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81.
Nitric oxide (NO) acts as a vasorelaxant. We investigated the relationship between nitrite/nitrate (NOx), which are the final metabolites of NO, and hemodynamics during septic shock. We also examined tumor necrosis factor α (TNF-α), interleukin-8 (IL-8), and endotoxin. A significant negative correlation was observed between NOx levels and pulmonary capillary wedge pressure (PCWP; r = −0.6075, P = 0.0028). A significant positive correlation was noted between NOx levels and the cardiac index (CI; r = 0.5934, P = 0.0038). A significant negative correlation was found between NOx levels and the systemic vascular resistance index (SVRI; r = −0.4354, P = 0.0485). A significant positive correlation was observed between NOx levels and the stroke volume index (SVI; r = 0.5040, P = 0.0186). A significantly close positive correlation was also observed between TNF-α levels and NOx levels (r = 0.7848, P < 0.0001). These findings suggest that NOx levels are closely associated with hemodynamics during septic shock, resulting in a vascular relaxing effect. Received: July 6, 1999 / Accepted: March 24, 2000  相似文献   
82.
The effects of virol A (VA), a toxic component of Cicuta virosa (water hemlock), on the GABA-induced Cl(-) current (I(GABA)) in acutely dissociated rat hippocampal CA1 neurons were investigated using whole-cell patch-clamp techniques. VA reversibly reduced I(GABA) and the muscimol (Mus)-induced current (I(Mus)) in a concentration-dependent manner. The IC(50) values for VA against I(GABA) and I(Mus) were 9.6x10(-7) and 9.8x10(-7) M, respectively. VA shifted the EC(50) value of I(GABA) from 6.5x10(-6) to 2.1x10(-5) M, whereas it had no effect on the maximum response, thereby suggesting that VA inhibited I(GABA) in a competitive manner. VA had no apparent effect on current-voltage relationships for I(GABA), thus indicating the lack of voltage-dependency. On the other hand, application of VA (10(-6) M) did not additionally reduce the I(GABA) suppressed by >10(-5) M picrotoxin. VA but not bicuculline accelerated the decay phase of I(GABA), as was seen with picrotoxin. Moreover, pre-application of 10(-5) M VA reduced I(GABA). VA did not inhibit that induced by glycine (10(-4) M). These results indicate that VA inhibits I(GABA) by acting both on the GABA agonist site and on the Cl(-) channel of the GABA(A) receptor-channel complex. VA is a structurally novel type of compound that selectively inhibits the GABA(A) receptor-Cl(-) channel complexes in mammalian central nervous system neurons.  相似文献   
83.
84.
The effects of conjugated linoleic acid (CLA), gamma-linolenic acid (GLA), linoleic acid (LA), and their combinations, on skin composition in mice were investigated. Mice (8 weeks old) were orally administered with either LA, GLA, CLA, LA + GLA, LA + CLA, or CLA + GLA for 4 weeks. Then, the skin was analysed for triacylglycerol content, fatty acid composition and collagen content. Additionally, thicknesses of the dermis layer and subcutaneous tissue layer, and the size and number of adipocytes were measured histologically. The skin fatty acid composition was modified depending upon the fatty acid composition of supplemented oils. In each oil-alone group, skin triacylglycerol content was the highest in LA, followed by GLA and CLA treatments. Combinations with CLA had a similar triacylglycerol content compared with the CLA-alone group. No significant changes in collagen content were observed among any treatments. The effects on subcutaneous thickness were similar to the results obtained in the triacylglycerol contents, where groups supplemented with CLA alone or other fatty acids had significantly thinner subcutaneous tissue compared with the LA-alone group. However, no significant difference was detected in the thickness of the dermis layers. The number of adipocytes was highest in the LA + GLA group and tended to be reduced by CLA with or without the other fatty acids. These results suggest that CLA alone or in combination with other fatty acids strongly modifies skin composition in mice.  相似文献   
85.
The synthesis and antiviral activity of 3'-N-trifluoroacetylkanamycin A derivatives (6) having higher acyl group at the N-1 position are described. On the basis of the structure-activity relationships between antiviral activity and alkyl chain length in an acyl group at the N-1 position, analogs (6f approximately I) having higher alkylcarbonyl group exhibited antiviral activity against not only HSV-I but also influenza virus. Analogs (6q approximately v) having higher alkyloxycarbonyl group showed antiviral activity against HSV-I. In addition, kanamycin A derivatives (6n, o, y, z) possessing higher alkylcarbonyl group with a functional group, higher alkylaminocarbonyl group, and higher alkylthiocarbonyl group had antiviral activity against HSV-I. The analog (6h) showed a broad antiviral spectrum against both DNA (HSV-I, HSV-II, VZV) and RNA (influenza) viruses.  相似文献   
86.
87.
Somatic hallucinations are subjective experience of false, strange sensations of things occurring in or to the body. They can be seen in psychotic disorders, but have not been well described as an ictal psychosis in patients with nonconvulsive status epilepticus (NCSE) of frontal origin. We reported a 69-year-old woman who had NCSE of frontal origin manifesting prolonged somatic hallucinations mimicking a psychiatric disorder and initially treated as such. Ictal EEG revealed the frontal focus and ictal single-photon emission computed tomography (SPECT) showed the activation, not only in the frontal area but also in the parietal area as the projected regions, both of which might be associated with the development of her symptoms. She also had two generalized tonic-chronic seizures out of psychosis. Her psychosis and ictal rhythmic discharges on EEG ceased with valproate and she has since remained free from the symptoms. The current case suggests that long-lasting somatic hallucinations could be an ictal psychosis in frontal NCSE and thus an EEG study is needed for an early diagnosis and treatment.  相似文献   
88.
Purpose. Total gastrectomy (GX) leads to osteopenia. We examined the effects of bisphosphonate incadronate (INC), a potent inhibitor of bone resorption, on bone characteristics in rats that underwent total GX. Experimental design. Male Wistar rats were divided into four groups: (1) sham-operation (n = 10); (2) total GX control (n = 6); (3) total GX with 0.3 mg kg−1 day−1 oral administration of INC (n = 7); and (4) total GX with 3.0 mg kg−1 day−1 oral administration of INC (n = 7). Results. Total GX significantly impaired bone mineral density; these effects were prevented by treatment with INC. Similarly, in GX control rats, morphometrical changes of femoral metaphysis stained with Villanueva's and Villanueva-Goldner's: bone volume, tissue volume, mineral apposition rate, labeled/bone surface, bone formation rate, osteoid volume, mineralization lag time as well as serum osteocalcin, and urinary deoxypyridinoline demonstrated simultaneous existence of both osteomalacia and osteopenia; these impairments were also prevented by INC. However, GX-induced decrease in serum levels of calcium as well as 25-hydroxyvitamin D/24,25-dihydroxyvitamin D and the increase in 1,25-dihydroxyvitamin D were not prevented by administration of INC. Conclusions. These results enhance the understanding of the unique pathophysiology of both osteomalacia and osteoporosis induced by total GX and suggest the possibility of using INC as preventive therapy for osteopenia in GX-treated patients.  相似文献   
89.
Interferon-beta (IFN-beta) has been used as an antitumor drug against human glioma, melanoma and medulloblastoma since the 1980s. Recently, we developed a new gene therapy using the IFN-beta gene against malignant gliomas and then began clinical trials in 2000. Since stimulation of immune system was one mechanism of antitumor effect induced by IFN-beta gene therapy, we hypothesized that combination of IFN-beta gene therapy with immunotherapy might increase its effectiveness. In the present study, we tested whether combination therapy with IFN-beta gene therapy and immunotherapy using tumor cell lysate-pulsed dendritic cells (DCs) would increase the efficacy of IFN-beta gene therapy. In an experimental mouse intracranial glioma (GL261), which cannot be cured by either IFN-beta gene therapy or DC immunotherapy alone, IFN-beta gene therapy following DC immunotherapy resulted in a significant prolongation in survival of the mice. Moreover, when this combination was performed twice, 50% of treated mice survived longer than 100 days. Considering these results, this combination therapy may be one promising candidate for glioma therapy in the near future.  相似文献   
90.
BACKGROUND: We retrospectively studied the relationship between linear hyperintensity objects (LHOs) on T(2)-weighted magnetic resonance images (MRI) in the cerebral white matter and the occurrence of hypertensive intracerebral hemorrhage (HIH). METHODS: Forty-nine hypertensive patients with a fixed imaging condition MRI were classified into three groups: HIH (n = 17), ischemic stroke due to hypertensive vasculopathy (n = 19), and hypertension only (n = 13). After assessing clinical and radiological background information among these groups and the reliability of LHO measurements, polynomial logistic regression analysis was used to identify the factors relating to HIH. RESULTS: HIH had a significantly higher LHO number (p = 0.002) and larger diameter (p = 0.007). The LHO number showed an excellent interrater (kappa = 0.91, 95% CI = 0.87-0.94, SEM = 6.2%) and intrarater reliability (kappa = 0.95, 95% CI= 0.92-0.97, SEM = 4.8%), and was the most significant independent indicator of HIH (OR = 1.29, 95% CI = 1.05-1.60, p = 0.017). The number of microbleeds was an additional indicator (OR = 3.73, 95% CI = 1.10-12.65, p = 0.034). CONCLUSIONS: LHOs are closely linked to HIH. A prospective, longitudinal study is needed to clarify whether LHOs can predict HIH.  相似文献   
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