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951.
目的 :探讨肺癌组织层黏连蛋白 (LN)及其受体 (LN -R)的表达和肿瘤转移及预后关系。方法 :采用免疫组织化学技术在 4 2例肺癌患者中研究LN和LN -R的表达。结果 :Ⅰ期患者LN(5 8.30 % )表达高于Ⅱ期 (14 .30 % )及Ⅲ~Ⅳ期 (37.5 2 % )患者 ;无淋巴结肺癌转移患者LN表达率 (6 6 .6 6 % )明显高于有淋巴结转移患者 (2 4 .2 0 % )。有淋巴结肺癌转移患者LN -R表达率 (84 .80 % )明显高于无淋巴结转移患者 (2 2 .2 2 % ) ,这些差异均有统计学意义 (P <0 .0 1)。结论 :LN及其受体 (LN -R)表达在肺癌组织的恶性生物学行为相关 ,可能是临床治疗和预后估计的有用指标。  相似文献   
952.
Chronic stress and depression have adverse consequences on many organ systems, including the skeleton, but the mechanisms underlying stress‐induced bone loss remain unclear. Here we demonstrate that neuropeptide Y (NPY), centrally and peripherally, plays a critical role in protecting against stress‐induced bone loss. Mice lacking the anxiolytic factor NPY exhibit more anxious behavior and elevated corticosterone levels. Additionally, following a 6‐week restraint, or cold‐stress protocol, Npy‐null mice exhibit three‐fold greater bone loss compared to wild‐type mice, owing to suppression of osteoblast activity. This stress‐protective NPY pathway acts specifically through Y2 receptors. Centrally, Y2 receptors suppress corticotropin‐releasing factor expression and inhibit activation of noradrenergic neurons in the paraventricular nucleus. In the periphery, they act to control noradrenaline release from sympathetic neurons. Specific deletion of arcuate Y2 receptors recapitulates the Npy‐null stress response, coincident with elevated serum noradrenaline. Importantly, specific reintroduction of NPY solely in noradrenergic neurons of otherwise Npy‐null mice blocks the increase in circulating noradrenaline and the stress‐induced bone loss. Thus, NPY protects against excessive stress‐induced bone loss, through Y2 receptor‐mediated modulation of central and peripheral noradrenergic neurons. © 2014 American Society for Bone and Mineral Research.  相似文献   
953.
In humans, aging and glucocorticoid treatment are associated with reduced bone mass and increased marrow adiposity, suggesting that the differentiation of osteoblasts and adipocytes may be coordinately regulated. Within the bone marrow, both osteoblasts and adipocytes are derived from mesenchymal progenitor cells, but the mechanisms guiding the commitment of mesenchymal progenitors into osteoblast versus adipocyte lineages are not fully defined. The heterotrimeric G protein subunit Gsα activates protein kinase A signaling downstream of several G protein‐coupled receptors including the parathyroid hormone receptor, and plays a crucial role in regulating bone mass. Here, we show that targeted ablation of Gsα in early osteoblast precursors, but not in differentiated osteocytes, results in a dramatic increase in bone marrow adipocytes. Mutant mice have reduced numbers of mesenchymal progenitors overall, with an increase in the proportion of progenitors committed to the adipocyte lineage. Furthermore, cells committed to the osteoblast lineage retain adipogenic potential both in vitro and in vivo. These findings have clinical implications for developing therapeutic approaches to direct the commitment of mesenchymal progenitors into the osteoblast lineage. © 2014 American Society for Bone and Mineral Research  相似文献   
954.
Treatment with the cathepsin K (CatK) inhibitor odanacatib (ODN) protects against bone loss and maintains normal biomechanical properties in the spine and hip of ovariectomized (OVX) preclinical models. Here, we characterized the effects of ODN on the dynamics of cortical modeling and remodeling, and dimension and strength of the central femur in adult OVX‐rhesus monkeys. Animals were treated with vehicle or ODN (6 or 30 mg/kg, once per day [q.d., p.o.]) in prevention mode for 21 months. Calcein and tetracycline double‐labeling were given at 12 and 21 months, and the femoral cross‐sections were subjected to dynamic histomorphometric and cement line analyses. ODN treatment significantly increased periosteal and endocortical bone formation (BFR/BS), accompanied with an increase in endocortical mineralizing surface (102%, p < 0.01) with the 6 mg/kg dose. ODN at both doses reduced remodeling hemiosteon numbers by 51% and 66% (p < 0.05), respectively, and ODN 30 mg/kg numerically reduced activation frequency without affecting wall thickness. On the same endocortical surface, ODN increased all modeling‐based parameters, while reducing intracortical remodeling, consistent with the observed no treatment effects on cortical porosity. ODN 30 mg/kg markedly increased cortical thickness (CtTh, p < 0.001) and reduced marrow area (p < 0.01). Lastly, ODN treatment increased femoral structural strength (p < 0.001). Peak load was positively correlated with the increases in bone mineral content (BMC) (r2 = 0.9057, p < 0.0001) and CtTh (r2 = 0.6866, p < 0.0001). Taken together, by reducing cortical remodeling‐based and stimulating modeling‐based bone formation, ODN significantly improved cortical dimension and strength in OVX monkeys. This novel mechanism of CatK inhibition in stimulating cortical formation suggests that ODN represents a novel therapeutic approach for the treatment of osteoporosis. © 2014 American Society for Bone and Mineral Research.  相似文献   
955.
In a 53-year-old woman, Sagliker syndrome developed during 22 years of treatment with intermittent hemodialysis as a result of severe secondary hyperparathyroidism (SHPT) complicating end-stage renal disease. She failed medical managements and lost her renal graft just after the kidney transplantation due to acute rejection. Although surgical parathyroidectomy was effective, the parathyroid hormone level became extremely high again due to recurrent hyperparathyroidism. It is possible that such patient could survive long-term with dialysis, but prevention of severe SHPT is the most important.  相似文献   
956.
957.
There are contradictory results about the effect of angiotensin-converting enzyme inhibitors (ACEIs) on bone. This study was performed to address the skeletal renin?angiotensin system (RAS) activity and the effects of the ACEI, captopril, on the bone of streptozotocin-induced type 1 diabetic mice. Histochemical assessment on bone paraffin sections was conducted by Safranin O staining and tartrate-resistant acid phosphatase staining. Micro-computed tomography was performed to analyze bone biological parameters. Gene and protein expression were determined by real-time polymerase chain reaction and immunoblotting, respectively. Type 1 diabetic mice displayed osteopenia phenotype and captopril treatment showed no osteoprotective effects in diabetic mice as shown by the reduction of bone mineral density, trabecular thickness and bone volume/total volume. The mRNA expression of ACE and renin receptor, and the protein expression of renin and angiotensin II were markedly up-regulated in the bone of vehicle-treated diabetic mice compared to those of non-diabetic mice, and these molecular changes of skeletal RAS components were effectively inhibited by treatment with captopril. However, treatment with captopril significantly elevated serum tartrate-resistant acid phosphatase 5b levels, reduced the ratio of osteoprotegerin/receptor activator of nuclear factor-κB ligand expression, increased carbonic anhydrase II mRNA expression and the number of matured osteoclasts and decreased transforming growth factor-β and osteocalcin mRNA expression in the tibia compared to those of diabetic mice. The present study demonstrated that the use of the ACEI, captopril, has no beneficial effect on the skeletal biological properties of diabetic mice. However, this could be attributed, at least partially, to its suppression of osteogenesis and stimulation of osteoclastogenesis, even though it could effectively inhibit high activity of local RAS in the bone of diabetic mice.  相似文献   
958.

Background

Cholecystolithiasis is the most common disease treated by general surgery, with an incidence of about 0.15–0.22 %. The most common therapies are open cholecystectomy (OC) or laparoscopic cholecystectomy (LC). However, with a greater understanding of the function of the cholecyst, more and more patients and surgeons are aware that preserving the functional cholecyst is important for young patients, as well as patients who would not tolerate anesthesia associated with either OC or LC. Based on these considerations, we have introduced a notable, minimally invasive treatment for cholecystolithotomy.

Methods

We performed a retrospective review of patients with cholecystolithiasis who were unable to tolerate surgery or who insisted on preserving the functional cholecyst. Our particular approach can be simply described as ultrasound-guided percutaneous cholecystostomy combined with a choledochoscope for performing a cholecystolithotomy under local anesthesia.

Results

Ten patients with cholecystolithiasis were treated via this approach. All except one patient had their gallbladder stones totally removed under local anesthesia, without the aggressive procedures associated with OC or LC. The maximum number of gallbladder stones removed was 16, and the maximum diameter was 13 mm without lithotripsy. After the minimally invasive surgery, the cholecyst contractile functions of all patients were normal, confirmed via ultrasound after a high-fat diet. Complications such as bile duct injury, biliary fistula, and bleeding occurred significantly less often than with OC and LC. The recurrence rates for each of 2 post-operative years were about 11.11 % (1/9, excluding a failure case) with uncertainty surrounding recurrence or residue, and 22.22 % (2/9, including one non-recurrence patient with follow-up time of 22 months), respectively.

Conclusions

Ultrasound-guided percutaneous cholecystostomy combined with choledochoscope is a safe, efficient, and minimally invasive cholecystolithotomy method. We recommend this technique for the management of small stones (less than 15 mm) in high-risk surgical patients.  相似文献   
959.
960.
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