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1.
1. [U-(14)C]Glucose was infused into one or both testicular arteries of ten conscious rams and the specific activity of the glucose taken up by the testis was compared with the specific activity of the carbon dioxide produced by the testis. 2. Equilibration had occurred after infusion for 3hr. when a mean of 68% of the carbon dioxide was being derived by the testis from blood glucose and 86% of the glucose taken up by the testis was being oxidized to carbon dioxide. After 5hr. infusion, these values were 71% and 83% respectively. 3. In four other conscious rams, [1-(14)C]glucose was infused into one testicular artery and [6-(14)C] glucose into the other and the ;specific yields' of carbon dioxide calculated for the two forms of glucose. 4. From these values, it was calculated that a mean of 9.3% of the glucose taken up by the testis was metabolized via the pentose cycle.  相似文献   

2.
This study was designed to investigate the respective damping properties of the annulus fibrosus and nucleus pulposus of the intervertebral disc during propagation of vibration waves through the osteoligamento-muscular axis of the spine. The study was conducted on a 8-10 kg deeply anesthetized baboon. In the first surgical phase five accelerometers were implanted in the first sacral vertebra and on the anterior side of the four lower lumbar vertebrae. The bioinstrumented animal was placed in a restraining chair and exposed to narrow-bandwidth (0-100 Hz) 0.16 G RMS random vibration. Once data was recorded, the nuclei pulposi of the studied discs were removed by suction, the surrounding annuli remaining intact. The still deeply anesthetized animal was again exposed to the same 0-100 Hz, 0.16 G RMS vibration. Results were analyzed and their reproducibility was tested on three animals.  相似文献   

3.
目的:探讨腹部X 线与CT 扫描鉴别急性肠梗阻的准确性,为临床诊断提供参考。方法:选取2011年8 月-2013 年8 月我院 收治的66 例急性肠梗阻患者的临床资料进行回顾分析。所有患者均经手术活检或病理诊断证实为急性肠梗阻。术后患者均行腹 部X 线及CT扫描检查,对两种方法判断肠梗阻的发生、梗阻部位、类型及病因与手术病理结果进行比较,评价并分析两种检查 方法的准确率。结果:66 例肠梗阻患者中,X线检出率为89.39%,CT 检出率为95.45%。X 线诊断小肠梗阻准确率为72.10%,CT 为86.05%;X线诊断结肠梗阻准确率为69.57%,CT 为86.96%。X线诊断肿瘤准确率为69.57%,CT 为86.96%;X线诊断肠粘连 准确率为67.86%,CT 为82.14%;X 线诊断肠套叠准确率为60.00%,CT 为80.00%;X线诊断单纯性机械性肠梗阻准确率为78.72%,CT为82.98%;X线诊断绞窄性肠梗准确率为73.68%,CT 为78.95 %。CT 对肠梗阻部位、病因及类型的诊断准确率高于腹部X 线片,差异具有统计学意义(P<0.05)。结论:腹部X 线与CT 用于诊断急性肠梗阻具有较高的准确率,但CT 对于肠梗阻部位、梗阻类型及梗阻病因的诊断优于X线片。  相似文献   

4.
目的:探讨腹部X线与CT扫描鉴别急性肠梗阻的准确性,为临床诊断提供参考。方法:选取2011年8月-2013年8月我院收治的66例急性肠梗阻患者的临床资料进行回顾分析。所有患者均经手术活检或病理诊断证实为急性肠梗阻。术后患者均行腹部X线及CT扫描检查,对两种方法判断肠梗阻的发生、梗阻部位、类型及病因与手术病理结果进行比较,评价并分析两种检查方法的准确率。结果:66例肠梗阻患者中,X线检出率为89.39%,CT检出率为95.45%。X线诊断小肠梗阻准确率为72.10%,CT为86.05%;X线诊断结肠梗阻准确率为69.57%,CT为86.96%。X线诊断肿瘤准确率为69.57%,CT为86.96%;X线诊断肠粘连准确率为67.86%,CT为82.14%;X线诊断肠套叠准确率为60.00%,CT为80.00%;X线诊断单纯性机械性肠梗阻准确率为78.72%,CT为82.98%;X线诊断绞窄性肠梗准确率为73.68%,CT为78.95%。CT对肠梗阻部位、病因及类型的诊断准确率高于腹部X线片,差异具有统计学意义(P〈0.05)。结论:腹部X线与CT用于诊断急性肠梗阻具有较高的准确率,但CT对于肠梗阻部位、梗阻类型及梗阻病因的诊断优于X线片。  相似文献   

5.
Oligonucleotide-directed site-specific mutagenesis was used to study the structure-function relationship of the positively charged amino terminus of the Escherichia coli outer membrane protein OmpA signal peptide. Mutations were isolated which reduced the overall charge of the amino-terminal region from +2 (wild type) to +1, 0, and -1, as well as one mutation from Thr to Ser at position 4. DNA encoding the wild type and mutant OmpA signal peptides was then fused in-frame to DNA encoding the mature regions of Staphylococcus aureus nuclease A and TEM beta-lactamase. In the case of both the beta-lactamase and nuclease fusions, normal processing was no longer observed when the charge at the amino terminus was reduced to zero or made negative. Differences between the two hybrid proteins were observed in the case of the Thr to Ser mutation. As expected, this mutation had no effect on the beta-lactamase hybrid; however, the processing rate of the nuclease hybrid protein was reduced to nearly one-half. Furthermore, this effect was essentially reversed when a Lys residue at position 3 was deleted. A model is presented which explains the differing effects of a signal peptide mutation on the secretion of different hybrid proteins based on kinetic differences in the translocation of the nuclease and beta-lactamase proteins.  相似文献   

6.
Twelve samples of milk of the platypus, Ornithorhynchus anatinus, had a mean content of 3 X 3% hexose. Of this, almost half was L-fucose. Of the total monosaccharides present in acid hydrolysates of the water-soluble carbohydrates, L-fucose constituted 33%, D-galactose 29%, glucosamine 20%, D-glucose 11% and sialic acid 7%. Free lactose was found in only trace amounts. In all samples, the major oligosaccharide was difucosyllactose, which represented 39-52% of the total hexose. Five higher neutral oligosaccharides (from penta- to nonasaccharides) were isolated and their monosaccharide compositions determined. Each contained one or more residues of fucose, glucosamine and galactose and one residue of glucose. The presence in the milk of 4-O-acetyl-N-acetylneuraminlactose was detected by thin-layer chromatography. All milk samples examined contained protein material (probably glycoprotein), which was not precipitated by chloroform-methanol extraction. No evidence was obtained for quantitative or qualitative changes in carbohydrates during the course of the lactation season except for a small decline in total hexose towards the end of the season.  相似文献   

7.
Experiments were conducted on awake rabbits to which trifluoperazine was given daily for 2 weeks in a dose of 1 mg/kg a day; a study was made of the reaction of the cortical neurones in response to the electrostimulation of its adjacent areas. In measuring the dispersions of the poststimular histograms it was found that under the effect of trifluoperazine there occurred a reduction of the value and the duration of the responses of the cortical neurons after the infliction of stimulation. The effect obtained after the administration of trifluoperazine was regarded from the point of view of aggravation of the signal conduction in the neuronal reticula.  相似文献   

8.
Serine dehydratase was induced in the kidneys of normal rats by the administration of either glucagon or dexamethasone. The increase in enzyme activity was associated with an increase in both enzyme protein and its mRNA, which were determined respectively by Western blot and RNA blot analysis. No apparent differences were observed between kidney and liver in the molecular weights of serine dehydratase proteins and the sizes of their mRNAs. Although kidney serine dehydratase was dramatically induced by either glucagon or dexamethasone, the liver enzyme was induced by glucagon but not by dexamethasone alone in the intact rat. On the other hand, liver serine dehydratase was induced in starvation, diabetes mellitus, and a high-protein diet. The kidney enzyme could not be induced under any of these conditions.  相似文献   

9.
The gene encoding cytotoxin (ctx) was cloned from Pseudomonas aeruginosa 158 and the nucleotide sequence was determined. The structural gene of ctx encodes the procytotoxin of 286 amino acid residues with a molecular mass of 31,681 Daltons. Procytotoxin was activated by removal of 20 amino acid residues from the C terminus with trypsin. The cloned ctx gene was not expressed in either an Escherichia coli strain or a cytotoxin non-producing strain of P. aeruginosa. An expression system for the ctx gene was constructed by placing the structural gene of ctx downstream of tac promoter on a broad host-range vector plasmid.  相似文献   

10.
1. The troponin complex from skeletal muscle contains approximately 1 mol of phosphate/80000g of complex, covalently bound to the troponin T component. 2. On prolonged incubation of the troponin complex or troponin T with phosphorylase kinase the phosphate content of troponin T was increased to approx. 3mol/mol. 3. On prolonged incubation of troponin I with phosphorylase kinase up to 1.6mol of phosphate/mol were incorporated. 4. Phosphorylation of troponin I was greatly inhibited by troponin C owing to the strong interaction between these proteins. Thus in the troponin complex troponin T was the main substrate for phosphorylase kinase. The phosphorylation of isolated troponin T was also inhibited by troponin C. 5. Troponin I was phosphorylated when the troponin complex was incubated with a bovine cardiac 3′:5′-cyclic AMP-dependent protein kinase. Troponin T either in its isolated form or in the troponin complex was not phosphorylated by bovine protein kinase to any significant extent under the conditions used. 6. If the troponin complex was dephosphorylated to 0.2mol/mol, or phosphorylated up to 2.5mol/mol there was no significant effect on the ability of normal concentrations to confer Ca2+ sensitivity on the adenosine triphosphatase of densensitized actomyosin.  相似文献   

11.
The degree of anterior curvature was measured on 30 cadaveric human femora, of unknown age and sex, by a spherometer. The mean anterior curvature radius was (1381.28 +/- 118.63) mm with a considerable interspecimen variation, the maximal value was 3262.66 mm and the minimal 695.54 mm.  相似文献   

12.
Some cytochemical observations were made on the secretion of the mucocytes in the surface epithelium of the different regions of the rabbit oviduct in anoestrous. It was concluded that the mucocytes of the oviduct contained mucin which was neutral or acid in nature. The three regions of the rabbit oviduct contained carboxylated acid mucopolysaccharide, but sialomucin was found in the infundibulum and sulphomucin was demonstrated in the isthmus and ampulla.  相似文献   

13.
Cytological and histochemical methods were used in order to establish that the intercalated cells of the ciliated epithelium of the rabbit's maxillary sinus mucosa performed gland function giving secretion formed in the shape of granules and represented by neutral mucopolysaccharides. Analysis of the morphology of intercalated cells, the amount of secretion in them, the shape and disposition of the Golgi apparatus and the nucleus allowed establishing 4 successive phases in their secretory cycle: the phase of synthesis, accumulation, aquosity and sectering. Under normal conditions of life the secretory activity of intercalated cells was asynchronous. In experiments with synchronization of the secretory activity by administration of pilocarpine it was established that the duration of the intercalated cells secretory cycle was 16-18 hours. Active participation of alkali phosphatase in the synthesis of secretion in the ciliated epithelium was noted.  相似文献   

14.
15.
L Andersen  N Keiding 《Acta anatomica》1990,138(4):348-351
The size of the fibrillar centres (FC) in nucleoli was investigated taking the Swiss cheese effect into account. Electron microscopy was performed on the neurons of the rat supraoptic nucleus after the secretion of vasopressin had been fully suppressed by water load, after the secretion had been stimulated by water deprival and in normal rats with water ad libitum. When the secretory activity was suppressed from a normal level to approximately no activity, the size of the individual FC was doubled. Moreover, with increasing secretory activity the number of FC per cell increased.  相似文献   

16.
《Theriogenology》1996,45(8):1457-1462
The aim of this study was to determine the influence of hand massage of mares' ovaries on breeding activity and hormonal changes in the winter anestrous period and during the luteal phase of the oestrus cycle. The experiment was conducted on 5 experimental and 5 control mares. In winter, (January) the experimental mares underwent 30-sec daily massage of both ovaries, for 30 d, and in summer (August) from the 6th day of the cycle to the occurrence of estrus. The sexual behavior of all mares was determined each day by individual teasing by a vigorous stallion, and the ovaries were checked by palpation per rectum and with an USG. Every second day blood samples were drawn from each mare to determine progesterone and estradiol in the plasma. Ovarian massage during deep winter anestrus had no significant effect on acceleration of the mares' active breeding season. Nevertheless, a higher concentration of estradiol was observed in the experimental group. These differences occurring on the 11th, 17th and 20th days were found to be significant (P ≤ 0.05). It was shown that during the summer period, in the luteal phase of the cycle, ovarian massage shortened the length of the estrous cycle, and ovulation was brought on somewhat earlier.  相似文献   

17.
Arterial distribution of the upper lip was investigated in this study. The location, course, length, and diameter of the superior labial artery and its alar and septal branches were determined on 14 preserved cadaver heads. Another cadaver head was used to show the arterial tree by the colored silicone injection technique. The superior labial artery was the main artery of the upper lip and always originated from the facial artery. The superior labial artery was 45.4 mm in length, with a range from 29 to 85 mm. The mean distance of the origin of the superior labial artery from the labial commissura was 12.1 mm. The superior labial artery was 1.3 mm in external diameter at its origin. The mean distance of origin of the superior labial artery from the lower border of the mandible was 46.4 mm. The alar division of the superior labial artery was mostly found as a single branch (82 percent). Its mean length was 14.8 mm and the mean diameter at the origin was 0.5 mm. The distance between the origins of the superior labial artery and the septal branch was 33.3 mm. The septal branch was single in most of the cases (90 percent). The mean length of the septal branch was 18.0 mm and the diameter at its origin was 0.9 mm. After all dissections, it was concluded that the arterial distribution of the upper lip was not constant. The superior labial artery can occur in different locations unilaterally and bilaterally, with the branches showing variability.  相似文献   

18.
1. The early demonstration of specific androgen binding sites in skeletal muscle suggested that androgen might be involved in the homeostasis of the tissue in adult mammals. 2. Following five weeks of androgen withdrawal, a noticeable increase in the plantaris (PLT) myosin heavy chain cleavage occurs. No other alteration of the contractile proteins pattern was detected. 3. No effect on the template activity of major mRNAs associated with the polysomal fraction was observed in GDX or GDX + TP group compared to control rats. 4. As opposed to the PLT muscle, the template activity of polyribosomes isolated from the androgen sensitive levator ani muscle displays a severe alteration following GDX. 5. Force-frequency analysis of PLT indicated however that the MHC modification was of no functional significance.  相似文献   

19.
The course of the revaccination reaction in mice immunized with different doses of sheep red blood cells was determined at different intervals after the primary stimulus. The maximum level of haemagglutinating antibodies in the secondary reaction was found after a high primary and secondary antigenic stimulus. On the contrary, if the level of haemolytic antibodies was determined, the higher was the primary antigenic stimulus, the lower was the secondary antibody response. Differences between haemagglutinins and haemolytic antibodies were also manifested in the earlier onset of the maximum haemolytic secondary reaction (five months after the first dose of antigen); the maximum haemagglutination response was not attained until eight months after the primary dose of antigen. The results comfirm that the basis of preparation for the secondary reaction is proliferation of immunologically activated Y cells; differences in the haemolytic and haemagglutination response are related to differences in the character of the antigenic determinants of sheep red cells.  相似文献   

20.
Summary

Two antidiuretic hormones are present in the corpora cardiaca of the locust, Locusta migratoria. They are located in the nervous and the glandular parts (NCC and GCC) respectively. A procedure was developed to avoid contamination of GCC by NCC. The peptide nature of the GCC hormone was established and its structural stability was studied.

Additional evidence regarding the role of cyclic AMP as second messenger of the GCC antidiuretic factor was presented.  相似文献   

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