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1.
Camphor and m-cresol mixtures are used in antiseptic and anti-itching creams. No compendial method exists for these preparations. This paper reports a capillary gas chromatographic method using FID detection with 2,6-di-tert-butyl-4-methylphenol as internal standard on a 30 m×0.32 mm Supelcowax®-10 column (0.25 μm film) with helium as carrier gas. Ramped temperature programming was applied. The method allows simultaneous quantitation of camphor and m-cresol in the presence of o- and p-cresols, calamine and zinc oxide. Overall percent recoveries (±SD, n=9) of camphor, o-, p- and m-cresol from spiked placebo creams, at a labeled amount of 10 (w/w)% were 96.9±0.6, 98.2±0.6, 99.2±0.5 and 101.0±0.9%, respectively, and at a labeled amount of 1% were 96.7±0.6, 97.8±0.9, 97.8±0.6, and 100.3±1.0%, respectively. The recovery studies were carried out at ±30% of the labeled amounts. Linear peak area or height ratios were obtained (r>0.999) for camphor, o-, p- and m-cresol covering a concentration range of 10–200% of the labeled amount. Linearity (r>0.999) was also obtained for m-cresol when the relative concentration of o- and p-cresol was varied from 5 to 100% of the m-cresol concentration. The resolution between the ‘critical pair’ of p- and m-cresol was ≥1.1. The limit of quantitation was 23 pg for m-cresol and 9.3 pg for camphor using an injection split of 1:50. The repeatability (%RSD) for all compounds were <2% for peak area and <1.4% for peak height ratios. System suitability and robustness of the method were established. The method was successively applied to the assay of available commercial products and allows assay of camphor and the three cresol isomers.  相似文献   
2.
The epsilon-sarcoglycan gene (SGCE) on human chromosome 7q21 has been reported to be a major locus for inherited myoclonus-dystonia. Linkage to the SGCE locus has been detected in the majority of families tested, and mutations in the coding region have been found recently in families with autosomal dominant myoclonus-dystonia. To evaluate the relevance of SGCE in myoclonus-dystonia, we sequenced the entire coding region of the epsilon-sarcoglycan gene in 16 patients with either sporadic or familial myoclonus-dystonia. No mutations were found. This study suggests that epsilon-sarcoglycan does not play an important role in sporadic myoclonus-dystonia and supports genetic heterogeneity in familial cases.  相似文献   
3.
BACKGROUND: Wall-motion analysis during low-dose dobutamine echocardiography (LDDE) is a semiquantitative measure of left ventricular contractile reserve after myocardial infarction (MI). The Doppler echocardiographic myocardial performance index (MPI) is a quantitative measure of combined left ventricular systolic and diastolic function. We sought to characterize the changes in MPI during LDDE in control subjects and patients with MI, and to describe the relation of these changes to changes in regional systolic function. METHODS: MPI was obtained at rest and during LDDE (10 microg/kg/min) in 25 healthy volunteers (group 1) and 50 patients with a recent MI. Patients were divided into two subsets; those with (n = 23; group 2A) and those without (n = 27; group 2B) a contractile reserve defined as an improvement of wall motion in more than two contiguous infarct-zone segments during LDDE. DeltaMPI was defined as the change from rest to LDDE. RESULTS: MPI decreased significantly during LDDE in groups 1 and 2A, whereas MPI increased in group 2B (DeltaMPI = 0.12 +/- 0.04 and 0.10 +/- 0.08 vs -0.03 +/- 0.08, P <.0001). On multivariate analysis, Deltawall-motion score index predicted DeltaMPI (beta = 0.65, P <.0001) independently of age, sex, and the dobutamine-induced change in heart rate and systolic blood pressure. CONCLUSIONS: Data suggest that the change in MPI during LDDE may provide a simple and quantitative measure of overall left ventricular functional reserve in patients with a recent MI.  相似文献   
4.
OBJECTIVE--To identify prognostic factors in a consecutive series of patients with bleeding oesophageal varices and develop an optimum regimen of treatment. DESIGN--Retrospective review. SETTING--I Department of Surgery, University Hospital, Vienna, Austria. PATIENTS--301 consecutive patients with bleeding oesophageal varices. OUTCOME MEASURES--Median survival and survival at one year after sclerotherapy alone (n = 213), or sclerotherapy with portosystemic shunt (n = 54), Hassab's devascularisation (n = 29), or liver transplantation (n = 5). RESULTS--Prognosis was dependent on the severity of liver damage at the start of treatment. Median survival for Child's class A was 47 months, for Child's class B 54 months, and for Child's class C 2 months. The overall one year survival for patients in Child's class C was 33%, for sclerotherapy alone 28%, and for sclerotherapy and portosystemic shunt 42%, Hassab's devascularisation 50%, and liver transplantation 80%. CONCLUSION--Despite the small number of patients who underwent liver transplantation and their poor initial prognosis (Child's class C, n = 4; class B, n = 1) our results suggest that liver transplantation should be considered for the treatment of patients with end stage cirrhosis and bleeding varices.  相似文献   
5.
In previous decades, infants who received blood transfusions shortly after birth or in utero might have been infected at a particularly vulnerable age by some blood-borne oncogen it virus. A cohort of such infants has therefore been followed into adult life to see if they suffered any excess of neoplastic disease or of non-neoplastic mortality. A total of 12,690 infants were identified who were transfused between 1 January 1942 and 31 December 1970, in most cases for the prevention or treatment of haemolytic disease of the newborn. All but 361 (2.8%) were found to have been registered with a National Health Service (NHS) practitioner and were followed in the NHS central records until they died, emigrated, were removed from NHS lists or until 1 January 1992, whichever occurred first. Mortality and cancer incidence were compared with that expected from national rates. No marked disparity was observed and there was no excess of childhood leukaemia. The incidence of non-Hodgkin's lymphoma at 15 to 49 years of age was about twice that expected, but the excess was not statistically significant.  相似文献   
6.
The clinico-pathological features of nine urethral and urinary bladder polyps with prostate-type epithelium are described. The average age of the patients was 46 years. Three patients previously had cystoscopy and the lesion was not noticed on the initial examination. The commonest presentation in this series was haematuria, dysuria and frequency of micturition. One patient presented with postmicturition dribble and another with haemospermia. The polyps contained acini and papillae lined by prostate-type epithelium which was confirmed by immunohistochemical tests for prostate specific antigen and prostate acid phosphatase. In this series no age versus location relationship could be established. Symptoms resolved following resection or initial biopsy followed by fulguration. Recurrence is extremely rare.  相似文献   
7.
Six of 12 children with Down syndrome (DS) tested by means of long-term tape-recordings of oxygen saturation, breathing movements and expired CO2 were found to have previously undetected and severe upper airway obstruction during sleep. In five cases the obstruction occurred in the pharynx and in the sixth it was due to bilateral choanal stenosis. When compared with age-matched controls, overnight tape-recordings showed episodes of abnormal arterial hypoxaemia and an abnormally elevated end-tidal CO2. Episodes of obstruction were most marked during sleep associated with a non-regular breathing pattern. Abnormal episodes of hypoxaemia were associated with continued breathing movements. Sometimes there was no airflow (complete obstruction); at other times airflow continued normally or was reduced in amplitude (partial obstruction). During episodes of partial or complete airway obstruction the inspiratory waveform showed a characteristic shape. These results show sleep-related upper airway obstruction to be an often undetected complication of DS and all necessary measures should be taken to overcome the obstruction when it reaches the stage of producing abnormal hypoxaemia. Choanal dilatation and tracheostomy were successful in treating two of the children. Tonsillectomy and adenoidectomy were successful for one child, but only of marginal benefit for two others.  相似文献   
8.
BACKGROUND: Abnormalities in the limbic-hypothalamic-pituitary-adrenal (LHPA) axis have been implicated in the pathogenesis of obsessive-compulsive disorder (OCD). To our knowledge, however, no prior study has measured pituitary gland volume in OCD. METHODS: Volumetric magnetic resonance imaging studies were conducted in 31 psychotropic drug-na?ve children (10 boys, 21 girls) aged 8-17 years and 31 case-matched healthy comparison subjects. RESULTS: Pituitary volume was significantly smaller in patients with OCD as compared with healthy control subjects (11% smaller). Smaller pituitary volume in patients with OCD was associated with increased compulsive but not obsessive symptom severity. Boys with OCD had smaller pituitary gland volumes compared with control boys (20% smaller). No significant differences in pituitary volume were observed between girls with OCD and control girls. Boys with OCD had significantly smaller pituitary volumes than girls with OCD (31% smaller), whereas control boys also had smaller pituitary gland volumes compared with control girls (21% smaller). CONCLUSIONS: These findings provide new evidence of reduced pituitary volume in pediatric OCD that seems to be more prominent in male patients. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the LHPA axis in OCD.  相似文献   
9.
The clinical aspects of peritonitis and catheter infections were reviewed in 64 children on continuous ambulatory peritoneal dialysis living in Saudi Arabia over a period of 6 years. Peritonitis occurred in 41 children (64%). The mean time from starting dialysis to the first episode of peritonitis was 7.2 months. The incidence of peritonitis was 1 episode in 9 treatment months. Gram-negative organisms were responsible for the majority of episodes (42%), followed by Gram-positive organisms (20%), and Candida albicans (6%); 32% were culture negative. Recurrent peritonitis was present in 20 cases. Catheter was replaced in 24 patients: 44% due to recurrent peritonitis. Peritoneal membrane loss occurred in 7 patients, 3 had Candida peritonitis and 3 had recurrent peritonitis due to Pseudomonas. The mortality rate was 4.6% but none of the deaths were related to peritonitis or dialysis. Received August 23, 1995; received in revised form October 2, 1996; accepted October 18, 1996  相似文献   
10.
This study reports an opinion survey of 211 nonpsychiatrist physicians in two general hospitals who estimated that 16.1% of their patients have psychiatric disorders and that they spent 13.8% of their time in treating the psychiatric components of their patients' illnesses. Physicians indicated that anxiety and psychosomatic and depressive illness were the most frequent psychiatric disorders and that one-third of them would personally treat such disorders without referral to psychiatric consultation. The findings also suggest that adequate undergraduate psychiatric education was associated with increased recognition of psychiatric disorders and more preference for their personal treatment. In addition, it provides a possible explanation for the discrepancy between the high prevalence of psychiatric disorders in general hospital patients and the low referral rate to psychiatric consultation.  相似文献   
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