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91.
Intravenous bisphosphonates are widely used in the management of metastatic bone disease, as well as osteoporosis. Recent published reports have documented a possible link between treatment with intravenous bisphosphonates and osteonecrosis of the jaw. We report a case of osteonecrosis of the jaw in 1 patient with prostate cancer receiving both chemotherapy and intravenous zoledronic acid (Zometa). Bisphosphonates have been demonstrated to alter the normal bone microenvironment and appear to have direct effects on tumors as well. These changes may contribute to the development of osteonecrosis of the jaw, particularly after tooth extractions or other invasive dental procedures.  相似文献   
92.
Surgical treatment is the procedure of choice for morbidly obese patients. Gastric bypass with a long limb Roux-en-Y anastomosis is the "gold standard" technique for these patients. We sought to determine the early and late results of open gastric bypass with resection of the distal excluded stomach in patients with morbid obesity. We included in this prospective study 400 patients who were seen from September 1999 through August 2003 (311 women and 89 men; mean age, 38.5 years). The mean body mass index of the patients was 46 kg/m2. All underwent 95% distal gastrectomy, with resection of the bypassed stomach, leaving a small gastric pouch of 15 to 20 ml. An end-to-side gastrojejunostomy was performed with circular stapler No. 25. The length of the Roux-en-Y loop was 125 to 150 cm. In all patients, a biopsy was taken from the liver and routine cholecystectomy was performed. Follow-up was as long as 36 months. A barium study was performed in all patients at 5 days after surgery. Mortality and postoperative morbidity rates were 0.5% and 4.75%, respectively, mainly due to anastomotic leak in 10 patients (2.5%). Hospital length of stay was 7 days for 95% of the patients. Follow-up data for longer than 12 months were available in 184 patients. There was excess body weight loss of 70% at 24 and 36 months, and there was an inverse correlation among preoperative body mass index and the loss of weight. Anemia was present in 10%, and incisional hernia was present in 10.2%. At 1 year after surgery, the BAROS index demonstrated very good or excellent index in 96.6% of the patients. Gastric bypass with resection of the distal excluded segment has results very similar to those of gastric bypass alone but eliminates the potential risks of gastric bypass such as anastomotic ulcer, gastrogastric fistula, postoperative bleeding due to peptic ulcer and gastritis, and the eventual future development of gastric cancer. It is also possible to perform via laparoscopy, as we started to do recently.  相似文献   
93.
BACKGROUND: Androgen-independent prostate cancer is today an incurable disease, but increased understanding of the mechanisms for the transition into an androgen-independent state may increase the possibilities for more efficient strategies in the future. METHODS: An androgen-independent subline, LNCaP-19, to the androgen-dependent prostate cancer cell line LNCaP was developed in vitro under standard culture conditions. The characteristics of LNCaP-19 regarding androgen responsiveness, PSA, and VEGF secretion was studied in vitro. The growth in vivo and the microvessel density (MVD) of the tumors were studied after inoculation in nude mice. RESULTS: LNCaP-19 grows equally well in dextran-charcoal stripped FBS (DCC-FBS) as in normal FBS, and rapidly gives rise to tumors in both intact and castrated mice, indicating a true androgen-independent growth. The PSA secretion from LNCaP-19 cells was lower than from LNCaP cells, while the VEGF level was comparable to the secretion from LNCaP cells without androgen stimulation. The MVD was increased in the LNCaP-19 tumors, and the vessels also displayed a changed morphology with exclusively small microvessels without lumen. CONCLUSIONS: LNCaP-19 shows characteristics resembling those of androgen-independent prostate cancer. An increased MVD and changed vessel morphology in the tumor, makes it an interesting model system for studies regarding angiogenesis in the context of the acquisition of androgen independence.  相似文献   
94.
95.
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL.  相似文献   
96.
BACKGROUND: Clinical studies suggest low-dose ketamine may have preemptive effects on postoperative pain in adults. The objective of this study was to determine whether intraoperative low-dose S-ketamine reduces postoperative pain and morphine consumption in children undergoing major urological surgery. MATERIALS: Thirty children scheduled for major urological surgery were included in this prospective study. Anesthesia was performed as total intravenous anesthesia (TIVA) with alfentanil and propofol. Fifteen patients additionally received an intravenous bolus of S-ketamine (0.2 mg.kg-1) followed by a continuous infusion of 5 microg.kg-1.min-1, which was stopped immediately after skin closure (Ketamine Group). Another 15 patients received an infusion of saline (Control group). After transfer to the PACU, pain intensity was evaluated using a numeric rating scale (NRS). First patient controlled analgesia (PCA) request, cumulative morphine consumption and pain intensities within the first 72 h were compared. RESULTS: Morphine consumption was not significantly different during the first 72 h (Control: 0.4 mg.kg-1, 0.24-0.51 mg.kg-1, Ketamine: 0.32 mg.kg-1, 0.19-0.61 mg.kg-1; median, 25-75% percentile; n.s.). However, differences were found in pain intensity during the first postoperative hour (Control: 4.0, 3.2-4.6, Ketamine: 2.5, 1.3-3.5; median, 25-75% percentile; P<0.05) and in the time to first PCA use (Control: 37, 28-46 min, Ketamine: 62, 38-68 min; median, 25-75% percentile; P<0.05). CONCLUSIONS: Intraoperative low-dose S-ketamine had no effect on morphine consumption during the first 72 h after surgery. The differences in pain intensity and time to first PCA use probably reflect additional sedation and antinociceptive effects of S-ketamine rather than a true 'prevention' of pain.  相似文献   
97.
AIM: To evaluate the efficacy, tolerability and safety of darifenacin, an M(3) selective receptor antagonist, in the subgroup of older patients from a pooled analysis of three phase III, multicentre, randomized, double-blind clinical trials in patients with overactive bladder (OAB). PATIENTS AND METHODS: 317 patients aged > or =65 years with OAB symptoms (urge incontinence, urgency and frequency) received up to 12 weeks' oral treatment with darifenacin 7.5 mg or 15 mg once daily or matching placebo. Efficacy was evaluated from daily electronic diary records. Safety endpoints included withdrawal rates and treatment-related adverse events. RESULTS: Darifenacin treatment of patients aged > or =65 years was associated with a dose-related, significant improvement of all the major symptoms of OAB. At week 12, the median reduction in incontinence episodes/week was greater with darifenacin 7.5 mg or 15 mg than in the corresponding placebo arms (66.7% vs. 34.8% and 75.9% vs. 44.8%, respectively, both p < 0.001). Both doses were also significantly superior to placebo in improving micturition frequency (both p < 0.001), bladder capacity (volume voided) (darifenacin 7.5 mg, p = 0.018, darifenacin 15 mg, p < 0.001), and the frequency of urgency episodes (both p < 0.001). Darifenacin was well tolerated. The most common treatment-related adverse events were dry mouth (7.5 mg, 20.6%; 15 mg, 30.9%; placebo, 4.5%) and constipation (7.5 mg, 18.6%; 15 mg, 23.6%; placebo, 6.4%), typically mild or moderate. Use of constipation remedies (laxatives, stool softeners or fibre supplements) was low and similar between groups (7.5 mg, 10.3%; 15 mg, 16.4%; placebo, 10.0%). There were few withdrawals due to treatment-related adverse events (7.5 mg, 1.0%; 15 mg, 9.1%; placebo, 2.7%), and no nervous system or cardiovascular safety concerns. CONCLUSIONS: The results demonstrate excellent efficacy, tolerability and safety with darifenacin 7.5 mg and 15 mg once-daily treatment for OAB in older patients.  相似文献   
98.
Cardiovascular disease (CVD) is the leading cause of mortality in women. In fact, CVD is responsible for a third of all deaths of women worldwide and half of all deaths of women over 50 years of age in developing countries. The prevalence of CVD risk factor precursors is increasing in children. Retrospective analyses suggest that there are some clinically relevant differences between women and men in terms of prevalence, presentation, management and outcomes of the disease, but little is known about why CVD affects women and men differently. For instance, women with diabetes have a significantly higher CVD mortality rate than men with diabetes. Similarly, women with atrial fibrillation are at greater risk of stroke than men with atrial fibrillation. Historically, women have been underrepresented in clinical trials. The lack of good trial evidence concerning sex-specific outcomes has led to assumptions about CVD treatment in women, which in turn may have resulted in inadequate diagnoses and suboptimal management, greatly affecting outcomes. This knowledge gap may also explain why cardiovascular health in women is not improving as fast as that of men. Over the last decades, mortality rates in men have steadily declined, while those in women remained stable. It is also becoming increasingly evident that gender differences in cultural, behavioural, psychosocial and socioeconomic status are responsible, to various degrees, for the observed differences between women and men. However, the interaction between sex-and gender-related factors and CVD outcomes in women remains largely unknown.  相似文献   
99.
Nonhealing chronic wounds in the constantly growing elderly population represent a major public health problem with high socioeconomic burden. Yet, the underlying mechanism of age‐related impairment of wound healing remains elusive. Here, we show that the number of dermal cells expressing cyclin‐dependent kinase inhibitor p21 was elevated upon skin injury, particularly in aged population, in both man and mouse. The nuclear expression of p21 in activated wound fibroblasts delayed the onset of the proliferation phase of wound healing in a p53‐independent manner. Further, the local and transient inhibition of p21 expression by in vivo delivered p21‐targeting siRNA ameliorated the delayed wound healing in aged mice. Our results suggest that the increased number of p21+ wound fibroblasts enforces the age‐related compromised healing, and targeting p21 creates potential clinical avenues to promote wound healing in aged population.  相似文献   
100.
In eukaryotic cells the phospholipid phosphatidylserine (PS) is restricted to the inner plasma-membrane leaflet. This lipid asymmetry, which is maintained by the concerted action of phospholipid transport proteins, is mainly lost during apoptosis. Here, we demonstrate that primary human CD8+ cytotoxic T lymphocytes (CTLs) expose PS on T-cell receptor (TCR)-mediated antigen (Ag) recognition. In contrast to PS externalization on apoptotic cells, activation-induced PS exposure is less pronounced and reversible. Fluorescence microscopic analysis revealed that PS is distributed nonhomogenously over the plasma membrane and concentrated in membrane lipid raft domains at the immunologic synapse. By studying the activity of PS transport proteins using a fluorescence-labeled PS analogue, we found that activation of CTLs inhibited the flippase-mediated inward-directed PS transport without affecting the outward transport. Shielding of exposed PS by annexin V protein during Ag recognition diminished cytokine secretion, activation, and cell-to-cell clustering of Ag-specific CTLs. In summary, our data demonstrate for the first time that externalized PS on Ag-stimulated CTLs is linked to T-cell activation and probably involved in cell-to-cell contact formation at the immunologic synapse.  相似文献   
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