this model, because of the migration of host-derived Schwann cells into the graft from not only the proximal and distal host nerve stumps, but also the interposed autograft.  相似文献   
85.
AIM: The aim of this study was to examine the cumulative risk of pouchitis following restorative proctocolectomy for UC and FAP in Japanese patients, and to assess the response to medical treatment and its outcome. PATIENTS AND METHODS: 521 patients with UC and 117 FAP patients underwent proctocolectomy and received a J-shaped IPAA at our department of surgery. We investigated these patients using PDAI for the diagnostic criteria of pouchitis. RESULTS: Pouchitis occurred in only 32 UC patients (6.1%). The cumulative risk of developing pouchitis for a UC patient was 7% at 5 years after and 12% at 10 years after surgery. The medical treatment of acute pouchitis was usually oral metronidazole (250 mg twice daily) for 2 weeks or oral ciprofloxacin (200 mg thrice daily) in patients who could not tolerate metronidazole. Single episodes of pouchitis occurred in 21 patients (65.6%) and chronic or frequent relapses of pouchitis in 11 patients (34.4%). Three patients (9.4%) required re-ileostomy. Two patients (6.3%) required pouch excision. There were no patients with complicated dysplasia. CONCLUSION: The cumulative risk of pouchitis in Japanese UC patients is lower than that of western countries.  相似文献   
86.
Dysregulated transforming growth factor beta (TGF‐β) signaling is associated with a spectrum of osseous defects as seen in Loeys‐Dietz syndrome, Marfan syndrome, and Camurati‐Engelmann disease. Intriguingly, neurofibromatosis type 1 (NF1) patients exhibit many of these characteristic skeletal features, including kyphoscoliosis, osteoporosis, tibial dysplasia, and pseudarthrosis; however, the molecular mechanisms mediating these phenotypes remain unclear. Here, we provide genetic and pharmacologic evidence that hyperactive TGF‐β1 signaling pivotally underpins osseous defects in Nf1flox/?;Col2.3Cre mice, a model which closely recapitulates the skeletal abnormalities found in the human disease. Compared to controls, we show that serum TGF‐β1 levels are fivefold to sixfold increased both in Nf1flox/?;Col2.3Cre mice and in a cohort of NF1 patients. Nf1‐deficient osteoblasts, the principal source of TGF‐β1 in bone, overexpress TGF‐β1 in a gene dosage–dependent fashion. Moreover, Nf1‐deficient osteoblasts and osteoclasts are hyperresponsive to TGF‐β1 stimulation, potentiating osteoclast bone resorptive activity while inhibiting osteoblast differentiation. These cellular phenotypes are further accompanied by p21‐Ras–dependent hyperactivation of the canonical TGF‐β1–Smad pathway. Reexpression of the human, full‐length neurofibromin guanosine triphosphatase (GTPase)‐activating protein (GAP)‐related domain (NF1 GRD) in primary Nf1‐deficient osteoblast progenitors, attenuated TGF‐β1 expression levels and reduced Smad phosphorylation in response to TGF‐β1 stimulation. As an in vivo proof of principle, we demonstrate that administration of the TGF‐β receptor 1 (TβRI) kinase inhibitor, SD‐208, can rescue bone mass deficits and prevent tibial fracture nonunion in Nf1flox/?;Col2.3Cre mice. In sum, these data demonstrate a pivotal role for hyperactive TGF‐β1 signaling in the pathogenesis of NF1‐associated osteoporosis and pseudarthrosis, thus implicating the TGF‐β signaling pathway as a potential therapeutic target in the treatment of NF1 osseous defects that are refractory to current therapies. © 2013 American Society for Bone and Mineral Research.  相似文献   
87.

Purpose

Nephron sparing surgery is an effective surgical option in patients with renal cell carcinoma. Laparoscopic partial nephrectomy involves clamping and unclamping techniques of the renal vasculature. This study compared the postoperative renal function of partial nephrectomy using an estimation of the glomerular filtration rate (eGFR) for a Japanese population in 3 procedures; open partial nephrectomy in cold ischemia (OPN), laparoscopic partial nephrectomy in warm ischemia (LPN), and microwave coagulation using laparoscopic partial nephrectomy without ischemia (MLPN).

Materials and Methods

A total of 57 patients underwent partial nephrectomy in Yokohama City University Hospital from July 2002 to July 2008. 18 of these patients underwent OPN, 17 patients received MLPN, and 22 patients had LPN. The renal function evaluation included eGFR, as recommended by The Japanese Society of Nephrology.

Results

There was no significant difference between the 3 groups in the reduction of eGFR. eGFR loss in the OPN group was significantly higher in patients that experienced over 20 minutes of ischemia time. eGFR loss in LPN group was significantly higher in patients that experienced over 30 minutes of ischemia time.

Conclusion

This study showed that all 3 procedures for small renal tumor resection were safe and effective for preserving postoperative renal function.Key Words: eGFR, Partial nephrectomy, Renal function, Laparoscopic partial nephrectomy  相似文献   
88.
Forensic Toxicology - Since the 1980s, the detection sensitivity of mass spectrometers has increased by improving the analysis of drugs in hair. Accordingly, the number of hair strands required for...  相似文献   
89.
Forensic Toxicology - Various forms of cannabidiol (CBD)-containing products are sold in Japan. CBD is easily converted to mixtures of ?9-tetrahydrocannabinol (?9-THC) and its isomer,...  相似文献   
90.

Purpose

The anterior cruciate ligament (ACL) rarely heals spontaneously after rupture. Mesenchymal stem cells (MSCs) contribute to healing in various tissues, therefore, they may also have a key role in healing after ACL rupture. The purpose of this study was to investigate the properties of MSCs in ruptured ACLs.

Methods

Human ACL samples were harvested from patients undergoing primary ACL reconstruction, and samples were classified by the number of days post rupture (phase I <21 days; phase II 21–56 days; phase III 57–139 days phase IV ≥140 days). We evaluated the characteristics of MSCs, such as colony-forming capacity, differentiation potential and cell-surface markers.

Results

There was a tendency for high colony-forming capacity during phases I and II, which tended to decrease in phase III. Chondrogenic, adipogenic and osteogenic differentiation potential was maintained until phase II but decreased in phase III. Most surface-epitope expression was consistent from phase I to III: positive for CD44, CD73, CD90 and CD105; negative for CD11b, CD19, CD34, CD45 and human leukocyte antigen-D-related (HLA-DR). The presence of these surface markers proved the existence of MSCs in ruptured ACL tissue.

Conclusions

Our results suggest that colony-forming and differentiation potential decrease over time. It is important to consider changes in properties of MSCs and use ACL tissue in the acute phase of rupture when biological manipulation is required.  相似文献   
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