RESUMO
Studies increasingly show that social connectedness plays a key role in determining survival, in addition to natural and anthropogenic environmental factors. Few studies, however, integrated social, non-social and demographic data to elucidate what components of an animal's socio-ecological environment are most important to their survival. Female giraffes (Giraffa camelopardalis) form structured societies with highly dynamic group membership but stable long-term associations. We examined the relative contributions of sociability (relationship strength, gregariousness and betweenness), together with those of the natural (food sources and vegetation types) and anthropogenic environment (distance from human settlements), to adult female giraffe survival. We tested predictions about the influence of sociability and natural and human factors at two social levels: the individual and the social community. Survival was primarily driven by individual- rather than community-level social factors. Gregariousness (the number of other females each individual was observed with on average) was most important in explaining variation in female adult survival, more than other social traits and any natural or anthropogenic environmental factors. For adult female giraffes, grouping with more other females, even as group membership frequently changes, is correlated with better survival, and this sociability appears to be more important than several attributes of their non-social environment.
Assuntos
Girafas , Animais , Meio Ambiente , Feminino , Alimentos , Fatores SociológicosRESUMO
The effects of menopausal status and age on the intra-operative and post-operative pathology results of patients operated on with a pre-operative diagnosis of complex hyperplasia with atypia (CHA) were assessed. A hundred and eleven patients diagnosed in our centre between January 1993 and March 2013 were included. Cancer was detected in the paraffin blocks (PBs) of 52 (46.8%) patients. Among these, 50 patients had stage-IA disease. In 31.1% of the pre-menopausal patients and 66% of the post-menopausal patients, PB revealed cancer (p < 0.0001). The results of frozen section (FS) and PB were concordant in 51% and 70% in the pre-menopausal and post-menopausal patients, respectively (p = 0.041). In the patients operated on with a pre-operative diagnosis of CHA, the probability of detecting cancer in PB increases with increasing age and menopause. The reliability of FS is limited in younger and pre-menopausal patients.
Assuntos
Fatores Etários , Hiperplasia Endometrial/patologia , Neoplasias do Endométrio/patologia , Pós-Menopausa , Pré-Menopausa , Adulto , Idoso , Hiperplasia Endometrial/cirurgia , Neoplasias do Endométrio/diagnóstico , Feminino , Secções Congeladas , Humanos , Pessoa de Meia-Idade , Inclusão em ParafinaRESUMO
Population dynamics in group-living species can be strongly affected both by features of sociality per se and by resultant population structure. To develop a mechanistic understanding of population dynamics in highly social species we need to investigate how processes within groups, processes linking groups, and external drivers act and interact to produce observed patterns. We model social group dynamics in cooperatively breeding meerkats, Suricata suricatta, paying attention to local demographic as well as dispersal processes. We use generalized additive models to describe the influence of group size, population density, and environmental conditions on demographic rates for each sex and stage, and we combine these models into predictive and individual-based simulation models of group dynamics. Short-term predictions of expected group size and simulated group trajectories over the longer term agree well with observations. Group dynamics are characterized by slow increases during the breeding season and relatively sharp declines during the pre-breeding season, particularly after dry years. We examine the demographic mechanisms responsible for environmental dependence. While individuals appear more prone to emigrate after dry years, seasons of low rainfall also cause reductions in reproductive output that produce adult-biased age distributions in the following dispersal season. Adult subordinates are much more likely to disperse or be evicted than immature individuals, and demographic structure thus contributes to crashes in group size. Our results demonstrate the role of social structure in characterizing a population's response to environmental variation. We discuss the implications of our findings for the population dynamics of cooperative breeders and population dynamics generally.
Assuntos
Ecossistema , Herpestidae/fisiologia , Reprodução/fisiologia , Comportamento Social , Animais , Simulação por Computador , Feminino , Masculino , Modelos Biológicos , Dinâmica Populacional , Fatores de TempoRESUMO
OBJECTIVE: The aim of this study was to evaluate the effect of combined hearing and tinnitus masking devices that are appropriately programmed for acoustic stimulations using wide-band noise over the specific frequency range of tinnitus. MATERIAL AND METHODS: A total of 21 patients were randomly divided into 2 groups. Group I (12 patients) was managed with betahistine dihydrochloride (2HCl) and fitted either with a combined hearing aid or a sound generator, and group II (9 patients) was treated with betahistine 2HCl for 3 months. Audiological tests, pitch matching to determine the frequency of tinnitus, an assessment of tinnitus severity, and subjective scores (visual analog scale, VAS; Mini-Tinnitus Questionnaire) were used to assess the patients in both groups, and a loudness scale was also analyzed in group I. The results were evaluated in a double-blinded manner. RESULTS: Significant decreases in the severity of tinnitus, Mini-Tinnitus Questionnaire score and VAS were observed in both groups. No significant differences were obtained in pitch-matched frequency of tinnitus in the two groups. CONCLUSION: The findings obtained using either the combined devices or the masking devices with wide-band masking demonstrate that these devices are an effective tinnitus treatment alternative.
Assuntos
Estimulação Acústica/métodos , beta-Histina/uso terapêutico , Agonistas dos Receptores Histamínicos/uso terapêutico , Zumbido/tratamento farmacológico , Zumbido/terapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Método Duplo-Cego , Feminino , Auxiliares de Audição , Testes Auditivos , Humanos , Masculino , Pessoa de Meia-Idade , Percepção da Altura Sonora , Estudos Prospectivos , Inquéritos e Questionários , Zumbido/fisiopatologia , Resultado do TratamentoRESUMO
Penile fracture is an uncommon and emergent urologic condition defined as traumatic rupture of the corpus cavernosum secondary to a blunt trauma of the erect penis. Tunica albuginea is thinned and stretched in the erect state, and a transverse tear in the corpus cavernosums may occur by a buckling force. However, penile dorsal vein tears may mimic penile fracture. Also, corporeal infection and purulent cavernositis are associated with trauma, cavernosography, priapism, intracavernosal injection therapy and penile prosthesis.
Assuntos
Doenças do Pênis/patologia , Doenças do Pênis/terapia , Implante Peniano , Pênis/lesões , Adulto , Humanos , Masculino , RupturaRESUMO
The use of ureteral stents is a common procedure in urology practice. We investigated whether the use of double-J stent had an effect on sexual functions or not. One hundred and seventy-seven cases were included in the study. Unilateral double-J stent was placed during ureteral stone treatment in one hundred and eight of these cases. Sixty-nine cases were included as the control group. 'International Index of Erectile Function' (IIEF) and 'Female Sexual Function Index' (FSFI) questionaries were assessed before and 4 weeks after the intervention in all patients. When total IIEF and subdomains of IIEF scores of men and total FSFI and subdomains of FSFI scores of women whom double-J stent was placed were evaluated before and after the procedure, there was statistically significant reduction in patient's scores. In the control group, any statistically significant alteration in patient's score was not observed in men and women. Sexual functions are negatively affected in both women and men whom ureteral stents are placed. To reduce these problems specific to urinary system owing to stents, new treatment strategies and new studies that lead to improvements in the material and design of stents are required.
Assuntos
Disfunção Erétil , Cateterismo Urinário/efeitos adversos , Adulto , Humanos , Masculino , Estudos Prospectivos , Inquéritos e QuestionáriosRESUMO
Natural populations are increasingly threatened with collapse at the hands of anthropogenic effects. Predicting population collapse with the help of generic early warning signals (EWS) may provide a prospective tool for identifying species or populations at highest risk. However, pattern-to-process methods such as EWS have a multitude of challenges to overcome to be useful, including the low signal-to-noise ratio of ecological systems and the need for high quality time series data. The inclusion of trait dynamics with EWS has been proposed as a more robust tool to predict population collapse. However, the length and resolution of available time series are highly variable from one system to another, especially when generation time is considered. As yet, it remains unknown how this variability with regards to generation time will alter the efficacy of EWS. Here we take both a simulation- and experimental-based approach to assess the impacts of relative time series length and resolution on the forecasting ability of EWS. We show that EWS' performance decreases with decreasing time-series length. However, there was no evident decrease in EWS performance as resolution decreased. Our simulations suggest a relative time series length between 10 and five generations as a minimum requirement for accurate forecasting by abundance-based EWS. However, when trait information is included alongside abundance-based EWS, we find positive signals at lengths one-half of what was required without them. We suggest that, in systems where specific traits are known to affect demography, trait data should be monitored and included alongside abundance data to improve forecasting reliability.
Assuntos
Ecossistema , Animais , Fenótipo , Dinâmica Populacional , Estudos Prospectivos , Reprodutibilidade dos TestesRESUMO
BACKGROUND AND AIM: Epicardial adipose tissue (EAT), which is thought to be a component of visceral adiposity, is associated with the metabolic syndrome. We aimed to test the hypothesis that echocardiographic EAT thickness can be a marker for the presence and severity of coronary artery disease (CAD). METHOD AND RESULTS: In all, 150 patients (100 patients with CAD and 50 patients with normal coronary arteries by diagnostic coronary angiography; 65 women, 85 men; mean age 55.7+/-7.4 years) were enrolled. EAT thickness was measured using 2-D echocardiographic parasternal long- and short-axis views. EAT thickness measurements were compared with angiographic findings. EAT thickness was significantly higher in patients with CAD in comparison to those with normal coronary arteries (6.9+/-1.5 mm vs. 4.4+/-0.8 mm; P<0.001). Furthermore, EAT thickness increased with the severity of CAD (multivessel disease 7.4+/-1.2 mm vs. single vessel disease 5.7+/-1.7 mm; P<0.001). Gensini's score significantly correlated with EAT thickness (r=0.600, P<0.001). EAT thickness of > or = 5.2 mm had 85% sensitivity and 81% specificity (ROC area 0.914, P<0.001, 95% CI [0.86-0.96]) for predicting CAD. CONCLUSION: EAT thickness, which is easily and non-invasively evaluated by transthoracic echocardiography, can be an adjunctive marker to classical risk factors for the prediction of CAD.
Assuntos
Tecido Adiposo/diagnóstico por imagem , Doença da Artéria Coronariana/diagnóstico por imagem , Ecocardiografia , Pericárdio/diagnóstico por imagem , Índice de Gravidade de Doença , Angiografia Coronária , Doença da Artéria Coronariana/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos TestesRESUMO
We report two human leukocyte antigen (HLA) B27-positive cases of urogenital tuberculosis (TB) with asymmetric polyarthritis. Stained smears with Ehrlich Ziehl-Neelsen and polymerase chain reaction (PCR) tests for Mycobacterium tuberculosis complex (MTC) of the ejaculate were positive in both cases, despite negative cultures. Stained smear, culture and PCR results of the synovial fluid for mycobacteria were negative. The patients were diagnosed with Poncet's disease. Polyarthritis was resolved rapidly with anti-tuberculosis treatment. We suggest that in cases with unexplained arthritis and non-articular TB, Poncet's disease should be considered. PCR can be used in the routine diagnostic algorithm when conventional methods fail to identify MTC.
Assuntos
Artrite Reativa/epidemiologia , Tuberculose Urogenital/epidemiologia , Adulto , Artrite Reativa/tratamento farmacológico , Sedimentação Sanguínea , Proteína C-Reativa/análise , Antígeno HLA-B27/análise , Humanos , Masculino , Reação em Cadeia da Polimerase , Tuberculose Urogenital/sangue , Tuberculose Urogenital/diagnósticoRESUMO
We designed a study consisting of 27 consecutive patients with erectile dysfunction in order to evaluate the role of cavernous oxygen tension. Patients were completely evaluated by history, physical examination, multiple blood analyses, serum testosterone level measurements, papaverine test, color duplex sonography and dynamic infusion cavernosometry-cavernosography. Blood gas samples were obtained from femoral artery and corpus cavernosum before drug injection and also from corpus cavernosum at 5, 10, 20, 30, 40 min following drug injection. Aetiologic classification of erectile dysfunction in our patients was as follows: psychogenic in 8, cavernosal failure in 14 and arterial disease in 5 cases. At flaccidity, no significant differences were found in the mean pO2, sO2, pCO2 and pH values of patient groups. After injection of intracavernous papaverine, results of the cavernous pO2 (P < 0.05), sO2 (P < 0.05) levels were found to be statistically significantly different between patients with vascular and psychogenic erectile dysfunction. Analysis of maximal cavernosal oxygen tension and PSV revealed statistically significant correlation (r = 0.66, P < 0.001). The results of this study suggest that changes in arterial and cavernosal pO2 and sO2 values may be contributing factors or co-factors in erectile failure.
Assuntos
Disfunção Erétil/sangue , Oxigênio/sangue , Pênis/irrigação sanguínea , Adulto , Idoso , Artérias , Gasometria , Dióxido de Carbono/sangue , Disfunção Erétil/psicologia , Artéria Femoral , Humanos , Concentração de Íons de Hidrogênio , Impotência Vasculogênica/sangue , Cinética , Masculino , Pessoa de Meia-Idade , Papaverina , VasodilatadoresRESUMO
Although back pain is very common, the differential diagnosis may sometimes be very difficult. Both inflammation and infections of spinal or sacroiliac joints are examples of such causes. We report three cases of brucella sacroiliitis resembling acute low back pain or lumbar disc herniation. All patients had had a recent infection and were referred complaining of acute back pain with a suspicion of lumbar disc herniation. The complaints of all patients reduced dramatically after proper medication. Radiographs of all patients and bone scans of two patients revealed sacroiliitis. One of the patients was positive for HLA-B27; in the other two patients HLA-B27 could not be determined.
Assuntos
Artrite Reativa/microbiologia , Brucelose/microbiologia , Articulação Sacroilíaca , Doença Aguda , Adulto , Artrite Reativa/diagnóstico por imagem , Artrite Reativa/imunologia , Brucelose/diagnóstico por imagem , Brucelose/imunologia , Antígeno HLA-B27/análise , Humanos , Dor Lombar/diagnóstico por imagem , Dor Lombar/imunologia , Dor Lombar/microbiologia , Masculino , Radiografia , Articulação Sacroilíaca/diagnóstico por imagem , Articulação Sacroilíaca/microbiologiaRESUMO
In this study, we examined scalp recorded dermatomal somatosensory evoked potentials (DSEPs) to electrical stimulation of L4, L5 and S1 dermatomes in 55 patients with proven lumbosacral radiculopathy and in 22 healthy subjects. We did not observe any significant ipsilateral intertrial variations and arithmetic mean side-to-side differences in normal subjects. As for segmental latencies, the dermatomal P40 latencies were directly correlated with height. The regression equations for L4, L5 and S1 dermatomes were as follows: (L4) y = 5.8 + 21.3 (height), (L5) y = -2.09 + 28.04 (height), (S1) y = -13.9 + 36.4 (height). Maximum side-to-side latency differences and maximum P 40 latencies were obtained by adding 2 standard deviations to the arithmetic means. The abnormal latencies for L4, L5 and S1 dermatomes were 48 msec., 52 msec., and 55 msec., respectively. The abnormal side-to-side latency difference were 3 msec. for all dermatomes. DSEPs accurately predicted the lesion only in four patients (7.2%). In 20 patients (36.3%), DSEPs correctly identified the lesion but also gave misleading information on the other levels. DSEP abnormality were on the correct level but opposite side in 5 patients (9%). The findings were normal in 11 patients (20%), and misleading in 15 patients (27.2%). We conclude that the ultimate diagnostic utility of DSEPs in lumbosacral radiculopathies is doubtful and controversial needs further investigations.
Assuntos
Potenciais Somatossensoriais Evocados/fisiologia , Deslocamento do Disco Intervertebral/fisiopatologia , Adulto , Idoso , Estimulação Elétrica , Eletromiografia , Lateralidade Funcional/fisiologia , Humanos , Vértebras Lombares , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , SacroRESUMO
We evaluated the effectiveness of sildenafil citrate on lower urinary system symptoms (LUTS) by using symptom score scales. We also evaluated whether or not the presence of asymptomatic inflammatory prostatitis had an effect on the alteration in the symptom scores. A total of 36 male patients were included in the study. For all the cases, 'International Prostate Symptom Score' (IPSS), 'National Health Institute Chronic Prostatitis Symptom Index' (NIH-CPSI) and 'International Index of Erectile Function' (IIEF-5) were investigated and the scores were calculated in the first visit. Sildenafil citrate was given for 30 days and at the second visit IPSS, NIH-CPSI and IIEF-5 scores were once more analyzed. Afterwards, the alterations of the scores between visits were statistically compared. Mean age of the 36 cases included in the study was 59.03±1.35. When the alterations in parameters of first visit and second visit were evaluated, we found a statistically significant increase in IIEF-5 and a statistically significant decrease in IPSS, IPSS-QOL (Quality of Life). In addition, when the cases were divided into two groups with and without asymptomatic inflammatory prostatitis, in the cases with asymptomatic inflammatory prostatitis, sildenafil citrate caused improvement only in ED, but had no effect on LUTS. Sildenafil citrate use in cases with LUTS and ED has an improving effect on LUTS as well as ED. However, in cases with asymptomatic inflammatory prostatitis, sildenafil citrate did not lead to an improvement in LUTS.
Assuntos
Disfunção Erétil/tratamento farmacológico , Inibidores da Fosfodiesterase 5/uso terapêutico , Piperazinas/uso terapêutico , Prostatite/complicações , Sulfonas/uso terapêutico , Doenças Urológicas/tratamento farmacológico , Idoso , Disfunção Erétil/complicações , Indicadores Básicos de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Purinas/uso terapêutico , Qualidade de Vida , Citrato de Sildenafila , Resultado do Tratamento , Doenças Urológicas/complicaçõesRESUMO
INTRODUCTION: The purpose of this study was to investigate the results of minimally invasive treatment modalities in early stage multiloculated empyema thoracis. METHODS: The minimally invasive treatment modalities of 114 patients with Class 5 thoracic empyema were retrospectively reviewed. The patients' demographics, symptoms, diagnostic studies, treatment options and complications were evaluated. RESULTS: A total of 47 patients underwent tube thoracostomy, 23 patients underwent fibrinolytic therapy with streptokinase and 44 patients underwent video-assisted thoracoscopic surgery (VATS) deloculation and debridement. No statistical differences were found in the patients' age, gender, Gram stain and antibiotherapy before intervention among the groups. Illness days before intervention was significantly longer in the tube thoracostomy group than in the others. The VATS group had a shorter drainage time and hospital stay than the others. The VATS and fibrinolytic therapy groups had lower complication rates and less open decortication requirements than the tube thoracostomy group. Success rates were 66, 95 and 100 percent in the tube thoracostomy, fibrinolytic therapy and VATS groups, respectively. In total, there were 35 patients with complications. The most frequent complication was air space. Two inhospital mortalities occurred. CONCLUSION: In patients with early stage multiloculated empyema, VATS deloculation and debridement is superior to tube thoracostomy alone and fibrinolitic therapy in reducing drainage time and hospital stay. It has a relatively high success rate without significant morbidity. Therefore, VATS decortication may be recommended as a first-line therapy in early stage multiloculated empyema thoracis.
Assuntos
Empiema Pleural/cirurgia , Fibrinolíticos/uso terapêutico , Estreptoquinase/uso terapêutico , Cirurgia Torácica Vídeoassistida , Toracostomia/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Tubos Torácicos , Empiema Pleural/tratamento farmacológico , Empiema Pleural/terapia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Estudos Retrospectivos , Toracostomia/instrumentação , Fatores de Tempo , Resultado do Tratamento , Adulto JovemRESUMO
The organized management of spinal cord injury is a team activity and the nurse is at the central position of that team. Nursing activities and caring should be superior in a spinal cord injury rehabilitation department. Nevertheless, nurses seldom undertake caring activities and usually perform therapeutic activities in developing countries. We recorded the care of 15 spinal cord injured patients around the clock for 10 working days. We asked the nurses, patients and their family carers to record every activity they performed on the forms. The activities were as follows: Oral care, face care, hand care, foot care, nail care, genitalia care, perineal care, catheterization, head bath, bed bath, bath, positioning, mobilization, exercising, wound dressing, room activities and the other nursing activities. The total number of nursing activities, performed was 3573. Subtotals were as follows: 2545 caring activities, 364 room activities, and 664 other nursing activities. While nurses performed 550 of the caring activities, patients and their family carers performed 988 and 1007 patient care activities. The distribution of the nurses' activities was as follows: 40% for caring, 11% for room activities, 48% for others. We discuss the importance of caring activities and the role of nurses in the rehabilitation team.
Assuntos
Cuidados de Enfermagem/normas , Centros de Reabilitação/normas , Traumatismos da Medula Espinal/enfermagem , Traumatismos da Medula Espinal/reabilitação , Adolescente , Adulto , Feminino , Pesquisas sobre Atenção à Saúde , Humanos , Escala de Gravidade do Ferimento , Masculino , Cuidados de Enfermagem/tendências , Garantia da Qualidade dos Cuidados de Saúde , Traumatismos da Medula Espinal/classificação , TurquiaRESUMO
The effects of unilateral testicular torsion on the blood flow of the contralateral testis were investigated. Fourteen adult male dogs were recruited. Seven dogs underwent unilateral testicular torsion of 4 h duration, and the other seven dogs had a control operation. Testicular blood flow was determined by colour Doppler ultrasonography before and after the testicular torsion. Bilateral orchidectomy was performed at the end of the study and histopathological changes were evaluated. Values of peak systolic velocity, end diastolic velocity, and resistive index were not statistically significant between ipsilateral and contralateral testes in the study group (p > 0.05). On comparison with the control group, blood flow in the contralateral testes showed no statistically significant difference (p > 0.05). Oedema and congestion were seen on ipsilateral testes in the study group. No histopathological changes were noted on the contralateral testes. Minimal oedema and congestion secondary to manipulation were found in the control operation testes. We conclude that unilateral testicular torsion does not decrease contralateral testicular blood flow as shown by colour Doppler ultrasonography.
Assuntos
Torção do Cordão Espermático/patologia , Testículo/irrigação sanguínea , Animais , Cães , Masculino , Orquiectomia , Fluxo Sanguíneo Regional , Estatísticas não Paramétricas , Testículo/diagnóstico por imagem , Ultrassonografia Doppler em CoresRESUMO
Recent studies have shown an important role for nitric oxide (NO) in cavernous smooth muscle relaxation. In this study the intracavernosal effects of the NO donor sodium nitroprusside (SNP) were investigated in 32 patients with erectile dysfunction. Erectile response and penile blood flow were investigated following intracavernosal administration of 360 micrograms SNP and 60 mg papaverine for diagnostic purposes. In all of 32 patients the erectile response to SNP was not better than that to papaverine. Haemodynamic evaluation of the deep penile arteries was carried out by colour duplex Doppler sonography after administration of SNP and papaverine. No differences in peak flow velocities were measured, but the increases in diameter and end-diastolic velocities were higher after SNP than after papaverine. Our data suggest that the NO donor SNP is not a new alternative agent for diagnosis and treatment of impotence.
Assuntos
Impotência Vasculogênica/tratamento farmacológico , Músculo Liso Vascular/efeitos dos fármacos , Nitroprussiato/administração & dosagem , Vasodilatadores/administração & dosagem , Adulto , Idoso , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Vias de Administração de Medicamentos , Humanos , Impotência Vasculogênica/diagnóstico por imagem , Impotência Vasculogênica/fisiopatologia , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/fisiopatologia , Papaverina/administração & dosagem , Ereção Peniana/efeitos dos fármacos , Pênis/irrigação sanguínea , Pênis/diagnóstico por imagem , Estudos Prospectivos , Estudos Retrospectivos , Ultrassonografia Doppler DuplaRESUMO
The contractile effect of oxytocin on isolated rabbit corpus cavernosum strips was investigated. Concentration-response curves to oxytocin and phenylephrine were obtained. Oxytocin repetitively induced concentration-dependent contractions in the corpus cavernosum strips. The maximal contractile response to oxytocin was in amplitude 39.4 +/- 9.1% of that to phenylephrine. The slopes of the concentration-response curves, the amplitude of the maximal contractile effects, and the pD2 values of oxytocin obtained in endothelium-denuded strips were not significantly different from those of intact preparations. The results of this study demonstrated that oxytocin contracts the rabbit corpus cavernosum, but the endothelium does not contribute to this effect. Since oxytocin is less efficacious than phenylephrine, it seems unlikely that this hormone can serve as an alternative in the treatment of prolonged penile erections.