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1.
Andrologia ; 42(6): 389-94, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21105890

RESUMO

Maturation arrest (MA) of spermatogenesis is diagnosed on histology as interruption of spermatogenesis before the final stage without impairment of Sertoli or Leydig cells. It is considered a condition of irreversible or absolute infertility. Varicocele, which represents impairment in the testicular venous drainage system, has been shown to be a bilateral disease. Malfunction of the valves increase the hydrostatic pressure in the testicular venous system that exceeds the pressure in the arterial system leading to hypoxia in the testicular microcirculation and in the seminiferous tubules, the sperm production site. Sperm production deteriorates, and ultimately progresses to azoospermia. Our prediction was that MA, if genetic factors are excluded, is the final stage of long standing hypoxia. This would indicate that MA is not always an independent disease entity, but may represent progressive process of deterioration of the testicular parenchyma beyond azoospermia. By histology and electron microscopy, our prediction confirmed, at least partially, that MA is associated with degenerative ischaemic changes in the seminiferous tubules. Adequate treatment of bilateral varicocele by microsurgery or super-selective sclerotherapy of the internal spermatic veins including associated network of venous bypasses, vertically oriented, may resume the flow of oxygenated blood. If irreversible damages did not occur and ischaemia is not too long standing, limited sperm production may be restored, at least partially.


Assuntos
Azoospermia/complicações , Hipóxia/complicações , Maturação do Esperma , Varicocele/complicações , Humanos , Isquemia/complicações , Masculino , Microcirurgia , Pênis/irrigação sanguínea , Escleroterapia , Túbulos Seminíferos/patologia , Síndrome de Células de Sertoli/patologia , Espermatogênese , Testículo/irrigação sanguínea , Varicocele/cirurgia
2.
Andrologia ; 42(5): 314-21, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20860630

RESUMO

Sertoli-cell-only (SCO) syndrome, or germ cell aplasia, is diagnosed on testicular biopsy when germ cells are seen to be absent without histological impairment of Sertoli or Leydig cells. It is considered a situation of irreversible infertility. Recent studies have shown that varicocele, a bilateral disease, causes hypoxia in the testicular microcirculation. Destruction of one-way valves in the internal spermatic veins (ISV) elevates hydrostatic pressure in the testicular venules, exceeding the pressure in the arteriolar system. The positive pressure gradient between arterial and venous system is reversed, causing hypoxia in the sperm production site. Sperm production deteriorates gradually, progressing to azoospermia. Our prediction was that, if genetic problems are excluded, SCO may be the final stage of longstanding hypoxia which deteriorates sperm production in a progressive process over time. This would indicate that SCO is not always an independent disease entity, but may represent deterioration of the testicular parenchyma beyond azoospermia. Our prediction is confirmed by histology of the seminiferous tubules demonstrating that SCO is associated with extensive degenerative ischaemic changes and destruction of the normal architecture of the sperm production site. Adequate treatment of bilateral varicocele by microsurgery or by selective sclerotherapy of the ISV resumes, at least partially, the flow of oxygenated blood to the sperm production site and restored sperm production in 4 out of 10 patients. Based on our findings the following statements can be made: (i) SCO may be related in part of the cases to persistent, longstanding testicular parenchymal hypoxia; (ii) germ cells may still exist in other areas of the testicular parenchyma; and (iii) if genetic problems are excluded, adequate correction of the hypoxia may restore very limited sperm production in some patients.


Assuntos
Azoospermia/etiologia , Drenagem/efeitos adversos , Hipóxia/complicações , Síndrome de Células de Sertoli/etiologia , Testículo/irrigação sanguínea , Azoospermia/diagnóstico , Azoospermia/terapia , Humanos , Hipóxia/cirurgia , Masculino , Microcirurgia , Escleroterapia , Síndrome de Células de Sertoli/diagnóstico , Síndrome de Células de Sertoli/terapia , Espermatogênese , Varicocele/cirurgia , Veias/cirurgia
3.
J Med Educ ; 51(09): 726-34, 1976 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-957388

RESUMO

This is a report of student marriages as perceived by spouses of medical students at the Southwestern Medical School, University of Texas Health Science Center at Dallas. Between August and November 1974 a questionnaire was sent to all spouses (239) of sophomore, junior, and senior students and 1974 graduates. The questionnaire examined: areas of stress within marriage, congruence between expected and actual behavior in the marital partner's role performance, and the spouse's attitudes toward marital counseling and whether a marital counseling service should be made available. Stress factors frequently cited were student's preoccupation due to school pressures, limited finances for recreation and nonessentials, student's inaccessibility due to school and loneliness. Most respondents stated satisfaction with their marriage; however, 38 percent indicated that their marriage could have benefited from counseling some time during medical school.


Assuntos
Casamento , Estudantes de Medicina , Adulto , Comunicação , Aconselhamento , Frustração , Humanos , Michigan , Estresse Psicológico
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