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The sheep seems to be a promising model of osteoporosis and biomaterial osteointegration in osteopenic bone. The long-term ovariectomized sheep model was used for the biological investigation of bone healing around uncoated and hydroxyapatite (HA)-coated pedicle screws in osteopenic bone. Four sheep were ovariectomized and four sheep were sham-operated. Twenty-four months after surgery, the animals were implanted with uncoated and HA-coated stainless steel screws in the lumbar vertebral pedicles. Four months later, bone-to-implant contact, bone ingrowth, and bone hardness were measured around screws. Uncoated stainless steel presented significantly (p < 0.0005) lower bone-to-implant contact in healthy and osteopenic bone compared with HA-coated stainless steel. HA significantly improved bone ingrowth in healthy bone (p < 0.05) compared with uncoated stainless steel. Osteopenia significantly (p < 0.05) reduced the area of bone ingrowth around the screw threads for both types of implants. In the inner thread area, bone microhardness significantly increased (p < 0.05) in HA-coated surface versus uncoated for healthy and osteopenic bone. HA coating significantly enhances bone-to-implant contact also in osteopenic bone in comparison with uncoated stainless steel surfaces. Bone ingrowth and mineralization are ameliorated by the osteoconductive HA coating. However, osteopenia seems to greatly influence bone ingrowth processes around the implanted screws regardless of the characteristics of the material surface.  相似文献   
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Purpose

To analyze changes in spino-pelvic parameters (SPPs) after surgery of high-grade lumbar isthmic spondylolisthesis (HDIS).

Methods

We analyzed 41 patients affected by HDIS operated upon by attempt of reduction and posterior spinal fusion with pedicle screw systems with or without interbody fusion. Pelvic tilt (PT), lumbar lordosis (LL), pelvic incidence (PI), and sacral slope (SS) were measured, and patients were further divided into balanced and unbalanced pelvis subgroups.

Results

SS passed from 46.8° ± 9.8° preoperatively to 50.1° ± 10.1° (p = 0.02). PT passed from 26.7° ± 6.7° preoperatively to 22.9° ± 7.5° (p = 0.003). Unbalanced patients showed significantly higher PT and lower SS compared to the balanced patients preoperatively, and these corrected after surgery. Patients with instrumentation failure (n = 5) had significant increase in PT values postoperatively (p = 0.018).

Conclusions

We confirmed the positive effect of surgery on the SPPs in patients affected by HDIS, which showed different patterns of corrections with surgery for balanced and unbalanced pelvis patients.

  相似文献   
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Engineered nanomaterials have been extensively applied as active materials for technological applications. Since the impact of these nanomaterials on health and environment remains undefined, research on their possible toxic effects has attracted considerable attention. It is known that in humans, for example, the primary site of gold nanoparticles (AuNps) accumulation is the liver. The latter has motivated research regarding the use of AuNps for cancer therapy, since specific organs can be target upon appropriate functionalization of specific nanoparticles. In this study, we investigate the geno and cytotoxicity of two types of AuNps against human hepatocellular carcinoma cells (HepG2) and peripheral blood mononuclear cells (PBMC) from healthy human volunteers. The cells were incubated in the presence of different concentrations of AuNps capped with either sodium citrate or polyamidoamine dendrimers (PAMAM). Our results suggest that both types of AuNps interact with HepG2 cells and PBMC and may exhibit in vitro geno and cytotoxicity even at very low concentrations. In addition, the PBMC were less sensitive to DNA damage toxicity effects than cancer HepG2 cells upon exposure to AuNps.  相似文献   
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Eight families with two or more first-degree relatives affected with ovarian carcinoma were identified among a series of 138 consecutive ovarian cancer patients. History of breast cancer was reported in six of the eight families. Five of 19 patients with familial cancer developed ovarian cancer as a second primary tumor following breast carcinoma, whereas only 6/130 sporadic cases had a previous history of breast cancer. No significant difference was detected in clinical and pathological features between sporadic and familial cases. However, in three high-risk families ovarian cancer tended to develop at a younger age compared with other familial cases and with sporadic occurrences, and nulliparity was less frequent in the familial group. These observations emphasize the need to take into account multiple factors-in addition to positive family history-for the evaluation of genetic predisposition to ovarian carcinoma.  相似文献   
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Levels of estrogen (ER) and progesterone (PR) receptors were measured in 81 patients with primary cervical cancer. In 10 patients, receptor levels were evaluated before and after a short course of tamoxifen treatment. Fifty-six percent of cervical tumors contained ER, and 58%, PR. Receptor level and expression were not related to any clinical and histological characteristic. Moreover, both survival time and response to neoadjuvant chemotherapy did not correlate with the presence of ER and PR. Tamoxifen treatment did not influence ER and PR levels. Our results suggest that steroid hormone receptors are of little value in the management of cervical cancer, and that in this neoplasia, ER is probably not functional.  相似文献   
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CA 15-3 as a tumor marker in gynecological malignancies   总被引:1,自引:0,他引:1  
Serum levels of CA 15-3 were measured in 778 samples from 270 patients with benign and malignant gynecological conditions. Malignant tumors were present in 180 patients including 58 cases with cancer of the ovary, 47 of the endometrium, 61 of the cervix, and 14 of the vulva. The 90 cases with benign conditions included 24 patients with ovarian tumors, 28 with fibromyomatosis, 18 with endometriosis, and 20 with endometrial hyperplasia. Of 180 cancer patients, CA 15-3 serum levels were elevated (greater than 30 U/ml) in 74 cases (41%) and the frequency of abnormal marker values increased with clinical stage. Of 90 patients with benign conditions, high CA 15-3 levels were found in 5 cases (6%) with benign ovarian tumors. Elevated levels of the marker were most commonly seen in ovarian cancer patients (71%). In endometrial, cervical, and vulvar cancer abnormal CA 15-3 values occurred in 32, 26, and 14%, respectively. In endometrial cancer the percentage of positive marker levels increased with more infiltrating and/or less differentiated tumors. A positive correlation was found between residual tumor after surgery and CA 15-3 levels. Serial measurements in sera of patients who underwent chemotherapy showed a good correlation with response to treatment. CA 15-3 values were correlated with clinical course of disease in 87% of cases.  相似文献   
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Topotecan and gemcitabine in platinum/paclitaxel-resistant ovarian cancer   总被引:3,自引:0,他引:3  
24 patients were enrolled into a phase I-II study conducted to determine the maximum tolerated doses of topotecan-gemcitabine in sequential combination and the response rate in platinum/paclitaxel resistant ovarian cancer patients. A total of 83 courses are evaluable, with a median number of three cycles administered per patients (range 2-7). Topotecan was administered on days 1-5 by 30 min i.v. infusion immediately after gemcitabine given by 30 min i.v. on days 1 and 3; cycles were repeated every 28 days. The starting doses were topotecan 0.7 mg/m(2) and gemcitabine 200 mg/m(2). Following dose levels were 08/400; 0.9/600; 0.9/800 for topotecan and gemcitabine, respectively. The maximum tolerated dose (MTD) was reached at dose level 3, the dose-limiting toxicity being represented by febrile neutropenia and thrombocytopenia. After the MTD was reached, granulocyte-colony-stimulating factor was administered in 27% of cycles. Mild and manageable was non hematological toxicity. All patients are so far evaluable for response. Among them 2 complete responses (8.3%; 95% CI: 2.6-19), 1 partial response (4.2%; 95% CI: 3.8-12), 9 no change (37.5%; 95% CI: 18-56.8) and 12 progressions (50%; 95% CI: 30-70) have been registered. Based on these data, there is no evidence that combining topotecan and gemcitabine is better than using either of the two drugs used separately.  相似文献   
10.
OBJECTIVE: We conducted a case-control study to analyze risk factors for ovarian cancer. METHODS: Cases included 440 women (age range 13-80 years, median 54) with a histologically confirmed diagnosis of epithelial ovarian cancer who were admitted to the Gynecological Oncological Department of Gynecologic Oncology at the Catholic University Hospital in Rome, Italy. Controls were women admitted to the same hospital where cases were identified for acute nongynecological, nonhormonal, and nonneoplastic conditions. A total of 868 control women (age range 19-80 years, median 55) were interviewed. RESULTS: In comparison with ever married women, the multivariate odds ratios (OR) of ovarian cancers was 2.0 (95% confidence interval, CI 1.3-3.2) for never married women. Cases and controls were similar as regards educational status and body mass index. No clear relation emerged between ovarian cancer and age at menarche, menopausal status, and age at menopause. In comparison with nulliparae, the estimated ORs were 0.8, 0.9, and 0.7, respectively, in women reporting one, two, or three births. Women reporting two or more induced abortions were at decreased risk of ovarian cancer (OR 0.5, 95% CI 0.3-1.0). In comparison with women reporting their first birth before 20 years of age, the multivariate ORs were 1.8, 2.0, and 2.8, respectively, for women reporting their first birth at age 20-24, 25-30, and >/=31 (chi(2) trend = 10.1). Breast-feeding for more than 1 year was associated with an OR of 0.5 (95% CI, 0.4-0.8). Forty-two (9.5%) cases and 164 (18.9%) controls reported ever oral contraceptive use: in comparison with never users, the multivariate OR was 0.4 (95% CI 0.3-0.6) for ever users, and the risk decreased with duration of use. The OR for ovarian cancer was 2.9 (95% CI, 1.5-5.8) for women with a family history of the disease. CONCLUSION: This study, conducted on a relatively low-risk population, confirms the role of oral contraceptive on ovarian cancer risk and the direct association with family history of ovarian cancer. It also indicates that a later age at first birth is directly, and induced abortion and breast-feeding are inversely, related to the risk of the disease.  相似文献   
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