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991.
We investigated cellular and matrix responses of articular cartilage to heat shock. Rat articular cartilage was pretreated at 37 degrees C for 24 h before being exposed to 48 degrees C for 10 min and subsequently incubated at 37 degrees C for 1, 2, 4, 7, 10, and 14 days. Following heat shock, a terminal deoxynucleotidyl transferase nick end labeling assay showed that articular chondrocyte apoptosis appeared at day 1, peaked at day 7, and declined by day 14. Analysis by transmission electron microscopy confirmed that the chondrocytes had characteristic morphological features of apoptosis; immunohistochemical staining revealed that caspase-3 activity in chondrocytes increased, 3-B-3-positive articular chondrocytes decreased in number, and the expression of 3-B-3 native epitope in articular chondrocytes was reduced. Safranin-O staining revealed that depletion of proteoglycans in the matrix was not found in any group. Morphological and biochemical evidence from this study suggested that heat shock at 48 degrees C induced articular chondrocyte apoptosis and suppressed proteoglycan synthesis of articular cartilage in vitro. This study thus provides evidence of the onset of osteoarthritis induced by heat shock and a basis for choosing a temperature at which malignant bone tumor cells can be killed with minimal damage to articular cartilage.  相似文献   
992.
993.
Since thrombotic complications, such as superficial thrombophlebitis and subsequent skin pigmentation, are common after sclerotherapy, we conducted a study to evaluate whether combining sclerotherapy with ligation of varicose veins minimizes complications and what timing for sclerotherapy would be most beneficial-accompanying surgery or several weeks postsurgery. Surgical intervention and compression sclerotherapy were performed consecutively on 111 limbs (group A), and sclerotherapy was performed 28 days after surgical intervention on 87 limbs (group B). The volume of sclerosant used and the frequency of complications (thrombus formation and pigmentation) were analyzed. Plasma levels of thrombin-antithrombin III complex (TAT) and D-dimer (DD), as markers for activation of coagulation, were compared. In group A, the total volume of sclerosant used in patients with complications was significantly higher than that in patients without complications. The frequency of thrombus formation and of pigmentation was significantly lower (p <0.01) in group B (10% and 18%, respectively) than in group A (21% and 37%, respectively). The plasma levels of TAT 7 days after treatment were significantly lower in group B (3.4 +/- 1.2 mg/L) than in group A (4.9 +/- 1.1 mg/L). Performing compression sclerotherapy 28 days after surgical intervention is effective for reducing complications and a good alternative for patients with an underlying hypercoagulable state.  相似文献   
994.
The objective of this study was to compare and contrast the cellular heterogeneity of ovine intervertebral disc (IVD) annulus fibrosus (AF) and nucleus pulposus (NP) cells, synovial fibroblasts (SFs) and articular chondrocytes (ACs) grown in monolayer and alginate bead culture. Phase contrast microscopy of the monolayers indicated that the SF and AF cells, and the AC and NP cells had similar morphologies. Immunolocalisation of type I, II and VI collagen epitopes in the monolayers, however, demonstrated distinct quantitative and relative differences between the SF and AF, and the AC and NP cells. Immunolocalisation of bead-incorporated proteoglycans (PGs) also demonstrated quantitative and qualitative differences between the SF and AF cells. Quantitation of (35)S-bead PGs indicated that the AF cells synthesised significantly higher PG levels than the SFs, and AC cells synthesised significantly higher PG levels than the NP cells. These data were also consistent with the relative metabolic activities and cellular viabilities displayed by each cell type in bead culture. AF cells shared morphological traits with SFs in monolayer, but displayed distinctly different characteristics in bead culture. Similarly, NP cells shared similarities with ACs in monolayer and bead culture, but overall were less metabolically active. Data presented here support the proposal that the AF and NP cells of the ovine IVD should be considered as specialised fibrochondrocytic cells.  相似文献   
995.
 For percutaneous radiofrequency ablation of osteoid osteoma for pain management, we used a standard electrosurgical generator instead of the radiofrequency generator system. First, we used the standard electrosurgical generator to determine the diameter of the coagulated area of normal femurs and humeruses of dogs under general anesthesia and to detect damage to normal tissue around the bone. We then used a standard electrosurgical generator to perform percutaneous radiofrequency ablation of the osteoid osteoma. All three patients were almost pain-free within the first 24 h after the procedure, and they were discharged the day after the operation, being hospitalized for only 2 days. We thus confirmed that percutaneous radiofrequency ablation using a standard electrosurgical generator produced results similar to those achieved with the radiofrequency generator system. Received: August 19, 2002 / Accepted: January 11, 2003 RID="*" ID="*" Offprint requests to: A. Takeda  相似文献   
996.
Sarli L  Costi R  Iusco D  Roncoroni L 《Surgery today》2003,33(11):823-827
Purpose. To evaluate the clinical role of subtotal colectomy with cecorectal anastomosis (CRA) and its postoperative results, based on our surgical experience. Methods. We retrospectively analyzed 26 patients who underwent subtotal colectomy with CRA during an 8-year period (1992–1999) in our university hospital. The indications for CRA were intractable constipation, colon tumors, diverticulitis, Crohns disease, and postactinic colitis. CRA was performed using a new technique of end-to-end antiperistaltic anastomosis. Postoperative and late complications, and functional results, defined as the number of bowel movements per day and quality of life, were evaluated. Results. None of the patients experienced postoperative or late complications. Two patients died from progression of colon cancer. The mean follow-up period was 4.5 years (range 1–8 years). By 1 month after surgery, 58% of the patients were passing frequent bowel movements, and by 1 year after surgery, only 23% of the patients were passing frequent bowel movements. The last follow-up revealed a mean 1.7 bowel movements per day, and only one patient was taking medication for diarrhea. All patients were satisfied with the results of their surgery and reported that their quality of life was good or improved, and even very good in six cases. Conclusions. Subtotal colectomy with our new CRA technique is appropriate for treating inflammatory diseases of the bowel, colon tumors, and intractable constipation in selected patients.  相似文献   
997.
 As data on the relationship between parity and bone mineral density often seem to be controversial, ultimately, a comprehensive research study was thought to be necessary. This study focused on examining the influence of the number of pregnancies on bone mineral density and investigating the relationship between pregnancy and bone mineral density at four sites in postmenopausal women of different age groups. A total of 509 postmenopausal women, varying from 45 to 86 years of age (mean age of 60.85 ± 7.53 years) were considered for the study. A standardized interview was employed to obtain information on demographics, lifestyle, and, reproductive and menstrual histories. Patients were separated into four groups according to the number of pregnancies, i.e., nulliparae (52 patients), one to two parity (66 patients), three to five parity (178 patients), and more than five parity (213 patients). The patients were further classified into two age groups, 40–59 years (233 patients) and 60–80 years (276 patients), respectively. The number of pregnancies was found to range from 0 to 17 (with an overall mean of 5.42 ± 3.68), with 4.29 ± 2.74 (range, 0–16) accounting for live births, while 1.02 ± 1.53 (range, 0–14) were abortions. There were no significant differences among the groups with respect to parameters such as, age, body mass index (BMI), age at menarche, age at menopause, and years since menopause (P > 0.05) in all of the 509 women and in the 40- to 59- and 60- to 80-year groups. When all the patients were considered, the bone mineral density (BMD) values of the spine and the trochanter for the more-than-five-parity group, were found to be significantly lower than those of the other groups (P < 0.05), while the BMD values of the spine and the femur (neck, trochanter) appeared to decrease with increasing parity. In the 40- to 59-year group, the BMD of the spine in both the nulliparae and one-to-two-parity groups was significantly higher than that of the more-than-five-parity group (P < 0.05). No significant differences were found among the groups with respect to the BMD values at any femur sites. The nulliparae patients in the 60- to 80-year group exhibited significantly higher trochanter and Ward's BMD values than those of the more-than-five-parity group (P < 0.05), whereas in the one-to-two-parity group, spine BMD values appeared to be significantly higher than those of the more-than-five-parity group (p < 0.05). Significant correlations were found between the number of pregnancies and BMD values for the spine (r = −0.23; P < 0.01), trochanter (r = −0.16; P < 0.01), and Ward's triangle (r = −0.14; P < 0.05), with no significant correlation for femur neck BMD (r = −0.08; P > 0.05) values. In conclusion, the present study suggests that the number of pregnancies has an effect on the BMD values and that this situation shows a variation in different age groups. In addition, our study indicates that there is a significant correlation between the number of pregnancies and the spine, trochanter, and Ward's triangle BMD, but there is no correlation for the femur neck BMD. Received: April 30, 2002 / Accepted: January 16, 2003 RID="*" ID="*" Offprint requests to: A. Gur  相似文献   
998.
 Positron-emission tomography (PET) can provide an in vivo method for evaluating metabolism and physiology in normal and diseased tissues. Clinical trials with [18F]2-deoxy-2-fluoro-d-glucose (FDG), the most commonly used radiolabeled tracer for PET imaging, have demonstrated increased accumulation of FDG in several cancer tissues. In this article, we introduce the basic principles of FDG-PET and review current knowledge about FDG-PET for evaluating musculoskeletal tumors. Recent reports and our own experience suggest that FDG-PET cannot be a screening method for differential diagnosis between benign and malignant musculoskeletal lesions, including many neoplasms originating from different tissues altogether. FDG-PET might not accurately reflect the malignant potential of musculoskeletal tumors, but rather might implicate cellular components included in the lesions. A high accumulation of FDG can be observed in histiocytic, fibroblastic, and some neurogenic lesions, regardless of whether they are benign or malignant. More specific uses of FDG-PET, such as grading, staging, and monitoring of musculoskeletal sarcomas, should be considered for each tumor of a different histologic subtype. Received: October 2, 2001 RID="*"  相似文献   
999.
One hundred sixteen patients who underwent surgery for early gastric cancer (EGC) at Careggi General Hospital in Florence between 1987 and 1992 were studied with regard to clinicopathologic features, incidence, and recurrence of the disease. The overall 5-year cumulative survival rate was 87.5%, and the disease-specific 5-year survival rate was 88.2%. EGC was limited to the mucosa in 43 patients (37%), while it infiltrated the submucosa in 73 others (63%). At the time of surgery, 9.5% of patients were found to have lymph node metastasis, always concomitant with submucosal invasion. There was 1 postoperative death (0.8%); 16 patients (13.7%) died of tumor recurrence, and 20 (17.2%) died of unrelated causes. Analysis of recurrence showed an intestinal histotype in 13 patients (81.2%), submucosal infiltration in 14 patients (87.5%), a Pen-A growth pattern in 8 patients (50%), and lymph node involvement in 3 patients (18.7%). The Cox proportional hazard model indicated that age and depth of wall invasion were statistically significant. The best predictor of survival appears to be the depth of invasion within the gastric wall. The claim by several investigators that prognosis for EGC is also associated with the presence of lymph node involvement is not supported by the present study. The postoperative 5-year survival rate in node-negative patients was 88.8% compared to 81.8% in node-positive patients (p = 0.296).  相似文献   
1000.
Purpose: We investigated the efficiency of distal anastomosis with patch plasty (DAPP), both experimentally and clinically. Methods: In our experimental study, dogs were divided into two groups: a control group in which anastomosis was performed without DAPP (n = 7), and a DAPP group in which DAPP was performed at the distal anastomosis (n = 7). In our clinical study, 169 femoropopliteal bypasses were divided into three groups and analyzed. In one group, the saphenous vein was used (SVG group, n = 65); in one group, an expanded polytetrafluoroethylene (ePTFE) graft was used without DAPP (ePTFE group, n = 64); and in one group, an ePTFE graft was used with DAPP (DAPP group, n = 40). Results: In the experimental study, the ratio between the area of thrombus adherence and the entire area of the intraluminal surface of the graft, defined as the thrombus covering ratio, was 48.9% in the control group and 30.2% in the DAPP group. The ratio in the DAPP group was significantly lower than that in the control group. In the clinical study, although there were no significant differences among the three groups in cumulative patency rates of the femoral above-knee popliteal arterial bypasses, the patency in the DAPP group was excellent. The cumulative patency rates of the femoral below-knee popliteal arterial bypasses in the ePTFE group were significantly lower than those in the other two groups. Conclusion: There results suggest that the addition of DAPP may achieve excellent graft patency. Received: February 14, 2002 /Accepted: November 19, 2002 Reprint requests to: K. Dairaku  相似文献   
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