1989年 · 第102卷第01期

Organic acids in unstimulated saliva and extracellular fluids of dental plaques from 12 middle school students were measured by ion-chromatography. The acids in the plaques were analyzed before and 5-10, 30-35, 60-65 minutes after rinsing with 10% sucrose solution. The differences of the acids between the extracellular fluids of resting plaques and unstimulated saliva were significant. In the extracellular fluids of plaques, the concentration of high pK acids, i.e. acetic and propionic acids was higher than that of low pK acids i.e., lactic and formic acids before and after sucrose rinse. The relations of time-dependent changes between the ratio of low pK to high pK acids and pH were observed in the extracellular fluids of plaques after sucrose rinse. No significant difference of lactic acid concentrations was found between the caries-active and caries-free subjects 30-35 minutes after sugar rinse. The concentration of acetic acid was much higher in the extracellular fluids of dental plaque at any time. It is suggested that there may be some relationship between acetic acid and caries process.

Thirteen hypercoagulation parameters related to coagulation, anticoagulation, platelet functions, dynamics of clot formation and hemorrheology were determined in 15-109 patients with thromboangiitis obliterans (TAO). The results showed that VIIIR= Ag, PAdT, PagT, HPF, and whole blood and plasma viscosity were elevated, fibrinogen elevated in the active stage, AT-III declined, RBC electrophoresis time prolonged, and changes suggesting hypercoagulation in thromboelastogram. All these indicated the existence of a hypercoagulation state in TAO patients, which could contribute to the process of thrombosis. The relationship between immune reactions and blood hypercoagulability could be crucial in the pathogenesis of TAO. Immune reacOons causing injury of vascular endothelium play a primary and fundamental role, and blood hypercoagulability could play a secondary but important role in the course of the disease.

The serum lipid levels (mean±SD) of 3312 healthy urban and rural inhabitants over 40 years of age in Shanghai were studied. The results were: cholesterol 166.7±30.9 mg/ml, triglyceride 81.1±42.3 mg/dl, HDL-cholesterol (HDLc) 57.4±11.6 mg/dl, HDL2c 20.6±9.8 mg/dl and HDL3c 37.1±7.8 mg/dl. Dietary surveys were carried out in 512 of these subjects and their average daily nutrient intake was estimated to be: total calories 2 577 Kcal, proteins 656 g (50.7 g of vegetable proteins), fat 69.1 g (P/S ratio 0.70), carbohydrates 423 g, cholesterol 282 mg, dietary fibres 23.5 g, sodium 4993 mg, potassium 2 618 mg and magnesium 575 mg. The serum lipid levels of urban and rural inhabitants were compared. Total cholesterol levels were significantly higher in urban inhabitants of all age groups and of both sexes, while triglyceride levels were significantly higher in urban inhabitants of certain age groups. However, HDLc levels, particularly HDL2c levels were significantly higher in rural inhabitants of most age groups and of both sexes. The above differences were probably the result of differences in dietary patterns and nutrient intake between urban and rural inhabitants.

The cytoplasm of human bile ductule epithelia was found to be Type V collagen positive, demonstrating that the epithelia were able to generate this type of collagen. The ductules proliferated greatly with Type V collagen positive cytoplasm in piece-meal necrosis of chronic active hepatitis (CAH). The capillary-like bile ductules inside human hepatic lobules were identified. Our findings might explain the mechanism of fibroplasia in CAH.

NBT-PABA test was performed in 72 subjects with simultaneous determination of the plasma PABA time-concentration curve. The curve in 25 controls after oral administration of N-benzoyl-L-tyrosyl-P-aminobenzoic acid (NBT-PABA) peaked (3.88±0.78µg/ml, M±SD) at the third hour. In patients with chronic pancreatitis (24) and pancreatic carcinoma (6), the curves were flattened, and peaked at the fifth hour (2.7±1.4pg/ml, M±SD), and fourth hour (3.14±2.26pg/ml, M±SD), respectively. The discrimination between the controls and patients with chronic pancreatitis was most significant in the third-hour plasma PABA concentration (P<0.0001). This study shows that determination of the third-hour plasma PABA concentration is better in sensitivity and specificity than the 6-hour urinary excretion of PABA, suggesting that the third-hour plasma PABA concentration after oral administration of NBT-PABA might be a sensitive index of exocrine pancreatic function test.

Growth hormone (GH) secretion is mediated by hypothalamic factors, mainly growth hormone releasing factor (GRF) and somatostatin (SS). The hypothalamic hormones, under direct neurotransmitter control, stimulate GH secretion through different central mechanisms. Atropine, an anticholinergic agent, can cross the blood-brain barrier and inhibit GH secretion stimulated by exercise and sleep in normal persons. In order to study the inhibiting effect of atropine on GH release and whether glucose can be replaced by stropine, normal persons and acromegaly patients were observed during exercise, after stropine, and 100 g glucose loading. The results confirmed that GH secretion increases after exercise and that this GH elevation can be inhibited by stropine in normal subjects. But in acromegaly patients high basal GH levels can not be inhibited by 100 g glucose loading or 0.6 mg atropine during the active phase of the disease. Blood sugar levels remained unchanged during the atropine test. It is suggested that the atropine test can be used as a GH inhibitory test in acromegaly patients with overt diabetes.

It is well known that growth hormone (GE) secretion and regulation in diabetics are abnormal. In order to evaluate the response of GH to nonphysiological stimuli in diabetics, a thyrotropin-releasing hormone (TRH) test (500 μg by IV bolus injection) was carried out in 12 patients with insulin-dependent diabetes (IDD, 6 males and 6 females). 11 noninsulin-dependent diabetes (NIDD, 5 males and 6 females), and 10 normal controls (6 males and 4 females). The results showed that the basal serum GH levels in diabetics were higher than that in normal controls and it was even higher in IDD than in NIDD. Following the TRH stimulus, the mean peak level of GH in IDD was the highest among the three groups, the differences being statistically significant (F=9.323, P<0.01). It was concluded that a nonspecific response to TRH of GH did occur in IDD, and the peak values were even higher in female than in male subjects. A negative correlation existed between the GH peak values and the age of the patients as well as in the controls. This supported the view that GH responsiveness to TRH has a tendency of progressive decline with age. However, no significant correlation was found between the peak value of GH and the blood glucose level or the microangiopathic complications. The mechanism of TRH stimutation on GH release in diabetics is discussed.

The vascular pedicled periosteum was used in II cases in our hospital for the treatment of femoral neck fracture with good result. The follow-up period ranged from 2 to 6 years, with an average of 4 years. Animal experiment was made to elucidate the repairing process. It demonstrated that the pedicled periosteum played double roles, namely, blood supply and osteogenesis. The clinical and experimental results are presented.

Local spinal cord ischemia model was established in 11 adult dogs. The anterior spinal artery, posterior spinal artery and radicular artery were cauterized with bipolar cautery. Ischemia of this segment of spinal cord was thus produced followed by paraplegia. The pathological findings of this spinal cord segment were softening and necrosis. The establishment of this animal model of segmental spinal cord ischemia is beneficial to scientific research in basic medicine and clinical practice.