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We describe a middle-aged Chinese systemic lupus erythematosus (SLE) patient developing steroid refractory and transfusion dependent red cell aplasia. Oral danazol 200 mg twice per day was started together with low-dose prednisolone therapy. There was no further recurrence of anemia 1 month after this combined therapy. 相似文献
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Syneretic response of aging normal human lens to pressure 总被引:2,自引:0,他引:2
PURPOSE: The study was designed to observe whether a reversible syneretic response to pressure is operative in normal human lenses and whether such a response demonstrates a uniform age dependence. METHODS: Seven sections (from the anterior outer cortex to the posterior outer cortex) of 10 human lenses were imaged at 2 atmospheres (atm) pressure and the T(1) (spin-lattice) and T(2) (spin-spin) relaxation data on each section were collected. The pressure was then released and NMR relaxographic data were collected under 1 atm. RESULTS: Both T(1) and T(2) relaxation times were at their minimum in the nuclear region and at their maximum at the two outer cortexes. With increasing pressure, T(2) relaxation times decreased. The pressure-dependent change in T(2) relaxation times decreased with age. Changes in T(1) relaxation times showed no consistent pressure or age dependence. The population index of T(2) relaxation, M(2), had a maximum in the nucleus and a minimum in the two cortexes. The population index of T(1) relaxation, M(1,) was minimal in the nucleus and maximal at the two cortexes. M(2) increased with increasing pressure, whereas M(1) did not show consistent pressure dependence. The percentage of change in M(2) (DeltaM(2)) showed a statistically significant increase with increasing age, whereas the %DeltaM(1) showed no significant age-dependent trend. CONCLUSIONS: The positional dependence of relaxation times and the population indexes indicated that spin-spin relaxation represents the behavior of the bound water and the spin-lattice relaxation that of total water. As pressure increases, the strength of hydrogen bonding as well as the amount of bound water increases. The pressure-induced change in the total water is minimal. Thus, the free water-to-bound water ratio decreases with increasing pressure, demonstrating a significant syneretic response. The extent of reversible syneretic response decreases with age and is actually reversed in older lenses. The implication is that the ability of the human lens to respond reversibly to pressure decreases with the decrease in accommodation, and, when the ability is lost altogether, an increase in free water, a possible source of cataract formation, may ensue. 相似文献
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PURPOSE: Reversible syneretic response to pressure in bovine and rhesus monkey lenses has been demonstrated previously by invasive techniques, such as differential scanning calorimetry and thermogravimetric analysis. This study is designed to investigate whether such a response could be observed by non-invasive techniques, namely by relaxographic imaging studies, in situ, in the intact, albeit excised lens. METHODS: Excised bovine lenses were incubated in media at 37 degrees C in specialized pressure chambers for 24 hrs. Three pressures, 2, 1 and 0.03 atm, were employed. The pressure chambers were placed in the cavity of an NMR magnet. Seven sections of the lens, under 2 atm pressure, from anterior outer cortex to posterior outer cortex were imaged and the T(1) (spin-lattice) and T(2 ) (spin-spin) relaxation data on each section were collected. The pressure was then released and NMR data were collected under 1 atm. Similar arrangement was followed on lenses under initial 0.03 atm pressure. T(1) and T(2) relaxations were analyzed by fitting pixel intensity to one and two term exponential expressions. RESULTS: Analysis of the time dependence of the T(2) relaxation time indicated that the response to a change in pressure is complete within 2 hours. Both T(1) and T(2) relaxation times showed minimal values in the nuclear region and maxima at the two outer cortexes. With increasing pressure both relaxation times decrease. The effect of pressure on both relaxation times was smaller in the nucleus and more enhanced at the outer cortexes. The pre-exponential terms of the fittings of both T(1) and T( 2) relaxations indicate the amount of protons participating in the relaxation. Thus they serve as a population index. The T(2) population index had a maximum in the nucleus and minima in the two cortexes. The population index of T(1) relaxation exhibited minimal value in the nucleus and maxima at the two cortexes. The pre-exponential term of T(2) relaxation increased with increasing pressure. The pre-exponential term of T(1) relaxation did not show consistent pressure dependence. CONCLUSIONS: The positional dependence of T(2) relaxation times as well as that of its population index indicated that it represents the behavior of the bound water in the lens. The positional dependence of T(1) population index suggests that this relaxation represents the total water that has a minimal value in the nucleus. Both the relaxation times as well as the population indices indicated that as pressure increases the strength of hydrogen bonding as well as the amount of bound water increases. This also means that the free water/bound water ratio decreases with increasing pressure. Thus NMR imaging and relaxation studies confirm significant syneretic response to applied hydrostatic pressure in bovine lenses. 相似文献
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Jin X Xia L Wang LS 《上海交通大学学报(医学版)》2007,27(11):1316-1316
Although cardiac hypertrophy in hypertension has been well recognized, the molecular mechanisms for the development of hypertrophy are still largely unknown. In this study, the protein expression profiles of left ventricular myocardia in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats at different ages were analyzed using 2-DE in combination with MALDI-TOF/TOF MS/MS. The results showed that 20 proteins were modulated in the hypertrophic myocardium. Out of these modulated proteins, 13 proteins presented significant changes in SHR at an early stage prior to the development of sustained hypertension, while the changes of the other 7 protein expres- sions occurred only at a late stage in SHR when the blood pressure was significantly elevated, and were largely reversible by treatment with rennin-angiotensin-aldosterone system inhibitors losartan or enalapril. These data demonstrate that the changes in energy metabolism in the hypertrophied heart favor an increase in glycolysis and a decrease in oxidation of fatty acid and glucose, which occur at an early stage in SHR without hypertension. Our results also provide evidence to support the hypothesis that oxidative stress plays an important role in the development of hypertensive cardiac hypertrophy. 相似文献
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Open-ended interviews with 107 patients documented specific patient expectations of radiologic procedures during which there was no direct radiologist-patient interaction. Patient expectations could be classified into those related to the facility and those related to interactions with radiology staff. Among facility-related expectations, waiting time far outweighed all other concerns. Interpersonal skills were the predominant expectation of radiology staff. The role of the radiologist in fulfilling patient expectations was less clear. Only 10% of unprompted patients cited the radiologist as a factor in their expectations. When patients were specifically prompted to discuss the radiologist's role, communication skills, accuracy of interpretation, and interpersonal skills were the predominant concerns. 相似文献
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Rosebrough SF; Grossman ZD; McAfee JG; Kudryk BJ; Subramanian G; Ritter- Hrncirik CA; Witanowski LS; Tillapaugh-Fay G; Urrutia E 《Radiology》1987,162(2):575-577
Radioimmunoimaging of fresh canine venous thrombi with a murine monoclonal antibody specific for human and dog fibrin has been reported. Successful imaging of canine deep venous thrombi 1, 3, and 5 days old at the time of antibody injection is reported. Images were positive in all dogs, and the uptake of fibrin-specific antibody was equivalent to that of fresh thrombi. 相似文献