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Biomedical subjects

R H Zhao

Publications and source records attributed to R H Zhao.

6 recordsLinked to original sources
PubMed2001

[A new method for predicting retention time of solutes under linear gradient elution conditions in RP-HPLC].

A new method for predicting the retention time of solutes under linear gradient elution has been established. In this method, the migration distance of solutes in column and the mobile phase gradient were modified simultaneously according to the distribution of mobile phase in column. The prediction results of retention time of both weakly and strongly retentive solutes were accurate in different instrumental systems using this method. In order to test and verify this method, the retention time of fifteen amino acids and eight homologous compounds of benzene were predicted. The predicted results were compared with those predicted by the method in common use. The relative average errors between predicted and experimental values were 3.70% and 4.90% for the weakly retentive solutes, far smaller than those obtained by the reference method (23.61% and 31.16%). For the strongly retentive solutes, the relative average errors were 0.21% and 6.01% respectively, slightly smaller than those obtained by the reference method (0.81% and 6.69%). It is seen that this new method has many advantages.

Amino Acids↗
PubMed2000

Simple rectovaginal fistulas.

In regard to the causes of simple rectovaginal fistulas (RVF) we examined the methods of diagnosis and the efficacy and outcome of surgical procedures. The study included all of our patients diagnosed with simple RVF between December 1988 and July 1998 (n = 19). Medical charts of these patients were reviewed regarding diagnostic investigations, operative procedure, outcome, and follow-up. The most common cause was obstetric trauma (n = 15, 79%) followed by infection (n = 4, 21%). Eight patients (42%) had undergone anal surgery prior to the development of RVF; two of these had undergone more than one procedure. Endoanal ultrasound was performed in 15 patients and identified the fistula in 11 (73%). A concomitant sphincter injury was visualized in 9 of 15 patients (60%). The most common initial operation performed was an endoanal advancement flap in 12 patients (63%). This operation was performed in combination with a sphincteroplasty in 4 patients, while 3 had sphincteroplasty alone. The mean hospital stay was 3 days (range 1-5). Postoperative morbidity was noted in 5 patients (26%) of and consisted of recurrent fistula and passage of gas per vagina. Surgery was successful in complete resolution of symptoms in 14 cases (74%). Two of the three recurrences were successfully repaired with a repeat endoanal advancement flap, and one is awaiting repair. The mean follow-up for the entire group was 35.8 months (range 6-84). Endoanal advancement flap should be the initial treatment of choice for simple, low rectovaginal fistulas. The procedure can also be employed with expectations of success even after a failed primary repair and should be combined with sphincteroplasty if a coexistent anteriorly based anal sphincter defect is noted either by clinical examination or endoanal ultrasonography.

Adult↗
PubMed2000

Sleep and periodic limb movement in sleep in juvenile fibromyalgia.

OBJECTIVES: Fibromyalgia has been recently recognized in children and adolescents as juvenile fibromyalgia (JF). In adult fibromyalgia, subjective complaints of nonrestorative sleep and fatigue are supported by altered polysomnographic findings including a primary sleep disorder known as periodic limb movements in sleep (PLMS) in some subjects. Although poor sleep is a diagnostic criterion for JF, few reports in the literature have evaluated specific sleep disturbances. Our objectives were to evaluate in a controlled study the polysomnographic findings of children and adolescents with JF for alterations in sleep architecture as well as possible PLMS not previously noted in this age group. METHODS: Sixteen consecutive children and adolescents (15.0 +/- 2.6 years of age) diagnosed with JF underwent overnight polysomnography. Polysomnography was also performed on 14 controls (14.0 +/- 2.2 years of age) with no history of an underlying medical condition that could impact on sleep architecture. Respiratory variables, sleep stages, and limb movements were measured during sleep in all subjects. RESULTS: JF subjects differed significantly from controls in sleep architecture. JF subjects presented with prolonged sleep latency, shortened total sleep time, decreased sleep efficiency, and increased wakefulness during sleep. In addition, JF subjects exhibited excessive movement activity during sleep. Six of the JF subjects (38%) were noted to have an abnormally elevated PLMS index (>5/hour), indicating PLMS in these subjects. CONCLUSION: Our study demonstrated abnormalities in sleep architecture in children with JF. We also noted PLMS in a significant number of subjects. This has not been reported previously in children with this disorder. We recommend that children who are evaluated for JF undergo polysomnography including PLMS assessment. juvenile fibromyalgia; periodic limb movement in sleep; restless legs syndrome.

Adolescent↗
PubMed1996

[Clinical research of the bushen tiaojing decotion in promoting ovulation].

A comparative study on effect of promoting ovulation between Bushen Tiaojing Decoction (BSTJD) and clomifene was conducted. Results showed that the ovulation rate of BSTJD group was 66.67%, as compared with that of clomifene group (61.54%), the difference was insignificant (P > 0.05), However, there was a significant difference (P < 0.05) between the two groups in effective rate of menoxenia treatment (82.14% versus 66.67%). No toxicity or side-effect appeared. These results suggested the BSTJD could definitely promote the ovulation, and has a good effect in treating menoxenia and improving the symptoms. The mechanism of BSTJD might be regulating the function of hypothalamus-pituitary-ovary system to promote ovulation.

Adult↗
PubMedDate not supplied

High performance liquid chromatographic determination of individual bile acids in serum for automatic diagnosis of various liver and biliary diseases.

A reversed phase high performance liquid chromatographic method for the high sensitivity determination of individual bile acids in serum using a C18 column with a ternary solvent system combined with fluorometric techniques using immobilized enzymes is described. A computer-assisted diagnosis system using pattern recognition was developed to assist the clinical diagnosis of various liver and biliary diseases. A total consistency rate of 95% can be reached using this system.

Acetonitriles↗