Biomedical subjects

S Li

Publications and source records attributed to S Li.

At least 901 records · Page 50Linked to original sources

PubMed1998

[Radioimmunoassay of substance P in human hypertrophic scar].

OBJECTIVE: To measure the content of substance P in human hypertrophic scar. METHOD: The method of radioimmunoassay was used to determine the content of substance P in human hypertrophic scar, non-hypertrophic scar and normal skin. RESULT: The content of substance P in hypertrophic scar was significantly higher than that in non-hypertrophic scar and normal skin (P < 0.01). CONCLUSION: Substance P may play an important role in the process of hypertrophic scar development.

Adolescent↗

PubMed1998

[The flag venous flap in the dorsal finger].

OBJECTIVE: To improve the design and application of the flag flap. METHOD: Based on the anatomical characteristics of the dorsal digital veins and the venous arch, the flag flap pedicled with the veins in the dorsum of the finger was used to repair the skin defects of the ventral finger and hand in six cases. RESULTS: All flaps survived with primary healing. Three months' follow-up showed that the function and appearance of the finger were satisfactory. CONCLUSION: The design of the flap broadens its application in repairing the defects on the ventral finger and hand.

Adolescent↗

PubMed1998

The caries-inhibiting effect of a fluoride drop program: a 3-year study on Chinese kindergarten children.

OBJECTIVE: To evaluate the caries-inhibiting effect of a fluoride drops program in two kindergartens in Chengdu, Sichuan Province, a fluoride-deficient area. METHODS: For 3 years, participating children ingested in school 0.25 mg fluoride daily, in the form of drops for 2 to 3-year-olds and 0.5 mg for children age 3 years and older. These systemic fluoride supplements were made available for over 180 days each year and they were distributed by teachers who maintained attendance records. Annual examinations were conducted for 176 2-year-olds who had used the supplements in the kindergartens and 148 control children. After 3 years, 128 test and 112 control children remained in the study. RESULTS: The results demonstrated a marked reduction in dental caries in the control group: test children had 2.21 decayed, missing, or filled teeth (DMFT)-versus 4.32 in the control group, a reduction rate of 48.84%. The mean DMFT increments over the 3-year period were 1.76 and 3.92, respectively. Over a 1- to 3-year period of supplement use, the group provided with the fluoride drops had consistently lower caries prevalence than the control group. The differences were statistically significant. CONCLUSIONS: This treatment regimen demonstrated an effective caries-inhibiting effect.

Cariostatic Agents↗

PubMed1998

[Experimental study on denervated skeletal muscle autotransplantation in the rhesus monkey].

OBJECTIVE: This study was to provide a scientific basis for clinical application of denervated muscle transplantation. METHODS: A rhesus monkey was used in this experiment. The denervated extensor digitorum brevis (EDB) and the extensor hallucis brevis (EHB) of the rhesus monkey were autotransplanted in the sacrospinal muscle, and they were biopsied at intervals and stained with HE, Bielshowsky and enzyme. The specimen were examined with light and electro-microscope. RESULTS: The metabolism of the denervated muscle was lower than the normal. There was muscle regeneration and growing nerve fibers in the graft 12 weeks after transplantation. CONCLUSION: Denervated muscle can regenerate in oxygen-deficient environment. If the denervated muscle is in contact with normal muscle, the nerve of the recipient muscle will grow into the graft.

Animals↗

PubMed1998

[Application of the free parascapular flap in children].

OBJECTIVE: To improve surgical results we have applied the free parascapular flap in children for facial or cervical burn scar contracture. METHOD: Eight children aged from 6 to 9 years received free flap transfer. Based on the defect and the distribution of the cutaneous branches of the circumflex scapular vessels, the flap was designed with its size ranging from 15 cm x 8 cm to 22 cm x 6.5 cm. RESULT: Free flap transferring with microvascular anastomosis was successful in all cases. The average operation time was 5 hours with average blood loss being about 100 ml. CONCLUSION: Free flap transplantation is safe and beneficial in children when the technique and skill of microsurgery and plastic and reconstructive surgery are mastered and intraoperative blood loss is controlled under 1% of the total blood volume. The vertically oriented parascapular flap can not only provide proper tissue for reconstraction but also minimise the donor site morbidity.

Burns↗

PubMed1998

[Detection and enrichment of fetal cells in maternal circulation for prenatal diagnosis of fetal sex].

OBJECTIVE: To study fetal cells from maternal peripheral blood for prenatal diagnosis of fetal sex. METHODS: Samples of peripheral blood in 64 women of 8-40 gestational weeks were collected to enrich the fetal nucleated red blood cells by density gradient centrifugation. DNA was extracted from each samples of enriched fetal cell for PCR amplification of Y chromosome specific DNA to determine fetal sex. RESULTS: Fetal nucleated red cells were found in 25 out of 64 maternal samples (39.06%). Y chromosome 149 bp was found in 28 cases of the 33 mothers given birth to male babies. One Y specific DNA sequence was detected in 31 women had female babies. The sensitivity was 84.85% and specificity 96.77%. The overall agreement of the diagnosis was 90.63%. CONCLUSION: Density gradient centrifugation can enrich fetal nucleated red blood cells from maternal peripheral blood. Fetal sex can be determined by PCR amplification of Y chromosome specific DNA with these fetal cells.

Blood Circulation↗

PubMed1998

[A rapid simple and reliable method for sequencing the targeted gene of shuttle vector pSP189].

The authors established a simple, rapid and effective procedures for sequencing the targeted a-gene SupF TRNA of shuttle vector pSP189, which is very important and useful in molecular mechanism research of mutagens. In this method, double-stranded plasmid DNA as template, prepared single-stranded DNA with alkali denaturation, applied r-32P-ATP for labelling 5'-end of primer, were used. A satisfactory result was achieved.

Escherichia coli↗

PubMed1998

[Emergency measures on drinking water sanitation for mitigation of flood and waterlogging disasters].

This article reports the emergency measures for mitigation during flood and waterlogging disasters to ensure drinking water sanitation and to prevent infectious disease outbreaks. Five preparatory and preventive measures for flood and waterlogging disasters include the construction of dual-purpose water supply installation for ordinary and disaster use, the storage of qualified technicians and materials (or their inventories), and the formulation of predetermination programme for disaster relief, ect.

China↗

PubMed1998

[Effects of mifepristone on ICE expression and Fas expression in early pregnant chorionic villi].

This study addressed the question whether mifepristone has any effect on apoptosis in early pregnant chorionic villi. Interleukin 1 beta converting enzyme(ICE) expression and Fas expression in early pregnant villi and their changes following mifepristone administration were detected by immunohistochmical method and computer image analysis. During early pregnancy, ICE and Fas were expressed in all component chorionic cells, predominantly syncytiotrophoblasts. ICE stained cytoplasma. Fas stained mainly cytoplasma, and in partial trophoblastic cells, Fas was expressed on membrane and nucleus. In the villi from the pregnant women who received mifepristone for 2 days, expression of Fas increased markely; the ratio of positive nuclear staining cells were significantly raised, but the immunostaining intensity of ICE was slightly increased. These results suggest that mifepristone may terminate early pregnancy via increasing the expression of Fas and promoting apoptosis in the chorionic villi.

Abortifacient Agents, Steroidal↗

PubMed1998

[Immunoprotection in guinea pigs using DNA recombinant plasmid rpDJt and expressed protein P68 in L. interrogans serovar lai].

Immunoprotection against the infection by Leptospira interrogans serogroup Icterohemorrhagiae serovar lai strain 017 was demonstrated in guinea pigs vaccinated with DNA recombinant plasmid rpDJt and expressed protein P68 derived from genomic library of Leptospira strain 017. Thirty days after active immunization, each group received intraperitoneally (1/2 dose) and subcutaneously (1/2 dose) inoculum of L. interrogans serovar lai stain 017; cultures were adjusted to 5 x 10(8) cells/ml. All guinea pigs were observed for 10 days after challenge. Survival (%) of P68 group was 100(7/7); P23 group was 75(3/4); group rpDJt was 77(10/13); group lack recombinant (control) pT7-7 was 25 (3/12), and group with whole-cell inactivated vaccine was 93(13/14). Although the protective antigen in the leptospires has yet to be determined, it is evident that expressed protein P68 conferred a high degree of immunoprotection in guinea pigs.

Animals↗

PubMed1998

[A comparison study on the sensitivity of lung tumor short-term induction test in three strains of mice].

To compare the sensitivities of lung tumor short-term induction in different strains of mice, the carcinogenicity risk was evaluated with the incidence rate and the average number of tumors. Three different strains of mice (KM, BALB/c and A/J) were injected with a single different dose of urethane i.p. The results demonstrated that the lowest dose for increasing tumor risk was 100 mg/kg in KM, 200 mg/kg in BALB/c, and lower than 25 mg/kg in A/J strain. So, the sensitivity of A/J strain is the highest and that of BALB/c is the lowest.

Animals↗

PubMed1998

[Nucleotide sequence analysis of a species specific probe by an inserted fragment from recombinant plasmid pCX7 of L. interrogans sensu stricto serovar lai].

The etiological agents of leptospirosis are the pathogenic leptospires (L. interrogans sensu lato) which can be divided into 223 serovars organized into 23 serogroups. The serovar remains the basic taxon, but serotyping may now be accomplished and recognized by acceptable methods. Complementary molecular approaches are being used extensively to assess genetic relatedness amongst leptospires with restriction endonuclese analysis (REA), pulse field gel electrophoresis (PFGE) and DNA-DNA hybridization as well established tools. However, the method is cumbersome and unsuitable for routine application. To develop a sensitive and specific method for identification of pathogenic leptospires, a genomic library of L. interrogans sensu stricto serovar lai was constructed with the plasmid vector pUC9. A recombinant plasmid, designated pCX7 which has homologous fragment of pathogenic leptospires was screened from the bank. pCX7 could recognize pathogenic leptospiral DNA fragment 1.7 kb of strain 017 without cross hybridization to nonpathogenic leptospiral DNA. Inserted fragment of pCX7 DNA sequencing was performed by Dr. Yan Zhengxin (Max-Plank-Institut fur Biology, Tubingen, Germany). Insert fragment was cloned into pBluescript and sequenced by using ABI(Applied Bio. Systems, Model 373A). Nucleotide sequences were analyzed by Dr. Xiao Jianguo (Texas University Medical School and School of Public Health, Center for Infectious Diseases) using a suit of computer program (NIH). One open reading frame of 306 nucleotids were identified. There were identifiable initiation codons, terminators, pribnow box and sextama box within the sequenced regions. These results further confirmed that the little homology between L. interrogans sensu strito and L. borgpeterseni serovar javanica, L. inadai serovar ranarun and serovar manhao (L. genomospecies 2), L. biflexa serovar patoc, L. illini. pCX7 DNA probe could provide a base for identification and classification of leptospires.

DNA, Bacterial↗

PubMed1998

[Cloning, characterization and expression in E. coli of the flagellin gene from Leptospira interrogans Serovar lai].

To obtain a large amount of recombinant endoflagellin protein of leptospsira, we have cloned the fla B gene from Leptospira interrogans serovar lai strain 017, which encodes the core flagellar protein. The entire open reading frame was amplified by polymerase chain reaction, which was digested with endonucleases Sal I and Cla I, then was orientationally cloned into the expression vector, pT7-7. The recombinant plasmid was transformed into Escherichia coli JM109 (DE3) for expression. After induction with IPTG, a 34 kd expression protein was detected by SDS-PAGE. The amount of recombinant protein was estimated as 11.8% of the whole bacterial lysate proteins. Probed with insert fragments, Southern blot analysis indicated that possibly two gene related to fla B were present in the genome of Leptospira interrogans serovar lai stain 017. Western blot analysis showed that the 34 kd expression protein reacting with rabbit polyclonal antiserum raised against leptospira endflagellin.

Cloning, Molecular↗

PubMed1998

[Expression of endothelial nitric oxide synthase gene in placental villus of preeclampsia].

OBJECTIVE: To investigate the expression of endothelia nitric oxide synthase (eNOS) mRNA in the villus of preeclampsia and the relationship between eNOS and preeclampsia. METHODS: Dot blot, using DIG-labeled human eNOS cDNA probe, had been used to examine the expression of eNOS gene in placental tissues of 9 normotensive pregnancy and 9 preeclampsia women. By using Leica QWIN image disposal and analysis system Mean OD of every dot was assessed. RESULTS: The level of eNOS mRNA in placental villus was significantly lower in preeclampsia woman than that of control group (P < 0.001). CONCLUSION: The decrease of eNOS in placental villus of preeclampsia may be one of the causes for human placental dysfunction and high impedance of fetoplacental circulation in preeclampsia. It may play an improtant role in the genesis of pregnancy induced hypertension.

Adult↗

PubMed1998

[Complications of endoscopic sinus surgery: incidence and prevention-analysis of 307 cases].

The complications of endoscopic sinus surgery performed on 307 patients with chronic inflammatory paranasal sinus diseases were analysed. The results showed that: 1. The common complications were excessive bleeding, orbit penetration, intra-orbital haemorrhage, postoperative stenosis of the maxillary ostium and middle turbinate adhesions. 2. The most common perioperative complications were those related to orbital penetration except excessive bleeding. A major complication was a case of cerebrospinal rhinorrhea with secondary purulent meningitis. 3. The annual overall incidences and the rates of common complications have been significantly decreased with year. The causes and prevention of excessive bleeding, stenosis of maxillary ostium and middle turbinate adhesions are discussed emphatically. In addition, the proposals were offered concerning the diagnostic criteria of the complications, and the statistical method of the complication incidence.

Adolescent↗

PubMed1998

[Feasibility study of laser-induced fluorescence (LIF) spectrum for diagnosis of colon cancer].

OBJECTIVE: To study the usefulness of laser-induced fluorescence (LIF) spectrum for diagnosis of colon cancer. METHODS: Nitrogen laser, wavelength 337 nm, optical multichannel analyzer (OMA III) were used to demonstrate LIF spectra. A standard spectrum of LIF of colon cancer was used to analyse that of 51 surgically removed colon specimens and the results were compared with pathological findings. RESULTS: Compared with pathological findings, LIF spectrum examination had 80.0% sensitivity, 100% specificity, with positive predictive value of 100%, negative predictive value of 83.9% and accuracy of 90.2% for the diagnosis of colon cancer, respectively. CONCLUSION: Laser-induced fluorescence (LIF) spectrum of colon is of use in the diagnosis of colon cancer.

Colonic Neoplasms↗

PubMed1998

[Thallium poisoning a clinical analysis of 5 cases].

OBJECTIVE: To sumarize the clinical features, diagnosis and treatment of thallium poisoning by analysis of clinical cases. METHODS: Five cases of thallium poisoning were reported. The clinical manifestations, quantitative-analysed thallium level, methods and effect of treatment, and prognosis were analysed. RESULTS: Three of the 5 cases were acute, and the other two chronic. Four of them had a history of poison contact. The clinical features included alopicia (4 cases), transverse white stripes in the nails (Mee's stripes, 2) polyneuropathy, cranial nerve and central nervous system impairments (5), and abdominal pain and other digestion disturbances (3). All of the 5 cases were treated with antidotes and other methods to increase thallium excretion. One case died of lung infection 3 days after diagnosis. The serum and urine thallium levels of the 4 survivors decreased to normal after treatment (3 recovered, one had neurologic sequelae). CONCLUSION: It is not difficult to diagnose thallium poisoning by definite poison contact history, classical manifestation, and serum or urine thallium quantitative analysis. Attention should be paid to those patients with indefinite exposure to thallium. For those suspected cases, it is necessary to measure the thallium level in blood and urine in order to verify the diagnosis.

Adult↗

PubMed1998

Extended frontotemporal epidural approach to cavernous sinus: surgical anatomy and technique.

OBJECTIVE: To investigate the surgical technique of trans-frontotemporal extended epidural approach to the cavernous sinus. METHODS: A microsurgical study on the exposure and dissection of the cavernous sinus and its surrounding structures on cadavers was performed via an extended epidural approach with frontotemporal skull-base craniectomy. RESULTS: The extended epidural approach offered an appropriate exposure of the cavernous sinus with minimal brain retraction and nerve damage. CONCLUSIONS: The extended frontotemporal epidural surgical approach is superior to the routine intradural or combined epi- and intradural approaches. It is suitable for most of the cavernous sinus surgeries.

Brain Neoplasms↗