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1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
David Langton Diana Way Lisbeth Trigg Duncan Blake Barry McGrath 《Clinical and experimental pharmacology & physiology》1990,17(3):219-223
1. The effects of graded treadmill exercise on renal blood flow (RBF) were examined in seven rabbits, in which congestive heart failure (CHF) was produced by the administration of doxorubicin, 1 mg/kg, twice weekly for 8 weeks, and in seven controls. A third group of five rabbits underwent doxorubicin treatment with the addition of surgical section of the left renal sympathetic nerve. 2. During submaximal exercise, there was a small reduction in RBF in controls, which was greatly exaggerated in CHF. 3. In both control and heart failure rabbits, there was a precipitous fall in RBF as exercise fatigue developed. 4. Renal sympathectomy ablated these changes in RBF during exercise. 5. It is concluded that in heart failure there is an exaggerated, sympathetically mediated, diversion of blood flow away from the kidney. The onset of exercise fatigue in both normal and heart failure rabbits is accompanied by a marked intensification of this process. 相似文献
3.
4.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
5.
Thoracoscopic esophagomyotomy. Initial experience with a new approach for the treatment of achalasia. 总被引:17,自引:0,他引:17 下载免费PDF全文
C Pellegrini L A Wetter M Patti R Leichter G Mussan T Mori G Bernstein L Way 《Annals of surgery》1992,216(3):291-299
The authors treated 17 patients with achalasia by a thoracoscopic (15 patients) or laparoscopic (2 patients) Heller myotomy. All patients had dysphagia and an upper gastrointestinal series demonstrating a dilated esophagus with a bird-beak deformity at the cardia. Manometry showed a mean lower esophageal sphincter (LES) pressure of 32 +/- 4 mmHg, incomplete sphincter relaxation on swallowing, and no primary esophageal peristalsis. After operation, mean LES pressure was 10 +/- 2 mmHg. Fifteen patients were fed on the second postoperative day. The average hospital stay was 3 days, and there were no deaths or major complications. In three early patients, the myotomy was not carried far enough onto the stomach, and dysphagia persisted until a second myotomy was performed (laparoscopically in two patients). The authors found that having an endoscope in the esophagus during the operation facilitated exposure and was vital to determine the appropriate length of the myotomy. With regard to dysphagia, final results were excellent in 12 patients (70%), good in two patients (12%), fair in two patients (12%), and poor in one patient (6%). Heller myotomy can be safely and reliably performed with minimally invasive techniques. Dysphagia is relieved, postoperative pain is minimal, hospital stay is short, and the patient can return quickly to normal activity. 相似文献
6.
W R Jarnagin Q Y Duh S J Mulvihill J A Ridge T R Schrock L W Way 《Archives of surgery (Chicago, Ill. : 1960)》1992,127(3):261-264
We analyzed 64 percutaneous endoscopic gastrostomy procedures performed by us between 1986 and 1990. Thirty patients had neurologic disease; 16 had head and neck cancers; eight had other malignancies; two had acquired immunodeficiency syndrome; and eight had other problems. Seven patients died within 30 days of complications (n = 4) or the primary illness (n = 3). Mean follow-up was 6 months; an additional patient died of aspiration and eight others died of their underlying illness. There were 19 complications (32%). Four wound complications occurred. Nine patients developed aspiration pneumonia within 3 days of the procedure, four of whom died in the hospital. Of the 24 patients with a history of aspiration, nine experienced aspiration during or after percutaneous endoscopic gastrostomy. Patients with a history of aspiration were more likely to have perioperative aspiration pneumonia, and patients who experienced aspiration were more likely to die. 相似文献
7.
Lygia Stewart J. McLeod Griffiss Gary A. Jarvis Lawrence W. Way 《Journal of gastrointestinal surgery》2007,11(8):977-984
Objective Gallstone bacteria provide a reservoir for biliary infections. Slime production facilitates adherence, whereas β-glucuronidase
and phospholipase generate colonization surface. These factors facilitate gallstone formation, but their influence on infection
severity is unknown.
Methods Two hundred ninety-two patients were studied. Gallstones, bile, and blood (as applicable) were cultured. Bacteria were tested
for β-glucuronidase/phospholipase production and quantitative slime production. Infection severity was correlated with bacterial
factors.
Results Bacteria were present in 43% of cases, 13% with bacteremia. Severe infections correlated directly with β-glucuronidase/phospholipase
(55% with vs 13% without, P < 0.0001), but inversely with slime production (55 vs 8%, slime <75 or >75, P = 0.008). Low slime production and β-glucuronidase/phospholipase production were additive: Severe infections were present
in 76% with both, but 10% with either or none (P < 0.0001). β-Glucuronidase/phospholipase production facilitated bactibilia (86% with vs 62% without, P = 0.03). Slime production was 19 (±8) vs 50 (±10) for bacteria that did or did not cause bacteremia (P = 0.004). No bacteria with slime >75 demonstrated bacteremia.
Conclusions Bacteria-laden gallstones are biofilms whose characteristics influence illness severity. Factors creating colonization surface
(β-glucuronidase/phospholipase) facilitated bacteremia and severe infections; but abundant slime production, while facilitating
colonization, inhibited detachment and cholangiovenous reflux. This shows how properties of the gallstone biofilm determine
the severity of the associated illness.
Presented at the annual meeting of the Society for Surgery of the Alimentary Tract, held May 20–24, 2006 in Los Angeles, California. 相似文献
8.
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses. 相似文献
9.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
10.
Cardiac dysrhythmias are easy. Unlike the lung (which has formidable neuroendocrine, metabolic, and respiratory responsibilities), the heart is simple. It is an innervated muscular pump. A resting Purkinje or ventricular muscle cell membrane maintains a charge of about 90 millivolts. The five phases of a cardiac action potential are similar to the action potential in skeletal muscle, however, the cardiac action potential lasts a hundred times longer. When sodium specific "fast" channels and calcium specific "slow" channels open, positive ions rush into the myocardial cell, thus causing rapid membrane depolarization. In order to produce an action potential, some stimulus must decrease the membrane potential from -90 millivolts to "threshold" or -60 millivolts. Purkinje fibers do not have a stable phase for diastolic potential. These fibers continuously depolarize during diastole. Hypoxemia or hypokalemia may exacerbate this diastolic depolarization, thus promoting "hyperexcitability" or "automatic" ectopy. When myocardium is damaged, characteristically with myocardial ischemia, rapid conduction of cardiac impulses may be slowed dramatically. Very slow impulses may course through muscle such that by the time the activation wave front returns to the initiating site, this origin has had a chance to repolarize. This is the basis for re-entrant dysrhythmias. All cardiac dysrhythmias are automatic, re-entrant or both. 相似文献