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941.
Seventy-five Nigerian dentists were interviewed on their approach to the management of impacted third molars. The mean age of the dentists was 34.8 years, with a male/female ratio of 3.4:1. Most of the female dentists were found in the training institutions (p = 0.005). More than half of the dentists (58.7%) practiced in institutions with dental schools (training institutions), majority preferred the buccal approach (92%), and all the dentists (100%) preferred third molar disimpaction under local analgesia. Most dentists (88%) prescribe antibiotics following third molar surgery. Fifty dentists (66.7%) routinely reviewed all patients postoperatively while 12 dentists (16%) were of the opinion that all impacted third molars should be extracted. Only 21 dentists (28%) were aware of any protocol on the management of impacted teeth. More dentists in the training institutions performed third molar surgery less frequently than dentists in other hospitals (p = 0.07) who tend to employ chisels/mallet for bone removal (p = 0.0004). The need for continuing education and the formulation of guidelines in order to assist dentists to make informed decisions is emphasised. This will help conserve scarce resources and enhance the operation of the newly introduced National Health Insurance Scheme.  相似文献   
942.
943.
Background: Smoking is considered to be a risk factor for patients undergoing surgery and anesthesia, but it is unclear whether this is applicable to patients undergoing ambulatory surgery. The aim of this study was to determine the risk of respiratory complications and wound infection among smokers.

Methods: The authors studied a random selection of 489 adult patients undergoing ambulatory surgery. Smoking status was determined by self-report and confirmed with end-expired carbon monoxide analysis. The risk of respiratory complications (i.e., desaturation, cough, laryngospasm, bronchospasm, breath-holding, or apnea) and wound infection (i.e., wound redness or discharge +/- positive microbial culture, requiring antibiotic therapy) in smokers versus nonsmokers was ascertained. Odds ratios were estimated from multivariable logistic regression and adjusted for age, gender, body mass index, partner's smoking status, domiciliary smoking exposure, and extent and duration of surgery.

Results: Most smokers continued to smoke up until the day of surgery. Smokers had a higher rate of respiratory complications (32.8%vs. 25.9%; adjusted odds ratio, 1.71; 95% confidence interval, 1.03-2.84;P = 0.038) and wound infection (3.6%vs. 0.6%; odds ratio, 16.3; 95% confidence interval, 1.58-175;P = 0.019). Odds ratios comparing current plus ex-smokers with nonsmokers were of similar magnitude for most of these complications.  相似文献   

944.
The results obtained by the pharmacological study of alkyl para-cyanophenoxy alkanoates seem to indicate that these derivatives present a sedative effect on the central nervous system. This activity increases with the number of methyl groups substituted, on ethyl para-cyanophenoxy acetate (except the motricity composent), most probably because of an increase in lipophily and therefore in the fixation on the central nervous system.  相似文献   
945.
946.
The temporal changes in childhood and adolescent cancer survival in Sweden 1960-1984 were analyzed. Complete follow-up through 1986 of 6,262 patients younger than 20 years at diagnosis revealed that the overall 5-year survival rates increased from 36.1 to 65.7% in males and from 43.6 to 73.6% in females. The temporal trends differed markedly between age groups and tumour sites and types. Over the study period, 5-years, survival for testicular cancer increased from 46.9 to 87.2%, kidney cancer, predominantly Wilms' tumour from 35.5 to 77.1% (with a higher rate of 89.1% in 1975-1979), Hodgkin's disease from 61.2 to 91.9%, non-Hodgkin's lymphoma from 32.5 to 76.6%, and all leukemias from 8.9 to 58.7%. Only a moderate improvement was noted for tumours of the bone, muscle and connective tissue, and survival rates for tumours of the nervous system remained largely unchanged. Our data reflect the remarkable therapeutic improvements that have occurred for cancer in the young and indicate that these improvements have rapidly become available in Sweden.  相似文献   
947.
948.
The preoperative diagnosis of diffuse heterotopic submucosal cystic malformation of the stomach is very difficult to make with upper gastrointestinal (GI) series or endoscopy. We report a case of submucosal cysts associated with an early gastric carcinoma in which ultrasonography (US) and endoscopic ultrasonography (EUS) were very useful in the preoperative diagnosis.  相似文献   
949.
950.
The dynamics of the speed of transcranial propagation of ultrasonic impulses has been established in humans. The possibility of detecting the changes in mechanical state of intracranial structures by dynamic measurement of the time of transcranial propagation of ultrasonic impulses (TUPT) has been ascertained for 10 healthy persons and 11 patients with different neurological pathology. The cerebrospinal fluid pressure (CSFP) was simultaneously monitored for 4 of the patients. Spontaneous fluctuations in TUPT and the changes caused by jugular veins, inferior vena cava compression, hyperventilation and temporary retention of breathing were detected for all investigated subjects. Spontaneous TUPT changes in the range of 0.25-0.85 x 10(-4) of initial mean value, which are related with cardiac and respiratory cycles, have been found in healthy persons while in patients they ranged from 0.07 x 10(-4) to 4.5 x 10(-4) of mean time. In healthy persons bilateral jugular vein compression leads to a decrease in TUPT by 1.8-3.0 x 10(-4), while the compression of inferior vena cava gives an increase in TUPT by 1.6-2.6 x 10(-4). Changes in TUPT during these maneuvers in neurological patients were found to be of different amplitude and direction. The rise of CSFP by 8.4-20.2 mmHg (mean 12.4 mmHg) was observed in 4 investigated patients during the compression of jugular veins or during the inferior vena cava compression, while the changes in TUPT obtained during each of such maneuvers were of opposite character. The results suggest that dynamic evaluation of acoustic impedance of intracranial system reflects the changes in the mechanical state of brain parenchyma.  相似文献   
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