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991.
The composition of 19 garlic natural health products (NHPs) and fresh garlic extracts were determined, as was their antibacterial activity. The 19 NHPs and 5 fresh garlic extract standards were analysed for their principal active constituents. They were also extracted for 5, 10 or 15 min in water to fresh garlic equivalents of 200 mg/mL. The extract's minimum inhibitory concentrations (MICs) and minimum bactericidal concentrations (MBCs) against three indicator microorganisms (Neisseria gonorrhoeae, Staphylococcus aureus and Enterococcus faecalis) were determined by the broth microdilution method. While 47% of the aqueous garlic NHP extracts exhibited activity against N. gonorrhoeae, only 16% of the aqueous extracts inhibited S. aureus or E. faecalis at all three timepoints. Generally, products with high antimicrobial activity contained higher levels of garlic constituents with comparable activity to fresh garlic extracts, while products with marginal antibacterial activity often contained lower concentrations of constituents than their product labels indicated. Different extraction times affected antibacterial activity only against N. gonorrhoeae and tended to be correlated with levels of allicin. Thus, many extracts showed discrepancies in both composition, allicin:alliin ratio and antimicrobial activity, raising concerns as to standards of preparation and quality control for these products.  相似文献   
992.
Compressed mini-tablets systems are presented as a biphasic delivery system designed for zero-order sustained drug release. The outer layer that fills the void spaces between the mini-tablets was formulated to release the drug in a very short time (fast release), while the mini-tablets provided a prolonged release. Different composition (HPMC or EC) and number (10 or 21) of mini-tablets were used to obtain different drug release rates. The in vitro performance of these systems showed the desired biphasic behaviour: the drug contained in the fast releasing phase (powder enrobing the mini-tablets) dissolved within the first 2 min, whereas the drug contained in the mini-tablets was released at different rates, depending up on formulation. Based on the release kinetic parameters calculated, it can be concluded that mini-tablets containing HPMC were particularly suitable approaching to zero-order (constant) release over 8h time periods.  相似文献   
993.
The aim of the present study was to investigate the effects of myricitrin, a flavonoid with anti-inflammatory and antinociceptive action, upon persistent neuropathic and inflammatory pain. The neuropathic pain was caused by a partial ligation (2/3) of the sciatic nerve and the inflammatory pain was induced by an intraplantar (i.pl.) injection of 20 microL of complete Freund's adjuvant (CFA) in adult Swiss mice (25-35 g). Seven days after sciatic nerve constriction and 24 h after CFA i.pl. injection, mouse pain threshold was evaluated through tactile allodynia, using Von Frey Hair (VFH) filaments. Further analyses performed in CFA-injected mice were paw edema measurement, leukocytes infiltration, morphological changes and myeloperoxidase (MPO) enzyme activity. The intraperitoneal (i.p.) treatment with myricitrin (30 mg/kg) significantly decreased the paw withdrawal response in persistent neuropathic and inflammatory pain and decreased mouse paw edema. CFA injection increased 4-fold MPO activity and 27-fold the number of neutrophils in the mouse paw after 24 h. Myricitrin strongly reduced MPO activity, returning to basal levels; however, it did not reduce neutrophils migration. In addition, myricitrin treatment decreased morphological alterations to the epidermis and dermis papilar of mouse paw. Together these results indicate that myricitrin produces pronounced anti-allodynic and anti-edematogenic effects in two models of chronic pain in mice. Considering that few drugs are currently available for the treatment of chronic pain, the present results indicate that myricitrin might be potentially interesting in the development of new clinically relevant drugs for the management of this disorder.  相似文献   
994.
In this study we performed phenotypic assays to assess involvement of the cancer chemotherapeutic agent bleomycin (BLM) in replication inhibition of mutant HIV-1 viral strains. Three clinically relevant mutant HIV variants, including one containing the Q151M mutation conferring multinucleoside resistance, were equally as sensitive to BLM as the wild-type HXB2 strain. Long-term incubation of BLM with a wild-type HIV(Ba-L) strain did not alter the sensitivity of the strain to BLM (IC(50) of BLM 0.64 microM at the beginning of incubation to 0.58 microM). At the same point in time, resistance to lamivudine (3TC) and zidovudine (AZT) was noted. Interestingly, the BLM-treated virus showed hypersensitivity to both AZT and 3TC. Our results suggest a contribution of BLM in viral load reduction in patients receiving both anticancer and antiviral agents and harbouring both wild-type and resistant HIV strains.  相似文献   
995.
Staphylococcus aureus is a gram-positive bacterium that produces several enterotoxins, which are responsible for most part of pathological conditions associated to staphylococcal infections, including lung inflammation. This study aimed to investigate the underlying inflammatory mechanisms involved in leukocyte recruitment in rats exposed to staphylococcal enterotoxin B (SEB). Rats were anesthetized with pentobarbital sodium and intratracheally injected with either SEB or sterile phosphate-buffered saline (PBS, 0.4 ml). Airways exposition to SEB (7.5-250 ng/trachea) caused a dose- and time-dependent neutrophil accumulation in BAL fluid, the maximal effects of which were observed at 4 h post-SEB exposure (250 ng/trachea). Eosinophils were virtually absent in BAL fluid, whereas mononuclear cell counts increased only at 24 h post-SEB. Significant elevations of granulocytes in bone marrow (mature and immature forms) and peripheral blood have also been detected. In BAL fluid, marked elevations in the levels of lipid mediators (LTB(4) and PGE(2)) and cytokines (TNF-alpha, IL-6 and IL-10) were observed after SEB instillation. The SEB-induced neutrophil accumulation in BAL fluid was reduced by pretreatment with dexamethasone (0.5 mg/kg), the COX-2 inhibitor celecoxib (3 mg/kg), the selective iNOS inhibitor compound 1400 W (5 mg/kg) and the lipoxygenase inhibitor AA-861 (200 microg/kg). In separate experiments carried out with rat isolated peripheral neutrophils, SEB failed to induce neutrophil adhesion to serum-coated plates and chemotaxis. In conclusion, rat airways exposition to SEB causes a neutrophil-dependent lung inflammation at 4 h as result of the release of proinflammatory (NO, PGE(2), LTB(4), TNF-alpha, IL-6) and anti-inflammatory mediators (IL-10).  相似文献   
996.
Recent anecdotal evidence suggests that it is becoming increasingly popular among ecstasy users to attempt to negate certain side-effects or enhance the drug experience through the concomitant use of pharmaceutical drugs or supplements. This study was designed to explore the practice of deliberately using pharmaceuticals for any reason in association with ecstasy and related drug (ERD) use. A cross sectional survey was conducted with 216 adults who had used ecstasy at least once in the previous 6 months. Generally, this sample was young, well educated, and likely to be in some form of paid employment. Males were slightly overrepresented within the sample. About one quarter of the sample had deliberately taken a pharmaceutical substance for its putative effects on the euphoric effects of, or recovery from, ecstasy use. Those who reported using pharmaceuticals were significantly more likely to be male, had more 'apparent' years of use, and were more likely to have injected ERDs. As a result, there appears to be a need for harm reduction information for ecstasy users regarding the risks associated with the mixture of ERDs with pharmaceuticals and supplements. Particular attention should be paid to informing users of the potentially fatal serotonin syndrome that is likely to arise from combining serotonin-enhancing substances, such as ecstasy or SSRI and MAOI groups of antidepressants.  相似文献   
997.
STUDY OBJECTIVES: To determine the risk factors for venous thromboembolism (VTE) and the rates of prophylactic measures used in acutely ill medical patients. DESIGN: Prospective observational study. SETTING: Academic tertiary care medical center. PATIENTS: One hundred seventy-nine patients admitted to three general medical units over 30 consecutive days and hospitalized for at least 3 days. MEASUREMENTS AND MAIN RESULTS: On concurrent review of the patients' medical records, 138 (77.1%) of 179 patients received one or more forms of VTE prophylaxis during their hospital stay. Of 41 (22.9%) patients receiving no VTE prophylaxis, 22 (53.7%) had and 19 (46.3%, or 10.6% of the total population) did not have a documented contraindication to anticoagulation. One hundred ten patients (61.5%) had three or more documented VTE risk factors for VTE. The most common prophylaxis was unfractionated heparin 5000 U injected subcutaneously twice/day. Therapeutic anticoagulation was given to 51 patients (28.5%) at some time during their hospitalization for indications other than VTE treatment. Two developed symptomatic VTE (1.1%) while hospitalized. Four patients (2.2%) receiving anticoagulants had adverse outcomes. One patient had minor bleeding, and one developed heparin-induced thrombocytopenia without thrombosis. CONCLUSION: Rates of VTE prophylaxis were higher than previously reported rates, although no formalized guidelines, standardized order sets, alerting programs, training, or risk-stratification tools were used during the study period. Rates of adverse events were low.  相似文献   
998.
Despite the increasing use of lamotrigine (LTG) in bipolar disorder, little is known about its impact on cognition in bipolar patients. Therefore, we have evaluated 33 bipolar I and II patients on cognitive measures (verbal memory, attention, executive functions) while receiving either LTG (n = 15) or another anticonvulsant (carbamazepine or valproate; n = 18). Patients receiving LTG were generally diagnosed as having bipolar II disorder, had experienced more depressive episodes but a lesser number of hospitalizations, and had better performance than the patients receiving carbamazepine or valproate on the verbal fluency task. A moderate effect size also suggests that both groups may differ on the immediate verbal memory test (California Verbal Learning Test). These preliminary results suggest a safer neurocognitive profile of LTG on bipolar patients, as compared with other anticonvulsants.  相似文献   
999.

Ethnopharmacological relevance

Petiveria alliacea L. (tipi) a shrub from Phytolaccaceae family is popularly used in folk medicine for treating a wide variety of disorders in South and Central America.

Aim of the study

To investigate the neuropharmacological properties on experimental animals.

Materials and methods

The acetate (FA), hexanic (FH), hydroalcoholic (FHA) and precipitated hydroalcoholic (FHAppt) fractions from the root of tipi were studied to investigate its pharmacological properties in the classical behavioral models (open-field, elevated plus maze-EPM, rotarod, barbiturate-induced sleeping time, forced swimming and pentylenetetrazole (PTZ)-induced convulsions tests) using mice. These fractions were administered intraperitoneally and orally to female mice at single doses of 100 and 200 mg/kg.

Results

All these fractions decreased the locomotor activity, rearing and grooming in the open-field test, suggesting a possible central depressant action. No significant effect was evident on motor coordination of the animals in the rotarod test. On EPM, all the fractions of tipi presented a significant reduction on the time of permanence in the open arms, indicating an absence of anxiolytic-like effect. In addition, the fractions increased the immobility time in the forced swimming test and potentiated pentobarbital-induced sleeping time in mice, confirmed a probable sedative and central depressant effect. Furthermore, the fractions increased the latency to the first convulsion and the lethal time of the PTZ-induced convulsions test in the animals, confirmed its popular use as anticonvulsant.

Conclusion

Our results suggest that the fractions of P. alliacea L. contains biologically active substance(s) that might be acting in the CNS and have significant depressant and anticonvulsant potentials, supporting folk medicine use of this plant.  相似文献   
1000.
By empowering consumers, electronic personal health records (ePHRs, more commonly PHRs) will play a key role in the evolving electronically enabled health information environment. Consumers want to be more engaged in their own healthcare and are seeking out information online. Despite intense concerns about confidentiality and security, they have high expectations for electronic health information. The growth of patient self-management tools for remote monitoring will fuel PHR adoption, if tools and standards are developed that make clinical information understandable to and usable by consumers. The value of the PHR will lie in shared information and shared decision-making, as its components support the continuity of care. Efforts in other countries can provide guidance in helping Americans do what they do best-develop and use innovative technology to serve the American people.  相似文献   
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