Biomedical subjects
Publications and source records attributed to W Li.
The foramen arcuale of vertebral artery of altas is one of the causes of vertigo. Leven cases of the cervical vertigo caused by foramen arcuale were operated on. The patients were followed up for 3-6 years. The results were satisfactory. The mechanism of inducing vertigo by foramen arcuale was discussed. We demonstrated that excision of the foramen arcuale is available for cervical vertigo.
A prospective study of excimer laser photorefractive keratectomy (PRK) was performed with the aim of correcting a range of myopic errors between -1.00 and -10.00 diopters on 422 myopic eyes that were followed for more than one year. At postoperative one year, 91.4% of the eyes had uncorrected visual acuity of 20/20 or better, and 97.4% were within +/- 1.00 diopter of the desired emmetropia, and the corneal haze disappeared in most of the eyes. Elevated intraocular pressures were observed in 20.4% of the eyes. The decrease of one line of the best corrected visual acuity occurred in 7.6% and of two lines in 0.5% of the eyes. We think that the excimer laser PRK is a very predictable, safe, stable, and effective method to correct myopia up to -10.00 D, and longer follow-up will be necessary.
Three-dimensional (3D-) reconstruction of intravascular ultrasound (IVUS) images is a recently introduced technical method which has rapidly grown in science and clinical practice. In the catheterization laboratory it is particularly important to obtain the 3D-reconstruction on-line, since the dimensions measured and the plaque attributes displayed may guide the therapeutic decision. Off-line reconstruction, however, provides very accurate and reproducible area and volume measurements of lumen and plaque and is thus exceptionally qualified for studying progression/regression of atherosclerosis or restenosis after catheter-based interventions. Complementary 3D-reconstruction methods, revealing specific advantages and limitations, meet the requirements by slightly different technical approaches, but each 3D-reconstruction of two-dimensional IVUS images requires some basic procedural steps. The IVUS images can be acquired during continuous or ECG-gated withdrawals of the IVUS imaging catheter. The latter permits even to visualize the cyclic pulsation of the reconstructed arteries. As an alternative approach a sensing device recognizes the insertion depth of the IVUS catheter and permits reliable measurements even during manual handling of the IVUS catheter. A discrimination between the blood-pool and structures of the vascular wall, performed in the digitized images, can be achieved by the application of different techniques. This processing step which is called segmentation and the image acquisition are particularly crucial with regards to the final quality of the 3D-reconstruction. Currently there are still limitations of 3D-IVUS, but a new approach combining data obtained from 3D-IVUS and biplane angiography offers a promising potential to solve most of the remaining problems in the future. Thus, three-dimensional IVUS offers a great clinical and scientific potential since it provides spatial visualization of vascular pathology, longitudinal and volumetric measurement of luminal and plaque dimensions, and facilitated guidance of catheter-based interventions. Assuming a technical development similar to the progress of the previous years. 3D-IVUS has a realistic chance to gain significant importance and to become a routine technique in the future.
Motility of gastric strips taken from different regions of guinea pig stomach were simultaneously recorded in 8 tissue chambers to test the effect of cholecystokinin-octapeptide (CCK-8) and secretin. It was found that CCK-8 could increase (1) all regional circular and longitudinal muscular tension at rest, (2) the frequency of contractions in body, antrum and pylorus, (3) the mean contractile amplitude of antral circular strips, (4) the motility index of pylorus, but decrease the mean contractile amplitude of body and antral longitudinal strips. All the CCK-8 effects could not be blocked by atropine or indomethacin. Secretin was without effect on gastric smooth muscle activity.
A total of 750 six-month follow-up records of myopia treated with excimer laser photorefractive keratectomy (PRK) were analyzed. By 6 months, in group 1 (up to -6.00D, 587 eyes), uncorrected visual acuity was improved to 20/20 or better in 86.7% of treated eyes and 95.4% fell into the range of refraction of +/- 1.00D. In group 2 (-6.25D to -11.00D, 163 eyes), 74.5% of treated eyes had uncorrected visual acuity of 20/20 or better and 89.4% of the eyes were within +/- 1.00D. The designed predictability of the two groups was the same (P > 0.1). The refractive stability from 3 to 6 months between the two groups was not statistically different, and no severe complications were observed in these two groups. The excimer laser PRK for correcting myopia up to -11.00D appears to be effective, predictable, stable and safe in this study. The ideal outcome may result from the precise ablation quality of excimer laser, its computerized surgical manipulation and an appropriate postoperative management including detection of refractive indices by corneal topography and modulation by steroid.
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From 1988 to 1991, 17 patients with malignant periacetabular tumors underwent limb-sparing surgery and reconstruction using the saddle prosthesis. There were 8 patients with primary malignant lesions (Group 1), and 9 patients with metastatic or systemic tumor involving the periacetabular pelvis (Group 2). All resections included excision of the acetabulum. Patients ranged in age from 24 to 76 years (average, 59.8 years). Local control was achieved in all patients. Wide margins were obtained in all patients with primary pelvic tumors. Functional outcomes were rated as follows excellent (10), good (2), fair (1), and poor (4). Three patients, all of whom had pulmonary metastasis before surgery, died within 8 months of surgery. Of the remaining 14 patients, 5 patients died between 6 and 28 months after the index procedure. At the end of the followup period, 9 patients were still alive (6 in Group 1 and 3 in Group 2), with a followup period ranging from 15 to 62 months (average, 33.4 months). The overall results for surviving patients were 7 excellent and 2 good results, with no fair or poor results.
120 cells were recorded from area 17 of cats and their length and width summation properties were investigated by drifting sinusoidal grating patches. The study shows that (1) for most of the cells, the RF was roughly equal in length and width, while most of the integration fields (IFs) were of elongated shape either in length or in width; (2) the size of the IFs was mostly 2-7 times (mean 3.7 times) the size of the related RFs, no significant difference was seen between the simple and the complex cells; (3) the size of the IFs tends to increase with increase of retinal eccentricity of the RFs; (4) for neurones whose RF located near the vertical meridian (VM), the IF extended bilaterally into both the contra- and the ipsilateral sides to about the same extent, but the strength of the modulatory effect of the ipsilateral field is weaker than that of the contralateral field. The above results indicate that neurones of the primary visual cortex integrate visual information from an extensive visual field, and the integration effect may cross the VM to the ipsilateral side.
Thirty-six patients with achalasia were examined by gastroesophageal scintiscan after esophagomyotomy (Heller's myotomy) in order to survey esophageal emptying ability and gastroesophageal reflux. Sixteen of the 36 patients had additional antireflux procedures. After oral intake of orange juice containing 5mCi99mTc-DTPA, the patients were examined for esophageal emptying ability by ECT. Gastroesophageal reflux was observed under variant intraabdominal pressure. In sole Heller's myotomy group, esophageal emptying rates at 1 and 2 minutes were better than those of Heller plus antireflux group (P < 0.05). However, there was no significant difference in occurrence of gastroesophageal reflux between the two groups (P > 0.05). In this series, Heller's myotomy plus antireflux procedures obstructed esophageal emptying rather than hindered gastroesophageal reflux, so that any antireflux procedure should not be undertaken after Heller's myotomy.
A new anti-reflux procedure, cardiac oblique invagination, was designed. Having succeeded in animal experiment, we performed this procedure clinically. Sixteen patients with sliding hiatus hernia and one with paraesophageal hernia were operated on. Reflux symptoms disappeared postoperatively. Esophageal manometric study showed that the pressure of HPZ elevated and no abnormal reflux was found by 24-hour esophageal pH monitoring. The effectiveness of this method was assumed that the abdominal segment of the esophagus, His angle, and cardiac rosette were well established and, also, this procedure fitted in with LaPlace's law. The method was simple, transabdominal, easy to teach, and it provided excellent short-term result.
We observed the urinary calcium in 103 patients in the third trimester of pregnancy and the relation between the 24 hour calcium excretion and the calcium/creatinine ratio of a single void urine sample. The study population included 75 normal pregnant women and 28 pregnant woman with pregnant hypertension syndrome. The 24 hour urinary calcium excretion in the patients with pregnant hypertension syndrome was significantly lower (0.70 +/- 0.36 mmol/L) than that in normal pregnant women (4.00 +/- 1.90 mml/L) P < 0.0005. The 24 hour calcium excretion correlated well with the calcium to creatinine ratio of a single void morning urine sample in the two groups. We conclude that the urinary calcium excretion can be used as an indicator for pregnant hypertension syndrome. The 24 hour urinary calcium excretion can be estimated from a single void urine sample. Pregnant hypertension syndrome is associated with hypocalciuria, probably due to increased tubular reabsorption of calcium.
One hundred and fifteen term pregnancies (62 normal pregnancies, 53 high risk pregnancies) were observed by umbilical artery Doppler velocimetry (UmA S/D ratio) and antenatal fetal heart rate monitoring (NST), and 37 of them were also observed by umbilical artery blood-gas analysis at birth. We compared the effects of these three methods to predict the neonatal outcome. The standards of the neonatal poor outcome were 5-min Apgar score < or = 7 and/or a birth weight < 2500g (SGA). The results were: (1) The neonatal poor outcome were more frequently observed in the abnormal UmA S/D ratio (> or = 3.0) group and in the UmA pH < or = 7.2 group (P < 0.005, P < 0.025, respectively), but there was no significant difference between the NST reactive or nonreactive groups (P > 0.05); (2) The neonatal acidosis at birth was also associated with the abnormal UmA S/D ratio (> or = 3.0); (3) The sensitivities of UmA S/D ratio, UmA pH, NST to predict the 5-min Apgar score < or = 7 were 60.0%, 60.0%, 20.0% respectively; the specificities 84.6%, 81.3%, 81.8% respectively. And their sensitivies to predict SGA were 100.0%, 100.0%, 40.0% respectively; the specificities 86.4%, 80.0%, 82.7% respectively. Our data show that UmA S/D ratio and UmA pH are better than NST in the prediction of neonatal outcome, and the abnormal UmA S/D ratio is closely associated with neonatal acidosis at birth.
The causes and change of maternal death in this hospital from 1949 to 1990 was analyzed. The average maternal mortality of 42 years was 150.22/10(5) livebirths. The 42 years was divided into four periods which were 1949-1960, 1960-1970, 1971-1980 and 1981-1990. The results showed that the maternal mortality rate lowered from 365.31/10(5) livebirths in first period to 43.67/10(5) livebirths in the 4th period. The difference was markedly significant P < 0.01. The direct obstetric causes of maternal deaths in these periods were 30.00%, 23.81%, 25.00% and 55.56% respectively and increased in the 4th period. Obstetric hemorrhage (55.71%) pregnancy induced hypertension (31.43%) and preperal infection (11.43%) were the three main causes of maternal deaths in direct obstetric causes. Cardiac diseases (40.00%) was the leading cause in indirect causes.
The argon fluoride excimer laser is able to ablate the superficial cornea and to correct refractive problems. Photorefractive keratectomy (PRK) was performed on 103 myopic eyes ranging from -0.75D to -6.00D. We prospectively evaluated visual and refractive results that were followed for more than 6 months. Uncorrected visual acuity of 1.0 or better was achieved in 88.35%. The difference between attempted and achieved refractive correction was within +/- 1.00D in 94.17%. 10 eyes (9.71%) had trace to mild subepithelial hare and 19 eyes (18.45%) had loss of one line of best spectacle corrected visual acuity. The excimer laser PRK appears to be a predictable and effective method to correct myopia under -6.00D.
Sulfation of Achyranthes bidentata polysaccharide (Abps) with sulfuric acid or sulfur trioxide-pyridine or chlorosulfonic acid-pyridine was studied. A homogeneous sulfation method with good yield of 82.11% was obtained, using chlorosulfonic acid in an excess of pyridine. Sulfated Achyranthes bidentata polysaccharide was obtained as an amorphous sodium salt easily soluble in water. The UV and IR spectrum of Abps sulfate showed absorptions at 208, 268, 286 nm and 1232, 823.6 cm-1 respectively. The sulfur content of the products was found to be 20-22%. The degree of substitution varied from 2.8 to 3.2. It showed that the hydroxy group of Abps was almost completely esterified by chlorosulfonic acid. The Abps sulfate was shown to have high activity as anti-HBsAg and HBeAg. It is also effective on simple herpes virus type-I.
Xenografts of nude mice bearing human ovarian carcinoma cell line SKOV3 were transplanted using subrenal capsule assay (SRCA) in immunocompetent C57BL/6 mice. Multiple locations were chosen on both sides of the kidneys obtaining a total of 129 tumors. The volumes of the tumors were measured and histopathological examinations were conducted on the 4th, 6th, 8th, 10th, 12th and 14th days after transplantation surgery. The growth rates were noticed to be high on the 6-8th days. Lymphocytic infiltration reached a peak on the 8-12th day. On the 14th days the leukocytic infiltration and fibrosis almost surrounded the tumors. Tumor cells that could be found amounted to about 77.25%, 65.38%, and 52.17% respectively on the 4th, 6th and 8th days, but significantly decreased on 12-14th days. The above results suggested: (1) multiple SRCA on both sides proved to be practical and economical; (2) the xenografts of nude mice bearing hman ovarian carcinoma could be transplanted viably by SRCA for 8-10 days; (3) microscopic measurements of the transplanted tumor volume did not represent the real status of the tumor growth, and microscopic evaluation was necessary.
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