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1.
Direct measurement of intra-arterial blood pressure (BP) for 24-h provides approximately 100,000 values that vary enormously, but each (BPi) can be expressed by the equation BPi = BP0 + DeltaBPi (BP0, base BP; DeltaBPi, BP increment, i=1, 2, ..., 100 x 10(3)). About 20% of outpatients with hypertension exhibit white-coat hypertension (WCH). In such patients, DeltaBPc (i = c; c, time at the clinic) is surmised to be large. A method for explaining the physiological factors in DeltaBPc and the estimation of base BP in the outpatient clinic is important. This study addresses this issue. A total of 293 subjects were divided into four groups: 1) WCH group, 45 individuals (office BP > or = 140/90 mmHg and 24-h indirect BP < 125/80 mmHg); 2) normotensive (NT) group, 84 controls matched for age and sex; 3) WHO-I group, 95 hypertensive patients with WHO stage I (office BP > or = 140/90 mmHg and 24-h BP > or = 125/80 mmHg); and 4) WHO-II group, 69 hypertensive patients with WHO stage II. Their BPc and heart rate (HR; HRc, clinic HR) values were measured by a BP-ECG monitoring device in the outpatient clinic. Power-spectral analysis was used to obtain the ratio between the low-frequency component (LF) and high-frequency component (HF) of ECG-RR variability (LF/HF = LH). Twenty-four-hour indirect BP (and BP0) and base HR (HR0) were measured by a portable device (TM2425) at 30-min intervals. Then, DeltaBPc (= BPc - BP0) was estimated by performing linear multivariate analysis applying the model equation DeltaBPc = (BPc -alphaLH)(1-betaHR0/HRc) + epsilon to the above variables (alpha and beta, constant values; epsilon, error). This model equation made it possible to estimate BP0 (and DeltaBPc) with a high coefficient of correlation (r > or = 0.85, mean of error less than 0.82 +/- 5.9 mmHg). The predictive accuracy for discrimination between WCH and sustained hypertension (WHO-I and WHO-II groups) by this equation was 88%. The new DeltaBP-estimation device (BP-ECG monitor) enabled us to infer BP0 and is therefore useful in estimating WCH in the outpatient clinic.  相似文献   
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The TT virus (TTV) load was estimated in sera obtained from 237 patients with hepatitis C virus (HCV)-related chronic liver disease including 42 patients with hepatocellular carcinoma (HCC), by real-time detection PCR using primers and a probe derived from the well-conserved untranslated region of the TTV genome, which can detect all known TTV genotypes. Of the 237 patients studied, 18 (8%) were negative for TTV DNA, 87 (37%) had low TTV viremia (1.3 x 10(2)-9.9 x 10(3) copies/ml), and 132 (56%) had high TTV viremia (1.0 x 10(4)-2.1 x 10(6) copies/ml). Various features were compared between the patients with high TTV load (n = 132) and those with no TTV viremia or low viral load (n = 105). High TTV viremia (> or =10(4) copies/ml) was significantly associated with higher age (P < 0.05), past history of blood transfusion (P < 0.001), complication of cirrhosis (P < 0.05) or HCC (P < 0.0005), lower HCV RNA titer (P < 0.05), and lower platelet count (P < 0.01). On multivariate logistic regression analysis, high TTV viral load was a significant risk factor for HCC (P < 0.05), independent from known risk factors such as complication of liver cirrhosis (P < 0.0001) and high age (> or =65 years, P < 0.05), among all 237 patients. Furthermore, high TTV viral load was an independent risk factor for HCC among the 90 cirrhotic patients (P < 0.05). These results suggest that a high TTV viral load is associated independently with the complication of HCC and may have prognostic significance in patients with HCV-related chronic liver disease, although whether high TTV viremia mediates the progression of HCV-related chronic liver disease remains to be defined.  相似文献   
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Watanabe M  Tokita Y  Kato M  Fukuda Y 《Neuroscience》2003,116(3):733-742
Some retinal ganglion cells in adult cats survive axotomy for two months and regenerate their axons when a peripheral nerve is transplanted to the transected optic nerve. However, regenerated retinal ganglion cells were fewer than 4% of the total retinal ganglion cell population in the intact retina. The present study examined the effects of intravitreal injections of neurotrophic factors (brain-derived neurotrophic factor, ciliary neurotrophic factor, basic fibroblast growth factor, glial cell-derived neurotrophic factor, neurotrophin 4), first on the survival of axotomized cat retinal ganglion cells within 2 weeks, and then on axonal regeneration of the retinal ganglion cells for 2 months after peripheral nerve transplantation. We tested first enhancement of the survival by one of the factors, and then one or two of them supplemented with forskolin, which increases intracellular cAMP. Single injections of 0.5 microg or 1 microg brain-derived neurotrophic factor, 1 microg ciliary neurotrophic factor, or 1 microg glial cell-derived neurotrophic factor significantly increased total numbers of surviving retinal ganglion cells; 1.6-1.8 times those in control retinas. Identification of retinal ganglion cell types with Lucifer Yellow injections revealed that the increase of surviving beta cells was most conspicuous: 2.5-fold (brain-derived neurotrophic factor) to 3.6-fold (ciliary neurotrophic factor). A combined injection of 1 microg brain-derived neurotrophic factor, 1 microg ciliary neurotrophic factor, and 0.1 mg forskolin resulted in a 4.7-fold increase of surviving beta cells, i.e. 50% survival on day 14. On the axonal regeneration by peripheral nerve transplantation, a combined injection of brain-derived neurotrophic factor, ciliary neurotrophic factor, and forskolin resulted in a 3.4-fold increase of beta cells with regenerated axons. The increase of regenerated beta cells was mainly due to the enhancing effect of neurotrophic factors on their survival, and possibly to a change of retinal ganglion cell properties by cAMP to facilitate their axonal regeneration.  相似文献   
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The effects of a synthetic serine protease inhibitor, FOY-305, on the proliferation of normal and transformed mouse fibroblasts were investigated in vitro by MTT colorimetric assay. FOY-305 inhibited the growth of normal NIH3T3 cells and their src- and erbB2-transformed cells with a half maximum inhibitory concentration (IC50) of 1-1.2 mg/ml whereas it suppressed the growth of ras-transformed cells more effectively (IC50 was 0.5-0.6 mg/ml). Flow cytometric analysis using synchronized NIH3T3 cells has shown that the growth-inhibitory activity of FOY-305 was due to the suppression of G(1)/S transition. The synergistic effects between FOY-305 and traditional anticancer drugs were also investigated by the MTT assay and the results showed that FOY-305 significantly enhanced the antiproliferative activities of 5-fluorouracil (5-FU), 1-hexylcarbamoyl-5-fluorouracil (HCFU), 7-ethyl-1-hydroxy-7-ethyl-10-[4-(1-piperidino)-1-piperidino] camptothecin (SN-38), pirarubicin (THP) and 1-(4-amino-2-methyl-5-pyrimidinyl)-methyl-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU).  相似文献   
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K Tokita  K Kanno  K Ikeda 《Atherosclerosis》1977,28(2):111-119
Elastin preparations were isolated from human thoracic aorta, from atherosclerotic and from grossly normal regions. A relatively mild procedure was used to avoid hot alkaline extraction and autoclaving. The elastase digest of the aortic elastin was chromatographed on a Sephadex G-100 column and separated into two fractions: A (larger molecular weight) and B (smaller molecular weight). The ratio of fraction A to total aortic elastin increased with age and the development of the atherosclerosis. Amino acid and sugar analyses showed that fraction A consistently contained more polar amino acids, hexose, hexosamine and L-fucose, and less sialic acid, in comparison with fraction B. Part of the elastin preparation was incubated with human low-density lipoprotein; a considerable amount of lipid, especially cholesterol, was transferred from the lipoprotein to the elastin. Estimation of protein and cholesterol in fractions A and B of the elastase hydrolyzate of incubated elastin showed that most of the cholesterol taken up by elastin had been in fraction A. The increased proportion of fraction A in aortic elastin derived from plaque areas appeared responsible for the marked lipid-binding capacity of plaque elastin.  相似文献   
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The microlamellar and smectic liquid crystal (LC) structures of a block copolymer of a main‐chain LC polyester connected at both ends with poly(ethyl methacrylate) are investigated by fiber X‐ray scattering. In the as‐spun fiber, the lamellae are parallel to the fiber axis, while the smectic layers are perpendicular to it. Annealing the as‐spun fiber at a temperature higher than the isotropization temperature (Ti) of the LC segment preserves the lamellae, but the LC structure disappears. Further annealing the fiber at T < Ti improves the lamellar stacking coherence and aligns the smectic layers parallel to the lamellae. In contrast, annealing the as‐spun fiber at T < Ti conserves the smectic layers and arranges the lamellae in parallel to the smectic layers. Thus, the liquid crystallinity affects the lamellar ordering and orientation.

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