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71.
Gallstone ileus is a rare complication of recurrent gallstone cholecystitis and usually occurs in elderly female patients. Recurrent gallstone ileus occurs in 5% of patients with a previous episode of gallstone ileus and is associated with a mortality of 20%. We present a 52-year-old female with recurrent gallstone ileus 1 year after her initial episode. Electronic Publication  相似文献   
72.
Iatrogenic ureteral injuries are an infrequent complication of vascular reconstructive surgery, and if they are not suspected at the time of surgery the diagnosis is usually delayed. Diagnosing these injuries may be challenging, since patients usually show signs and symptoms appropriate to a normal postoperative course and usually do not develop hematuria or renal dysfunction. In the proper clinical setting, a fluid collection adjacent to the ureter on cross-sectional imaging studies should alert the emergency radiologist to the possibility of ureteral injury. A high clinical suspicion would allow earlier diagnosis and treatment, potentially reducing the morbidity and mortality associated with a delay in diagnosis. We present a case of a ureteral leak diagnosed 1 week after an abdominal aortic aneurysm repair. A fluid collection seen adjacent to the ureter on contrast-enhanced CT prompted the radiologist to obtain delayed images that demonstrated urinary extravasation. Electronic Publication  相似文献   
73.
Vertebro basilar insufficiency (VBI) is a well known cause of vertigo. Brain Single Photon Emission Computed Tomography (SPECT) is an important diagnostic tool to detect and to quantitate the perfusion abnormalities in different areas of the brain. Effect of an antivertigo drug Betahistine on improving the hypoperfusion in different areas of the brain in vertigo patients was studied using brain SPECT. Betahistine at a dose of 16 mg three times daily was shown to improve perfusion in the hypoperfused areas of the brain resulting in relief from symptoms of vertigo. The cerebellar region, which is the most important area involved in vertigo patients with vascular pathology, showed almost complete normalisation of perfusion following Betahistine therapy.  相似文献   
74.
BACKGROUND: Currently the most important limitation in lung transplantation is donor availability. Although liberalization of donor criteria may aid in expanding the donor pool, the long-term effects of the use of "marginal" or "extended" donors remains unexplored. METHODS: In this study, we included all patients who underwent lung transplantation from January 1996 to December 1999 at Loyola University Medical Center. We categorized patients as either receiving lungs from an "ideal" donor or an "extended" donor. Extended donors were defined as having any 1 of the following criteria: donor age > 55 years, tobacco history > 20 pack years, presence of infiltrate on chest x-ray, donor ventilator time > 5 days, or donor use of inhaled drugs (cocaine or marijuana). We then compared the 2 groups with regard to short-term (operating room [OR] complications, intensive care unit [ICU] complications) and long-term outcomes (1-year pulmonary function and survival). RESULTS: Sixty-one (54%) patients received lungs from ideal donors and 52 (46%) patients received lungs from extended donors as defined above. We observed no significant differences between the 2 groups in OR complications (cardiopulmonary bypass, bleeding complications, life-threatening arrhythmias) or ICU complications (pneumonia, airway dehiscence, reoperation within 30 days related to transplantation). In addition, the 2 groups had similar median intubation times (21 hours in the ideal donor group and 20 hours in the extended donor group; p = n.s.), hospital length of stay (14+/-12 days in the ideal donor group and 12+/-8 days in the extended donor group; p = n.s.), and hospital survival (80% and 88% in the ideal and extended donor groups, respectively). One-year follow-up revealed similar pulmonary function (forced expiratory volume in 1 sec [FEV(1)] = 2.4 liters and 2.4 liters in the recipients of bilateral ideal and extended donors, respectively, and FEV(1) = 1.9 liters and 1.5 liters in the recipients of single ideal and extended donors) and survival (72% and 79% in the ideal and extended donor groups, respectively; p = n.s.) between the 2 groups. CONCLUSIONS: Liberalization of donor criteria does not affect outcome in the first year after lung transplantation. By liberalizing donor criteria, we can expand the donor pool while assessing other possible mechanisms to increase donor availability.  相似文献   
75.
Bifunctional chelates offer a general approach for the linking of radioactive metal cations to macromolecules. In the specific case of 99mTc, a variety of technologies have been developed for assembling a metal-chelate-biomolecule complex. An evaluation of these methodologies requires an appreciation of the coordination characteristics and preferences of the technetium core structures and oxidation states, which serve as platforms for the development of the imaging agent. Three technologies, namely, the MAG3-based bifunctional chelates, the N-oxysuccinimidylhydrazino-nicotinamide system and the recently described single amino acid chelates for the {Tc(CO)3}1+ core, are discussed in terms of the fundamental coordination chemistry of the technetium core structures. In assessing the advantages and disadvantages of these technologies, we conclude that the single amino acid analogue chelates (SAAC), which are readily conjugated to small peptides by solid-phase synthesis methods and which form robust complexes with the {Tc(CO)3}1+ core, offer an effective alternative to the previously described methods.  相似文献   
76.
Angiomyolipoma is a distinctive neoplasm composed of an intimate admixture of three components, viz. mature adipocytes, smooth muscle cells and blood vessels. This study was undertaken to better define the various morphological patterns of angiomyolipoma and their immunohistochemical profile. The paraffin blocks and slides of 18 cases of renal angiomyolipoma, accessioned over a period of 8 years from Tata Memorial Hospital, were reviewed. There were 2 men and 16 women in the age range of 17 to 68 years. Pre-operative fine needle aspiration cytology (FNAC) was performed in 6 cases, of which 5 were erroneously diagnosed as renal cell carcinomal sarcoma. Histologically, 14 cases revealed conventional histology. The remaining 4 cases were particularly misleading posing diagnostic problems due to variant patterns (leiomyomatous variant-3 cases and epithelioid variant- 1 case). Apart from the usual histology, necrosis, giant cells, and varying degrees of nuclear pleomorphism were present in three of the cases. Immunohistochemistry performed in 16 cases revealed immunoreactivity for HMB45 in all the 16 tumors (100%), estrogen receptor (ER) and progesterone receptor ((PR) in 2 cases (12.5%) and 6 cases (37.5%) respectively.  相似文献   
77.
The authors report a case of skeletal myopathy in a four-year-old boy on long-term sodium valproate therapy for secondary epilepsy due to neurocysticercosis. He presented with clinical features of limb girdle weakness. EMG revealed features of myopathy. Carnitine deficiency due to sodium valproate was suspected and plasma carnitine levels were found to be low. Sodium valproate was withdrawn. L-carnitine supplementation resulted in marked clinical recovery as well as rise in plasma carnitine levels.  相似文献   
78.
79.
Based on the results of independent studies the involvement of norepinephrine in REM sleep regulation was known. Isolated studies showed that the effect could be mediated through either one or more subtypes of adrenoceptors. Earlier we have reported that REM-OFF neurons continue firing during REM sleep deprivation and mild but continuous stimulation of locus coeruleus (LC) or picrotoxin injection into the LC, that did not allow the REM-OFF neurons in the LC to stop firing, reduced REM sleep. However, the mechanism of action and type of adrenoreceptors involved in REM sleep regulation were unknown. The possible mechanism of action has been investigated in this study. It was proposed that if LC stimulation-induced decrease in REM sleep was due to norepinephrine, adrenergic antagonist must prevent the effect. Therefore, in this study, the effects of alpha1, alpha2 and beta-antagonists, viz. prazosin, yohimbine and propranolol, respectively, and alpha2 agonist, clonidine, on LC stimulation-induced reduction in REM sleep were investigated. The results showed that stimulation of LC inhibited REM sleep by reducing the frequency of generation of REM sleep, although the duration per episode remained unaffected. This decrease in the frequency of REM sleep was blocked by beta-antagonist propranolol while the duration of REM sleep per episode was blocked by alpha1-antagonist, prazosin. Also, a critical level of norepinephrine in the system was required for the generation of REM sleep, however, a higher level may be inhibitory. Based on the results of this study and our earlier studies, an interaction between neurons, containing different neurotransmitters and their subtypes of receptors for LC-mediated regulation of REM sleep has been proposed.  相似文献   
80.
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