[Preliminary study on soilless cultivation techniques of Panax quinquefolium L]

Our experiment has shown 1. Vermiculite with sand (volume 1:1) is a good substrate of soil for American Ginseng. The yield and contents of ginsenoside of American ginseng in this soilless substrate are a little higher than those in ordinary soil. 2. This kind of substrate can be used continuously with fewer occurrences of insect pest and plant diseases and contributes significantly to the reduction of production cost.

Pylorus and antroseromuscular flap-preserving gastrectomy--a new type of reconstruction after subtotal gastrectomy for treatment of gastroduodenal ulcer: clinical and experimental study

To avoid motility disturbances after Billroth gastrectomy, the authors designed pylorus and antroseromuscular flap-preserving subtotal gastrectomy (PAFPG). Results showed that gastric motility and emptying time of dogs after PAFPG were close to normal. PAFPG was applied to 125 consecutive patients with gastroduodenal ulcers (gastric ulcer, 15 patients; duodenal ulcer, 94 patients; and combined ulcers, 16 patients) confirmed by barium examination and fibro-gastroendoscopy. All patients recovered smoothly, none of them had postoperative complication. Gastric acid output reduction rates were as follows: basal acid output, 85.05% +/- 8.13%; maximal acid output, 81.76% +/- 10.85%; peak acid output, 81.42% +/- 10.15%. The incidence of postoperative enterogastric reflux (endoscopically) and the concentration of cholic acids in gastric juice were significantly lower in patients after PAFPG than after Billroth I or II gastrectomy. Results suggest that PAFPG reduced gastric acid outputs definitely and overcame adverse motility consequences after Billroth I or II gastrectomy desirably.

[The preservation capacity of water and fertility of soilless cultivation substrate for Panax quinquefolium L.)]

The preservation capacity of water and fertility of several soilless cultivation substrates for Panax quinquefolium was compared in a large area. The data indicate that vermiculite mixed with sand (volume 1:1) is the most suitable soilless substrate for P. quinquefolium, for it is loose and features good preservation of fertility, water retaining, drainage, and air permeability. Timely analysis of nutrient contents in the substrates during cultivating period may serve as a guideline for correct application of fertilizer.

An MRI perfusion model incorporating nonequilibrium exchange between vascular and extravascular compartments

A model of MRI signal intensity which is a function of perfusion is developed based upon the assumption that biological tissue can be represented by a blood and tissue compartment. The longitudinal magnetization is derived from the Bloch equations which are modified to model the magnetization in both the blood and tissue as a function of the following physiological parameters: blood flow velocity; perfusion fraction, which in the model is parameterized in terms of the ratio of the cross-sectional areas of the tissue and blood compartments; diffusion; rate of exchange between the blood and extravascular tissue compartments. Simulations of slice profiles excited by a repetitive sequence of 90 degrees slice-selective pulses show that the signal intensity in the blood and tissue compartments are modulated by the physiological parameters. A key factor in the modulation of the MRI signal is a time-of-flight effect whereby unexcited spins perfuse the excited region and exchange with blood and tissue compartments, thus immediately increasing the slice signal intensity but also delaying the spin exits from the slice, thereby decreasing their contribution to slice signal intensity in future repetitive pulse measurements.

[Clinical uses of digital subtraction arthrography of the temporomandibular joint]

In the present study, digital subtraction arthrography of TMJ upper cavity was performed in 20 cases with TMJ dysfunction syndrome. It was found that digital subtraction arthrography of TMJ can eliminate various overlapping imaging interference of skull components and has great diagnostic value for TMJ dysfunction syndrome, especially for the diagnosis of small meniscus perforation and the location of meniscus perforation. If this technique can be combined with dynamic observation of TMJ arthrography, the diagnoses for various displacement of meniscus can be made more exactly. However, it is impossible to carry out dynamic observation for TMJ when we use this technique only. This is its disadvantage. Therefore, the best way is to combine arthrographic dynamic observation or arthrographic fluoroscopic observation with digital subtraction arthrography.

[Effects of sodium molybdate on guinea pig atria contractility]

Sodium molybdate (Mo) 10-1000 mumol/L markedly reduced the contratile force of left atria isolated from guinea pig. Mo 100 mumol/L obviously reduced the heart rates in right atria, markedly prolonged the functional refractory period from 185 +/- 12 to 245 +/- 4 ms and inhibited the resting potentiation. Mo 100 and 300 mumol/L reduced the frequency-dependent positive staircase phenomenon. However, verapamil 25 mumol/L reversed the frequency-dependent positive staircase phenomenon to negative one. The mechanism can be explained by the effect on Ca2+ movement in the heart atrium.

[Effects of concentration and ratio of N, P and K on seedlings of Panax quinquefolium L]

Results of the orthogonal experiment of N, P and K are as follows: (1) The highest growth rate occurs in treatment 4 (N100ppm, P25ppm, K250ppm) and other features are also good. So this treatment can be used in hydroponics of seedling of P. quinquefolium. (2) The influences of N, P and K concentration on the contents of ginsenosides in different parts of seedling are different. The content of ginsenosides in aerial part is 14.72-16.72%, higher than 3.24-4.00% in root.

Reflectance diagram-aided technique for optical coating design and monitoring

An amplitude reflectance diagram is a useful tool for visualizing the relationships between the performance of an optical coating and the optical parameters. This paper gives a brief description of the construction and characterization of the reflectance diagrams for different indices. Then, applications of reflectance diagramaided techniques to the design of both phase dispersion-induced narrow reflection and transmission filters, as well as to the optical monitoring of the symmetric multilayers of types (A2BA) and (AB2CBA), are illustrated. Some experimental results of phase dispersion-induced narrowband filters are reported.

Apolipoprotein A-I and A-II levels in an Australian population

Values for apolipoproteins A-I and A-II (apo A-I and apo A-II) are reported for 389 women and 390 men in the town of Busselton, Western Australia. Apo A-I levels were found to be relatively constant with age in men but to rise with age in women. Apo A-II levels remained constant with age in men until older age, when they declined, but rose with age in women, showing a fall in the oldest age group. Apo A-I levels were greater in women than in men, but apo A-II levels were lower in younger women than in younger men, and higher in older women than in older men. On stepwise multiple regression analysis, neither apo A-I nor apo A-II levels showed an independent relationship with age in women; the same was true for apo A-I in men. Alcohol consumption was directly associated with apo A-I and A-II levels in both sexes; adiposity was inversely associated with apo A-I levels in both sexes but with apo A-II only in women. Triglyceride levels showed an inverse association with apo A-II in women. Frequency of exercise was independently and directly associated with apo A-I and A-II levels in women only.

Contemporary rural-urban migration of the Chinese population

The author examines rural-urban migration in China. "The present article provides an estimate of the volume of this population flow since 1949, based on a survey of population flow statistics from 74 cities, and discusses the theories and policies on migration."

Study of different phases in growth cycle of human bone marrow cells and their growth speed, using rat-human cell hybridization, premature chromosome condensation, and sister chromatid differentiation techniques

The cytokinetic activity of bone marrow cells is an indication of hemopoietic status. In the routine examination of bone marrow smears, only M phase can be identified, whereas the different phases of the remainder of the cell cycle are not possible to determine. However, by using premature chromosome condensation and bromodeoxyuridine differential staining techniques, cell stage and cell kinetics can be easily determined. Ninety-eight samples of human bone marrow were collected, cells were hybridized with mitotic M3 cells, and 5016 randomly selected hybrid cells were analyzed for cell stage. Our data demonstrated that 80.37% of the cells were in G1 phase, 12.66% were in S phase, 5.29% were in G2 phase, and 1.68% were in M phase. In specimens that had been cultured for 48 h in the presence of bromodeoxyuridine, 57.46% had completed at least two rounds of DNA replication. In 72-h specimens, 69.27% of the cells had completed at least two S phases. In 96-h specimens, 2S and 2S+ cells occupied 74% of the cell population. The use of cell hybridization techniques, premature chromosome condensation, and bromodeoxyuridine-dependent differential staining revealed the phases of the cell cycle distinctly, as well as the kinetics of cell growth.