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1.
A radical chain addition of allyl bromides 2 to alkenylcyclopropanes 1 resulted in [3+2] annulation to give 2-bromomethylalkenylcyclopentanes 3 in good yields(16 examples). In this reaction, two kinetically fast radical reactions, cyclopropylcarbinyl radical-ring-opening and 5-exo-radical cyclization, preceded the β-fragmentation of a bromine radical to make the formal cycloaddition possible.  相似文献   
2.
Purpose: The obstacle negotiation gait (ONG) is a fundamental activity of daily living. In cerebrovascular hemiplegic patients (stroke patients), the weight-bearing rate (WBR) on the paretic limb necessary for an independent ONG was studied. Methods: One hundred and seventeen stroke patients were involved. The patients'' average age at the time of the study was 67 years, and the average time from stroke onset was 102 days. There were 68 men and 49 women. Seventy patients were right hemiplegics, and 47 were left hemiplegics. The correlations between ONG and age, sex, body mass index (BMI), time from stroke onset, muscle strength of both the paretic and non-paretic limbs, Brunnstrom stage of the lower limbs, deep sensation, and the WBR on both the paretic and non-paretic limbs were studied. Patients who could perform ONG independently and safely were categorized as the independent group (IG), and those who needed observation or any assistance were categorized as the dependent group (DG). Results: The BMI, muscle strength of both the paretic and non-paretic limbs, Brunnstrom stage of the lower limbs, deep sensation and the WBR for both the paretic and non-paretic limbs were significantly different between the IG and DG groups. In particular, the WBR on the paretic limb was found to correlate significantly with the ONG, and a WBR value of 80.5% on the paretic limb gave a clear cut-off value. Conclusion: Although multiple factors influenced the ONG of stroke patients, the WBR on the paretic limb was the most influential.  相似文献   
3.
New types of selective estrogen receptor modulators (SERMs) were synthesized and evaluated for their binding affinity and biological effect on reproductive cells. A proposed lead structure (B) was derivatized to provide compounds 30 and 44, which showed good estrogen-receptor binding affinity (K(i) values: 6.3 and 10 nM, respectively), as well as minimal impact on mammary and uterine carcinoma cells. Introduction of an alkyl group in the core structure considerably enhanced receptor-binding affinity of the compounds tested. Synthesis and structure-activity relationships of these compounds are described.  相似文献   
4.
5.
G-phase precipitation in the ferrite phase in thermally aged duplex stainless steel (DSS) was investigated. A needle-shaped sample of DSS aged at 673?K for 5000?h was observed by transmission electron microscopy (TEM), and subsequently by atom probe tomography (APT). The precipitates of the G-phase observed by TEM corresponded well to clustering atoms observed by APT. On the other hand, regarding the precipitates of the G-phase that formed in an earlier stage of aging, the present study suggests that not all the precipitates can be detected by TEM. A large area of DSS aged at 673?K for 5000?h containing both the ferrite and austenite phases was observed. The number density of precipitates of the G-phase in the ferrite phase was small in the vicinity of the phase boundary and increased with the distance between the phase boundary and each field of view. The number density reached an almost constant value at a distance of approximately 4?µm from the phase boundary. The suppression of G-phase precipitation in the vicinity of the phase boundary is discussed in terms of the depletion of alloying elements that comprise the G-phase.  相似文献   
6.
The effects of Mo on precipitation behaviours in aged cast stainless steels have been investigated. Mo-free CF3 steel and Mo-bearing CF3M steel, both of which consisted of a duplex structure of ferrite and austenite phases, were prepared. Microstructural evolution in the ferrite phase during ageing at 723 K has been observed by transmission electron microscopy (TEM). Precipitates in CF3 steel were identified to belong to the G-phase and possess lattice coherency with the ferrite phase at interphase boundaries. On the other hand, precipitates in CF3M steel were found to be nanodomains of not only to the G-phase but also to another phase enriched in Mo. Some of the nanodomains containing Mo exhibited diffraction patterns having pseudo five-fold symmetry, but others exhibited regular periodicity in high-resolution TEM images. The atomic structure of the Mo-related nanodomains is proposed to be a distorted χ-phase that retains coherency with the matrix.  相似文献   
7.
Characterization of an ultra-low loss and high finesse Fabry-Perot cavity at 1064 nm is reported. The characteristics are obtained from measurements of cavity decay time, frequency response and transmission efficiency. The results show that the mirrors have the loss of 1.5 ppm including absorption and scattering losses and the reflectance of 99.9873% which corresponds to a cavity finesse of 2.48X104.  相似文献   
8.
Measurement of autoradiographic grains produced by the decay of incorporated radioisotopes is often used for a quantitative assay of the rate of DNA replication and DNA repair in cells or tissues. However, visual grain counting by microscopic observation is time-consuming and tedious process. Recently, Kraemer et al. reported that automated measurement of grains in cultured human cells may be facilitated by using appropriate grain counting instruments. Under their experimental conditions using Kodak NTB-3 emulsion, instrument-determined grain number per nucleus was proportional to visual counts up to 30 grains, and then leveled off at much larger visual counts. The saturation phenomenon was due to counting-loss by the instrument caused by overlapping of neighboring grains. To prevent the counting-loss, we have used in the present study Japanese Sakura NR-M2 emulsion which is less sensitive to radiation exposure than Kodak NTB-3, thereby yielding smaller size of grains per radioactive decay. Samples were prepared from cultured skin fibroblasts derived from normal individuals and xeroderma pigmentosum (XP) patients defective in DNA repair. These cells were irradiated with 254 nm UV incubated for 3 h with culture medium containing 3H-thymidine, and autoradiograms were made by dipping in Sakura NR-M2 emulsion. The number of grains as well as grain surface area per nucleus was measured by using ARTEK CYTO TALLY MODEL 900 counting instrument, and compared with visual counts. The results showed that, under our optimum condition, the instrument-determined number of grains was directly proportional to visual counts, at least up to 150 grains per nucleus, with a correlation coefficient of 0.971.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
N-Phenylated aromatic polyamide-esters with high molecular weights were synthesized by the high-temperature solution polycondensation in nitrobenzene at 200°C from combinations of m- and p-anilinophenol and isophthaloyl and terephthaloyl chloride. Reaction variables such as monomer concentration, solvent, temperature, and time were studied to optimize the reaction conditions for the preparation of high molecular weight polymers. Some of the N-phenylated aromatic polyamide-esters have glass transition temperatures around 190°C and good solubility in chlorinated and amide solvents. These polymers gave transparent flexible films by solution-casting. Copolymers from p-anilinophenol and the two diacid chlorides were also synthesized and characterized.  相似文献   
10.
The forearm muscles of five healthy males were monitored for changes in microvessel hemoglobin saturation (SO2-TRS) by near infrared time-resolved spectroscopy (NIRTRS) and changes in phosphorus metabolites by magnetic resonance spectroscopy (31P-MRS) during 12 min of resting arterial occlusion. Muscle oxygenation and phosphorus metabolites were also measured during grip exercises at varying intensities. Upon the initiation of occlusion, SO2-TRS fell progressively until it reached a plateau in the latter half of the occlusion. Phosphocreatine (PCr) began to decrease around 6 min after the initiation of arterial occlusion. The resting O2 store and O2 consumption were 295 μM and 0.95 μM/sec, respectively-values which reasonably agree with the reported results. A significant correlation was observed between the changes in SO2-TRS and PCr during exercise (r2 = 0.80, p < 0.001). These results indicate that NIRTRS is able to provide reliable information about resting metabolism and oxidative rate during exercise. NIRTRS and MRS are useful to monitor oxygenation and energetics noninvasively in the human muscle.  相似文献   
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