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11.
The genus Mentha comprises several aromatic species, which are cultivated world‐over due to their distinct aroma and commercial value. In addition to traditional food flavoring uses, Mentha are well recognized for their folk medicinal uses, especially to treat cold, fever, and digestive and cardiovascular disorders. A number of biological activities such as antioxidant, antimicrobial, biopesticidal, antitumor, anticancer, antiviral, antiallergic, antiinflammatory, antihypertensive, and urease inhibitory activity have been ascribed to Mentha. The traditional pharmacological attributes of Mentha herbs can be linked to the occurrence of bioactive phytochemicals such as terpenoids, alcohols, rosmarinic acid, and antioxidant phenolics among others. A rich source of bioactives, different species of Mentha, can be explored as a promising candidate for the development of nutra‐pharmaceuticals. This review covers the nutritional, phytochemical, and traditional medicinal aspects and multiple biological activities of some commonly available species of Mentha so as to explore their potential applications for nutra‐pharmaceutical and cosmo‐nutraceutical industry. Detailed chemical profile and pharmaceutical attributes of various Mentha essential oils are also covered. Moreover, based on computational analysis, quantitative chemical component–antioxidant activity relationship model is reviewed to predict and correlate structure–activity relationship of potential bioactives in selected Mentha essential oils leading to discovery and developmenmt of novel natural drugs.  相似文献   
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A ciliate protozoan, Euplotes mutabilis, isolated from heavy metal laden industrial wastewater, has been shown to tolerate multiple heavy metals thus suggesting its significance in bioremediation of industrial effluents. This ciliate tolerated Zn2+ up to 33 μg/mL, Cd2+ up to 22 μg/mL and Ni2+ up to 18 μg/mL. The ciliate could uptake 85% Zn2+, 84% of Cd2+ and 87% of Ni2+ after 96 h of inoculation of growth medium containing 10 μg/mL of Zn2+ and 5 μg/mL of Cd2+ and Ni2+, with actively growing ciliates. After 6 days of incubation the ciliate removed 87% Cd2+, 92% Ni2+, and 93% Zn2+ from the wastewater. The heavy metal uptake capability of Euplotes mutabilis may be employed for metal detoxification operations.  相似文献   
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Herein, we synthesized the zinc oxide (ZnO) thin films (TFs) deposited on glass substrates via spray pyrolysis (SP) to prepare self-cleaning glass. Various process parameters were used to optimize photocatalytic performance. Substrates were coated at room temperature (RT) and 250 °C with a 1 mL or 2 mL ZnO solution while maintaining a distance from the spray gun to the substrate of 20 cm or 30 cm. Several characterization techniques, i.e., XRD, SEM, AFM, and UV–Vis were used to determine the structural, morphological, and optical characteristics of the prepared samples. The wettability of the samples was evaluated using contact angle measurements. As ZnO is hydrophilic in nature, the RT deposited samples showed a hydrophilic character, whereas the ZnO TFs deposited at 250 °C demonstrated a hydrophobic character. The XRD results showed a higher degree of crystallinity for samples deposited on heated substrates. Because of this higher crystallinity, the surface energy decreased, and the contact angle increased. Moreover, by using 2 mL solution, better surface coverage and roughness were obtained for the ZnO TFs. However, by exploiting the distance of the spray to the samples size distribution and surface coverage can be controlled, the samples deposited at 30 mL showed a uniform particle size distribution from 30–40 nm. In addition, the photoactivity of the samples was tested by the degradation of rhodamine B dye. Substrates prepared with a 2 mL solution sprayed at 20 cm showed higher dye degradation than other samples, which can play a vital role in self-cleaning. Hence, by changing the said parameters, the ZnO thin film properties on glass substrates were optimized for self-cleaning diversity.  相似文献   
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The treatment of keloid and hypertrophic scar is challenging with no universally accepted mode for permanent ablation. Conventional therapies yield unpredictable results, significant complications and require elaborate hardware.

Objective

The objective was to establish the safety and efficacy of intralesional 5-fluorouracil (5-FU) for the treatment of keloids and hypertrophic scars.

Study design

Randomized controlled trial (RCT).

Place and duration

It was conducted at the Jinnah Burn and Reconstructive Surgery Center/Allama Iqbal Medical College, Lahore, Pakistan from May 2012 to March 2013.

Subjects and methods

We included 120 patients divided in two groups. The group A patients received intralesional triamcinolone acetonide (TAC) and the group B patients received both 5-FU and TAC. 8 injections at a week interval were given and patients were evaluated at the start of treatment and then at 4th and at 8th week during the treatment and then 4 weeks after the end of treatment. Patents were assessed for mean reduction in scar height, efficacy and complications.

Results

Total of 108 patients completed the study. The mean reduction in the scar height in group B (5-FU + TAC) 1.144 + .4717 was markedly better than that of group A (TAC alone) 1.894 + 1.0751 (t = 4.781, p = .000). The efficacy (defined previously as >50% reduction in initial scar height) was superior in group B 44 (77.2%) than that of group A 25 (49.0% (X2 = 9.260, p = .002). Recurrence was seen in 39.2% (20) of patients of the group A while in only 17.5% (10) of the cases of group B (P = 0.012). Mean follow up was of 22 months.

Conclusion

5-FU + TAC is safe, easy to administer and effective treatment for problematic scars and has the lower rate of recurrence on larger follow up.  相似文献   
17.
The retinoblastoma tumor suppressor protein pRb restricts cell growth through inhibition of cell cycle progression. Increasing evidence suggests that pRb also promotes differentiation, but the mechanisms are poorly understood, and the key question remains as to how differentiation in tumor cells can be enhanced in order to diminish their aggressive potential. Previously, we identified the histone demethylase KDM5A (lysine [K]-specific demethylase 5A), which demethylates histone H3 on Lys4 (H3K4), as a pRB-interacting protein counteracting pRB''s role in promoting differentiation. Here we show that loss of Kdm5a restores differentiation through increasing mitochondrial respiration. This metabolic effect is both necessary and sufficient to induce the expression of a network of cell type-specific signaling and structural genes. Importantly, the regulatory functions of pRB in the cell cycle and differentiation are distinct because although restoring differentiation requires intact mitochondrial function, it does not necessitate cell cycle exit. Cells lacking Rb1 exhibit defective mitochondria and decreased oxygen consumption. Kdm5a is a direct repressor of metabolic regulatory genes, thus explaining the compensatory role of Kdm5a deletion in restoring mitochondrial function and differentiation. Significantly, activation of mitochondrial function by the mitochondrial biogenesis regulator Pgc-1α (peroxisome proliferator-activated receptor γ-coactivator 1α; also called PPARGC1A) a coactivator of the Kdm5a target genes, is sufficient to override the differentiation block. Overexpression of Pgc-1α, like KDM5A deletion, inhibits cell growth in RB-negative human cancer cell lines. The rescue of differentiation by loss of KDM5A or by activation of mitochondrial biogenesis reveals the switch to oxidative phosphorylation as an essential step in restoring differentiation and a less aggressive cancer phenotype.  相似文献   
18.
Introduction: Idiopathic systemic capillary leak syndrome (SCLS) is a unique disorder characterized by episodes of massive systemic leak of intravascular fluid leading to volume depletion and shock. A typical attack of SCLS consists of prodromal, leak and post-leak phases. Complications, such as compartment syndrome and pulmonary edema, usually develop during the leak and post-leak phases respectively. Judicious intravenous hydration and early use of vasopressors is the cornerstone of management in such cases.

Areas covered: The purpose of the present review is to provide an up-to-date, evidence-based review of our understanding of SCLS and its management in the light of currently available evidence.

Commentary: Idiopathic SCLS was first described in 1960 and, since then, more than 250 cases have been reported. A large number of cases have been reported over the past one decade, most likely due to improved recognition. In the acute care setting, most patients with SCLS are managed as per the Surviving Sepsis guidelines and receive aggressive volume resuscitation – which is not the optimal management strategy for such patients. There is a need to raise awareness amongst physicians and clinicians in order to improve recognition of this disorder and ensure its appropriate management.  相似文献   

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Prussian blue analogs (PBAs) are attractive cathode candidates for high energy density, including long life-cycle rechargeable batteries, due to their non-toxicity, facile synthesis techniques and low cost. Nevertheless, traditionally synthesized PBAs tend to have a flawed crystal structure with a large amount of [Fe(CN)6]4− openings and the presence of crystal water in the framework; therefore the specific capacity achieved has continuously been low with poor cycling stability. Herein, we demonstrate low-defect and sodium-enriched nickel hexacyanoferrate nanocrystals synthesized by a facile low-speed co-precipitation technique assisted by a chelating agent to overcome these problems. As a consequence, the prepared high-quality nickel hexacyanoferrate (HQ-NiHCF) exhibited a high specific capacity of 80 mA h g−1 at 15 mA g−1 (with a theoretical capacity of ∼85 mA h g−1), maintaining a notable cycling stability (78 mA h g−1 at 170 mA g−1 current density) without noticeable fading in capacity retention after 1200 cycles. This low-speed synthesis strategy for PBA-based electrode materials could be also extended to other energy storage materials to fabricate high-performance rechargeable batteries.

A low-speed synthesis strategy was designed to fabricate Prussian blue analog based electrode materials for high-performance rechargeable batteries.  相似文献   
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