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661.
662.
Gastric tuberculosis: a manifestation of acquired immunodeficiency syndrome   总被引:1,自引:0,他引:1  
A Haitian man with acquired immunodeficiency syndrome (AIDS), fever, malaise, and diarrhea is described. A computed tomographic (CT) scan showed a retrogastric mass with an associated ulcer. An upper gastrointestinal tract study showed an ulcer with both benign and malignant features. Endoscopy revealed a malignant-appearing ulcer, but cultures and histologic examinations of surgical biopsy specimens indicated gastric tuberculosis. The relationship between tuberculosis and AIDS is discussed.  相似文献   
663.
664.
NONMEM法估算中国癫痫患者苯妥英的群体药动学参数   总被引:9,自引:0,他引:9  
临床上常规收集的161例门诊癫痫患者苯妥英(DPH)的每日剂量—稳态血药浓度数据258对,应用NONMEM程序一步估算其群体药动学参数(meansand、variances),并定量地分析体重、性别、合并用药对最大消除速率Vm(mg·d-1),年龄对米-曼氏常数Km(μg·ml-1)的影响。异性间DPH的Vm无显著差异,群体特征病人(体重60kg,年龄≥15a,未合并用苯巴比妥、安定或硝基安定)的Vm为439mg·d-1,Km为6.21μg·ml-1。体重对Vm的调整值为WT/60的0.57次方,合并用药时Vm增加8.4mg·d-1,年龄<15a则Km下降7%。  相似文献   
665.
Summary— The present work has determined the activities of aromatic L-amino acid decarboxylase (AAAD) and evaluated the presence of an active transport system for dopamine in renal tissues of developing dogs (newborn puppies less than 24 hours after birth, animals at the age of 10 days and 2 months) and adult animals. AAAD activity (Vmax, in pmol/mg protein/h) as determined in kidney homogenates was found to be in the adult dog kidney (Vmax = 3216 ± 268) higher (p < 0.05) than that occurring in the three other groups of animals; no significant difference on AAAD activity was observed between the 10 day-old (Vmax = 1139 ± 185) and the 2 month-old dogs (Vmax = 783 ± 23). AAAD activity in newborn puppies (Vmax = 259 ± 40) was markedly lower than in the three other groups. A considerable amount of the total dopamine formed from added L-DOPA in kidney slices, depending on the age, was found to escape into the incubation medium. The application of the Michaelis-Menten equation to the net transport of newly-formed dopamine has allowed the identification of a saturable (carrier-mediated transfer) and a non-saturable component (diffusion). The Vmax (nmol/g/15 min), Km (μM) values for the saturable component and diffusion constant (μmol?1) were as follows: adult (Vmax = 112 ± 16; Km = 319 ± 35; diffusion constant = 0.0009 ± 0.0001), 2 month-old (Vmax = 19 ± 5; Km = 48 ± 14; diffusion constant = 0.0007 ± 0.0002), 10 day-old (Vmax = 25 ± 3; Km = 69 ± 20; diffusion constant = 0.0033 ± 0.0007) and newborn (Vmax = 6 ± 1; Km = 16 ± 6; diffusion constant = 0.0095 ± 0.0010). In conclusion, renal AAAD develops with age, though some AAAD activity can already be detected at birth. The dopamine outward transporter appears to be considerably immature at birth, but undergoes rapid maturation within the next 10 days; however, development of AAAD and of the renal dopamine outward transporter still proceedes from the age of 2 months until adulthood.  相似文献   
666.
667.
Fifty one infants who were oxygen dependent after treatment for neonatal respiratory disease were entered into a study programme where 100% oxygen was delivered at low flow through a nasal catheter. Thirty five (69%) of the infants were discharged home and the remainder were either discharged to a convalescent hospital or back to their peripheral referring hospital. Excluding repeat admissions for monitoring or for the treatment of acute infections, 2760 hospital days (79 days/patient) were saved, representing a financial saving of $11990 (pounds 6500) per treated infant. A home low flow oxygen therapy programme has benefits to the infant/parent relationship, provides a more constant flow of oxygen than conventional methods, and the early hospital discharge represents a considerable financial saving.  相似文献   
668.
The recent identification of a leukemia-associated inhibitory activity (LIA) against granulocyte-macrophage progenitor cells (CFU-GM) as acidic isoferritins has now led to detection of this activity in normal bone marrow and blood cells. Detection of this activity depends on stimulation of CFU-GM by granulocyte-macrophage colony stimulatory factors (GM-CSF), and some conditioned media (CM) sources of GM-CSF (human placental and monocyte, mouse macrophage and WEHI-3) contained low levels of acidic isoferritin that lowered colony formation. Inactivation or removal of this activity increased the stimulatory capacity of the CM. CM depleted of acidic isoferritins or CM originally devoid of this activity (human GCT, 5637, Mo, lymphocytes: mouse L cells or pokeweed-mitogen-stimulated spleen cells) increased the sensitivity of the assay to detect acidic isoferritin inhibitory activity. This activity was selectively contained and released from normal monocytes and macrophages. Restriction of this activity to mononuclear phagocytes was substantiated, as only continuous cell lines of monocytes and macrophages or lines capable of induction to this lineage contained and released acidic isoferritin inhibitory activity. The cells of origin and target cells of action suggest that acidic isoferritin-inhibitory activity can be considered as a negative feedback regulator, at least in vitro.  相似文献   
669.

Background  

Little is known about how pediatricians or internists manage influenza symptoms. Recent guidelines on antiviral prescribing by the Centers for Disease Control and Prevention (CDC) make almost no distinction between adults and children. Our objective was to describe how pediatricians in two large academic medical institutions manage influenza and compare them to internists.  相似文献   
670.

Background and Purpose

Squamous cell carcinomas of the anal canal are associated with infection with Human Papilloma Viruses (HPVs). Chemo-radiotherapy (CRT) gives 70% 3-year relapse-free survival. Improved predictive markers and therapeutic options are required.

Methods

Tumours from 153 patients treated with radical chemo-radiotherapy (50.4 Gy in 28# with concurrent Mitomycin and 5-Fluorouracil between 2004 and 2009) were retrieved and immunohistochemistry performed for p16INK4A, p53 and EGFR and correlated with outcome. Primary and relapsed samples were analysed for mutations in KRAS.

Results

137/153 (89.5%) stained moderately or strongly for p16INK4A. p16INK4A correlated strongly with outcome. 37/137 patients demonstrating moderate/strong p16INK4A expression relapsed (27.0%), as opposed to 10/16 (62.5%) with absent/weak staining (log rank test p < 0.001). p16 and p53 expression were inversely correlated. p16INK4A negative tumours were more frequent in men. p16INK4A negative patients had significantly worse overall survival (p < 0.001). No mutations in KRAS were identified in primary tumours or relapses following treatment.

Conclusions

p16INK4A is strongly associated with relapse in SCC of the anus and identifies patients with very poor rates of relapse-free and overall survival. Primary and recurrent anal cancer expresses wild type KRAS, unaffected by treatment, supporting trials targeting EGFR in poor risk/recurrent anal cancer.  相似文献   
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