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21.
As an avian embryo grows within a eggshell, the whole egg is moved by embryonic activity and also by the embryonic heartbeat. A technical interest in detecting minute biological movements has prompted the development of techniques and systems to measure the cardiogenic ballistic movement of the egg or ballistocardiogram. (BCG). In this context, there is interest in using an electromagnetic induction coil (solenoid) as another simple sensor to measure the BCG and examining its possibility for BCG measurement. A small permanent magnet is attached tightly to the surface of an incubated egg, and then the egg with the magnet is placed in a solenoid. Preliminary model analysis is made to design a setup of the egg, magnet and solenoid coupling system. Then, simultaneous measurement with a laser displacement measuring system, developed previously, is made for chicken eggs, indicating that the solenoid detects the minute cardiogenic ballistic movements and that the BCG determined is a measure of the velocity of egg movements.  相似文献   
22.
R Tamura  T Ono  M Fukuda  H Nishijo 《Hippocampus》1992,2(3):287-306
The purpose of this study was to investigate, during the performance of an object discrimination task, responses of neurons in the monkey hippocampal formation to the sight of several objects that have biological meaning, and compare these responses with those of amygdalar neurons studied previously using the same task. Neuronal activity in the hippocampal formation of conscious monkeys was recorded during performance of a task that led to presentation of familiar rewarding, familiar aversive, or unfamiliar objects. Of 864 neurons recorded in the hippocampal formation and adjacent cortices, 160 (18.5%) responded to the sight of a certain object(s). Responses to the sight of different kinds of objects were analyzed in detail. Nondifferential neurons (n = 73) responded to different objects with no significant difference in response magnitudes, and differential neurons (n = 87) responded to different objects with different response magnitudes. Of the differential neurons, 23 responded more strongly to rewarding objects than to other objects (rewarding-object-dominant neurons), but the magnitude of responses to objects did not necessarily correlates with the order of preferences to the objects as determined from observation of animal behavior. Aversive-object-dominant neurons (n = 13) responded more to aversive objects than to other objects. Unfamiliar-object-dominant neurons (n = 7) responded more to unfamiliar objects than to familiar objects. Selective neurons (n = 10) responded selectively to only one object or one category of objects. Fourteen of the rewarding- or averse-object-dominant neurons were tested in extinction or reversal trials. In 12 of 14 neurons, responses to a rewarding or aversive object did not change, or slightly weakened, in extinction or reversal trials. The results suggest the following. (1) Responses of rewarding- or aversive-object-dominant neurons may be involved in object-reward or object-aversion association. However, responses of many of these neurons might reflect past inputs to reinforcement rather than extant emotional processing. (2) Responses of unfamiliar-object-dominant neurons may be involved in recognition of objects based on their familiar or unfamiliar aspects. These results are further discussed and compared with responsiveness of amygdalar neurons.  相似文献   
23.
In connection with gallstone (GS) formation after gastrectomy for cancer, we examined alteration of the composition of gallbladder bile after subtotal gastrectomy with truncal vagotomy. Of 11 mongrel dogs with cholecystostomy, 3 underwent B-I and 4 B-II gastrectomy. Four dogs without gastrectomy were served as controls. Bile was collected for 12 months. Bile acids were quantified by GLC. The bile was cultured for bacteriology. TBA did not significantly differ among the three groups of the dogs. In the two gastrectomized groups, CDA (a secondary bile acid) kept a higher level and CA (a primary bile acid) maintained a lower concentration compared with those in the controls. A remarkable increase of non-conjugated bile acids was recognized in both gastrectomized groups. Lithogenicity was low for all of the 3 groups. All but 1 control dog incurred bile infection that persisted long. Black pigment stones containing calcium bilirubinate developed in 1 of the 3 B-I and 2 of the 4 B-II dogs but none in the controls. The bile infection seemed to be involved in the development of GS. As the alteration of bile composition and GS occurred solely in the gastrectomized dogs, subtotal gastrectomy with truncal vagotomy might precipitate the GS formation.  相似文献   
24.
Laparoscopic surgery has been widely performed for removing the gallbladder and the pelvic lymph-nodes in recent years. We have applied laparoscopy technique to nephrectomy and here we describe our procedures and the clinical results. The patient is placed in the supine position under general anesthesia. After a 4 liter CO2 pneumoperitoneum is induced, five trocars are inserted into the abdominal cavity through the ipsilateral abdominal wall. The patient is then turned to the lateral position to displace the bowel medially. The ipsilateral colon is reflected medially after incision of the parietal peritoneum was made along the line of Todt to expose the retroperitoneum. The ureter was identified and dissected. It was secured with 4 clips (2 clips on the renal side and 2 on the distal side) and then cut with scissors. The renal vein and artery were then dissected and separately ligated with clips as described above. These vessels were also cut. The upper pole of the kidney was dissected out and the adrenal gland was left in place. The kidney thus became completely free within the abdomen. It was then grasped by the forceps through a 10 mm sheath positioned below the umbilicus. After incising the abdominal wall, the kidney was removed from the abdominal cavity with the grasping forceps and the sheath. By this procedure right nephrectomy was completely performed in a 56-year-old female patient and left nephrectomy in a 56-year-old male patient. The underlying disease was recurrent pyelonephritis secondary to renal calculi in both cases. The operative times were 221 min and 346 min, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
25.
Objective: To induce adipocyte differentiation in vitro by adipose-derived stromal cells (ASCs) harvested from transgenic mice with green fluorescent protein (GFP) and assess the possibility of constructing adipose tissues via attachment of ASCs to typeⅡcollagen scaffolds. Methods: Inguinal fat pads from GFP transgenic mice were digested by enzymes for isolation of ASCs (primary culture). After expansion to three passages of ASCs, the cells were incubated in an adipogenic medium for two weeks, and the adipocyte differentiation by ASCs in vitro was assessed by morphological observation and Oil Red O staining. Then they were attached to collagen scaffolds and co-cultured for 12 hours, followed by hypodermic implantation to the dorsal skin of nude mice for 2 months. The newly-formed tissues were detected by HE staining. Results: The cultured primary stem cells were fibroblast-like and showed active proliferation. After being incubated in an adipocyte differentiation medium, the lipid droplets in the cytoplasm accumulated gradually and finally developed into mature adipocytes, which showed positive in Oil Red O staining. A 0. 5-cm3 new tissue clot was found under the dorsal skin of the nude mice and it was confirmed as mature adipose tissues by fluorescent observation and HE staining. Conclusions: ASCs can successfully differentiate adipose tissues into mature adipocytes, which exhibit an adipocyte-like morphology and express as intracytoplasmic lipid droplets. It is an efficient model of adipose tissues engineered with ASCs and type I collagen scaffolds.  相似文献   
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28.
AIM: We administered the herbal medicine Dai-Kenchu-To (DKT) to children with severe chronic constipation or with severe constipation after surgery for anorectal malformations. We then objectively assessed the effect of DKT on anorectal function by manometric study in addition to using a clinical scoring system. PATIENTS AND METHODS: Ten children with severe chronic constipation and 5 children with severe constipation after surgery for anorectal malformations were assessed. These 15 children received 0.3 g/kg/day of DKT for periods ranging from 3 months to 1 year. We objectively assessed their bowel function, sphincter function and rectal reservoir function by anorectal manometry and clinical scoring. RESULTS: In 10 children with severe chronic constipation, the clinical score after administration of DKT (7.2 +/- 0.8) improved significantly compared with that before administration of DKT (4.6 +/- 2.9) (p < 0.02). The threshold sensation volume and the maximum tolerable volume after administration of DKT significantly (p < 0.05; p < 0.01) decreased (128 +/- 63 ml vs. 69 +/- 18 ml; 229 +/- 99 ml vs. 144 +/- 47 ml), and rectal compliance after administration of DKT also significantly (p < 0.05) decreased (12.4 +/- 10.9 ml/cmH(2)O vs. 4.7 +/- 3.9 ml/cmH(2)O). CONCLUSION: The present study demonstrated that DKT had a favorable clinical effect on severe constipation in children, and anorectal manometry showed an improvement in their rectal reservoir functions. It appears that the results were secondary to DKT-stimulated peristalsis of the intestine, which promoted regular bowel habits.  相似文献   
29.
AIM OF THE STUDY: Although a bleeding tendency as a first symptom is a critical condition in congenital biliary dilatation (CBD), the clinical details of this symptom remain unclear. We assessed this condition in children with CBD in this paper. MATERIALS AND METHODS: Sixty-five children with CBD were treated at our institute between 1983 and 2004. The children, initially presenting with bleeding manifestations such as intracranial hemorrhage and bloody stools, were defined as the bleeding group, and the remaining children with digestive symptoms such as abdominal pain and vomiting were defined as the digestive group. The clinical features were compared between these two groups. RESULTS: In 6 of the 65 cases, bleeding manifestations were noted (9.2 %). All six had cystic-type choledochal dilatation. The mean age of the bleeding group was significantly younger than that of the digestive group, and bleeding was more frequent, especially in infants less than 12 months of age. In a laboratory study, the bleeding group showed a more prolonged blood coagulation time than the digestive group did. Serum amylase and lipase levels in the bleeding group were almost normal, while those in the digestive group were significantly higher. The direct bilirubin level in the bleeding group was significantly higher than that in the digestive group. CONCLUSIONS: Disturbed blood coagulation due to vitamin K deficiency related to cholestasis results in a bleeding tendency in children with CBD. Therefore, pediatric surgeons should be aware of this rare but critical condition which can be prevented by rapid and precise treatment with vitamin K supplementation.  相似文献   
30.
抑郁症焦虑症状和焦虑症的抑郁症状   总被引:3,自引:1,他引:2  
目的 探讨抑郁症和焦虑症的抑郁和焦虑症状的差异 ,为鉴别诊断提供依据。方法 使用HAMD和HAMA对5 5例抑郁症患者和 2 0例焦虑症患者进行评定。结果  (1)抑郁症组绝大部分为中、重度抑郁 (92 .7% ) ,焦虑症组无一例为重度抑郁 ;(2 )抑郁症组的HAMD总分和除焦虑 /躯体化以外的因子分均显著高于焦虑症组 (P <0 .0 5或P <0 .0 1) ,(3)抑郁症患者和焦虑症患者的HAMD和HAMA评分均呈显著性正相关 (P <0 .0 0 1)。结论 HAMD总分有助于鉴别抑郁症和焦虑症。  相似文献   
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