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Exposure of iminodipropionitrile (IDPN) to rodents produces permanent behavioral syndrome characterized by repetitive head movements, circling and back walking. Other synthetic nitriles of industrial importance such as crotonitrile and allylnitrile are also able to produce similar motor deficits in experimental animals. However, due to the well-defined behavioral deficits and their easy quantification, IDPN-induced behavioral syndrome is a preferential animal model to test the interaction of various agents with synthetic nitriles. This study reports the effect of non-specific nitric oxide synthase inhibitor, N-nitro-l-arginine (NARG) on IDPN-induced neurobehavioral toxicity in adult male Wistar rats. Four groups of animals were given i.p. injections of IDPN (100 mg/kg) for 6 days. These rats were treated with oral administration of NARG in the doses of 0 (IDPN alone group), 50, 150 and 300 mg/kg, 60 min before IDPN, respectively. Control rats received vehicle only, whereas another group was treated with 300 mg/kg of NARG alone (without IDPN). The results showed that NARG significantly exacerbated the incidence and intensity of IDPN-induced dyskinetic head movements, circling and back walking. The histology of inner ear showed massive degeneration of the sensory hair cells in the crista ampullaris of rats receiving the combined treatment with IDPN and NARG, suggesting a possible role of nitric oxide in IDPN-induced neurobehavioral syndrome in rats.  相似文献   
154.
Mercury (Hg) contamination of wastewater streams as a result of anthropogenic activities is a great threat to living organisms due to its acute toxicity. Therefore, current research is focused on the development of effective remediation technologies to protect human health and the environment. In this study, a novel chemical modification route was applied for the multi-functionalization of biochar in order to make it more efficient and selective for Hg(ii) removal from aqueous solution. The amino-grafted modified biochar (AMBC) having multifunctional groups on its surface was successfully synthesized through the activation of excessively available carboxylic groups (–COOH) on pre-oxidized biochar (BC–COOH). The maximum Hg(ii) adsorption capacity for the optimized amino-BC2 sample was 14.1 mg g−1, which was almost twice as that for pristine biochar (BC, 7.1 mg g−1). SEM, FTIR, and XPS techniques were applied for the confirmation of chemically grafted amino groups as well as the presence of residual –COOH groups on the biochar surface. Based on the batch adsorption data, adsorption kinetics and isotherms as well as XPS results, it was concluded that the Hg(ii) removal mechanism was purely driven by chemisorption such as electrostatic interaction, surface complexation, ion exchange with no precipitation and crystalline material being adsorbed on the adsorbent surface. These research findings not only provide a suitable adsorbent for decontamination of Hg(ii) from aqueous solution but also offer a new route for the multi-functionalization of biochar in order to make environment-friendly and inexpensive adsorbents.

Mercury (Hg) contamination of wastewater streams as a result of anthropogenic activities is a great threat to living organisms due to its acute toxicity.  相似文献   
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An association between human papillomavirus (HPV) infection and the development of cervical cancer was initially suggested over 30 years ago, and today there is clear evidence that certain subtypes of HPV are the causative agents of such malignancies. Papillomaviruses make up a vast family that comprises hundreds of different viruses. These viruses infect epithelia in humans and animals and cause benign hyperproliferative lesions, commonly called warts or papillomas, which can occasionally progress to squamous cell cancer. HPV infections are considered the most common among sexually transmitted diseases. One of the most prevalent cancer types induced by HPV (mostly types 16 and 18) is cervical cancer. Vaccination is the most effective means of preventing this infectious disease. These prophylactic vaccines, based on virus-like particles (VLPs), are extremely effective in providing protection from infection in almost 100 % of cases. VLP vaccines of HPV are subunit vaccines consisting only of the major viral capsid protein of HPV. There are two types of vaccine available: bivalent vaccine (against HPV-16/18) and quadrivalent vaccine (against HPV-6/11/16/18). Second-generation prophylactic HPV vaccines, currently in clinical trials, may hold several merits over the current bivalent and quadrivalent vaccines, such as protection against additional oncogenic HPV types, less dependence on cold-chain storage and distribution, and non-invasive methods of delivery.  相似文献   
157.

Purpose

Use of thoracic epidural analgesia (TEA) with local anesthetic and adjuncts, such as opioids, are cornerstones of ERAS (Enhanced Recovery After Surgery) and are considered to play a key role in recovery after colorectal surgery. However, its effect on bowel function may lead to prolong hospital stay and is still a matter of debate. The purpose of this systemic review was to assess whether epidural analgesia could have a detrimental effect on bowel function in laparoscopic colorectal surgery with a subsequent effect on hospital stay duration, leading to failure of ERAS in colorectal surgery.

Methods

A systematic review of randomized, controlled trials for the effect of epidural analgesia on laparoscopic colorectal surgery was performed. The effect on postoperative recovery was evaluated in terms of return of bowel function as the primary outcome, whereas length of stay (LOS), pain score on visual analogue scale, operative time, and incidence of postoperative complications and side-effects of analgesia were recorded as secondary outcomes.

Results

Six trials published between 1999 and 2011 were included in the final analysis. TEA significantly improves return of bowel function assessed by time to first bowel motion [WMD ?0.62 (?1.11, ?0.12) with Z = 2.43; P = 0.02, 95 % confidence interval (CI)], and pain scores [WMD ?1.23 (?2.4, ?0.07)] with Z = 2.07; P = 0.04, 95 % CI]. TEA did not influence duration of hospital stay [WMD ?0.47 (?1.55, 0.61)] with Z = 0.85 (P = 0.39, 95 % CI). No significant increase in operative time or side effects was associated with TEA.

Conclusions

Despite of some beneficial effect of epidural analgesia on return of bowel function and pain in laparoscopic surgery, it does not affect LOS, which is multifactorial.  相似文献   
158.
Purpose: This study was aimed to develop a simple and user-friendly software for fast and accurate computation of normal tissue complication probability (NTCP) in accordance with the Lyman model.

Materials and methods: The software CalcNTCP has been developed in Visual Basic and is equipped with two functional modes. Mode 1 is based on pre-stored values of various parameters for 27 different organ systems and the user has only to input the values of volume fraction (v) and radiation dose (D), whereas Mode 2 is designed for the customized entries.

Results: The results of software validation have demonstrated that CalcNTCP is more efficient and time-saving as compared to manual or semi-manual procedures. The shapes and locations of representative survival curves generated by CalcNTCP-based computations for various radiation doses (10 – 100 Gy) and reference volumes (0.33 – 1.00) absolutely matched with optimal curves.

Conclusion: CalcNTCP is a simple, fast and accurate tool for the computation of NTCP with a direct implication in the evaluation or optimization of radiotherapy treatment plans.  相似文献   
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Trypanosoma cruzi infects all nucleated cells in both humans and experimental animals. As a prelude to our studies of T. cruzi pathogenesis in the gastrointestinal system, we have initiated in vitro cultures of gut (Caco-2 and HT-29) and pancreatic (Panc-1) epithelial cells. We show that along with primary human fibroblasts, all three cell lines are susceptible to infection and support proliferation of T. cruzi. Infection with T. cruzi modified dramatically the cytokines elaborated by these cells. Substantially greater quantities of IL-5 and TGF-β1 were produced by fibroblasts and Caco-2 and Panc-1 cells, whereas secretion of IFN-γ and TNF-α was greatly reduced in all three cell types. Since these cells are not known to be the primary sources of IFN-γ, we examined IFN-γ mRNA expression in these cells. Both Caco-2 and Panc-1 cells were found to express IFN-γ mRNA, validating its secretion. These findings may provide insight into signaling pathways that mediate innate immunity to T. cruzi and pathogenesis of gastrointestinal and pancreatic alterations in Chagas disease.  相似文献   
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