排序方式: 共有93条查询结果,搜索用时 15 毫秒
71.
Trillos D Krajcer Z Lufschanowski R Leachman RD Klima T Cooley DA 《Cardiovascular diseases》1980,7(1):95-103
A 55-year-old man was referred for the evaluation of frequent chest pain and syncope. While in the hospital, he experienced severe chest pain accompanied by transient ST segment elevation and a slight elevation of cardiac enzyme levels. Multiple coronary arteriograms were recorded at various times during an interval of 2 months. On one occasion, the results were normal; on another occasion, they showed total occlusion of the left anterior descending, diagonal, and circumflex coronary arteries. The occlusion was completely relieved with sublingual nitroglycerin. Because the patient's clinical condition deteriorated rapidly, double aortocoronary saphenous vein bypass was performed to the left anterior descending and circumflex coronary arteries. During the induction of anesthesia, ventricular fibrillation occurred, and the patient died from refractory recurrent fibrillation 4 hours after surgery. Postmortem examination revealed normal coronary arteries, patent vein grafts, and multiple focal areas of recent and old myocardial fibrosis. Thus, it appears that coronary spasm, in the presence of otherwise normal coronary arteries, can produce myocardial infarction with necrosis, and that medical management may provide a more successful method of treating such patients. 相似文献
72.
Margetić P Miklić D Rakić-Ersek V Doko Z Lubina ZI Brkljacić B 《Collegium antropologicum》2007,31(1):279-284
The purpose of the study was to assess the value of ultrasonography in the diagnosis of Achilles tendon rupture, by comparing initial ultrasonographic scans and direct intraoperative findings, as well as to follow up the healing process in operatively and conservatively treated patients. Ultrasound examination was performed in 100 patients (91 males and 9 females, with mean age of 46 years) with clinically suspicious Achilles tendon ruptures. Ultrasonographic findings were compared with intraoperative findings. Eighty-eight patients underwent surgery and twelve patients were treated conservatively. Complete ruptures were diagnosed by ultrasound in 88 patients, and partial ruptures in 12 patients. The length of the tendon (Pearson r = 0.973, p < 0.001, Spearman p = 0.972, p < 0.001) and the size of the rupture (Pearson r = 0.940, p < 0.001, Spearman p = 0.905, p < 0.001) measured before surgery by ultrasound and directly during surgery showed a high correlation. Out of 88 operatively treated patients, 86 had a complete rupture and two had a partial rupture. All patients were examined 3, 5, 8, and 12 weeks after injury or after surgery. In the first five weeks, there were statistically significant differences noted between these two groups. Operatively treated tendons healed more quickly, but after eight and twelve weeks this difference had disappeared. Our study showed that ultrasound is an excellent imaging method for confirming the clinical diagnosis of Achilles tendon rupture as well as for following up the process of tendon healing. 相似文献
73.
Acetylation of the hydroxyl group in 20α-hydroxy-4--pregnen-3-one decreases the binding capacity of the molecule to transcortin to only 1% of that of progesterone. By this simple procedure it is possible to eliminate the influence of 20α-hydroxy-4-pregnen-3-one in determinations of progesterone concentrations by the competitive protein--binding method, which is highly desirable when a great number of samples are analyzed. 相似文献
74.
Acta Biotheoretica - The emphasis on the organization of entities and their activities and interactions has been labeled one of the most distinct contributions of mechanistic philosophy. In this... 相似文献
75.
Chemical analysis of Asphodelus microcarpus Salzm. et Viv. honey is of great importance, since melissopalynology does not allow the unambiguous determination of its botanical origin. Therefore, the volatile compounds of eight unifloral asphodel honeys have been investigated for the first time. The honey extracts were obtained by headspace solid-phase microextraction (HS-SPME) and ultrasonicsolvent extraction (USE) and analyzed by GC and GC/MS. In the honey headspace, 31 volatile compounds were identified with high percentages of 2-phenylacetaldehyde (2; 14.8–34.7%), followed by somewhat lower percentages of methyl syringate (1; 10.5–11.5%). Compound 2 is not a specific marker of the botanical origin of the honey, but its high percentage can be emphasized as headspace characteristic of asphodel honey. The extraction solvent for all the samples was selected after extracting a representative sample with pentane, Et(2)O, pentane/Et(2)O 1:2 (v/v), and CH(2)Cl(2) . Compound 1 was the major constituent of all the USE extracts (46.8–87.0%). According to these preliminary results, all the honey samples were extracted by USE with the solvent pentane/Et(2)O 1:2. A total of 60 volatile compounds were identified with 1 as predominant compound (69.4–87.0%), pointing out 1 as Asphodelus honey volatile marker. 相似文献
76.
Maja Crkvenčić Slavica Dudaš Igor Jerković Zvonimir Marijanović Danijela Poljuha Kroata Hazler Pilepić 《化学与生物多样性》2016,13(2):219-223
The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of Globularia cordifolia L., G. meridionalis (Podp.) O.Schwarz , and G. punctata Lapeyr . was characterized by GC‐FID and GC/MS analyses. Among the 33 identified compounds, the most abundant present in all investigated samples were oct‐1‐en‐3‐ol (2.9–47.0%), 6‐(1,5‐dimethylhex‐4‐enyl)‐3‐methylcyclohex‐2‐enone (8.2–40.9%), and fukinanolid (7.4–31.6%). Multivariate statistical analyses (PCA and HCA) of the hitherto studied Globularia volatile compounds confirmed to some extent the assumed phylogenetic relationships of the Globularia species studied, including the close relationship between the morphologically similar species G. cordifolia and G. meridionalis, but also evidenced several discrepancies in the current classification of Globularia species. 相似文献
77.
Susan A. Austin Anantha Vijay R. Santhanam Livius V. d’Uscio Zvonimir S. Katusic 《PloS one》2015,10(12)
The hippocampus is one of the earliest and most affected regions in Alzheimer’s disease (AD), followed by the cortex while the cerebellum is largely spared. Importantly, endothelial dysfunction is a common feature of cerebral blood vessels in AD. In this study, we sought to determine if regional heterogeneity of cerebral microvessels might help explain the susceptibility of the hippocampus and cortex as compared to the cerebellum. We isolated microvessels from wild type mice from the cerebellum, cortex, and hippocampus to characterize their vascular phenotype. Superoxide anion was significantly higher in microvessels isolated from the cortex and hippocampus as compared to the cerebellum. Importantly, protein levels of NADPH oxidase (NOX)-2 and NOX-4 were significantly higher in the cortical and hippocampal microvessels as compared to microvessels from the cerebellum. In addition, expression of manganese superoxide dismutase protein was significantly lower in microvessels from the cortex and hippocampus as compared to cerebellum while other antioxidant enzymes were unchanged. There was no difference in eNOS protein expression between the microvessels of the three brain regions; however, bioavailability of tetrahydrobiopterin (BH4), an essential cofactor for eNOS activity, was significantly reduced in microvessels from the hippocampus and cortex as compared to the cerebellum. Higher levels of superoxide and reduced tetrahydrobiopterin bioavailability may help explain the vulnerability of the hippocampus and cortical microvessels to oxidative stress and development of endothelial dysfunction. 相似文献
78.
Zusammenfassung Es wurde festgestellt, daß eine kurze Vorbelichtung (1–30 min) etiolierter Bohnenkeimlinge, die durch die -Bestrahlung hervorgerufene Verzögerung der Granaentwicklung deutlich herabsetzt. Da beim unbestrahlten etiolierten Material die gleiche Vorbelichtung eine Beschleunigung der Granabildung hervorruft, wird der Schluß gezogen, daß es sich bei der beobachteten Erscheinung um keinen Schutz-oder Restaurationseffekt handelt, sondern um einen photomorphogenen Effekt, der selbst von der -Strahlung unabhängig ist.
The effect of pre-illumination on the development of plastids in primary leaves of -irradiated etiolated bean seedlings
Summary It has been shown that a short pre-illumination (1–30 min) of etiolated bean seedlings considerably reduces the delay of grana development in the plastids caused by gamma radiation. As in non-irradiated etiolated material the grana formation is stimulated by an equal pre-illumination, it may be concluded that the observed phenomenon is not a consequence of protection or restoration processes but of a photomorphogenic effect which is independent even of gamma radiation.相似文献
79.
Flowering under experimental conditions inSpirodela polyrrhiza, and the development of the spatha, stamina and pistil are described and illustrated by microphotographs. During the development of the microsporangia the existence of the middle layer between endothecium and tapetum has been documented for the first time inLemnaceae. 相似文献
80.
A patient with aortic regurgitation, stenosis, and calcification of the septum is reported. Results of echocardiography revealed asymmetrical septal hypertrophy without other features of idiopathic hypertrophic subaortic stenosis. There was no subaortic obstruction evident on cardiac catheterization and angiography. This case serves to emphasize that calcification of the interventricular septum is another possible cause of asymmetrical septal hypertrophy. 相似文献