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11.
Isolation and structure elucidation of further new saponins from Solidago canadensis] 总被引:4,自引:0,他引:4
G Reznicek J Jurenitsch M Freiler S Korhammer E Haslinger K Hiller W Kubelka 《Planta medica》1992,58(1):94-98
Four new main saponins (canadensis-saponins 5-8) (compounds 5-8) were isolated from Solidago canadensis L. (Asteraceae). Using GC/MS, FAB-MS, and mainly 2D-NMR techniques their structures were identified as 3-O-[beta-D-glucopyranosyl(1----3)-beta-D- glucopyranosyl]-28-O-[beta-D-galactopyranosyl(1----2)-alpha-L- rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[beta-D-apio -D- furanosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl-(1----)]-bayog enin(5),3-O- [beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-O-[beta-D- galactopyranosyl-(1----2)-alpha-L-rhamnopyranosyl-(1----3)-beta-D- xylopyranosyl-(1----4)-[beta-D-xylopyranosyl-(1----3)]-alpha-L- rhamnopyranosyl-(1----2)-[beta-D-apio-D-furanosyl-(1----3)]- arabinopyranosyl-(1----)]bayogenin(6),3-O-[beta-D-glucopy ran osyl-(1----3)- beta-D-glucopyranosyl]-28-O-[beta-D-galactopyranosyl-(1----2)- alpha-L-rhamnopyranosyl-(1----3)-beta-D-xylopyranosyl-(1----4)-[beta-D- xylopyranosyl-(1----3)]-alpha-L-rhamnopyranosyl-(1----2)-[alpha-L- rhamnopyranosyl-(1----3)]-beta-D-6-deoxyglucopyranosyl-(1----)]-++ +bayogenin (7), and 3-O-[beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranosyl]-28-[O- beta-D-galactopyranosyl-(1----2)-alpha-L-rhamnopyranosyl-(1----3)-beta-D - xylopyranosyl-(1----4)-[beta-D-xylopyranosyl-(1----3)]-alpha-L- rhamnopyranosyl-(1----2)-[alpha-L-rhamnopyranosyl-(1----3)]arabinopyr anosyl - (1----)[-bayogenin (8). 相似文献
12.
In the differentiated state, the testicular excurrent duct system of the sturgeon begins as a longitudinal marginal network of the testis, extending along the entire length of the male gonad. From here, mesorchial transversal ducts travel to the ventral aspect of the pars sexualis of the opisthonephros where they merge behind the dorsal coelomic wall to form the longitudinal marginal network of the kidney. Then, the seminal pathways enter the confines of the pars sexualis of the opisthonephros and divide into a complicated, multipartite system consisting of (1) centropapillary ducts, situated in the center of a group of urinary collecting ducts, (2) lacunary basal sinuses, located on the bases of opisthonephric columns and (3) intracolumnar ducts running inside the renal columns, the latter representing typical functional units of the adult sturgeon kidney. The contacts between intracolumnar ducts and the vascular poles of corresponding renal corpuscles represent the urogenital junction in the sturgeon. The nephrons of the pars sexualis involved in sperm transport do not lose their urinary functions, but are histologically identical to those of the pars excretoria which are solely urinary. The opisthonephros of sturgeons grows continuously by the formation of new nephrons from an opisthonephric blastema located on the base of each renal column. A close topographical association between this blastema tissue and the lacunary basal sinuses of the testicular excurrent duct system guarantees that new renal corpuscles in the pars sexualis are included in the seminal passage from their beginning. From the urogenital junctions, on their way to the exterior, the spermatozoa have to travel through Bowman's capsules and tubules of the nephrons involved, then through the urinary collecting ducts, the wolffian duct and finally the sinus urogenitalis. The development of the testicular excurrent duct system begins in 8-month-old animals in the pregonadal area of the gonadal fold. Here, a primary gonoductal blastema proliferates to form a longitudinal network of anastomosing strands, situated in the dorsal mesogonadal attachment. From this primary longitudinal network, small tubules grow into the direction of the opisthonephros and into the direction of the testis. In the period from 8 to 18 months, the testicular excurent duct system reaches the adult state. In conclusion, the testicular excurrent ducts of sturgeons initially develop similar to those of Polypterus and in modern teleosts from a primary longitudinal system, beginning in the pregonadal area, localized in the mesogonadal attachment and extending caudally. Then, in a second step of development, the phylogenetically older situation, using parts of the kidney as passage, already seen in Chondrichthyes, but preserved also in higher vertebrates, is achieved in Acipenser. For this, seminal ducts grow into the opisthonephros and establish here the urogenital junctions with corresponding renal corpuscles. Furthermore, the initially longitudinally oriented ducts in the mesogonadal attachment partly lose their continuity and become integrated into the course of the transversal mesorchial ducts, represented by their portions with the widest lumina and the thickest walls. 相似文献
13.
Michael Schwarz Frank Block Rudolf Tpper Karl-Heinz Sontag Johannes Noth 《Annals of neurology》1992,32(3):358-364
Intrastriatal injection of quinolinic acid (QA) in rats provides an animal model that mimics some of the neuropathological and neurochemical alterations observed in the striatum of patients with Huntington's disease (HD). One of the very early neurophysiological signs in HD is a diminution of amplitude of early somatosensory evoked potentials (SEPs) recorded over the parietal cortex. The present study investigated whether the QA model exhibits similar neurophysiological abnormalities. Two weeks after unilateral intrastriatal injection of QA (240 nmol) or of the solvent, early SEPs were recorded with chronically implanted electrodes from the somatosensory cortex or from the ventrobasal nucleus of the thalamus of lightly pentobarbital-anesthetized rats, in response to single-shock electrical stimulation of the contralateral forepaw. Whereas intrastriatal injection of solvent did not influence SEPs, the striatal QA lesion significantly reduced the amplitude of early cortical SEPs by about 40% without affecting the latency. SEPs recorded from the ventrobasal nucleus were unchanged after QA lesion. Histological examination and glial fibrillary acid protein staining after intrastriatal injection of QA revealed no evidence for damage in the somatosensory system. It is concluded that (1) the QA animal model of HD mimics some of the SEP abnormalities of patients, and (2) a striatal lesion modulates somatosensory transmission to the cortex in rats. 相似文献
14.
Balance and recovery from a perturbation are impaired in people with functional ankle instability. 总被引:1,自引:0,他引:1
Claire E Hiller Kathryn M Refshauge Robert D Herbert Sharon L Kilbreath 《Clinical journal of sport medicine》2007,17(4):269-275
OBJECTIVE: To determine if differences in balance and recovery would be found between controls and participants with unilateral or bilateral functional ankle instability (FAI). DESIGN: Cross-Sectional Study. SETTING: University laboratory and Community premises. PARTICIPANTS: Twenty healthy participants(C), 19 participants with unilateral FAI [both the uninjured (UC) and unstable ankle (UI) were included] and 22 participants with bilateral FAI (BI). MAIN OUTCOME MEASURES: Balance was measured in single leg stance as: number of part foot lifts in 30 s; magnitude of medio-lateral ankle movement in two foot positions; and ability to balance on the ball of the foot. Recovery was determined by time to return to baseline medio-lateral ankle movement after a 15 degree inversion perturbation. RESULTS: The controls lifted the foot fewer times than the other three groups [C = 12.7 +/- 1.8 (mean +/- SE) foot lifts, UC = 22.9 +/- 2.5, UI = 25.1 +/- 2.3, and BI = 21.1 +/- 2.2, t-test, P = 0.006] and recovered significantly faster than the unstable ankles [C = 1.53 +/- 0.42 sec (median +/- SE), UI = 2.34 +/- 0.30 sec, BI = 2.15 +/- 0.70 sec, P < 0.02]. With FAI measured by the Cumberland Ankle Instability Tool, the external control group balanced on demi-pointe better than both instability groups (P < 0.05), and recovered quicker than all groups. CONCLUSION: There are differences in balance and recovery between external controls and participants with both unilateral and bilateral FAI but not between the legs of participants with unilateral FAI. 相似文献
15.
Epidemiologic associations with nuclear, cortical, and posterior subcapsular cataracts 总被引:6,自引:0,他引:6
Data from the 1971-1972 National Health and Nutrition Examination Survey were used to examine the associations between specific cataract types and age, race, sex, number of years spent in school, diabetes, systolic blood pressure, urban versus rural residence, and average daily ultraviolet spectrum B (UV-B) radiation counts at the site of examination. Separate comparisons were made of persons with no lens changes (n = 1,299) and persons with cortical (n = 55), nuclear (n = 104), and posterior subcapsular cataracts (n = 18). Persons with more than one type of cataract were excluded from the analysis. Cortical cataracts were associated with age (relative risk (RR) = 11.4 for age 70 years vs. age 50 years), race (RR = 3.5 for blacks vs. whites), sex (RR = 3.0 for women vs. men), educational achievement (RR = 1.8 for less than nine years of schooling vs. college), and UV-B count (RR = 3.6 for 6.0 X 10(3) counts vs. (2.6 X 10(3) counts). Nuclear cataracts were associated with age (RR = 38.6 for age 70 years vs. age 50 years), race (RR = 1.8 for black vs. white), and residence (RR = 1.6 for rural vs. urban). Posterior subcapsular cataracts were associated with diabetes (RR = 6.6 for diabetes present vs. diabetes absent) and systolic blood pressure (RR = 2.2 for 160 mmHg vs. 120 mmHg). Cortical cataracts were more common in women and more often found in locations with increased UV-B radiation counts than either nuclear or posterior subcapsular cataracts. In diabetics, the risk of posterior subcapsular cataracts was greater than the risk of nuclear cataracts (p less than 0.05) and also appeared to be greater than the risk of cortical cataracts (p = 0.06). 相似文献
16.
There is some controversy over the treatment of acromioclavicular injuries. The use of the Rockwood classification as the basis for decisions on whether operative or nonoperative treatment is indicated is discussed critically, and the authors' preferred operative technique is described and illustrated by examples. We treat injuries classified according to the Rockwood classification as types I and II with conservative methods. In type III injuries the patient's age, job and free time activities determine whether or not surgery is indicated. In the case of type IV or type VI injuries we always perform temporary internal fixation of the acromioclavicular joint, using transarticular K-wire fixation or hookplate osteosynthesis. Satisfactory results of both operative and nonoperative treatment are reported in the literature. The authors' own results are presented. 相似文献
17.
Fckhard Jhde Karl-Heinz Geüsenkamp Manfred F. Rajewsky 《International journal of cancer. Journal international du cancer》1989,44(6):1082-1087
The sensitivity of a cyclophosphamide (CP)-resistant MIR rat mammary carcinoma cell variant (MIRCPr) in monolayer culture towards the cytotoxic effect of mafosfamide (an analogue of "activated" CP) was measured as a function of extracellular pH (pHe). An inverse correlation was found between cell survival and the H+ ion concentration in the culture medium. At pHe 7.4, the fraction of clonogenic MIRCPr cells exposed to mafosfamide (7.5 micrograms/ml) for 24 hr was 1 X 10(-1) in relation to untreated control cells. At pHe 6.2, however, this value was reduced to 3 X 10(-4), i.e., a value equal to that for the CP-sensitive parental MIR cells exposed to the same concentration of mafosfamide at pHe 7.4. Our data indicate complete compensation of CP resistance in MIRCPr cells at pHe 6.2. MIRCPr cells were not resistant to the cytotoxic effect of nornitrogen mustard. This suggests that resistance to CP in MIRCPr cells is due to enzymatic inactivation of the primary intermediates in CP bioactivation. The alkylating activity of nornitrogen mustard (and less so that of phosphoramide mustard) is strongly enhanced at low pH. In MIRCPr cells shifted to an acidic environment, therefore, a (putative) decrease in the intracellular concentration of alkylating CP metabolites may be counteracted by an enhancement of their alkylating activity (on a molar basis). By parenteral administration of glucose, the pH in malignant tumors of both animal and human origin can be lowered to values between 5.6-6.6. Our data suggest that an upshift of H+ ion concentration in malignant tissues may at least partially counteract CP resistance in cancer cells in vivo. 相似文献
18.
M. Gietz W. Mempel Ch. Clemm E. Hiller M. Heim W. Wilmanns 《Journal of molecular medicine (Berlin, Germany)》1988,66(14):633-638
Summary
51Cr-platelet kinetic studies were performed in 77 patients with idiopathic thrombocytopenic purpura. The sequestration site was splenic for 63, splenic/hepatic for 7 or hepatic for remaining 7 patients. In 20 patients platelet survival was extremely shortened to 0–3 h, whereas only 26 patients had a survival time of more than 24 h. Those patients with low platelet counts also had a very short platelet survival time, whereas patients with higher platelet counts (>50×109/l) had longer platelet survival times. 51 patients (66%) were splenectomized following the kinetic studies. 25 patients who had a splenic sequestration site had normalized platelet counts and 6 patients had platelet counts between 80–149×109/l 12 months after splenectomy (i.e. in 92% of cases with splenic sequestration site a full or partial remission). Of the 11 patients with a hepatic or splenic/hepatic sequestration site, 2 patients had full remission, 1 partial remission, 3 patients had minimal improvement and 5 other patients were treatment failures in respect to the splenectomy.
Abkürzungen ACD-A Acid-Citrat-Dextrose Lösung A - HBsAge Hepatitis-B Oberflächen-Antigen - ITP idiopathische thrombozytopenische Purpura - PAIgG plättchenassoziierte IgG-Antikörper - TRP thrombozytenreiches Plasma 相似文献
Abkürzungen ACD-A Acid-Citrat-Dextrose Lösung A - HBsAge Hepatitis-B Oberflächen-Antigen - ITP idiopathische thrombozytopenische Purpura - PAIgG plättchenassoziierte IgG-Antikörper - TRP thrombozytenreiches Plasma 相似文献
19.
Rudolf Ernst Lang Karl-Heinz Voigt Horst Lorenz Fehm Ernst Friedrich Pfeiffer 《Neuroscience letters》1976,2(1):19-22
Hypothalamic nuclei were removed from frozen sections of rat brain and examined for their corticotropin-releasing activity. The highest concentration was measured in the median eminence. In addition there was significantly more activity detected in the nuclei paraventricularis, supraopticus, suprachiasmaticus and arcuatus than in the other nuclei. 相似文献
20.
Frank Wiedemann Ralf Link Konrad Pumpe Ulrich Jacobshagen Hans E. Schaefer Karl-Heinz Wiesmüller Rolf-Peter Hummel Günther Jung Wolfgang Bessler Traudel Bltz 《The Journal of pathology》1991,164(3):265-271
The inflammatory reactions following subcutaneous application of adjuvants revealed characteristic pathological patterns. The injection of complete Freund's adjuvant (CFA) resulted in the formation of large lipid deposits encircled by an inflammatory reaction and concentrically arranged collagen bundles. Bacterial lipopolysaccharide (LPS) caused granulomatous aggregations of mononuclear cells with thrombotic vessel occlusions. Inoculation of the lipopeptide adjuvants induced accumulation of mononuclear cells with only minimal fibrotic changes which were resolved after day 28. Lipopeptide conjugates based on the head group tripalmitoyl-S-glyceryl-cysteinyl-serin (P3CS) can thus be used as effective immunogens and adjuvants without long-term tissue damage. 相似文献