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1.
The mechanism by which mechanical strain and estrogen stimulate bone cell proliferation was investigated using monolayer cultures of human osteoblastic TE85 cells and female human primary (first-passage) osteoblasts (fHOBs). Both cell types showed small but statistically significant dose-dependent increases in [3H]thymidine incorporation in response to 17beta-estradiol and to a single 10-minute period of uniaxial cyclic strain (1 Hz). In both cell types, the peak response to 17beta-estradiol occurred at 10(-8) - 10(-7) M and the peak response to strain occurred at 3500 microstrain ((mu)epsilon). Both strain-related and 17beta-estradiol-related increases in [3H]thymidine incorporation were abolished by the estrogen receptor (ER) modulator ICI 182,780 (10-8 M). Tamoxifen (10(-9) - 10(-8) M) increased [3H]thymidine incorporation in both cell types but had no effect on their response to strain. In TE85 cells, tamoxifen reduced the increase in [3H]thymidine incorporation associated with 17beta-estradiol to that of tamoxifen alone but had no such effect in fHOBs. In TE85 cells, strain increased medium concentrations of insulin-like growth factor (IGF) II but not IGF-I, whereas 17beta-estradiol increased medium concentrations of IGF-I but not IGF-II. Neutralizing monoclonal antibody (MNAb) to IGF-I (3 microg/ml) blocked the effects of 17beta-estradiol and exogenous truncated IGF-I (tIGF-I; 50 ng/ml) but not those of strain or tIGF-II (50 ng/ml). Neutralizing antibody to IGF-II (3 microg/ml) blocked the effects of strain and tIGF-II but not those of 17beta-estradiol or tIGF-I. MAb aIR-3 (100 ng/ml) to the IGF-I receptor blocked the effects on [3H]thymidine incorporation of strain, tIGF-II, 17beta-estradiol, and tIGF-I. HOBs and TE85 cells, act similarly to rat primary osteoblasts and ROS 17/2.8 cells in their dose-related proliferative responses to strain and 17beta-estradiol, both of which can be blocked by the ER modulator ICI 182,780. In TE85 cells (as in rat primaries and ROS 17/2.8 cells), the response to 17beta-estradiol is mediated by IGF-I, and the response to strain is mediated by IGF-II. Human cells differ from rat cells in that tamoxifen does not block their response to strain and reduces the response to 17beta-estradiol in TE85s but not primaries. In both human cell types (unlike rat cells) the effects of strain and IGF-II as well as estradiol and IGF-I can be blocked at the IGF-I receptor.  相似文献   
2.
Perianal mucinous adenocarcinoma is a rare tumour which may be associated with long‐standing chronic perianal sepsis. Early diagnosis is challenging and is based on a high index of clinical suspicion and specific histological features. Definitive treatment is surgical, in the form of an abdomino‐perineal resection. We hereby describe a case of a perianal mucinous adenocarcinoma arising from long‐standing recurrent perianal fistula and complement this with a brief review of the literature pertaining in particular to the management of this condition.  相似文献   
3.
Doppler ultrasound is known as a reliable technique, which demonstrates the flow characteristics and resistance of ophthalmic arteries. In this study, ophthalmic arterial Doppler signals were obtained from 106 subjects, 54 of whom suffered from ocular Behcet disease while the rest were healthy subjects. Multilayer perceptron neural network (MLPNN) employing delta-bar-delta training algorithm was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by least squares (LS) autoregressive (AR) method for determining the MLPNN inputs. The MLPNN was trained with training set, cross validated with cross validation set and tested with testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the MLPNN. The correct classification rate was 96.43% for healthy subjects and 93.75% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the MLPNN employing delta-bar-delta training algorithm was effective to detect the ophthalmic arterial Doppler signals with Behcet disease.  相似文献   
4.
The synthesis of full and semi interpenetrating networks (IPNs) based on poly(dimethy1-siloxane) (PDMS)/polystyrene, PDMS/polybutadiene and PDMS/poly(glycerylpropoxytriacry-late) 1
  • 1 Glycerylpropoxytriacrylate (GFTA):
  • is described. PDMS was used as host polymer in most cases. PDMS networks were prepared with two prepolymers having different number-average molecular weights between junctions, M?c = 15 · l03 and M?c = 75 · l03. Physical properties of IPN samples such as stress-strain behaviour, swelling and glass transition temperature (Tg) were examined. IPNs of both PDMS/polystyrene and PDMS/poly(glycerylpropoxytriacrylate) exhibit superior mechanical and elastomeric properties with respect to pure PDMS network. Most of the IPN systems studied in this work display two Tgs and indicate phase separation.  相似文献   
    5.
    The European Journal of Health Economics - Patient activation comprises the skills, knowledge and motivation necessary for patients’ effective contribution to their care. We adapted and...  相似文献   
    6.
    7.
    In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats.  相似文献   
    8.
    Pain during sexual activity and ejaculation are the unspoken long-term complications of groin hernia repair. Laparoscopic surgical techniques are associated with decreased post-operative pain and earlier return to daily activities, but its effect on these complications is unclear. This study aims to investigate the effect of transabdominal preperitoneal repair (TAPP) on de-novo pain during sexual intercourse and ejaculation and to compare with open repair. For this reason, two groups were determined according to the surgical technique: the Lichtenstein repair and the TAPP groups and a questionnaire was sent to the patients a minimum of 6 months following the surgery. A total of 317 patients included, as 115 in TAPP and 202 in Lichtenstein repair group. No significant difference was observed concerning pre-operative pain during sexual activity and ejaculation in both groups (p = .75, p = .56). Following the surgery, the number of patients experiencing painful sexual activity was significantly higher in the Lichtenstein repair group compared to the TAPP group (19.3% vs. 11.3%, respectively, p = .03). The post-operative painful ejaculation rate was also significantly lower for the TAPP group (p = .04). The lower rates of post-operative dysejaculation and pain during sexual activity can be achieved with the advantage of laparoscopic surgery.  相似文献   
    9.
    10.
    BACKGROUND: Headache Society (IHS) criteria for episodic tension-type headache were included in the present study. Pain characteristics, associated symptoms, and stress-triggering factors were evaluated. Psychiatric and psychosocial evaluations were performed according to DSM-IV criteria. RESULTS: Pain was bilateral in 93.7% of patients and bitemporal in 50% of children. The intensity of pain increased with motion and stress in more than half of the patients, while pain decreased with rest and massage in 43.7% of patients. Ten of the 16 (62.5%) patients were diagnosed as having a psychiatric disorder. The most common stress-triggering factors were difficulty in adaptation at school and relationship problems with family members. All of the children reported 26 stress factors. Of these stress factors, 20 (76.9%) were reported by children diagnosed with psychiatric disorder. CONCLUSION: These results suggest that in children with tension-type headache a thorough psychiatric evaluation should be performed to rule out underlying psychiatric disorders.  相似文献   
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