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61.
The efficacy of lung cancer screening should not be evaluated by the survival rate of lung cancer patients but by lung cancer mortality in a certain population because the survival rate can be greatly affected by several types of bias. Randomized controlled trials that were conducted during the 1970s and 1980s in Europe and the United States failed to prove the efficacy of lung cancer screening in decreasing the mortality rate; but recently the results of case-control studies in Japan have revealed that undergoing currently available screening decreases the risk of lung cancer deaths by 30%–60%. A system is now being created in Japan whereby the guidelines regarding cancer screening will continue to be updated. The preliminary reports concerning lung cancer screening using thoracic computed tomography revealed that not only the detection rate of lung cancer but also the survival rate of detected lung cancer patients were surprisingly high. However, the presence of some potential bias in these studies cannot be ignored; therefore, it is still unknown whether there is actual efficacy. Several randomized controlled trials are presently in progress overseas, but the interim results were not favorable. A randomized controlled trial should therefore immediately be started in Japan as well.  相似文献   
62.
An osteoblastic cell line (HOS cells) produces a prominent osteoid matrix with mineralization. Fibroblasts, on the other hand, do not exhibit this mineralization. To evaluate the degree of mineralization, we added calcein to the culture medium and then observed the culture wells by using an image analyzer. The calcein uptake into the cell/matrix layer was detected in the HOS cells but not in the fibroblasts. The calcein uptake was also quantified in situ by using an image analyzer, which revealed high levels in the HOS cells, which correlated well with the calcium content of the mineralized matrix. Rat marrow cells were also cultured in media containing calcein, fetal bovine serum, -glycerophosphate, L-ascorbic acid 2-phosphate, and with or without dexamethasone. With the dexamethasone, the cells exhibited osteogenic differentiation that resulted in mineralized matrix formation after about 10 days. The matrix formation coincided with the appearance of calcein uptake into the cell/matrix layer, with the amount of calcein uptake increasing with time. By contrast, the culture without the dexamethasone did not exhibit matrix formation and the calcein uptake was negligible. In the case of both HOS cell and rat marrow cell cultures in vitro, calcein did not affect expressions of their alkaline phosphatase activity or osteocalcin production. Furthermore, histologic observation revealed that rat marrow cells subcultured with calcein could show osteogenic ability after in vivo implantation. These results suggest that the current method of detecting calcein uptake in a culture allows the monitoring of the osteogenic capacity of cultured cells, as well as the measurement of the amount of mineralization produced by the osteogenic cells. Given that osteogenic cultured cells/mineralized matrices are used in bone reconstruction surgery, the in situ monitoring method is invaluable in that it allows us to evaluate the osteogenic capacity of in vitro constructs.  相似文献   
63.
Changes in bone turnover markers during 14-day 6° head-down bed rest   总被引:1,自引:0,他引:1  
Osteoporosis caused by exposure to microgravity represents a serious clinical concern, but the mechanisms have yet to be fully elucidated. The present research aimed to elucidate the effects of microgravity environments on bone turnover, with a specific focus on changes in bone resorption markers such as type I collagen cross-linked N-telopeptides (NTx) and deoxypyridinoline (Dpyr), for which scant data are available regarding detailed time course. Methods using 6° head-down bed rest were utilized to simulate a microgravity environment. Eleven adult male volunteers underwent 6° head-down bed rest for 14 days; measurements were made of serum and urine Ca concentrations, in addition to osteocalcin (OC), bone alkaline phosphatase (ALP), NTx, and Dpyr as bone turnover markers. By the end of bed rest, concentrations of bone ALP had significantly increased, but OC displayed a tendency toward decrease. Concentrations of Dpyr significantly increased from day 6, remaining elevated until the end of bed rest. Concentrations of NTx significantly increased on day 13 and at the end of bed rest. Serum and urinary concentrations of Ca increased significantly at the end of bed rest. Bone ALP represents a relatively early marker of osteoblast differentiation at the matrix maturation phase and OC is a late marker in osteoblast differentiation at the calcification phase. The present results therefore suggest an absolute increase in bone resorption and normal or reduced bone formation, together causing prominent uncoupling and rapid bone loss after simulated microgravity. Moreover, the present results suggest that bone resorption is enhanced at an early stage of exposure to microgravity environments.  相似文献   
64.
We investigated the possibility of using computer analysis of high-resolution CT images to radiologically classify the shape of pulmonary nodules. From a total of 107 HRCT images of solid, solitary pulmonary nodules with prior differentiation as benign (n=55) or malignant (n=52), we extracted the desired pulmonary nodules and calculated two quantitative parameters for characterizing nodules: circularity and second central moment. Using discriminant analysis for two thresholds in differentiating malignant from benign states resulted in a sensitivity of 76.9%, a specificity of 80%, a positive predictive value of 78.4%, and a negative predictive value of 78.6%.  相似文献   
65.
Metastatic prostate cancer (PC) is incurable by androgen deprivation therapy alone, due to the presence of androgen-independent/supersensitive cells in hormone-naive PC. A 67-year-old man was diagnosed with PC (Gleason score, 5 + 4) with multiple bone metastases. He was treated by chemohormonal therapy with cisplatin and estramustine phosphate (EMP) followed by maximal androgen blockade, and showed a complete response. As of the time of writing, no clinical or prostate-specific antigen recurrence has been observed for over 15 years, despite cessation of the treatment. This is the first report to indicate a possible cure of metastatic PC by chemohormonal therapy combined with appropriate anti-tumor drugs targeted to both androgen-independent and -dependent clones before the hormone-refractory state.  相似文献   
66.
Osteoporotic fracture in elderly populations is increasing worldwide, but there are few data on the incidence and outcome of osteoporotic fractures, including upper extremity and vertebral fracture, during a certain period in a defined geographic area. The purpose of this study was to determine the incidence of osteoporotic fractures in a particular area: Sado City, Niigata Prefecture, Japan. From January to December 2004, osteoporotic fractures of the vertebra, hip, distal radius, and proximal humerus in Sado City were recorded. The incidence, age, gender, type of fracture (for hip fracture), right or left side (for distal radius, proximal humerus, and hip fracture), place of injury, cause of injury, outcome, hospitalization period, and patient status regarding taking of drugs for osteoporosis treatment were checked for each fracture. The incidence was calculated based on the whole population of Sado City. The incidence per 100,000 population was 232.8, 121.4, 108.6, and 37.1 for fractures of the vertebra, hip, distal radius, and proximal humerus, respectively. The total incidence of these four kinds of fracture was 499.9 per 100,000 persons per year. The average age at the time of injury was 81.4, 77.7, 75.7, and 60.2 years old for fractures of the hip, vertebra, proximal humerus, and distal radius, respectively. As the average age increased, the percentage of fractures that occurred indoors also increased; that is, a higher percentage of hip fractures occurred indoors, followed by fractures of the vertebra, proximal humerus, and distal radius. Most patients were not taking anti-osteoporosis drugs before fractures of the hip or vertebra. We determined the incidence of major osteoporotic fractures in 1 year in a defined geographic area. Our data showed that 81% of hip fracture patients also had a vertebral fracture and that the average age at the time of injury was higher for hip fractures than for vertebral fractures. Therefore, these results suggest that vertebral fracture leads to hip fracture, indicating that early fracture prevention and continuous prevention strategies through positive treatment are of importance in osteoporotic elderly people.  相似文献   
67.
PURPOSE: We evaluated the results of extracorporeal shock wave lithotripsy (ESWL) in a large number of cases with upper urinary tract calculi, and reported the strategy how to improve the efficacy and safety of ESWL. PATIENTS AND METHOD: Eight hundred fifteen patients with renal calculi and 1,204 patients with ureteral calculi were treated using a piezoelectric ultrasound-guided lithotriptor, Toshiba ESL-500A. Auxiliary measures were needed in 51 cases (2.5%) and 1,968 cases (97.5%) were treated by in situ procedures. ESWL was performed with the optimal positioning of the patient and under the continuous monitoring by ultrasound system. The visibility of stones was improved by removal of abdominal gas and administration of diuretic agent to dilate the ureter. Cases with urinary tract infection were medicated by antibiotics and the obstruction of the urinary tract was cleared away as soon as possible. RESULTS: Including the cases with residual fragments less than 4 mm, the success rates at one month after the treatment were 97.7% and 98.7% for the renal and ureteral calculi, respectively. The mean numbers of sessions were 1.49 for renal calculi and 1.16 for ureteral calculi. Multiple sessions were required in 24.2% of renal calculi and 12.0% of ureteral calculi. No serious complication has been observed except for three cases, which were sepsis after ESWL, anuria in a solitary kidney, and pyonephrosis caused by Steinstrasse with urinary infection, respectively. CONCLUSION: ESWL using ESL-500A is an efficient treatment of upper urinary tract calculi which has higher pulverization rate and fewer complications in the adequate procedure.  相似文献   
68.
BACKGROUND: In severe acute pancreatitis, multiple organ dysfunction syndrome and infectious complications are contributors to high mortality. Interleukin (IL)-15 is a novel cytokine that shares many biologic properties with IL-2. Serum IL-15 levels have not yet been determined in SAP. METHODS: Serum IL-15 concentrations were measured in 54 patients with severe acute pancreatitis on admission. The relationships with severity, organ dysfunction, infection, and prognosis were analyzed. Utility of IL-15 for the prediction of clinical outcome was evaluated by receiver operator characteristic (ROC) curve analysis. RESULTS: Serum IL-15 levels were increased significantly in severe acute pancreatitis (5.8 +/- 0.5 pg/mL), and they were correlated with Ranson, APACHE II, and Japanese severity score. Serum IL-15 levels were greater in patients with organ dysfunction, patients with infection, and nonsurvivors (P < 05 each). Incidences of organ dysfunction in patients whose IL-15 levels were less than 3.0, 3.0-5.3, and greater than or equal to 5.3 pg/mL, were 8%, 31%, and 89%, respectively (P < .001). Usefulness of IL-15 for the prediction of organ dysfunction was superior to CRP, IL-6, and IL-8, and it was similar to Ranson, APACHE II, and Japanese severity score. Incidences of infection in patients whose IL-15 levels were less than 5.5, 5.5-9.0, and greater than or equal to 9.0 pg/mL, were 7%, 25%, and 50%, respectively (P < .05). Mortality rates in patients whose IL-15 levels were less than 5.5, 5.5-9.0, and greater than or equal to 9.0 pg/mL, were 11%, 25%, and 80%, respectively (P < .001). Usefulness of IL-15 for the prediction of death was superior to CRP, IL-6, and IL-8. CONCLUSIONS: Serum IL-15 level is a useful predictor of the complications (especially organ dysfunction) and mortality in severe acute pancreatitis.  相似文献   
69.
A 59-year-old male patent who had undergone chronic dialysis for 13 years presented with gross hematuria. Radiological examinations showed a cystic renal tumor in the left kidney, multiple renal cysts due to acquired cystic disease of the kidney (ACDK), and a duplicated inferior vena cava (IVC). Although we suspected that the branches of the left IVC might be anormalous with regard to number and location, we could not obtain information about the left renal vein by 3-dimensional computed tomography because of the decreased blood flow in the end-stage kidney. Laparoscopic radical nephrectomy was performed using a transperitoneal approach. We first identified the left IVC and then exposed its surface widely so that we could identify the veins draining into it. We identified and divided two renal veins and also identified an adrenal vein and a gonadal vein draining directly into the left IVC. The enlarged kidney with multiple renal cysts was removed in a purely laparoscopic procedure.  相似文献   
70.
The aging population and an increasing number of hip fractures worldwide have made prevention of hip fractures a matter of importance. The prevalence of hypovitaminosis D in patients with acute hip fracture has been reported widely in recent years, and the vitamin D nutritional status in such reports is usually evaluated based on serum 25-hydroxyvitamin D (25-OHD). The aim of this article is to review the relationship of serum 25-OHD and osteoporotic fracture and the prevalence of 25-OHD insufficiency in patients with hip fracture, including assessment of nutritional status, oral status, activity, and dementia. We conclude that the serum 25-OHD level may be a useful index for risk of hip fracture in elderly people.  相似文献   
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