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81.
82.
This study examined ethnic differences in the levels of inpatient admission and outpatient attendance in Great Britain using the latest national data available from the General Household Surveys of 1983-87. Inpatient admissions in immigrants (Indian, Pakistani and West Indian) did not differ significantly from whites, except for a marked excess in Pakistani women of childbearing ages. The pattern was quite different for outpatient attendance, with immigrant children and young adults having lower attendance rates than whites, and middle-aged immigrant adults showing higher rates. Levels of hospital-based care among immigrant groups may be lower than expected. As monitoring of the health status of ethnic groups, and their use of services, receives increasing recognition, it is important that information on ethnic origin is included in routine health information systems.  相似文献   
83.
A new method, termed reprojection, is used to visualize anatomic morphology contained within three-dimensional reconstructions made up of images of multiple parallel cross sections. This method involves the projection, either orthographically into a plane or radially onto a cylinder, of the volume picture elements (voxels) of the reconstruction. Orthographic reprojection images, formed by mathematically summing the magnitudes of the voxels along selected parallel paths through the reconstructed volume, are analagous to conventional radiographs formed by the passage of an X-ray beam through the volume. The reprojection image is a two-dimensional array of picture elements that is displayed on a television monitor using a digital-to-video scan converter. Also described are the techniques of noninvasive selective tissue dissolution and numerical dissection, whereby obscuring portions of the reconstructed volume are either partially "dissolved" or totally eliminated before reprojection. Utilizing these methods, anatomic information present in a three-dimensional reconstruction but not clearly seen in a reprojection image is rendered visible after removal of superposed structures. The usefulness of these methods is demonstrated utilizing three-dimensional reconstructions of the thorax, heart, and coronary arteries of dogs.  相似文献   
84.
Our preliminary studies suggested that the novel gag-truncated mos (tmos) open reading frame (ORF) of R7, a spontaneous deletion mutant of Moloney murine sarcoma virus 124 (MoMuSV124), may be responsible for R7's unique ability to induce brain lesions in all R7-injected mice. However, when we replaced the gag-tmos ORF with either the MoMuSV124 or the homologous myeloproliferative sarcoma virus env-mos gene, we found that both recombinant viruses also induced brain lesions in all injected mice. Although these studies suggested that the critical determinants for brain lesion induction may reside in the tmos sequence common to all three viruses, they did not demonstrate if the N-terminus of Mos was dispensable for this activity. By inserting the FLAG sequence at the 3' end of the R7 gag-tmos ORF, we demonstrated that R7 does synthesize a Gag-tMos fusion protein. Using R7 gag deletion mutants with and without the FLAG sequence, we further demonstrated that (i) deletion of the entire gag sequence abolished R7's transforming activity; (ii) the ability of the virus to transform cultured NIH/3T3 cells was significantly reduced only when most of gag was deleted; (iii) the ability of the virus to induce brain lesions was inversely proportional to the extent of its gag deletions; and (iv) the insertion of FLAG at the Mos C-terminus did not reduce the in vitro transforming activity of the FLAG-tagged viruses but did reduce their ability to induce brain lesions. Thus, we have demonstrated that altering the N- or C-terminus of the R7 Gag-tMos fusion protein can affect disease manifestation.  相似文献   
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86.
Olanzapine has previously been shown to have predominant metabolism by cytochrome (CYP) P450 1A2. Caffeine has been shown to provide an accurate phenotypic probe for measuring CYP1A2 activity. The purpose of this study is to determine if a significant correlation exists between olanzapine disposition and caffeine metabolic ratios. Subjects were phenotyped for CYP1A2 activity with caffeine probe methodology. After 200-mg caffeine administration, blood (4 h), saliva (6 and 10 h), and urine (8 h total) were collected for high-performance liquid chromatography (HPLC) analysis of caffeine and its metabolites.CYP1A2 activity was measured as plasma (PMR(4 h)), saliva (SMR(6 h) and SMR(10 h)), and three urinary metabolic (UMR1(8 h), UMR2(8 h), and UMR3(8 h)) ratios. Each of the 14 healthy nonsmokers (13 male) received a single 10 mg olanzapine dose after which blood was collected for HPLC determination of olanzapine concentrations at predose and at 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 6, 8, 10, 12, 24, 48, 72, 96, and 120 h postdose. Olanzapine pharmacokinetic parameters in this study were similar to those previously published. All caffeine metabolic ratios (PMR(4 h), SMR(6 h), SMR(10 h), UMR1(8 h), and UMR2(8 h)) significantly correlated with each other (p <0.001) except for UMR3(8 h), which did not correlate. A significant correlation (p <0.05) was also found between olanzapine clearance and PMR(4 h) (r=0.701), SMR(6 h) (r=0.644), SMR(10 h) (r=0.701), UMR1(8 h) (r=0.745), and UMR2(8 h) (r=0.710). A negative correlation was observed between olanzapine clearance and UMR3(8 h) (r=-0.029, p=NS). A significant correlation was found between olanzapine clearance and various caffeine metabolic ratios. Interpatient variability in CYP1A2 activity may explain the wide interpatient variability in olanzapine disposition. Compounds that modulate CYP1A2 activity may be expected to alter olanzapine pharmacokinetics accordingly.  相似文献   
87.
Primary T-cell lymphoma of the gastrointestinal tract is a rare and usually aggressive disorder that may be associated with celiac disease. The authors describe a unique case of a clonal proliferation of CD8+ T cells involving the oral mucosa, ileum, and colon of a 35-year-old man that has regressed spontaneously and recurred numerous times over a 9-year period without treatment. The patient's symptoms were limited to occasional rectal bleeding and recurring painful oral ulcers. Within the intestine, these collections of small T cells induced minimal architectural distortions and did not show extensive epitheliotrophism. Polymerase chain reaction and sequencing analyses revealed that the identical T-cell clone has been present for more than 9 years and in different mucosal locations in this patient. This may represent a unique T-cell lymphoproliferative process akin to a mucosal counterpart of lymphomatoid papulosis of the skin.  相似文献   
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89.
EDITORIAL COMMENT: In medicine, human judgment is fallible, but obstetrics is the discipline in which an error of judgment is most rapidly revealed, to the obstetrician, the patient and the labour ward staff, due to the unpredictability of the duration of labour and imminence of delivery in any individual patient. When the editor was a house officer he was called to the antenatal ward because a multipara, near term had abdominal pain. Vaginal examination revealed an undiluted cervix, but within the minute or so it took a walk to the handbasin to wash his hands the woman had delivered a live baby into the bed. It is always wise, and should be a routine. unless operating in haste for an emergency such as bleeding from placenta praevia, to perform a vaginal examination after anaesthesia is established before commencing Caesarean section in a woman in labour. The editor has performed many safe easy-forceps deliveries in this circumstance, in theatre, in women in whom Caesarean section was planned for cephalopelvic disproportion with or without fetal distress. This finesse is more important if the consultant has agreed to perform a Caesarean on the findings recorded by others, but the fact remains that labour and delivery can accelerate most unexpectedly. We accepted this case report for publication, not merely because it is the first such case reported, but also for the opportunity it provided to stress to readers the need for final evaluation of the stage of labour before Caesarean section, when the conditions are most favourable for assessment. Nonetheless, as this case tells us. it is possible for labour and delivery to proceed faster than the obstetrician can perform a Caesarean section.  相似文献   
90.
头颈外科包括了头颈部肿瘤及相关疾病的诊断和治疗。香港头颈外科的起源可以追述到本世纪60年代中期。当时的香港大学玛丽医院外科学系主任王源美教授是开创这一领域的先驱。香港最初只有普外科医生涉及到这一区域肿瘤的治疗,经过多年来其它专科的发展,目前香港头颈部的疾病已经可以由三个外科次级专科处理,即耳鼻喉科、整形重建科和普外科。20年来,在外科、放射科及化疗科的共同努力下,头颈部肿瘤在诊断及治疗方面获得的迅速的发展,这就使病人的预后得到了很大程度的改善。  相似文献   
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