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991.
Mohamed J. Hejase John P. Donohue Richard S. Foster Richard Bihrle Christopher L. Coogan Randall G. Rowland Gregory R. Wahle 《The Journal of urology》1996,156(4):1345-1348
Purpose
We determined if the behavior of germ cell tumors metastatic to the mediastinum is different from that of primary mediastinal germ cell tumors, a group known to have distinct clinical features.Materials and Methods
A search of the computerized data base for germ cell tumors metastatic to the mediastinum at our university revealed 80 patients, 65 of whom underwent concomitant retroperitoneal lymph node dissection at mediastinal surgery.Results
Of the patients 60 (75 percent) are free of disease, 14 (18 percent) died of cancer and 6 (8 percent) are living with disease. Mediastinal pathology included teratoma in 65 percent of the patients, cancer in 26 percent and fibrosis in 9 percent. Of the 65 patients who underwent retroperitoneal lymph node dissection 75 percent had teratoma, 15 percent had fibrosis and 10 percent had cancer. Mediastinal relapses after dissection were rare (4 of 80 patients).Conclusions
Germ cell tumors metastatic to the mediastinum appear to behave similarly to those metastatic to the retroperitoneum. Primary mediastinal germ cell tumors have an entirely different clinical course. Teratoma is the predominant pathological type of post-chemotherapy germ cell cancer metastatic to the mediastinum. 相似文献992.
Robert Dreicer David M. Gustin William A. See Richard D. Williams 《The Journal of urology》1996,156(5):1606-1608
Purpose
We evaluated the role of paclitaxel in patients with advanced urothelial carcinoma and renal insufficiency or as second line therapy for metastatic disease.Materials and Methods
Nine patients with advanced urothelial carcinoma received 175 to 250 mg./m.2 paclitaxel intravenously as a 24-hour infusion. Six patients had renal insufficiency with a median serum creatinine of 2.25 mg./dl. (range 1.9 to 3.2) and 3 with normal renal function were treated after disease progression following 1 to 2 prior chemotherapy regimens.Results
Of 9 patients 5 (56 percent) achieved a partial response, including 4 to 6 with renal insufficiency. Toxicity was primarily hematological with 4 patients experiencing febrile neutropenia. There was no adverse impact on renal function.Conclusions
Paclitaxel as a single agent represents an effective therapeutic alternative for patients with advanced transitional cell carcinoma of the urothelium and renal insufficiency precluding cisplatin or gallium nitrate based chemotherapy. Additionally, paclitaxel appears to be effective in patients in whom prior cisplatin based therapy failed. 相似文献993.
John F. Ward Michael Nowacki John P. Sands Richard J. Conner Thomas K. Huisman 《The Journal of urology》1996,156(4):1381-1385
Purpose
Local recurrence of prostate cancer following complete and successful resection of organ confined disease has been variably reported in men. We hypothesized that observed secretions from the cut distal urethra during radical prostatectomy may contain malignant prostatic epithelial cells and contribute to this problem.Materials and Methods
A prospective study was done of prostate cytology specimens from 50 consecutive men with clinically organ confined adenocarcinoma of the prostate undergoing radical retropubic or radical perineal prostatectomy. Direct cytological evaluation by 1 examiner was used to identify malignant or benign cells in these washings.Results
Of 33 radical perineal and 17 radical retropubic prostatectomy specimens organ confinement was confirmed in 58 percent. Malignant prostatic epithelial cells were observed in 24 percent of all cytology specimens. Of cytological washings from prostates with pathologically confirmed organ confined cancers 17 percent showed malignant cells. While perineural invasion was noted in a majority of tumors with positive washings, only Gleason grade was a statistically significant predictor of recurrence (p = 0.009). Surgical approach did not alter the rate of positive cytology.Conclusions
Malignant prostatic epithelial cells can be identified in the prostatic washings from men with pathologically organ confined prostate cancer. Surgical approach did not change the cytological findings. Gleason grade is a statistically significant predictor of cytological malignancy. These cells may represent a mechanism of failure following successful radical prostatectomy. 相似文献994.
Objectives
To compare safety and efficacy of fascial versus vaginal wall slings in the management of women with intrinsic sphincter deficiency (ISD).Methods
The hospital and office records of 79 consecutive women with ISD were retrospectively analyzed from January 1991 to September 1995. There were 43 fascial slings (group A) and 36 vaginal wall slings (group B). Parameter of evaluation included efficacy based on postoperative presence of stress or urge incontinence and number of pads used, complications, and miscellaneous factors, including length of catheterization time, length of hospitalization, quantity of analgesics used, and loss of work days.Results
Baseline clinical and urodynamic data were the same for both groups. Pad use decreased from 6.9 to 0.6 for group A and from 5.7 to 0.3 for group B. Persistent stress and urge incontinence was present in 5% and 16% of group A patients and in 3% and 11 % of group B patients, respectively. Group A (89%) and group B (94%) patients were either very satisfied or satisfied with their surgical outcome. The operative time, hospital days, and days lost from work for group B patients (42.3 ± 13.4 minutes, 1.4 ± 0.9 days, 18.4 ±3.2 days, respectively) were significantly lower than for group A patients (84.2 ± 17.8 minutes, 3.7 ± 1.9 days, 28.4 ±7.8 days, respectively).Conclusions
Both fascial and vaginal wall slings are effective in treating women with ISD. However, the use of vaginal wall slings resulted in significantly shorter hospital stay, decreased catheterization time, decreased use of analgesics, and decreased loss of days of work compared with fascial slings. Therefore, the vaginal wall sling should be the preferred surgical method of treating intrinsic sphincter deficiency. 相似文献995.
996.
Richard M. Wahba 《Journal canadien d'anesthésie》1996,43(11):1144-1149
Purpose
The literature describing the pulmonary mechanisms of increasedPA-PaO2 during general anaesthesia was examined to define the role of airway closure and sub-radiological atelectasis.Source
A Medline search was designed to include articles dealing with the stated purpose, which is thus selective rather than a meta-analysis. The MeSH consisted of the following words: Anesthesia: general / inhalational; Pulmonary gas exchange; Ventilation.perfusion ratio; Lung Physiology; Lung Volume measurements; Closing Volume/Capacity; Functional Residual Capacity; Atelectasis; Diaphragm. Also, Dr H. Rothen and Prof. G. Hedenstierna supplied raw data.Principal findings
Changes in shape and dimensions of the thorax and abdomen immediately after induction of anaesthesia result in marked alterations in the efficiency of oxygenation. Three pathways can be described: increased effects of airway closure, increased low ventilation: perfusion in dependent lung zones, and frank atelectasis. The magnitude of the alterations is determined by the patients’ age and body habitus. Some of the changes may carry-over into the postoperative period. The data suggest that increasing tidal volume during anaesthesia will reduce the effects of airway closure and that vital capacity breaths will re-expand atelectatic areas.Conclusion
Airway closure and atelectasis contribute equally to the increased ventilation: perfusion mismatching that occurs during general anaesthesia. 相似文献997.
Richard W. M. Wahba Michael J. Tessler Simcha J. Kleiman 《Journal canadien d'anesthésie》1996,43(1):77-83
Purpose
This article examines and summarizes the published reports dealing with subcutaneous emphysema, pneumothorax and carbon dioxide (CO2) embolism during laparoscopic upper abdominal surgery. The purpose is to describe the expected clinical picture, the differential diagnosis and the management of these complications.Source
The information was obtained from a Medline literature search and the annual meeting supplements of Anesthesiology, Anesth Analg, Br J Anaesth and Can J Anaesth.Principal findings
An abrupt increase in PetCO2 is the first sign of subcutaneous emphysema and of pneumothorax. Desaturation and increased airway pressure occur with pneumothorax, but not with subcutaneous emphysema alone. Desaturation and increased airway pressure also occur with bronchial intubation. The preliminary diagnosis is made by verifying the position of the tube, examination of the patient for swelling and crepitus and auscultation for air entry. Chest radiography and paracentesis confirm the diagnosis of pneumothorax, which frequently occurs with subcutaneous emphysema but is rarely of the tension type. Pulmonary embolism due to CO2 during WAS has not been reported, but the available data suggest that small, haemodynamically inconsequential CO2 embolism occurs without change in PetCO2. Massive embolism is possible and will markedly decrease PetCO2, arterial O2 saturation (SpO2) and blood pressure.Conclusion
The immediate recognition of the three complications requires continuous monitoring of PetCO2, arterial saturation, airway pressure, and an index of pulmonary compliance. 相似文献998.
Dr. Gerard M. Doherty MD H. Richard Alexander MD Maria J. Merino MD David J. Venzon PhD Jeffrey A. Norton MD 《Annals of surgical oncology》1996,3(2):198-203
Background: The anticancer role of tumor necrosis factor-alpha (TNF-) has been limited by toxicity. These experiments evaluate blocking endogenous interferon-gamma (IFN-) activity to abrogate TNF- toxicity.
Methods: C57Bl/6 mice bearing MCA 105 tumor were treated with TNF- and anti-IFN- antibody (Ab) to evaluate the effect on the acute lethality of TNF- and their efficacy as evaluated by tumor growth rate, tumor histology, and survival.
Results: Anti-IFN- Ab decreased TNF- lethality. Anti-IFN- Ab alone increased tumor growth significantly more than did nonimmune IgG (p2<0.0001). Tumor-bearing mice that received nonimmune IgG and TNF- had slower tumor growth (p2<0.02) and a trend toward improved survival (p=0.07) compared with saline-treated controls. Anti-IFN- Ab abrogated the antitumor effect of TNF-, prevented acute tumor necrosis histologically, and resulted in tumor growth rate and host survival similar to that of controls. The findings in mice that received anti-IFN- Ab and high-dose TNF- were comparable with those in mice that received a lower, equitoxic dose of TNF- alone.
Conclusions: Blocking endogenous IFN- accelerates tumor growth in this model and partially abrogates the toxic and antitumor activity of exogenous TNF- equally. This suggests that blocking endogenous IFN- activity is not a useful strategy for limiting TNF- treatment toxicity.Presented in part at the 45th Annual Cancer Symposium of The Society of Surgical Oncology, New York, New York, March 15–18, 1992. 相似文献
999.
Paul M. Gross Richard J. Beninger Steven W. Shaver Dan S. Wainman Francisco J. Espinosa Donald F. Weaver 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,95(3):397-408
The neuroactive peptide endothelin-1 has receptors distributed abundantly among subdivisions and nuclei of the visuovestibular and oculomotor systems. In previous work, we and others described the convulsive manifestations resulting from central injection of this neuropeptide, including nystagmus, oculoclonus, exophthalmos, tonic hindlimb extension, and a generalized repetitive motor disturbance called barrel-rolling. We applied the quantitative, autoradiographic [14C]deoxy-glucose method to examine the hypothesis that visuovestibular and oculomotor structures would become metabolically stimulated when endothelin was introduced into the brain via the ventricular system in conscious rats. Since previous work had demonstrated that hypermetabolic responses to endothelin in other neural systems were inhibited by an antagonist of neuronal calcium L-type channels, nimodipine, we further tested whether the increased function of vestibulooculomotor nuclei whose metabolic activity was sensitive to endothelin could be altered following nimodipine pretreatment via the ventricle. A single unilateral injection of endothelin (9 pmol in 3 l saline) into a lateral ventricle provoked significantly increased rates of glucose metabolism in 22 of 39 individual anatomical structures of the visuovestibular and oculomotor systems. Among those affected were the superficial stratum of the caudal superior colliculus (+25%), the optic tract bilaterally (+ 35 to 43%), the oculomotor cranial nerve nuclei (III, IV, VI; range of +21 to 47%), and the medial terminal nucleus of the accessory optic tract which harbors dense fields of endothelin binding sites (bilateral increase of +70 to 96%). Several other nuclei involved in the proprioceptive and visuovestibular disturbance caused by endothelin displayed increased metabolic activity, including the cuneate, gracile, sensory trigeminal, and prepositus hypoglossal nuclei, the vestibular subnuclear system, and the cerebellar flocculus. Identification of hypermetabolic responsivity to endothelin in these structures provides further information on the anatomical substrates mediating the behavioral phenomenology of endothelin-induced motor convulsions which involve the paroxysmal participation of the extraocular muscles and motor control systems producing barrel-rolling convulsions. Nimodipine pretreatment inhibited both the convulsive activity and the cerebral hypermetabolic responses to intraventricular endothelin. The results indicate that the neural systems sensitive to intraventricular endothelin become functionally active via a calcium-mediated process that may involve the neuropeptide as an intrinsic signaling molecule. 相似文献
1000.