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X G Liu

Publications and source records attributed to X G Liu.

48 records · Page 3Linked to original sources
PubMed1989

[Clinical application of CT stereotactic device in biopsy of brain lesions].

A new CT stereotactic device named version WL-86 was designed and manufactured by the authors. Phantom puncture and cadaver puncture tests showed that its accuracy is less than 1 mm. We have also made a new type of biopsy needle--the rotary and translational cutting biopsy needle. A definite pathological diagnosis was made in 93.7% (30/32) of patients by this technique: The practicability of the device, the indications and clinical value of CT-guided stereotactic biopsy were discussed.

Adolescent↗
PubMed1982

Genetics of cleft lip and cleft palate in China.

During the past 10 years, 60 cases of cleft lip with or without cleft palate [CL(P)] were recorded among 45,072 newborns at Shanghai International Peace Maternity and Infant Hospital, China. The incidence was 1.33 per 1,000 births. The family histories of 163 CL(P) patients were analyzed. The incidences of CL(P) in the first-, second-, and third-degree relatives of CL(P) patients were 11/246 (4.47%), 10/1,032 (0.97%), and 6/1,727 (0.35%), respectively. Of the 163 probands, three had a history of consanguinity of the parents (1.8%), in contrast to 0.77% in the general population. These data are suggestive of multifactorial inheritance. The heritability of CL(P) in our study calculated by Falconer's formula was 77.6%.

Adult↗
PubMedDate not supplied

Nonfluoroscopic reduction of intussusception by air enema.

Intussusception is a common pediatric condition in China. Hydrostatic reduction with barium sulfate or pneumatic reduction using air and fluoroscopy has become the standard method in most centers throughout the world. To avoid radiation exposure, reduction without fluoroscopic confirmation was studied. Between 1981 and 1985 a total of 224 children were diagnosed and treated for intussusception. The diagnosis was made correctly on clinical grounds in 184 cases; in 40 cases ultrasonography confirmed the clinical diagnosis. Pressurized air reduction was successful in 217 patients (96.9%); seven patients required operative reduction. Ultrasonograms of the abdomen supported the diagnosis in 40 patients and confirmed subsequent reduction. This experience demonstrates that childhood intussusception can be reduced using pneumatic pressure without exposing the patient to ionizing radiation.

Air↗
PubMedDate not supplied

Induction of hepatic and presystemic metabolism of antipyrine in the mice: rifampicin versus rifabutin.

The effects of hepatic and presystemic enzyme induction on the bioavailability (F) and disposition of antipyrine after repeated rifampicin (RFM) and rifabutin (RBT) exposure were studied in mice. ICR mice were divided to receive 4 daily oral dosing of either the dosing vehicle or 50 mg/kg of REM or RBT. At the completion of rifamycin dosing, the pharmacokinetics of antipyrine were assessed following either a single 50 mg/kg oral dose or a 20 mg/kg intravenous dose. Blood samples were collected (n=4/timepoint) over a 6 h period. The content of P450 in the liver and small intestine (GI) was also assessed in parallel. Systemic antipyrine clearance (CL) increased from 31.8 ml/min/kg (controls) by 64% and 42% following repeated exposure to RFM and RBT, respectively. Estimate of F for antipyrine decreased from 0.97 in controls to 0.58 and 0.82 in animals treated with RFM and RBT, respectively. The content of P450 (nmol/mg protein) in the liver increased from 0.61 (control) to 1.36 following RFM and 0.82 for RBT, while no significant changes were observed for the GI tract. The i.v. dosing data confirmed the induction of antipyrine metabolism in the liver by both rifamycins yet the induction potential was approximately 1/3 lower for RBT. This difference was consistent with the changes observed in the hepatic P450 protein content, but this alone could not account for the reduction in the F for antipyrine. Therefore, predictions for changes in F of an interacting agent should not be judged solely on the basis of the metabolic status of the liver. The relative contribution of metabolic induction and presystemic drug loss to bioavailability/absorption should also be further delineated for its relevance to poly-pharmacy in patients likely to receive long-term rifamycin based treatment.

Administration, Oral↗
PubMedDate not supplied

Prognostic and biological role of neurotrophin-receptor TrkA and TrkB in neuroblastoma.

Expression of different neurotrophin receptors of the tyrosine kinase (Trk) family plays an important role in the biology and clinical behavior of neuroblastomas (NB). Observations from several independent studies suggest that high expression of TrkA is present in NB with favorable biological features and highly correlated with patient survival, whereas TrkB is mainly expressed on unfavorable, aggressive NB with MYCN-amplification. To determine expression of Trk receptors and ligands in primary NB, we developed a reliable semiquantitative duplex RT-PCR protocol, that requires only 1 microgram RNA per tumor sample. Activation of TrkA by its ligand nerve growth factor (NGF) initiates a cascade of signaling events and promotes neuronal differentiation in vitro. Activation of TrkB by its ligand brain derived neurotrophic factor (BDNF) has been associated with proliferation and survival of NB cells. To study Trk signal transduction pathways and their biological effects in NB, we stably expressed TrkA and TrkB cDNA in the human NB cell line SH-SY5Y. Introduction of TrkA and TrkB restored responsiveness of SH-SY5Y cells to the ligands NGF and BDNF, respectively, and resulted in morphological differentiation. Expression of TrkA resulted in growth inhibition of the transfectants compared to parental cells, whereas TrkB transfectants demonstrated an increased proliferation rate. Further insight into the differences of TrkA and TrkB signaling may suggest new options for the treatment of NB. As expression of TrkA is a strong prognostic factor especially in MYCN non-amplified NB, a prospective study of Trk receptor expression using RT-PCR should be performed for German neuroblastoma patients.

Biomarkers, Tumor↗