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991.
Objectives We have tested the cardiovascular effects of N‐(4′‐dihydro)‐piperoylthiomorpholine (LASSBio 365) on rats using an in‐vivo and in‐vitro approach. Methods LASSBio 365 (0.025, 0.05, 0.1, 0.25, 0.5 or 1 mg/kg, randomly injected) was administered to conscious unrestrained rats and the mean arterial pressure and heart rate were measured. The effects of LASSBio 365 (3 × 10?6–3 × 10?4m ) on rat isolated aortic rings with and without endothelium were investigated. Key findings LASSBio 365 induced a dose‐dependent decrease in mean arterial pressure and heart rate (ED50 = 158 ± 53 µg/kg). The effects evoked by LASSBio 365 (0.5 mg/kg) were inhibited by pretreatment with atropine. In anaesthetized rats, electrocardiogram recordings revealed second/third degree sinoatrial and atrioventricular blockade induced by the compound, which were completely inhibited after cardiac muscarinic blockade or cervical bilateral vagotomy. In rat isolated aortic rings, LASSBio 365 (3 × 10?6–3 × 10?4m ) was capable of antagonizing the contractile effects induced by phenylephrine (1 µm ) or KCl (80 mm ) (IC50 = 107 ± 6; 92 ± 6 µm , respectively). This effect was not inhibited after removal of the vascular endothelium (IC50 = 84 ± 4; 92 ± 10 µm , respectively). LASSBio 365 (10?6–10?4m ) antagonized CaCl2‐induced contractions in a concentration‐dependent manner. Furthermore, LASSBio 365 (98 µm ) inhibited contractions produced by noradrenaline (1 µm ), but not those induced by caffeine (20 mm ). Conclusions These results suggested that LASSBio 365 produced negative chronotropism and reduced peripheral resistance that were probably due to the stimulation of cardiac muscarinic pathways. Peripheral vasodilation was probably linked to voltage‐dependent Ca2+‐channel blockade and/or specific inhibition of Ca2+ release from noradrenaline‐sensitive intracellular stores.  相似文献   
992.
High voltage electrical stimulation has been recommended as a means of accelerating the wound healing process. The effects of high voltage electrical stimulation were evaluated in the treatment of three volunteers with chronic ulcers of the lower limbs. After fifteen weeks of treatment, a reduction was found in the area of all the ulcers, suggesting that high voltage electric stimulation is an effective therapeutic option for chronic ulcers.  相似文献   
993.
994.
Clean rooms are largely employed in pharmaceutical companies whose purpose is to produce sterile drugs and devices. We employed Gram staining and gas chromatography of fatty acid methyl esters extracted from whole cells of environmental isolates to characterize and identify bacteria isolated in each of 50 different clean rooms designed for the manufacturing of sterile medicinal products and to provide a fatty acid profile of the most common species of isolated bacteria. Statistical analysis allowed us to corroborate previous studies and confirm that Gram-positive cocci are the most relevant group of microorganisms inside the studied clean rooms. The predominant species is Micrococcus luteus, isolated from Grade B zones and from personnel, followed by Staphylococcus cohnii in Grade C, Bacillus subtilis in Grade A, and S. hominis in Grade D. Fatty acid profiles of these bacteria are, to a great extent, consistent with standard libraries. We also attempted to establish a correlation between season and level of contamination, although variance analysis showed that there is no significant difference on the level of contamination throughout seasons. Therefore, we believe that this work can contribute to identifying and understanding the bacterial community of some pharmaceutical clean rooms.  相似文献   
995.
996.

Objective

The BCL2 family proteins are critical mediators of cellular apoptosis and, as such, have been implicated as determinants of cancer cell chemo-sensitivity. Recently, it has been demonstrated that the phosphorylation status of the BCL2 antagonist of cell death (BAD) protein may influence ovarian cancer (OVCA) cell sensitivity to cisplatin. Here, we sought to evaluate how kinase and phosphatase components of the BAD apoptosis pathway influence OVCA chemo-sensitivity.

Methods

Protein levels of cyclin-dependent kinase 1 (CDK1) and protein phosphatase 2C (PP2C) were measured by immunofluorescence in a series of 64 primary advanced-stage serous OVCA patient samples. In parallel, levels of cAMP-dependent protein kinase (PKA), AKT, and PP2C were quantified by Western blot analysis in paired mother/daughter platinum-sensitive/resistant OVCA cell lines (A2008/C13, A2780S/A2780CP, Chi/ChiR). BAD pathway kinase CDK1 was depleted using siRNA transfection, and the influence on BAD phosphorylation and cisplatin-induced apoptosis was evaluated.

Results

OVCA patient samples that demonstrated complete responses to primary platinum-based therapy demonstrated 4-fold higher CDK1 (p<0.0001) and 2-fold lower PP2C (p=0.14) protein levels than samples that demonstrated incomplete responses. Protein levels of PP2C were lower in the platinum-resistant versus that shown in the platinum-sensitive OVCA cell line sub-clones. Levels of PKA were higher in all platinum-resistant than in platinum-sensitive OVCA cell line sub-clones. Selective siRNA depletion of CDK1 increased sensitivity to cisplatin-induced apoptosis (p<0.002).

Conclusion

BAD pathway kinases and phosphatases, including CDK1 and PP2C, are associated with OVCA sensitivity to platinum and may represent therapeutic opportunities to enhance cytotoxic efficacy.  相似文献   
997.
OBJECTIVE: This study was designed to assess possible antidepressant effects of memantine, a selective N-methyl-D-aspartate (NMDA) receptor antagonist in humans. METHOD: In a double-blind, placebo-controlled study, 32 subjects with major depression were randomly assigned to receive memantine (5-20 mg/day) (N=16) or placebo (N=16) for 8 weeks. Primary efficacy was assessed by performance on the Montgomery-Asberg Depression Rating Scale (MADRS). RESULTS: The linear mixed models for total MADRS scores showed no treatment effect. CONCLUSIONS: In an 8-week trial, the low-to-moderate-affinity NMDA antagonist memantine in doses of 5-20 mg/day was not effective in the treatment of major depressive disorder.  相似文献   
998.
The frequency, characteristics and reversibility of bortezomib-associated peripheral neuropathy were evaluated in the phase III APEX (Assessment of Proteasome Inhibition for Extending Remissions) trial in patients with relapsed myeloma, and the impact of a dose-modification guideline on peripheral neuropathy severity and reversibility was assessed. Patients received bortezomib 1·3 mg/m2 (days 1, 4, 8, 11, eight 21-d cycles, then days 1, 8, 15, 22, three 35-d cycles); bortezomib was held, dose-reduced or discontinued depending on peripheral neuropathy severity, according to a protocol-specified dose-modification guideline. Overall, 124/331 patients (37%) had treatment-emergent peripheral neuropathy, including 30 (9%) with grade ≥3; incidence and severity were not affected by age, number/type of prior therapies, baseline glycosylated haemoglobin level, or diabetes history. Grade ≥3 incidence appeared lower versus phase II trials (13%) that did not specifically provide dose-modification guidelines. Of patients with grade ≥2 peripheral neuropathy, 58/91 (64%) experienced improvement or resolution to baseline at a median of 110 d, including 49/72 (68%) who had dose modification versus 9/19 (47%) who did not. Efficacy did not appear adversely affected by dose modification for grade ≥2 peripheral neuropathy. Bortezomib-associated peripheral neuropathy is manageable and reversible in most patients with relapsed myeloma. Dose modification using a specific guideline improves peripheral neuropathy management without adversely affecting outcome.  相似文献   
999.
Situations of stress are capable of inducing depression and oxidative stress in the brain. Previous reports have shown that angiotensin II (Ang II) induces the production of superoxide anion (O(2)(-)), and impairment of endothelial function in cerebral microvessels in vivo. Substances that reduce angiotensin functions may be important in the treatment of depression. These data suggest a role for both Ang II and O(2)(-) in depression; thus, the aim of this study was to determine the effect of forced swimming test (FST), a model of stress/depression, on the cellular expression of Ang II and O(2)(-) in the central nervous system. To induce stress/depression, rats were subjected to FST daily (30 min) for 15 days. Unstressed animals were used as controls. Motor activity was automatically analyzed daily before swimming. Cerebrum and cerebellum frozen sections were studied for O(2)(-) by a histochemical method and for Ang II producing cells by a polyclonal antibody. In the FST group, struggle time, total horizontal activity, ambulatory movements, and vertical movements, were significantly decreased when the data from the 1st and 15th day were compared. Food intake and body weight gain also decreased when unstressed and FST rats were compared at the 15th day. Increased number of cerebrum and cerebellum O(2)(-), and Ang II positive cells, were observed in FST rats. Significant correlation was found between O(2)(-) positive cells and Ang II positive cell in the cerebrum. These results suggest that stress/depression situations could be involved in the increase of Ang II and oxidative stress in the central nervous system, with possible implications in the depressive condition.  相似文献   
1000.
The authors describe the frequency and characteristics of Cotard syndrome among neurological and psychiatric inpatients at a tertiary referral center. All inpatients from the National Institute of Neurology of Mexico (March 2007-May 2009) requiring neuropsychiatric consultation were reviewed. Among 1,321 inpatient consultations, 63.7% had neurological disease and one (0.11%) had viral encephalitis and Cotard syndrome. Of inpatients, 36.2% had pure psychiatric disorders and three (0.62%) had Cotard syndrome, associated with psychotic depression, depersonalization, and penile retraction (koro syndrome). This review discusses potential mechanisms for Cotard syndrome, including the role of a perceptual-emotional dissociation in self-misattribution in the deliré des negations.  相似文献   
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