In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are e...In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.展开更多
China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable prod...China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes.展开更多
With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes ...With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes the connotation of teacher data literacy, and then combs through the status quo and dilemmas of teachers’ data literacy ability in applied universities. The paper proposes to enhance the data literacy ability of teachers from the perspective of organizational learning. Through building a digital culture, building a data-driven teaching environment, and constructing an interdisciplinary learning community to further promote the application of the theory and practice of datafication inside and outside the organization, and ultimately improve the quality of teaching.展开更多
Background: In low-income African countries, the demand and use of plastic surgery operations including abdominoplasty, liposuction and Brazilian butt lift (BBL) are increasing. The goal of this work is to present my ...Background: In low-income African countries, the demand and use of plastic surgery operations including abdominoplasty, liposuction and Brazilian butt lift (BBL) are increasing. The goal of this work is to present my experience and the challenges of this aesthetic plastic surgery among black African women. Material and Methods: A retrospective study was conducted about the abdominoplasties, liposuctions and Brazilian butt lift (BBL) which I operated in public and private hospitals at Kinshasa (Democratic Republic of Congo) in black African women. It covers a period of 13 years, going from December 1, 2010 to December 1, 2023. For this study, I had at least 6 months period (to Juin 1, 2024) to assess the occurrence of early and late postoperative complications. Results: I performed 84 abdominoplasties, 144 liposuctions and 23 Brazilian butt lifts (BBL). The average age at the time of abdominoplasty was 44 years with extremes ranging from 26 to 55 years and a concentration of cases (60.7%) in the age group of 40 to 49 years. The age group of 20 to 29 years old represented the lowest rate of requests for abdominoplasty (4.7%). Patients with a BMI of 30 to 2 were the majority (61.9%), followed by those between 25 to 2 (29.7%). 67.8% of patients were obese (BMI ≥ 30 kg/m2). The average age at the time of liposuction was 41 years with extremes ranging from 21 years to 69 years;and more than half of cases (68%) in the age group between 30 and 49 years. As for Brazilian butt lift (BBL), the average age was 33 years with extremes ranging from 24 to 42 years and a concentration of patients (91.3%) between 20 and 39 years. The immediate postoperative complications of abdominoplasties observed were: seroma in 7% of cases, hematoma and partial infection of the surgical site in 5% of cases. Pathological scars (hypertrophic, keloid) after abdominoplasties were observed in 9% of cases. The most common complication of liposuction was contour deformity. I observed 16 patients (11.1%) with soft-tissue depressions or elevations, skin panniculus or folds. For Brazalian Butt Lift (BBL), complications like asymmetry for 2 patients (8.9%), contour irregularities for 2 patients (8.9%), and excessive fat removal for 6 patients (26%), had observed. I have not recorded any cases of death or pulmonary embolism. Conclusion: I perform aesthetic plastic surgery procedures in black African women with a high socioeconomic standard of living compared to the average of the general population. The renunciation of planned surgery is motivated by the impossibility of paying the cost of the operation as well as by popular and religious perceptions regarding cosmetic surgery. The results of these aesthetic plastic surgery procedures carried out are very satisfactory for them. The challenges to overcome are mainly threefold: the unforeseeable complications of these cosmetic plastic surgery procedures, popular and religious perceptions of cosmetic surgery as well as the poverty of the population.展开更多
Aim: To investigate how erectile dysfunction (ED) medications affect morning erection in patients with ED and how they respond to the return of morning erection. Methods: This study was conducted in 120 patients w...Aim: To investigate how erectile dysfunction (ED) medications affect morning erection in patients with ED and how they respond to the return of morning erection. Methods: This study was conducted in 120 patients who experienced successful intercourse with either tadalafil or sildenafil. Using a random face-to-face interview and a questionnaire (about the quality and number of days getting morning erection after using the two medications), the impact of the medications on the morning erections was investigated, and the participants were asked about their feelings on regaining morning erection. Results: Of the respondents, 81% (68% of those with sildenafil and 99% of those with tadalafil) experienced morning erections after taking an oral ED medication. The men who took tadalafil mainly for 2 days with one dose, while those who took sildenafil experienced morning erections mainly for 1 day. The major sentiment upon regaining a morning erection was, "having more confidence as a man" (74%). Among the 96 respondents who experienced morning erections with tadalafil, 52% preferred tadalafil over sildenafil, not only because of freedom from concerns about a specific time to have relations, but also regaining morning erection. Conclusion: Regaining a morning erection affects the recovery of confidence as a man and influences the preference for tadalafil over sildenafil.展开更多
Erectile response is centrally and peripherally regulated by androgens. The original insights into the mechanisms of action of androgens were that androgens particularly exert effects on libido and that erections in r...Erectile response is centrally and peripherally regulated by androgens. The original insights into the mechanisms of action of androgens were that androgens particularly exert effects on libido and that erections in response to erotic stimuli were relatively androgen-independent. It was shown that sexual functions in men required androgen levels at the low end of reference values of testosterone. So it seemed that testosterone was not useful treatment for men with erectile difficulties, particularly following the advent of the phosphodiesterase type 5 (PDE5) inhibitors. However, approximately 50% of those treated with PDE5 inhibitors discontinue their treatment. A number of recent developments shed new light on testosterone treatment of erectile dysfunction (ED) in aging men. (1) A recent insight is that, in contrast to younger men, elderly men might require higher levels of testosterone for normal sexual functioning. (2) Several studies have indicated that PDE5 inhibitors are not always sufficient to restore erectile potency in men, and that testosterone improves the therapeutical response to PDE5 inhibitors considerably. (3) There is growing insight that testosterone has profound effects on tissues of the penis involved in the mechanism of erection and that testosterone deficiency impairs the anatomical and physiological substrate of erectile capacity, reversible upon androgen replacement. The synthesis of PDE5 is upregulated by androgens, and the arterial inflow into the penis is improved by giving androgen. The above invites a re-examination of the merits of giving testosterone to aging men with ED. The beneficial effects of PDE5 inhibitors may only be optimally expressed in a eugonadal environment. (Asian J Androl 2006 Jan; 8: 3-9)展开更多
Aim: To determine if androgens directly regulate veno-occlusion or if androgens act indirectly to maintain the penilestructures which control outflow. Methods: Using CASTRATE and TESTO rats, measurement was made of me...Aim: To determine if androgens directly regulate veno-occlusion or if androgens act indirectly to maintain the penilestructures which control outflow. Methods: Using CASTRATE and TESTO rats, measurement was made of meanarterial pressure (MAP), intracavernosal pressure (CCP), and intracavernosal flow (CCF) during erection resultingfrom stimulation of the autonomic innervation of the penis. CCP and CCF were also measured during saline infusioninto the cavernosal sinuses before and after treatment with sodium nitroprusside (SNP, a nitric oxide donor drag) tofully relax cavernosal smooth muscle. Penile tissue was also collected to measure the content of α actin and proline andhydroxyproline to determine if brief withdrawal of androgenic support led to changes in the number of smooth musclecells or the collagen content of the tissue. Results: Infusion of saline into the cavernosal sinuses demonstrated thatveno-occlusion was defective in CASTRATE rats while reno-occlusion was fully functional in TESTO animals.Furthermore, veno-occlusion could be induced in CASTRATE rats if they were first treated with SNP. Thisobservation suggests that failure of veno-occlusion in the CASTRATE rats is due to a deficiency in the production of NOresulting in a reduction in the degree of relaxation of the penile smooth muscle. The measurements of smooth muscleα actin and proline and hydroxyproline content of collagen showed that both were unaffected by castration and that thebasic structure of the penis did not degenerate after one week without androgenic support. Conclusion: Theseresults can be interpreted to mean that androgens control the veno-occlusive mechanism indirectly via a NO dependentmechanism and not by maintaining the structures of the penis which are essential to reno-occlusion.展开更多
Introduction: Erectile episodes occurring in the night time are considered normal and are usually related to the REM sleep. Spontaneous painful erections are unusual but they can have a great impact in the patient’s ...Introduction: Erectile episodes occurring in the night time are considered normal and are usually related to the REM sleep. Spontaneous painful erections are unusual but they can have a great impact in the patient’s quality of sleep and, for consequence, quality of life. Report: We present a patient who has been presenting painful erections which wake him up almost every night. We discuss the workup and treatment offered to the patient, as well as the short-time response and two months follow-up. Discussion: Although studies still do not explain this relationship, nocturnal erections occur only during rapid eye movement (REM) sleep, which can be confirmed by polysomnography accompanied by Nocturnal Penile Tumescence testing or RigiScan test. However, diagnosis can be established based exclusively on clinical aspects. Based on all literature reviewed, the initial treatment should safely consist in improvement in sleep architecture and pelvis muscles relaxation. Conclusion: After the first suspicion, polysomnography with rigidity measurements of nocturnal erections should be considered although clinical diagnosis and therapeutic test may be acceptable. The management we suggest is usually effective, well tolerated and sustained.展开更多
Aim: To determine the effect of sildenafil citrate on the nocturnal penile erections (i.e. time to onset, the duration of erection, and the interval between first and second erections) of healthy young men. Methods...Aim: To determine the effect of sildenafil citrate on the nocturnal penile erections (i.e. time to onset, the duration of erection, and the interval between first and second erections) of healthy young men. Methods: Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device (Dacomed, Minneapolis, USA). After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data. Results: The mean time to onset of the first erection with sildenafil citrate was (34 ± 18) min, whereas it was (74 ± 24) min (P 〈 0.001) without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6 ± 0.5 in contrast to 2.4 ± 0.5 with no medica- tion (P = 0.001). The interval between first and second erections was shorter with sildenafil citrate: (52 ± 26) min vs. (85 ± 34) min (P = 0.01). The duration of the last erection was statistically significantly longer with the sildenafil citrate: (64 ± 33) min vs. (42 ± 28) min (P 〈 0.01). Conclusion: Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.展开更多
Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile...Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. Results: The diameter of penis and the ICP were significantly increased and the corpus cavernosal EMG significantly reduced in the sildenafil group. Conclusion: Sildenafil citrate increases the penile size and ICP and reduces the corpus cavernosal EMG in male rhesus macaque.展开更多
The extreme large miter gates of TGP permanent shiplock are of great difficulty in erection,in view of the stringent requirement of precision control and the complicated components.The major erection problems,such as ...The extreme large miter gates of TGP permanent shiplock are of great difficulty in erection,in view of the stringent requirement of precision control and the complicated components.The major erection problems,such as the erection measurement control, the selection of erection position of gate leaf,welding and deformation manipulation,the erection of back tie rods,the installation of apex pintle and prestressing anchorages,etc., had been carefully deliberated, and the optimized approaches were adopted.The erection practice of the miter gate at No.1 lock head shows that the adopted erection technology is safe,reliable and effective, and it may be used for reference for similar miter gates.展开更多
Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to ...Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to analyze two segment ring models under uniform injected pressure: (1) segment ring without wedge-shaped segment, which has 16 types of preinstall erection tolerance; (2) segment ring with wedge-shaped segment, which has no preinstall erection tolerance. The analysis results indicate that different erection tolerances can cause irregular deformation in segment ring under uniform injected pressure, and that the tolerance values are enlarged further. Wedge-shaped segment apparently affects the overall deformation of segment ring without erection tolerances. The uniform injected pressure can cause deformation of ring with wedge-shaped segment irregular, and dislocations also appear in this situation. The stress of segment with erection tolerances is much larger than that of segment without erection tolerances. Enlarging the central angle of wedge-shaped segment can make the irregular deformation and dis- locations of segments smaller. The analysis results also provide basis for erection tolerance control and improvement of segment constitution.展开更多
In contrast to the spinal control of erection, relatively little is known about the brain control. In the present review, we have outlined the role of brain structures involved in penile erection and provided a synops...In contrast to the spinal control of erection, relatively little is known about the brain control. In the present review, we have outlined the role of brain structures involved in penile erection and provided a synopsis on the brain circuit of erection. Findings from both animal and human studies are discussed. Evidence suggests that the most important structures are the frontal lobe, cingulate gyrus, amygdala, thalamus and hypothalamus. Within the brain circuit of erection, the thalamus serves as a gate-controller in which all relevant information is evaluated and further processed to higher and lower centres.展开更多
In this work, the aerodynamic stability of the Yichang Suspension Bridge over Yangtze River during erection was determined by three-dimensional nonlinear flutter analysis, in which the nonlinearities of structural dyn...In this work, the aerodynamic stability of the Yichang Suspension Bridge over Yangtze River during erection was determined by three-dimensional nonlinear flutter analysis, in which the nonlinearities of structural dynamic characteristics and aeroelastic forces caused by large deformation are fully considered. An interesting resuh obtained was that the bridge was more stable when the stiffening girders were erected in a non-symmetrical manner as opposed to the traditional symmetrical erection schedule. It was also found that the severe decrease in the aerodynamic stability was due to the nonlinear effects. Therefore, the nonlinear factors should be considered accurately in aerodynamic stability analysis of long-span suspension bridges during erection.展开更多
Aim: Epididymal proteins are known to play an important role in the maturation of spermatozoa, we ought to deter-mine if there are regional differences in androgen-dependent epididymal proteins. Methods: A group of ad...Aim: Epididymal proteins are known to play an important role in the maturation of spermatozoa, we ought to deter-mine if there are regional differences in androgen-dependent epididymal proteins. Methods: A group of adult rats wascastrated and epididymides were removed three days following castration. The epididymides were dissected into caput,corpus and cauda segments, homogenized, and proteins were fractionated by anion exchange HPLC. Proteins in select-ed fractions were resolved by SDS-PAGE and visualized by silver staining. Results: It was observed that the levels ofmultiple proteins drastically reduced in the various regions of epididymis of the orchiectomized rats. Conclusion: Theepididymal proteins appear to be useful markers to study androgenic action in the epididymis.展开更多
Aim: To investigate a possible potentiation effect of apomorphine (APO) on sildenafil-induced penile erection in the conscious rabbit. Methods: Erection of male New Zealand White rabbits (3.5-4.0 kg, n=12) was assesse...Aim: To investigate a possible potentiation effect of apomorphine (APO) on sildenafil-induced penile erection in the conscious rabbit. Methods: Erection of male New Zealand White rabbits (3.5-4.0 kg, n=12) was assessed by measuring the length of the uncovered penile mucosa and the duration of erection before and after intravenous administration of agents. After injection of APO (0, 0.05, 0.1 and 0.4 mg/kg), sildenafil was administered intravenously in a dose-response manner (0.5, 1 and 5 mg/kg). In additional experiments, the effect of increasing doses of sildenafil in combination with APO on systemic blood pressure was evaluated. Results: Systemic administration of sildenafil induced a dose-dependent increase in the penile length. Intravenous injection of APO alone did not produce any change in the penile length, while significantly enhanced the penile erection induced by sildenafil. The co-administration of 0.1 mg/kg of APO and 1 mg/kg of sildenafil was found to be the most effective combination in producing penile erection. Intravenous administration of sildenafil caused a concentration-dependent decrease in systemic blood pressure, but no additional decrease was observed with co-administration of APO. Conclusion: APO enhances the penile erection induced by sildenafil in the conscious rabbit without causing an additional decrease in blood pressure.展开更多
基金Ho Chi Minh City University of Technology(HCMUT)Vietnam National University Ho Chi Minh City(VNU-HCM)for supporting this study。
文摘In this paper,two lifting mechanism models with opposing placements,which use the same hydraulic hoist model and have the same angle of 50°,have been developed.The mechanical and hydraulic simulation models are established using MATLAB Simscape to analyze their kinetics and dynamics in the lifting and holding stages.The simulation findings are compared to the analytical calculation results in the steady state,and both methods show good agreement.In the early lifting stage,Model 1 produces greater force and discharges goods in the container faster than Model 2.Meanwhile,Model 2 reaches a higher force and ejects goods from the container cleaner than its counterpart at the end lifting stage.The established simulation models can consider the effects of dynamic loads due to inertial moments and forces generated during the system operation.It is crucial in studying,designing,and optimizing the structure of hydraulic-mechanical systems.
基金the Fundamental Research Funds for the Central Universities of China(No.20CX02308A)CNOOC Project(No.ZX2022ZCCYF3835).
文摘China’s unconventional gas fields have a large number of low-productivity and low-efficiency wells, many of whichare located in remote and environmentally harsh mountainous areas. To address the long-term stable productionof these gas wells, plunger-lift technology plays an important role. In order to fully understand and accurately graspthe drainage and gas production mechanisms of plunger-lift, a mechanical model of plunger-liquid column uplift inthe plunger-lift process was established, focusing on conventional plunger-lift systems and representative wellboreconfigurations in the Linxing region. The operating casing pressure of the plunger-lift process and the calculationmethod for the maximum daily fluid production rate based on the work regime with the highest fluid recovery ratewere determined. For the first time, the critical flow rate method was proposed as a constraint for the maximumliquid-carrying capacity of the plunger-lift, and liquid-carrying capacity charts for conventional plunger-lift withdifferent casing sizes were developed. The results showed that for 23/8 casing plunger-lift, with a well depth ofshallower than 808 m, the maximum drainage rate was 33 m3/d;for 27/8 casing plunger-lift, with a well depth ofshallower than 742 m, the maximum drainage rate was 50.15 m3/d;for 31/2 casing plunger-lift, with a well depthof shallower than 560 m, the maximum drainage rate was 75.14 m3/d. This research provides a foundation for thescientific selection of plunger-lift technology and serves as a decision-making reference for developing reasonableplunger-lift work regimes.
文摘With the arrival of the big data era, the modern higher education model has undergone radical changes, and higher requirements have been put forward for the data literacy of college teachers. The paper first analyzes the connotation of teacher data literacy, and then combs through the status quo and dilemmas of teachers’ data literacy ability in applied universities. The paper proposes to enhance the data literacy ability of teachers from the perspective of organizational learning. Through building a digital culture, building a data-driven teaching environment, and constructing an interdisciplinary learning community to further promote the application of the theory and practice of datafication inside and outside the organization, and ultimately improve the quality of teaching.
文摘Background: In low-income African countries, the demand and use of plastic surgery operations including abdominoplasty, liposuction and Brazilian butt lift (BBL) are increasing. The goal of this work is to present my experience and the challenges of this aesthetic plastic surgery among black African women. Material and Methods: A retrospective study was conducted about the abdominoplasties, liposuctions and Brazilian butt lift (BBL) which I operated in public and private hospitals at Kinshasa (Democratic Republic of Congo) in black African women. It covers a period of 13 years, going from December 1, 2010 to December 1, 2023. For this study, I had at least 6 months period (to Juin 1, 2024) to assess the occurrence of early and late postoperative complications. Results: I performed 84 abdominoplasties, 144 liposuctions and 23 Brazilian butt lifts (BBL). The average age at the time of abdominoplasty was 44 years with extremes ranging from 26 to 55 years and a concentration of cases (60.7%) in the age group of 40 to 49 years. The age group of 20 to 29 years old represented the lowest rate of requests for abdominoplasty (4.7%). Patients with a BMI of 30 to 2 were the majority (61.9%), followed by those between 25 to 2 (29.7%). 67.8% of patients were obese (BMI ≥ 30 kg/m2). The average age at the time of liposuction was 41 years with extremes ranging from 21 years to 69 years;and more than half of cases (68%) in the age group between 30 and 49 years. As for Brazilian butt lift (BBL), the average age was 33 years with extremes ranging from 24 to 42 years and a concentration of patients (91.3%) between 20 and 39 years. The immediate postoperative complications of abdominoplasties observed were: seroma in 7% of cases, hematoma and partial infection of the surgical site in 5% of cases. Pathological scars (hypertrophic, keloid) after abdominoplasties were observed in 9% of cases. The most common complication of liposuction was contour deformity. I observed 16 patients (11.1%) with soft-tissue depressions or elevations, skin panniculus or folds. For Brazalian Butt Lift (BBL), complications like asymmetry for 2 patients (8.9%), contour irregularities for 2 patients (8.9%), and excessive fat removal for 6 patients (26%), had observed. I have not recorded any cases of death or pulmonary embolism. Conclusion: I perform aesthetic plastic surgery procedures in black African women with a high socioeconomic standard of living compared to the average of the general population. The renunciation of planned surgery is motivated by the impossibility of paying the cost of the operation as well as by popular and religious perceptions regarding cosmetic surgery. The results of these aesthetic plastic surgery procedures carried out are very satisfactory for them. The challenges to overcome are mainly threefold: the unforeseeable complications of these cosmetic plastic surgery procedures, popular and religious perceptions of cosmetic surgery as well as the poverty of the population.
文摘Aim: To investigate how erectile dysfunction (ED) medications affect morning erection in patients with ED and how they respond to the return of morning erection. Methods: This study was conducted in 120 patients who experienced successful intercourse with either tadalafil or sildenafil. Using a random face-to-face interview and a questionnaire (about the quality and number of days getting morning erection after using the two medications), the impact of the medications on the morning erections was investigated, and the participants were asked about their feelings on regaining morning erection. Results: Of the respondents, 81% (68% of those with sildenafil and 99% of those with tadalafil) experienced morning erections after taking an oral ED medication. The men who took tadalafil mainly for 2 days with one dose, while those who took sildenafil experienced morning erections mainly for 1 day. The major sentiment upon regaining a morning erection was, "having more confidence as a man" (74%). Among the 96 respondents who experienced morning erections with tadalafil, 52% preferred tadalafil over sildenafil, not only because of freedom from concerns about a specific time to have relations, but also regaining morning erection. Conclusion: Regaining a morning erection affects the recovery of confidence as a man and influences the preference for tadalafil over sildenafil.
文摘Erectile response is centrally and peripherally regulated by androgens. The original insights into the mechanisms of action of androgens were that androgens particularly exert effects on libido and that erections in response to erotic stimuli were relatively androgen-independent. It was shown that sexual functions in men required androgen levels at the low end of reference values of testosterone. So it seemed that testosterone was not useful treatment for men with erectile difficulties, particularly following the advent of the phosphodiesterase type 5 (PDE5) inhibitors. However, approximately 50% of those treated with PDE5 inhibitors discontinue their treatment. A number of recent developments shed new light on testosterone treatment of erectile dysfunction (ED) in aging men. (1) A recent insight is that, in contrast to younger men, elderly men might require higher levels of testosterone for normal sexual functioning. (2) Several studies have indicated that PDE5 inhibitors are not always sufficient to restore erectile potency in men, and that testosterone improves the therapeutical response to PDE5 inhibitors considerably. (3) There is growing insight that testosterone has profound effects on tissues of the penis involved in the mechanism of erection and that testosterone deficiency impairs the anatomical and physiological substrate of erectile capacity, reversible upon androgen replacement. The synthesis of PDE5 is upregulated by androgens, and the arterial inflow into the penis is improved by giving androgen. The above invites a re-examination of the merits of giving testosterone to aging men with ED. The beneficial effects of PDE5 inhibitors may only be optimally expressed in a eugonadal environment. (Asian J Androl 2006 Jan; 8: 3-9)
文摘Aim: To determine if androgens directly regulate veno-occlusion or if androgens act indirectly to maintain the penilestructures which control outflow. Methods: Using CASTRATE and TESTO rats, measurement was made of meanarterial pressure (MAP), intracavernosal pressure (CCP), and intracavernosal flow (CCF) during erection resultingfrom stimulation of the autonomic innervation of the penis. CCP and CCF were also measured during saline infusioninto the cavernosal sinuses before and after treatment with sodium nitroprusside (SNP, a nitric oxide donor drag) tofully relax cavernosal smooth muscle. Penile tissue was also collected to measure the content of α actin and proline andhydroxyproline to determine if brief withdrawal of androgenic support led to changes in the number of smooth musclecells or the collagen content of the tissue. Results: Infusion of saline into the cavernosal sinuses demonstrated thatveno-occlusion was defective in CASTRATE rats while reno-occlusion was fully functional in TESTO animals.Furthermore, veno-occlusion could be induced in CASTRATE rats if they were first treated with SNP. Thisobservation suggests that failure of veno-occlusion in the CASTRATE rats is due to a deficiency in the production of NOresulting in a reduction in the degree of relaxation of the penile smooth muscle. The measurements of smooth muscleα actin and proline and hydroxyproline content of collagen showed that both were unaffected by castration and that thebasic structure of the penis did not degenerate after one week without androgenic support. Conclusion: Theseresults can be interpreted to mean that androgens control the veno-occlusive mechanism indirectly via a NO dependentmechanism and not by maintaining the structures of the penis which are essential to reno-occlusion.
文摘Introduction: Erectile episodes occurring in the night time are considered normal and are usually related to the REM sleep. Spontaneous painful erections are unusual but they can have a great impact in the patient’s quality of sleep and, for consequence, quality of life. Report: We present a patient who has been presenting painful erections which wake him up almost every night. We discuss the workup and treatment offered to the patient, as well as the short-time response and two months follow-up. Discussion: Although studies still do not explain this relationship, nocturnal erections occur only during rapid eye movement (REM) sleep, which can be confirmed by polysomnography accompanied by Nocturnal Penile Tumescence testing or RigiScan test. However, diagnosis can be established based exclusively on clinical aspects. Based on all literature reviewed, the initial treatment should safely consist in improvement in sleep architecture and pelvis muscles relaxation. Conclusion: After the first suspicion, polysomnography with rigidity measurements of nocturnal erections should be considered although clinical diagnosis and therapeutic test may be acceptable. The management we suggest is usually effective, well tolerated and sustained.
文摘Aim: To determine the effect of sildenafil citrate on the nocturnal penile erections (i.e. time to onset, the duration of erection, and the interval between first and second erections) of healthy young men. Methods: Twenty-two potent men, 23-29 years old, were recruited for the study. All subjects completed three sessions over consecutive nights using the RigiScan monitoring device (Dacomed, Minneapolis, USA). After a first night of adaptation, night 2 records were their baseline values, and on night 3 they received 100 mg of sildenafil citrate. Statistical comparisons were done between the second and third night data. Results: The mean time to onset of the first erection with sildenafil citrate was (34 ± 18) min, whereas it was (74 ± 24) min (P 〈 0.001) without sildenafil citrate. The number of erections observed during the first 5 h after sildenafil citrate medication was 3.6 ± 0.5 in contrast to 2.4 ± 0.5 with no medica- tion (P = 0.001). The interval between first and second erections was shorter with sildenafil citrate: (52 ± 26) min vs. (85 ± 34) min (P = 0.01). The duration of the last erection was statistically significantly longer with the sildenafil citrate: (64 ± 33) min vs. (42 ± 28) min (P 〈 0.01). Conclusion: Healthy young men achieved erection within 34 min after sildenafil citrate administration, which is shorter than the 1 h interval proposed by the manufacturer. The interval between the first and second erections was shorter and the duration of the last nocturnal erection was longer.
文摘Aim: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. Methods: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. Results: The diameter of penis and the ICP were significantly increased and the corpus cavernosal EMG significantly reduced in the sildenafil group. Conclusion: Sildenafil citrate increases the penile size and ICP and reduces the corpus cavernosal EMG in male rhesus macaque.
文摘The extreme large miter gates of TGP permanent shiplock are of great difficulty in erection,in view of the stringent requirement of precision control and the complicated components.The major erection problems,such as the erection measurement control, the selection of erection position of gate leaf,welding and deformation manipulation,the erection of back tie rods,the installation of apex pintle and prestressing anchorages,etc., had been carefully deliberated, and the optimized approaches were adopted.The erection practice of the miter gate at No.1 lock head shows that the adopted erection technology is safe,reliable and effective, and it may be used for reference for similar miter gates.
文摘Deformation and dislocations of segments of shield tunnel in construction stage have apparent effect on tunnel structure stress and even cause local cracks and breakage in tunnel. 3D finite element method was used to analyze two segment ring models under uniform injected pressure: (1) segment ring without wedge-shaped segment, which has 16 types of preinstall erection tolerance; (2) segment ring with wedge-shaped segment, which has no preinstall erection tolerance. The analysis results indicate that different erection tolerances can cause irregular deformation in segment ring under uniform injected pressure, and that the tolerance values are enlarged further. Wedge-shaped segment apparently affects the overall deformation of segment ring without erection tolerances. The uniform injected pressure can cause deformation of ring with wedge-shaped segment irregular, and dislocations also appear in this situation. The stress of segment with erection tolerances is much larger than that of segment without erection tolerances. Enlarging the central angle of wedge-shaped segment can make the irregular deformation and dis- locations of segments smaller. The analysis results also provide basis for erection tolerance control and improvement of segment constitution.
文摘In contrast to the spinal control of erection, relatively little is known about the brain control. In the present review, we have outlined the role of brain structures involved in penile erection and provided a synopsis on the brain circuit of erection. Findings from both animal and human studies are discussed. Evidence suggests that the most important structures are the frontal lobe, cingulate gyrus, amygdala, thalamus and hypothalamus. Within the brain circuit of erection, the thalamus serves as a gate-controller in which all relevant information is evaluated and further processed to higher and lower centres.
文摘In this work, the aerodynamic stability of the Yichang Suspension Bridge over Yangtze River during erection was determined by three-dimensional nonlinear flutter analysis, in which the nonlinearities of structural dynamic characteristics and aeroelastic forces caused by large deformation are fully considered. An interesting resuh obtained was that the bridge was more stable when the stiffening girders were erected in a non-symmetrical manner as opposed to the traditional symmetrical erection schedule. It was also found that the severe decrease in the aerodynamic stability was due to the nonlinear effects. Therefore, the nonlinear factors should be considered accurately in aerodynamic stability analysis of long-span suspension bridges during erection.
文摘Aim: Epididymal proteins are known to play an important role in the maturation of spermatozoa, we ought to deter-mine if there are regional differences in androgen-dependent epididymal proteins. Methods: A group of adult rats wascastrated and epididymides were removed three days following castration. The epididymides were dissected into caput,corpus and cauda segments, homogenized, and proteins were fractionated by anion exchange HPLC. Proteins in select-ed fractions were resolved by SDS-PAGE and visualized by silver staining. Results: It was observed that the levels ofmultiple proteins drastically reduced in the various regions of epididymis of the orchiectomized rats. Conclusion: Theepididymal proteins appear to be useful markers to study androgenic action in the epididymis.
文摘Aim: To investigate a possible potentiation effect of apomorphine (APO) on sildenafil-induced penile erection in the conscious rabbit. Methods: Erection of male New Zealand White rabbits (3.5-4.0 kg, n=12) was assessed by measuring the length of the uncovered penile mucosa and the duration of erection before and after intravenous administration of agents. After injection of APO (0, 0.05, 0.1 and 0.4 mg/kg), sildenafil was administered intravenously in a dose-response manner (0.5, 1 and 5 mg/kg). In additional experiments, the effect of increasing doses of sildenafil in combination with APO on systemic blood pressure was evaluated. Results: Systemic administration of sildenafil induced a dose-dependent increase in the penile length. Intravenous injection of APO alone did not produce any change in the penile length, while significantly enhanced the penile erection induced by sildenafil. The co-administration of 0.1 mg/kg of APO and 1 mg/kg of sildenafil was found to be the most effective combination in producing penile erection. Intravenous administration of sildenafil caused a concentration-dependent decrease in systemic blood pressure, but no additional decrease was observed with co-administration of APO. Conclusion: APO enhances the penile erection induced by sildenafil in the conscious rabbit without causing an additional decrease in blood pressure.