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151.
The objective of the study was to assess the usefulness of magnetic resonance (MR) imaging in distinguishing malignant from benign conditions in patients with an abnormal uterine cavity. Fifty-four patients that were suspected of having abnormal uterine cavities were retrospectively evaluated by using MR imaging. The diagnosis of an abnormal uterine cavity included a thickened endometrium, and/or a endometrial mass, and/or a submucosal mass. Threshold values to classify the uterine cavity as abnormal on sagittal T2-weighted images were >10 mm for premenopausal women and >5 mm for postmenopausal women. Malignancy was diagnosed when lesions invaded the myometrial/junctional zone, and/or lesion enhancement was lower than that of the adjacent myometrium. The results found that histology confirmed 18 malignant and 37 benign lesions. Twelve of 15 endometrial carcinomas and 3 malignant mixed mesodermal tumors (MMMT) were correctly characterized as malignant on enhanced T1-weighted images; whereas 6 of 15 endometrial carcinomas and 3 MMMT were correctly characterized on T2-weighted images. Thirty-four of 37 benign cases were correctly characterized as not malignant on enhanced T1-weighted images. One of 14 submucosal leiomyomas, one endometrial stromal metaplasia, and one of ten pathologically normal endometria were misdiagnosed on enhanced T1-weighted images but were correctly diagnosed on T2-weighted images. The overall sensitivity, specificity, and accuracy for distinguishing malignant from benign central uterine masses were 83%, 92%, and 89% for enhanced T1-weighted image, and 50%, 97%, and 82% for T2-weighted image, respectively. We came to the conclusion that in diagnosing patients with abnormal uterine cavity, MR imaging may help differentiate malignant from benign disorders.  相似文献   
152.
We describe transfer carbonylation reactions of 2‐bromoarenes that contain a carbon‐nucleophile using aldehydes as a substitute for CO, leading to the formation of indanone derivatives. The transformation proceeds efficiently under RhI/Pd0‐hybrid catalytic conditions consisting of two discrete transition metals, rhodium and palladium, which catalyze the decarbonylation of aldehydes and the subsequent carbonylation of bromoarenes using the resulting carbonyl moiety, respectively. The majority of the abstracted CO is transferred directly to the product via a CO‐relay process from rhodium to palladium.  相似文献   
153.
Phenyl- and vinyllithiums having an alkyl substituent at their ortho- and cis-position, respectively, readily added to alkynes in the presence of 5 mol% of Fe(acac)(3). The reaction of o-(trimethylsilyl)phenyllithium with alkynes gave benzosiloles through an addition-cyclization sequence.  相似文献   
154.
A novel chiral menthol derivative supported on silsesquioxane was easily synthesized by hydrosilylation of the corresponding arylmenthyl olefin with commercially available silsesquioxane-type hydrosilane. We evaluated the applicability of the silsesquioxane-based compound to diastereoselective [2+2] photocycloaddition reaction. The newly synthesized silsesquioxane-based chiral menthol derivative 9 indicated similar diastereoselectivity to the corresponding p-methoxyphenyl menthol derivative.  相似文献   
155.
Saponite-type clays that have different cation exchange capacities were successfully synthesized by hydrothermal synthesis. The structure and properties were analyzed by X-ray diffraction, X-ray fluorescence, (27)Al NMR, FT-IR, thermogravimetric and differential thermal analysis, atomic force microscopy, and cation exchange capacity measurement. The intercharge distances on the synthetic saponite (SS) surfaces were calculated to be 0.8-1.9 nm on the basis of a hexagonal array. The complex formation behavior between SS and cationic porphyrins was examined. It turns out that the average intermolecular distance between porphyrin molecules on the SS surface can be controlled, depending on the charge density of the SS. In the case of tetrakis(1-methylpyridinium-4-yl)porphyrin (H(2)TMPyP(4+)), the average intermolecular distances on the SS surface can be controlled from 2.3 to 3.0 nm on the basis of a hexagonal array. It was also found that absorption maxima of porphyrins depend on the charge density of the SS. The adsorption behavior of porphyrin on the SS surface can be rationally understood by the previously reported "size-matching rule". This methodology using host-guest interaction can realize a unique adsorption structure control of the porphyrin molecule on the SS surface, where the gap distance between guest porphyrin molecules is rather large. These findings will be highly valuable to construct photochemical reaction systems such as energy transfer in the complexes.  相似文献   
156.
We have measured the buckling, B1g, phonon mode of optimally doped, de-twinned, YBa2Cu3O7−δ using inelastic X-ray scattering (IXS) at BL35XU of SPring-8. Measurements of this mode, which has atomic motion transverse to the Cu-O planes, serve to demonstrate some of the advantages of the unique two-dimensional (2-D) analyzer array at BL35. Analysis based on fitting the entire spectra simultaneously at 10 and 100 K shows that the buckling mode is rather broad in the middle of the zone (near (0.3 0 0)). We see a consistent softening of the mode at 10 K as compared to 100 K for all measured wave-vectors (h 0 0), and a q-dependent softening as zone center is approached.  相似文献   
157.
Angle-resolved photoemission spectroscopy with low-energy tunable photons along the nodal direction of oxygen isotope substituted Bi(2)Sr(2)CaCu(2)O(8+delta) reveals a distinct oxygen isotope shift near the electron-boson coupling "kink" in the electronic dispersion. The magnitude (a few meV) and direction of the kink shift are as expected due to the measured isotopic shift of phonon frequency, and are also in agreement with theoretical expectations. This demonstrates the participation of the phonons as dominant players, as well as pinpointing the most relevant of the phonon branches.  相似文献   
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