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1.
Urology ; 54(3): 548-52, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10475370

RESUMO

OBJECTIVES: To evaluate the incidence and sites of retroperitoneal recurrence after modified retroperitoneal lymph node dissection (RPLND) for low-stage nonseminomatous germ cell tumors (NSGCTs). METHODS: A retrospective review of 88 patients who underwent RPLND for Stage I or II NSGCTs between 1971 and 1991 was performed to determine the incidence and site of any retroperitoneal recurrence. RESULTS: Six retroperitoneal recurrences (four isolated and two in conjunction with failures at other sites) were found with a minimum follow-up of 5 years. All 6 patients had left-sided primary tumors, with three recurrences near the left renal hilum and two near the right renal hilum. All recurrences were at or outside the boundaries of the surgical dissection. Only one retroperitoneal recurrence may have been prevented by performing a bilateral dissection. CONCLUSIONS: Although uncommon, local recurrences can occur after RPLND. The right and especially the left renal hilum appear to be at higher risk of failure, possibly because of incomplete dissection in these areas. A more complete dissection in these areas may further decrease the local recurrence rate. Overall, the data presented and the studies reviewed suggest that modified RPLND reliably removes metastatic tumor with a low failure rate. If failures do occur, they are usually outside of the template and would not necessarily be prevented with a complete bilateral infrahilar dissection.


Assuntos
Germinoma/epidemiologia , Germinoma/cirurgia , Excisão de Linfonodo , Neoplasias Retroperitoneais/epidemiologia , Neoplasias Retroperitoneais/secundário , Neoplasias Testiculares/patologia , Neoplasias Testiculares/cirurgia , Seguimentos , Germinoma/secundário , Humanos , Incidência , Masculino , Estadiamento de Neoplasias , Estudos Retrospectivos
2.
J Urol ; 159(5): 1606-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9554363

RESUMO

PURPOSE: Many investigators use prostate rebiopsy as an indicator of treatment efficacy and tumor response of localized prostate cancer for therapies in which the gland remains in situ. Because of the inherent sampling error of needle directed biopsies, however, some men will have a false-negative rebiopsy even if they have had no therapy or if the therapeutic intervention was unsuccessful in eradicating the malignancy. We evaluate the risk of a false-negative biopsy and the clinical factors that influence this risk. MATERIALS AND METHODS: A total of 90 patients undergoing radical prostatectomy for clinically localized disease underwent sextant biopsy of the prostate immediately after removal of the gland. Data collected included prostate specific antigen (PSA), hormonal status, age and biopsy core status. RESULTS: Of the total study population 67.8% received neoadjuvant hormonal therapy. While all patients had pathologically confirmed adenocarcinoma within the prostatectomy specimen, 45.6% demonstrated a false-negative rebiopsy. Within a combined predictive model, PSA and hormonal status demonstrated a statistically significant effect on the false-negative rebiopsy rate. Predictive power of this combined model was high across the spectrum of risk for a false-negative rebiopsy. CONCLUSIONS: This series demonstrates that the risk of a false-negative sextant biopsy in the presence of documented prostate cancer is high and is affected by several factors, including PSA and hormonal status. These data suggest that prostate sextant rebiopsy is an inaccurate method of assessing the therapeutic efficacy of treatments for carcinoma of the prostate in which the gland remains in situ following therapy.


Assuntos
Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Prostatectomia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/cirurgia , Adenocarcinoma/sangue , Idoso , Biópsia , Reações Falso-Negativas , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Próstata/patologia , Antígeno Prostático Específico/análise , Neoplasias da Próstata/sangue , Curva ROC , Resultado do Tratamento
3.
J Endourol ; 11(2): 125-30, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9107586

RESUMO

Percutaneous nephrolithotomy remains an important technique for managing complicated nephrolithiasis. Retrograde percutaneous nephrostomy creation has been promoted as an alternative to the standard antegrade technique. We reviewed our first 41 consecutive attempts utilizing the Lawson technique for managing patients with complicated nephrolithiasis. Percutaneous access was achieved in 40 attempts (98%). Thirty-six (90%) of the retrograde nephrostomy tracts were adequate for lithotripsy or stone extraction during the same anesthetic. Twenty-three (56%) of the kidneys treated with the Lawson procedure were rendered stone free. Nine patients had minimal residual stone burden (fewer than five fragments, 4 mm or smaller) by the time of discharge. A single Lawson procedure rendered 10 kidneys (24%) stone free. An additional 20 clinic procedures and 17 anesthetic procedures were performed on the 40 kidneys. Complications were minimal, with three patients (8%) requiring transfusion.


Assuntos
Cálculos Renais/terapia , Nefrostomia Percutânea/métodos , Adulto , Idoso , Feminino , Humanos , Pelve Renal , Masculino , Pessoa de Meia-Idade , Nefrostomia Percutânea/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
4.
J Urol ; 155(5): 1613-6, 1996 May.
Artigo em Inglês | MEDLINE | ID: mdl-8627835

RESUMO

PURPOSE: Information was collected during the first 2 years of an ongoing, prospective, multi-institutional evaluation of the Dura-II penile prosthesis. Evaluation included data on clinical outcomes and a patient satisfaction survey, and will continue for 5 years after implantation for each patient. MATERIALS AND METHODS: To date 196 patients have been evaluated. Surgical data, adverse events and information from satisfaction surveys are reported. RESULTS: At a followup of 13.4 +/- 8.4 months postoperatively, adverse events occurred in 8.2% of the patients, resulting in reoperation in 5.1%. There have been no mechanical failures. Overall satisfaction rates were 85% at 3 months, 83% at 1 year and 91% at 2 years after implantation, and levels of sexual functioning were correspondingly high. A majority of patients assigned high scores to rigidity, concealability, ability to have intercourse and erection size, although satisfaction with erection size ranked lower than the other measures. CONCLUSIONS: The Dura-II penile prosthesis provides a satisfactory result and has an acceptable level of complications associated with its use. Further followup will assess temporal changes in satisfaction rates and sexual functioning for these patients.


Assuntos
Disfunção Erétil/cirurgia , Prótese de Pênis , Adulto , Idoso , Idoso de 80 Anos ou mais , Disfunção Erétil/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Prospectivos , Desenho de Prótese , Resultado do Tratamento
5.
J Urol ; 155(2): 757-62, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8558720

RESUMO

PURPOSE: The in vitro effects of the fluoroquinolone antibiotics ciprofloxacin and ofloxacin upon 3 human transitional cell carcinoma cell lines were investigated at concentrations that are attainable in the urine of patients taking these drugs orally. MATERIALS AND METHODS: Cell lines TCCSUP, T24, and J82 were exposed in culture to either ciprofloxacin or ofloxacin at concentrations ranging from 0 to 800 micrograms./ml. and at durations ranging from 24 to 120 hours. Inhibition of proliferation and DNA synthesis were assessed via MTT and tritiated thymidine assays, respectively. RESULTS: From the MTT assay ciprofloxacin, at concentrations of 25 to 800 micrograms./ml., produced proliferation inhibition in the TCCSUP line ranging from 8.1% to 90.2% at 24 hours, 25.1% to 94.9% at 72 hours, and 53.8% to 96.9% at 120 hours. Inhibition of proliferation for the T24 line ranged from 8.0% to 85%, 31.5% to 96.5%, and 27.3% to 98.2%. Inhibition of proliferation of the J82 line ranged from 20.8% to 84.8%, 22.8% to 92.7%, and 37.4% to 97.1%. Inhibition of DNA synthesis (due to ciprofloxacin at the concentrations above) as measured by the tritiated thymidine assay was also significant for each of the 3 cell lines. Inhibition of proliferation and DNA synthesis due to ofloxacin was lower but not overall statistically different from that due to ciprofloxacin. In a separate experiment, enhanced cytotoxicity was observed at lower concentrations of ciprofloxacin when the initial media pH was approximated to 5.5. CONCLUSIONS: Ciprofloxacin and ofloxacin inhibit proliferation and DNA synthesis of these 3 human TCC lines in vitro. Inhibition occurred in a concentration- and time-dependent manner. The concentrations that were assessed are attainable in the urine of patients taking these agents orally.


Assuntos
Anti-Infecciosos/uso terapêutico , Carcinoma de Células de Transição/tratamento farmacológico , Ciprofloxacina/uso terapêutico , Ofloxacino/uso terapêutico , Neoplasias da Bexiga Urinária/tratamento farmacológico , Carcinoma de Células de Transição/patologia , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Fatores de Tempo , Neoplasias da Bexiga Urinária/patologia
6.
J Surg Oncol ; 61(2): 131-3, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8606544

RESUMO

Approximately 10-15% of patients with stage 1 pure seminoma of the testis have an elevated preorchiectomy serum beta human chorionic gonadotropin level [1-4]. The prognostic significance of this elevation is unknown. We performed a multi-institutional retrospective review of 332 men with stage I pure seminoma of the testis and evaluated the prognostic significance of this elevation and the prognostic value of local invasion of the primary tumor. Twenty-five of 191 evaluable patients (13%) had elevated preorchiectomy beta human chorionic gonadotropin. All normalized postoperatively and are alive without evidence of disease with a median follow-up of 50 months (range 1-124 mo). Of 191 patients, 190 (99.5%) are alive and free of disease. One patient underwent salvage chemotherapy for a chest recurrence, and he is alive and free of disease at 72 months. We conclude that elevated preorchiectomy serum beta human chorionic gonadotropin level and local invasion of the primary tumor do not portend a poor prognosis in patients with clinical stage I pure seminoma of the testis.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/análise , Seminoma/patologia , Neoplasias Testiculares/patologia , Terapia Combinada , Intervalo Livre de Doença , Humanos , Masculino , Orquiectomia , Prognóstico , Estudos Retrospectivos , Seminoma/metabolismo , Seminoma/mortalidade , Seminoma/cirurgia , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/mortalidade , Neoplasias Testiculares/cirurgia
7.
Urology ; 47(2): 250-1, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8607245

RESUMO

We describe a simple tubular elastic gauze dressing for surgical wounds of the penis. The amount of pressure placed on the penis is consistent and reproducible. The material is elastic enough to avoid vascular occlusion and is easily applied with a plastic tube. The dressing stays in place, can be used with stents or catheters, and is easily removed by the patients at home.


Assuntos
Bandagens , Pênis/cirurgia , Cuidados Pós-Operatórios , Adulto , Criança , Humanos , Masculino , Cateterismo Urinário
8.
Urol Oncol ; 2(6): 198-201, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-21224169

RESUMO

Pathologic T3 prostate cancer (extraprostatic spread) detected following radical prostatectomy reduces the likelihood of cure. We conducted this study to determine the impact of the surgical approach (retropubic versus perineal) on risk and location of pT3 disease. A retrospective analysis of 287 consecutive radical prostatectomies [III retropubic (RRP) and 176 perineal (RPP)] was conducted. Specimens were pathologically examined for presence or absence of pT3 disease. A greater rate of pT3 disease was found with RRP than with RPP, which was likely due to patient selection. Of specimens with a single positive surgical margin, the positive margin was more common at the base of the gland with RPP than with RRP (38.5% versus 9.3%). Conversely, the percentage of specimens with a positive apical margin only was less with RPP than with RRP (12.8% versus 44.2%) (Chi-square, p ≤ 0.025). These results lead us to conclude that RPP may achieve superior cancer control for tumors located at the prostate apex, while the retropubic approach may be preferred for tumors located at the prostatic base.

9.
Urology ; 46(5): 688-91, 1995 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7495122

RESUMO

OBJECTIVES: The protection of spermatogenesis during chemotherapy using an antiandrogen and a luteinizing hormone-releasing hormone (LHRH) agonist was examined in the rat. Previous studies using LHRH agonists alone have been inconclusive, as both protective and deleterious effects on the germinal epithelium have been reported. Flutamide has not previously been used in this manner but theoretically should protect the germinal epithelium, since flutamide rapidly blocks testosterone at the cellular level and also minimizes the testosterone "flare" when LHRH agonist therapy is initiated. METHODS: Mature Sprague-Dawley rats were pretreated with flutamide, sustained-release goserelin acetate (Zoladex), or a combination of flutamide and sustained-release goserelin acetate for 14 days before 4 weekly doses of procarbazine were initiated. The seminiferous tubules were evaluated histologically after a 90-day regeneration period using the stem cell assay test. RESULTS: After treatment with procarbazine alone, only 43% of the seminiferous tubules were active; however, 80% were active if protected with flutamide, 91% if protected with sustained-release goserelin acetate, and 95% if protected with both flutamide and goserelin acetate. CONCLUSION: Flutamide, sustained-release goserelin acetate, and a combination of these agents were effective in protecting the germinal epithelium of the rat during chemotherapy. A combination of flutamide and goserelin acetate provided the best protection. This study demonstrates for the first time the protective effect of flutamide and flutamide with goserelin acetate on the germinal epithelium during chemotherapy.


Assuntos
Flutamida/uso terapêutico , Gosserrelina/uso terapêutico , Procarbazina/efeitos adversos , Túbulos Seminíferos/efeitos dos fármacos , Animais , Quimioterapia Combinada , Epitélio/efeitos dos fármacos , Flutamida/farmacologia , Gosserrelina/farmacologia , Masculino , Procarbazina/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley
10.
J Urol ; 154(4): 1443-6, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7658554

RESUMO

PURPOSE: We determined whether bladder neck sparing radical prostatectomy may leave prostate tissue in the unresected bladder neck. MATERIALS AND METHODS: We intraoperatively evaluated the presence of prostate tissue in bladder neck biopsy specimens from 73 consecutive patients undergoing bladder neck sparing radical prostatectomy. RESULTS: Of the 73 specimens 14 (19%) contained prostate tissue: 9 (12%) were positive for prostate cancer and 5 (7%) contained benign prostate tissue. All patients with a positive bladder neck biopsy had a positive margin at another site. CONCLUSIONS: We recommend routine bladder neck biopsies for patients undergoing a bladder neck sparing procedure.


Assuntos
Cuidados Intraoperatórios , Prostatectomia , Neoplasias da Próstata/patologia , Bexiga Urinária/patologia , Biópsia , Humanos , Incidência , Masculino , Prostatectomia/métodos , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/cirurgia
11.
J Urol ; 154(4): 1455-6, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-7658557

RESUMO

PURPOSE: We determined the importance of hematuria in patients infected with the human immunodeficiency virus (HIV). MATERIALS AND METHODS: The records of 1,326 HIV infected patients with yearly evaluations were reviewed for hematuria and evaluation results. Mean followup was 2.1 years. RESULTS: A total of 331 patients (25.0%) had 1 episode of hematuria and 67 were evaluated with 5 significant diagnoses made. Management was affected in only 3 of these patients. No occult genitourinary tumors were found. CONCLUSIONS: In young, asymptomatic, HIV infected patients with microscopic hematuria a urological evaluation can be safely omitted in the presence of normal renal function and a benign urological history.


Assuntos
Infecções por HIV/complicações , Hematúria/complicações , Adulto , Feminino , Seguimentos , Hematúria/epidemiologia , Hematúria/etiologia , Humanos , Masculino
12.
J Pediatr Surg ; 30(10): 1488-9, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8786497

RESUMO

The authors report on a 5-month-old boy who had a simple cyst of the testis and was treated by testis-sparing cyst excision. Preoperative ultrasonography was diagnostic of a simple cyst. The patient has been without recurrence for over 2 years, and examinations have shown a normal size testis. A literature review showed only four cases of infantile simple cysts of the testis, only one of which was diagnosed preoperatively and treated by cyst excision. Four of the 5 reported cases (including ours) were diagnosed at 5 months of age. We recommend organ-preserving cyst excision in males under 1 year of age who are found to have an intratesticular lesion that is a simple cyst by ultrasound criteria.


Assuntos
Cistos/diagnóstico por imagem , Cistos/cirurgia , Doenças Testiculares/diagnóstico por imagem , Doenças Testiculares/cirurgia , Humanos , Lactente , Masculino , Ultrassonografia
13.
South Med J ; 88(8): 849-50, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7631214

RESUMO

Bladder rupture and urethral disruption are relatively common injuries associated with pelvic trauma; however, bladder herniation into a public symphysis diastasis is an unusual sequelae of pelvic trauma. We report a case of anterior bladder wall herniation into a traumatic pubic diastasis and review the literature. Recommendations focusing on avoiding possible urinary bladder complications associated with closed reduction and external fixation of the diastasis are offered.


Assuntos
Sínfise Pubiana/lesões , Doenças da Bexiga Urinária/etiologia , Adulto , Hérnia/diagnóstico por imagem , Hérnia/etiologia , Humanos , Masculino , Radiografia , Doenças da Bexiga Urinária/diagnóstico por imagem
14.
J Am Coll Surg ; 178(3): 261-5, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8149018

RESUMO

The records of 636 patients who were treated for carcinoma of the testis were reviewed. Of these patients, 61 (9.6 percent) presented with extratesticular complaints. In order of decreasing frequency, the complaints were pain (abdominal, back or groin), gynecomastia or mastodynia, pulmonary complaints, enlarged lymph nodes or a nontesticular mass, swelling of the lower extremity or neurologic changes. A substantial number of these patients were initially misdiagnosed and underwent a surgical procedure. Of importance, most of these patients had either abnormal testicular examination results, elevated markers or a history of cryptorchidism. The data suggest that patients with germ cell tumors, even when presenting with cryptic complaints, can readily be diagnosed if a high level of suspicion is maintained, a careful testicular examination is performed and tumor markers obtained. This frequently makes a diagnostic abdominal exploration or other surgical interventions unnecessary.


Assuntos
Germinoma/diagnóstico , Neoplasias Testiculares/diagnóstico , Adolescente , Adulto , Erros de Diagnóstico , Edema/etiologia , Germinoma/complicações , Ginecomastia/etiologia , Humanos , Hipertrofia/etiologia , Perna (Membro) , Pneumopatias/etiologia , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Doenças Neuromusculares/etiologia , Dor/etiologia , Neoplasias Testiculares/complicações
15.
Cancer ; 73(2): 388-93, 1994 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-8293405

RESUMO

BACKGROUND: The rarity of testis tumor in black patients has made the study of a large series difficult. Much of the epidemiologic and clinical information regarding this neoplasm in this population is in dispute, including data on incidence, prognosis, histologic distribution, age and stage at presentation, and side distribution. METHODS: A retrospective review of 66 blacks with testicular tumors from seven military medical centers was performed. RESULTS: Similar results were found for blacks with testis tumor to those of the general testis cancer population regarding prognosis, side distribution, and age of onset for nonseminoma and interstitial tumors. There is a slight increase in the expected number of interstitial tumors in blacks, but the distribution between seminoma and nonseminoma is similar to the general population. The mean age of presentation for seminoma in blacks was younger than that of the general testis cancer population. For testis tumor treated at the same institution, there was an increased delay of diagnosis in blacks compared with whites. The number of new cases of testicular cancer between 1979 and 1991 at one major center was increased for whites but not for blacks. The availability of cisplatin-based combination chemotherapy has resulted in an improved prognosis for blacks, as has already been demonstrated for white populations. CONCLUSIONS: Testis tumor in blacks behaves similarly to testis tumor in the general population except that in blacks there are more interstitial tumors and the mean age of presentation for seminoma is younger. Further, there is an increased delay in diagnosis for blacks compared with whites, but the incidence of this tumor in this population does not appear to be increasing. Cisplatin-based chemotherapy has significantly improved survival in this population.


Assuntos
População Negra , Neoplasias Testiculares/epidemiologia , Adulto , Fatores Etários , Cisplatino/uso terapêutico , Humanos , Tumor de Células de Leydig/epidemiologia , Masculino , Prognóstico , Seminoma/epidemiologia , Tumor de Células de Sertoli/epidemiologia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/tratamento farmacológico , Estados Unidos/epidemiologia
16.
J Urol ; 150(6): 1895-7, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8230529

RESUMO

We report a case of chylo-retroperitoneum and chylothorax following an uneventful left radical nephrectomy for renal cell carcinoma, and propose the mechanism of an infradiaphragmatic lymphatic injury with fistulous connection into the chest. Treatment with oral medium chain triglycerides was unsuccessful. Subsequently, total parenteral nutrition in conjunction with chest drainage, retroperitoneal drainage and sclerotherapy successfully treated the chylothorax. To our knowledge chylothorax following radical nephrectomy has not been reported previously in the literature.


Assuntos
Quilotórax/etiologia , Ascite Quilosa/etiologia , Nefrectomia/efeitos adversos , Idoso , Carcinoma de Células Renais/cirurgia , Tubos Torácicos , Quilotórax/diagnóstico por imagem , Quilotórax/terapia , Ascite Quilosa/diagnóstico por imagem , Ascite Quilosa/terapia , Drenagem , Nutrição Enteral , Feminino , Humanos , Neoplasias Renais/cirurgia , Nutrição Parenteral Total , Tomografia Computadorizada por Raios X
17.
Clin Transplant ; 7(4): 299-301, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-10146299

RESUMO

A retrospective review of the records of 450 patients who were evaluated for renal transplantation was undertaken to determine whether a voiding cystourethrogram (VCUG) influenced the surgical care of the recipient. Three hundred and forty eight of these patients proceeded to transplantation, with 333 of them receiving a VCUG as part of their evaluation. A urologic abnormality was identified by VCUG in 51 individuals, 19 of whom had a known urologic abnormality as the etiology of their renal disease. None of the other 32 patients with abnormalities discovered by VCUG required surgical correction. In the remaining 282 patients the VCUG was normal. The VCUG is not essential for the preparation of potential recipients for renal transplantation and should be utilized selectively in individuals with a history of urologic disease or when urinary tract abnormalities are identified by physical examination or an abnormal urine analysis.


Assuntos
Transplante de Rim/métodos , Urografia , Doenças Urológicas/diagnóstico , Humanos , Cuidados Pré-Operatórios , Urinálise
18.
Brain Res ; 293(2): 313-8, 1984 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-6320971

RESUMO

To relate cerebral oxygen sufficiency and insufficiency with arterial oxygen tension, reduction/oxidation responses of the initial and terminal members of the mitochondrial respiratory chain (NADH and cytochrome c oxidase) were recorded in situ by optical techniques when increased cerebral energy use was provoked by direct electrical stimulation. Small decreases in paO2, produced by forced ventilation of hypoxic gas mixtures, resulted in decreased amplitude of the characteristic negative shift in extracellular potential which accompanies such stimulation and smaller oxidative response of NADH and cytochrome oxidase. When paO2 fell below 40-50 Torr, stimulation produced reductive rather than oxidative shifts of the mitochondrial respiratory chain components. The data suggest that when arterial oxygen tension is slightly decreased, compensating mechanisms allow brain function to continue with minimal changes in cortical metabolites and high energy phosphate compounds. When arterial oxygen falls below 40-50 Torr, however, compensation can no longer prevent tissue hypoxia during times of increased energy demand. Thus, hypoxemia is not necessarily synonymous with oxygen insufficiency, but oxygen sufficiency must be defined with due regard to the degree of energy demand.


Assuntos
Córtex Cerebral/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Hipóxia Encefálica/metabolismo , NAD/metabolismo , Animais , Grupo dos Citocromos a , Citocromos/metabolismo , Estimulação Elétrica , Masculino , Oxirredução , Oxigênio/sangue , Pressão Parcial , Ratos , Ratos Endogâmicos
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