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991.
The endosteal hollow cylinder implant systems have been in clinical use for over 10 years. These systems incorporate advanced sophisticated biomaterials and bioengineering design concepts such as the titanium plasma spray (TPS) surface coating as well as the cylindric shape. This shape has now introduced the third dimension to dental implantology. In previous systems, such as the blade-vent, only height and width were present. Therefore, these previous systems could not be used as single-tooth replacements; also, they were not able to withstand lateral forces or torquing. In a series of cases reported from Switzerland, Sweden, Germany, and the United States, 580 hollow cylinder implants were placed for up to 10 years with an overall rate of success of 95.3 per cent.  相似文献   
992.
A lawsuit directed by parents at a day care program following an outbreak of infectious disease would most likely be based on the legal theory of negligence--the failure to exercise due care as required by circumstances. In the determination of liability for infectious diseases in child day care, the element of causation is most critical. Did the day care facility's actions or failure to act cause the harm? Another important question is whether an infectious disease can be occupational and under what circumstances. Although worker's compensation laws initially had no provisions for occupational disease, now all states recognize responsibility for them. Awareness of potential problems with legal liability and establishment of procedures to minimize risk are important for day care providers, public health officials, clinicians, and parents.  相似文献   
993.
The case reported here demonstrates the importance of considering the possibility of occult malignancy in young patients presenting with extensive or migratory thromboses in atypical locations that appear resistant to standard therapy. Suspicion for malignancy-related thrombosis is heightened by the absence of known precipitating causes and by a negative family history of thrombosis. The search for the responsible underlying neoplasm can be frustrating, but diagnosis and successful treatment of the tumor remain the keys to controlling the abnormal thrombotic state.  相似文献   
994.
995.
996.
We report histological changes in four patients with port wine stains treated with 578 nm yellow light from a high power copper vapour laser. Histology showed that selective damage occurred to the ectatic blood-vessels in the dermis, without haemorrhage and damage to non-vascular structures, and without scarring. The initial damage to the overlying epidermis was not permanent, and the damaged ectatic vessels returned to normal size or were completely necrosed and replaced by collagen.  相似文献   
997.
Indirect evidence suggests that amphetamine (AMPH) releases dopamine (DA) from an extravesicular, cytoplasmic pool. Disruption of vesicular DA storage by reserpine has been hypothesized to increase the concentration of extravesicular DA available for release by AMPH, which is consistent with the observation that reserpine does not prevent but augments the behavioral response to AMPH. In order to more directly test this hypothesis, the in vivo microdialysis technique was used to concurrently examine the behavioral and striatal dopaminergic response to AMPH (1.25 or 2.5 mg/kg) 24 h following reserpine pretreatment (2.5 mg/kg). Reserpine decreased tissue levels of DA by approximately 90% and reduced baseline dialysate DA concentrations by approximately 80%. Reserpine augmented the behavioural effects of AMPH, particularly increasing the occurrence and intensity of stereotypies. In contrast, reserpine did not alter the amount or duration of AMPH-induced DA release. This observation confirms that DA release by AMPH does not depend on vesicular stores but is inconsistent with the hypothesis that augmentation or behaviour by reserpine results from increased striatal DA release.  相似文献   
998.
The authors compared children (ages 7-13 years) of unipolar depressed mothers with children of nondepressed psychiatric patients, of nondepressed medical patients, and of nondepressed mothers in the community. The children's adjustment was rated by clinicians on the Child Adjustment Schedule and by the mothers on the Child Behavior Checklist. The highest proportion of clinically significant problems was found in the children of the depressed mothers. However, the overlap between the problems of these children and those of the children of the nondepressed psychiatric patients calls into question the formulation that children's adjustment difficulties are specific to parental depression.  相似文献   
999.
1000.
Thirty-four epileptic patients, aged 9 to 36, were submitted to A/EEG between May 1987 and July 1988. All patients had a thorough clinical and EEG work-up including long-term conventional EEG, afternoon polygraphic sleep recording and, in some cases, full-night EEG and video monitoring. Patients were divided into 2 groups: group I included 19 patients (18 with symptomatic partial epilepsy (SPE) and 1 with idiopathic generalized epilepsy (IGE) in whom no seizure had ever been recorded in spite of EEG recordings averaging a total of 16 hrs 10 min, awake and asleep); group II included 15 subjects (6 with SPE, 5 with IGE, 3 with symptomatic GE and 1 with undetermined epilepsy) in whom one or several seizures had been recorded. A/EEG was performed in order to: 1) obtain better clinical and EEG characterization of seizures, 2) study the circadian distribution of seizures, 3) verify the efficacy of drug treatment and, 4) establish the epileptic or non-epileptic nature of some ictal events. The results of A/EEG were considered positive in 52.63% of group I patients and in 93.33% of group II patients. The authors discuss the specific advantages of A/EEG vs conventional EEG: recording of seizures with random occurrence, of seizures accompanied by falls, checking the remission of seizures.  相似文献   
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