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121.
Summary The vasopressor activity of human amniotic fluid was assessed in 46 primigravidas during the third trimester of pregnancy. The subjects included 20 normal and 26 cases of pregnancy toxaemia. For identification of the vasoptessor activity of the amniotic fluid, blood pressure measurements were made in the intact rat, and the smooth muscle contraction of the rat ascending colon preparation was determinedin vitro. The samples of amniotic fluid showing vasoptessor activity were lyophilized and subjected to gel filtration using Sephadex G-100. The various fractions thus obtained were monitored at 280 nm and the pressor activity was re-estimated. It was observed that most of the pressor activity of the amniotic fluid of the toxaemic patients was capable of causing contraction of the rat colon as well as a significant rise in the systolic blood pressure of the intact rat. Furthermore, this activity was found to be heat-labile and was completely blocked by cinnarizine. Fractionation of the amniotic fluid showing vasopressor activity by gel filtration further substantiated the findings reported above. On the basis of these results it was concluded that the pressor activity of the amniotic fluid was due to the presence of an angiotensin II-like substance. Its concentration was found to be higher in the toxaemic group than in normotensive subjects.  相似文献   
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Ayurveda is the oldest system of Medicine in the world, its antiquity going back to the Vedas. It adapts a unique holistic approach to the entire science of life, health and cure. The areas of special consideration in Ayurveda are geriatrics, rejuvenation, nutrition, immunology, genetics and higher consciousness. The Ayurvedic texts describe a set of rejuvenative measures to impart biological sustenance to the bodily tissues. These remedies are called Rasayana which are claimed to act as micronutrients. Some of these Rasayanas are organ and tissue specific. Those specific to brain tissue are called Medhya Rasayana. Such Rasayanas retard brain aging and help in regeneration of neural tissues besides producing antistress, adaptogenic and memory enhancing effect. In addition to the long tradition of textual and experience-based evidence for their efficacy, certain recent studies conducted on these traditional remedies on scientific parameters have shown promising results which have been reviewed in this paper for providing lead for further studies. The popular Medhya Rasayanas are Ashwagandha (Withania somnifera Dunal), Brahmi (Bacopa monnieri Linn), Mandukaparni (Centella asiatica Linn) and Sankhapuspi (Convolvulus pluricaulis Chois).  相似文献   
125.

Background

Elevated plasma lactate has been shown to correlate with mortality in patients with septic shock. Heat stress prior to sepsis has resulted in reduction in acute lung injury and mortality. We investigated whether heat stress resulted in decreased plasma lactate concentration and protected the lung by decreasing the inflammatory response to sepsis.

Results

Plasma lactate concentration was elevated in septic rats without prior heat stress. Lactic acid levels were significantly lower in heat-treated septic rats (P < 0.05) and were not significantly different when compared with control rats. Septic rats with or without heat pretreatment had significantly higher myeloperoxidase activity in the lung than did control groups. Heat pretreatment did not prevent neutrophil infiltration or inflammatory mediator production in the lung.

Conclusion

Prior heat stress ameliorates lactic acidemia in rat sepsis. Heat stress did not attenuate the pulmonary inflammatory process. The mechanism of heat-induced protection from lactic acidemia in sepsis needs to be further explored.  相似文献   
126.

Context

High-grade T1 (formerly T1G3) bladder cancer (BCa) has a high propensity to recur and progress. As a result, decisions pertaining to its treatment are difficult. Treatment with bacillus Calmette-Guérin (BCG) risks progression and metastases but may preserve the bladder. Cystectomy may offer the best opportunity for cure but is associated with morbidity and a risk of mortality, and it may constitute potential overtreatment for many cases of T1G3 tumours. For purposes of this review, we continue to refer to high-grade T1 lesions as “T1G3.”

Objective

To review the current literature on the management of T1G3 BCa and to provide recommendations for its treatment.

Evidence acquisition

A National Center for Biotechnology Information (NCBI) PubMed search for relevant articles published between 1996 and 9 January 2009 was performed using the Medical Subject Headings “T1G3” or “T1” and “Bladder cancer.” Articles relevant to the treatment of T1G3 BCa were retained.

Evidence synthesis

The diagnosis of T1G3 disease is difficult because pathologic staging is often unreliable and because of the risk of significant understaging at initial transurethral resection (TUR) of bladder tumour. A secondary restaging TUR is recommended for all cases of T1G3. A single dose of immediate post-TUR chemotherapy is recommended. For a bladder-sparing approach, intravesical BCG should be given as induction with maintenance dosing. Immediate or early radical cystectomy (RC) should be offered to all patients with recurrent or multifocal T1G3 disease, those who are at high risk of progression, and those failing BCG treatment.

Conclusions

Both bladder preservation and RC are appropriate options for T1G3 BCa. Risk stratification of patients based on pathologic features at initial TUR or at recurrence can select those most appropriate for bladder preservation compared to those for whom cystectomy should be strongly considered.  相似文献   
127.
Formononetin (FMN) is a methoxylated isoflavone which is the major constituent in red clover and in commercially available extracts of this plant. In this study, we investigated the parallel artificial membrane permeability assay (PAMPA) permeability, protein binding, blood uptake characteristics, pharmacokinetics and metabolism of FMN. The permeability study samples were analyzed by HPLC-PDA method; whereas the pharmacokinetic study, protein binding and whole blood partitioning samples were analyzed by LC-MS/MS method. The PAMPA permeability of FMN was found to be high at pH 4.0 and 7.0. Plasma protein binding of FMN was found to be 93.61 ± 0.44% and 96.14 ± 0.15% at the tested concentration of 50 and 150 ng/mL, respectively. FMN reached equilibrium fast between red blood cells (RBCs) and plasma, and the partition coefficients between RBCs and plasma (KRBC/PL) were independent of the initial rat blood concentrations of FMN. The bioavailability of unchanged/free FMN was found to be poor, i.e. approximately 3%. FMN was found to have a high clearance (5.13 L/h/kg) and a large apparent volume of distribution (14.16 L/kg). Circulating conjugates (glucuronides/sulfates) of FMN and daidzein (DZN) were quantified using enzymatic hydrolysis of plasma samples. The levels of isoflavone glucuronides/sulfates were found to be much greater than that of the corresponding aglycones.  相似文献   
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Stem cell response to a library of scaffolds with varied 3D structures was investigated. Microarray screening revealed that each type of scaffold structure induced a unique gene expression signature in primary human bone marrow stromal cells (hBMSCs). Hierarchical cluster analysis showed that treatments sorted by scaffold structure and not by polymer chemistry suggesting that scaffold structure was more influential than scaffold composition. Further, the effects of scaffold structure on hBMSC function were mediated by cell shape. Of all the scaffolds tested, only scaffolds with a nanofibrous morphology were able to drive the hBMSCs down an osteogenic lineage in the absence of osteogenic supplements. Nanofiber scaffolds forced the hBMSCs to assume an elongated, highly branched morphology. This same morphology was seen in osteogenic controls where hBMSCs were cultured on flat polymer films in the presence of osteogenic supplements (OS). In contrast, hBMSCs cultured on flat polymer films in the absence of OS assumed a more rounded and less-branched morphology. These results indicate that cells are more sensitive to scaffold structure than previously appreciated and suggest that scaffold efficacy can be optimized by tailoring the scaffold structure to force cells into morphologies that direct them to differentiate down the desired lineage.  相似文献   
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