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531.
Lungs of two chimpanzees (Pan troglodytes) were examined. The right pulmonary artery runs across the ventral side of the right upper lobe bronchiole and, then across the dorsal side of the right middle lobe bronchiole. Thereafter, it runs between the dorsal bronchiole system and the lateral bronchiole system, along the right bronchus. During its course, it gives off arterial branches which run along each bronchiole. The left pulmonary artery runs across the dorsal side of the left middle lobe bronchiole and then between the dorsal bronchiole system and the lateral bronchiole system. The branches of the pulmonary artery run mainly along the dorsal or lateral side of the bronchiole. The pulmonary veins run mainly along the ventral or medial side of the bronchioles, and between them. Finally, they enter the left atrium with four large veins, i.e. the common trunk of the right upper lobe vein and the right middle lobe vein, right lower lobe pulmonary venous trunk, left middle lobe vein, and left lower lobe pulmonary venous trunk.  相似文献   
532.
533.
Basic fibroblast growth factor in rat salivary glands   总被引:5,自引:0,他引:5  
We studied the occurrence and localization of basic fibroblast growth factor (bFGF) in rat salivary glands using a specific monoclonal antibody. It was shown that the extract of rat salivary glands has a pronounced stimulatory activity on the growth of bovine capillary endothelial cells, which is blocked by the addition of an antibody against bFGF. The concentration of bFGF in the submandibular/sublingual gland, as determined by radioimmunoassay, was 80% that in the brain. Immunocytochemistry revealed bFGF-immunoreactivity localized primarily in the epithelial cells lining the striated ducts and excretory ducts of the parotid, sublingual and submandibular glands. In addition, intense bFGF-immunoreactivity was observed in the granular convoluted tubule of the submandibular gland, localized predominantly in the agranular pillar cells, which lay in small numbers among the majority of weakly immunostained cells containing many apical secretory granules. At the electron-microscopic level, the immunoreactive material was distributed diffusely in the cytoplasmic matrix and nuclei of all immunoreactive cells, whereas it was absent from all cytoplasmic organelles including the secretory granules. These results indicate that bFGF is localized in different cellular and subcellular compartments from those of other growth factors in the duct system of rat salivary glands.  相似文献   
534.
The quantitative analysis of haemoglobin oxygenation of contracting human muscle during weight-lifting exercise was studied noninvasively and directly using near-infrared spectroscopy. This method was developed as a three-wavelength method which confirmed the volume changes in oxygenated haemoglobin (oxy-Hb), deoxygenated haemoglobin (deoxy-Hb) and blood volume (total-Hb; Oxy-Hb + deoxy-Hb). Nine healthy adult men with various levels of training experience took part in the study. Ten repetition maximum (10 RM) one-arm curl exercise was performed by all the subjects. Results showed that at the beginning of the 10-RM exercise, rapid increases of deoxy-Hb and decreases of oxy-Hb were observed. In addition, total-Hb gradually increased during exercise. These results corresponded to the condition of arm blood flow experimentally restricted using a tourniquet in contact with the shoulder joint, and they showed the restriction of venous blood flow and an anoxic state occurring in the dynamically contracted muscle. In three sets of lifting exercise with short rest periods, these tendencies were accelerated in each set, while total-Hb volume did not return to the resting state after the third set for more than 90 s. These results would suggest that a training regimen emphasizing a moderately high load and a high number of repetitions, and a serial set with short rest periods such as usually performed by bodybuilders, caused a relatively long-term anoxic state in the muscle.  相似文献   
535.
An important objective for patients with unresectable hepatocellular carcinoma (HCC) is the development of effective chemotherapy. We administered a combination of biological response modifiers and anticancer agents to 24 patients with unresectable HCC. Each case had an implanted infuser port which was connected to a catheter placed in the hepatic artery for the intraarterial (i.a.) administration of chemotherapy. The following agents were administered to each patient: recombinant interleukin-2 (800 000 JRU/day infused i. a. continuously for 6 days/week); OK-432 (5 KE injected i. a. twice in 4 weeks and i. m. three times per week); Adriamycin (10 mg injected i.a. twice in 4 weeks); cyclophosphamide (300 mg injected i. a. twice in 4 weeks), and famotidine (40 mg/day administered orally). Objective response was assessed according to tumor size measured by computed tomography and angiography before and after treatment. We observed a complete response (CR) in 4, partial response (PR) in 3, minor response (MR) in 7, no change (NC) in 7, and progressive disease (PD) in 3. The response rate (CR+PR+MR) was 58.3%. The overall 2-year survival rate was 52%. The 2-year survival rate of the responders (CR+PR+MR) was 80%, while that of the non-responders (NC+PD) was 0%. There was a significant difference between the responders and non-responders in respect to survival rate (P<0.05). The percentages of CD25+ cells, CD56+ cells, and Leu7-CD16+ cells and NK activity in the peripheral blood showed a significant increase following the regimen. Serum levels of tumor necrosis factor TNF rose after the initiation of OK-432. TNF levels were higher in the responders than in the non-responders. Adverse effects included high fever (all patients) and severe transient hypotension (15 patient) that was controlled by convervative therapy. Combined immunochemotherapy administered intraarterially may be a new strategy for treating unresectable HCC.  相似文献   
536.
Seasonal changes in several forms of nitrogen were investigated in the evergreen chamaephyte Pachysandra terminalis Sieb. et Zucc. growing in temperate evergreen coniferous forest. After plants sprouted new shoots, nitrogen accumulated largely as proteins in the leaves from summer to late autumn and, additionally, during a short spring period in the following year. Proteins accumulated in the overwintered leaves decreased markedly in summer, indicating that they were used for new shoot growth. A similar change was found in Fraction 1 protein. This is consistent with the seasonal changes in photosynthetic capacity and carboxylation efficiency observed in previous studies. The allocation of nitrogen to Fraction 1 protein increased in the spring, presumably to utilize better the relatively high light intensity at the forest floor before leaf expansion of the understory deciduous plants. In contrast to protein nitrogen, soluble nitrogen was present largely in stems and rhizomes. Aspargine was the major component of the amino acid pool in all organs throughout the year, especially in stems in summer. Since asparagine has the highest N:C ratio (2N:4C), an amino acid pool dominated by asparagine is economic in the use of carbon and advantageous for the carbon-limited environment of the forest understory.  相似文献   
537.
A cytosolic form of LC3 is conjugated to phosphatidylethanolamine by Atg7, an E1-like enzyme, and Atg3, an E2-like enzyme, during autophagy. To monitor intracellular autophagosomes and autolysosomes, GFP-LC3 is a useful tool. However, GFP-LC3 can aggregate without being conjugated to phosphatidylethanolamine, especially when GFP-LC3 is transiently expressed (Kuma A, Matsui M, Mizushima N. Autophagy 2007; 3:323-8). Therefore, as a negative control, we investigated a mutant human LC3DeltaG protein in which the C-terminal Gly(120) essential for LC3-lipidation is deleted, and generated a set of expression plasmids for wild-type human LC3 and mutant LC3DeltaG fused to either CFP, GFP, YFP, or HcRed at the N terminus. We found that the mutant LC3DeltaG protein does not react with human Atg7 and Atg3, indicating that LC3-lipidation does not occur, and few puncta containing mutant LC3DeltaG form under starvation conditions. As observed with wildtype HcRed-LC3, mutant HcRed-LC3DeltaG also co-localizes with polyQ150-aggregates suggesting that the colocalization of HcRed- LC3 to polyQ150-aggregates is independent of LC3-lipidation. These mutant LC3DeltaG proteins will be useful negative controls in recognizing non-specific fluorescent protein-LC3 aggregates.  相似文献   
538.
The solvent extraction properties of macrocyclic trinuclear organometallic complexes, [(p-cymene)Ru(pyO2)]3 and [CpRh(pyO2)]3, for Li+, Na+, and K+ picrates have been investigated in a dichloromethane-water system at 25 °C. The extraction rates of the alkali metal picrates with these macrocyclic complex ligands are unusually slow; the shaking times required to attain equilibrium are at least 1 h for [(p-cymene)Ru(pyO2)]3 and 20-40 h for [CpRh(pyO2)]3. From analysis of the equilibrium data, the extraction constants (Kex = [ML+A]o/[M+][L]o[A]; M+ = alkali metal ion, L = macrocyclic ligand, A = picrate ion, o = organic phase) have been determined. The log Kex value varies in the sequences, Li+ (5.72) > Na+ (4.50) > K+ (2.88) for [(p-cymene)Ru(pyO2)]3 and Li+ (4.79) > Na+ (2.70) ≈ K+ (2.69) for [CpRh(pyO2)]3. The Kex values of 6,6-dibenzyl-14-crown-4 (DBz14C4), which is one of the best Li+-selective crown ethers, have also been determined for comparison. It is revealed that [CpRh(pyO2)]3 is much superior to DBz14C4 both in the extractability for Li+ and the selectivity for Li+ over Na+.  相似文献   
539.
540.
Recently, we reported potent BACE1 inhibitors KMI-429, -684, and -574 possessing a hydroxymethylcarbonyl isostere as a substrate transition-state mimic. These inhibitors showed potent inhibitory activities in enzymatic and cell assays, especially, KMI-429 was confirmed to significantly inhibit Abeta production in vivo. However, acidic moieties at the P(4) and P(1)' positions of KMI-compounds were thought to be unfavorable for membrane permeability across the blood-brain barrier. Herein, we replaced acidic moieties at the P(4) position with other hydrogen bond acceptor groups, and these inhibitors exhibited improved BACE1 inhibitory activities in cultured cells. In this study, we replaced the acidic moieties at the P(1)' position with non-acidic and low molecular sized moieties.  相似文献   
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