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991.
Drought tolerance is the essential trait that needs to be incorporated in cereal crops, particularly those grown under the rainfed cultivation. Drought tolerance being contributed by several regions of the genome requires identification of these regions, using suitable molecular markers. Therefore, present investigation was aimed at analyzing the genetic diversity present among the cultivars of rainfed and the irrigated areas with respect to the drought tolerant trait. In all, 14 RAPD and 90 ISSR markers were used to identify these genomic regions. Out of 14 RAPD markers, one RAPD primer exhibited polymorphic banding pattern with 18.6 % polymorphism, clearly separating drought tolerant and drought susceptible genotypes. Out of 90 ISSR primers, only 3 ISSR primers revealed polymorphism in relation to the drought tolerance trait exhibiting 21.38 % polymorphism.  相似文献   
992.
White spot syndrome (WSS) is one of the most common and most disastrous diseases of shrimp worldwide. It causes up to 100% mortality within 3 to 4 days in commercial shrimp farms, resulting in large economic losses to the shrimp farming industry. VP28 envelope protein of WSSV is reported to play a key role in the systemic infection in shrimps. Considering the most sombre issue of viral disease in cultivated shrimp, the present study was undertaken to substantiate the inhibition potential of Avicennia marinaderived phytochemicals against the WSSV envelope protein VP28. Seven A. marina-derived phytochemicals namely stigmasterol, triterpenoid, betulin, lupeol, avicenol-A, betulinic acid and quercetin were docked against the WSSV protein VP28 by using Argus lab molecular docking software. The chemical structures of the phytochemicals were retrieved from Pubchem database and generated from SMILES notation. Similarly the protein structure of the envelope protein was obtained from protein data bank (PDB-ID: 2ED6). Binding sites were predicted by using ligand explorer software. Among the phytochemicals screened, stigmasterol, lupeol and betulin showed the best binding exhibiting the potential to block VP28 envelope protein of WSSV, which could possibly inhibit the attachment of WSSV to the host species. Further experimental studies will provide a clear understanding on the mode of action of these phytochemicals individually or synergistically against WSSV envelope protein and can be used as an inhibitory drug to reduce white spot related severe complications in crustaceans.  相似文献   
993.
For the first time, the Ir(III) catalysis of the iodate oxidation of xylose and maltose in aqueous alkaline medium has been investigated. The reactions exhibit first-order kinetics with respect to lower [IO(3)(-)] and [OH(-)] and show zero-order kinetics at their higher concentrations. Unity order at low concentrations of maltose becomes zero order at its higher concentrations, whereas zero-order kinetics with respect to [xylose] was observed throughout its variation. The reaction rate is found to be directly proportional to [Ir(III)] in the oxidation of both reducing sugars. Negligible effect of [Cl(-)] and nil effect of ionic strength (mu) on the rate of oxidation have also been noted. The species, [IrCl(3)(H(2)O)(2)OH](-) was ascertained as the reactive species of Ir(III) chloride for both the redox systems. Various activation parameters have been calculated. Formic acid and arabinonic acid for maltose and formic acid and threonic acid for xylose were identified as the main oxidation products of the reactions. Mechanisms consistent with the observed kinetic data and spectral evidence have been proposed for the oxidation of xylose and maltose.  相似文献   
994.
Studies on phenology and growing degree days (GDD) of four oil palm crosses, that is, Palode, Deli × Nigeria, United Plantations and Deli × Ghana were conducted in India under tropical conditions. Observations were recorded in adult oil palms over a period of 1.5 years from visual opening of spear leaf to development of female flower till harvest. Biologische Bundesantalt, Bundessortenamt and Chemische Industrie (BBCH) General Scale was used for conducting various phenological growth stages. The GDD from development of spear leaf to maturity in the different crosses varied between 6,320.2 and 6,937.3. The degree days and duration from development of spear leaf to maturity were less in the crosses of United Plantations. The time taken for spear leaf unfolding to maturity and flower opening to maturity in the different crosses, respectively, varied from 447.9 to 485.2 days and 145.8 to 153.7 days. The study gives an insight in evaluating thermal time for achieving various phenophases in oil palm and genotypic variations of time taken in attaining the different phenophases that have been documented. Climatic and yield prediction models can also be evolved through these studies.  相似文献   
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Background:

It is unclear whether participation in a randomized controlled trial (RCT), irrespective of assigned treatment, is harmful or beneficial to participants. We compared outcomes for patients with the same diagnoses who did (“insiders”) and did not (“outsiders”) enter RCTs, without regard to the specific therapies received for their respective diagnoses.

Methods:

By searching the MEDLINE (1966–2010), Embase (1980–2010), CENTRAL (1960–2010) and PsycINFO (1880–2010) databases, we identified 147 studies that reported the health outcomes of “insiders” and a group of parallel or consecutive “outsiders” within the same time period. We prepared a narrative review and, as appropriate, meta-analyses of patients’ outcomes.

Results:

We found no clinically or statistically significant differences in outcomes between “insiders” and “outsiders” in the 23 studies in which the experimental intervention was ineffective (standard mean difference in continuous outcomes −0.03, 95% confidence interval [CI] −0.1 to 0.04) or in the 7 studies in which the experimental intervention was effective and was received by both “insiders” and “outsiders” (mean difference 0.04, 95% CI −0.04 to 0.13). However, in 9 studies in which an effective intervention was received only by “insiders,” the “outsiders” experienced significantly worse health outcomes (mean difference −0.36, 95% CI −0.61 to −0.12).

Interpretation:

We found no evidence to support clinically important overall harm or benefit arising from participation in RCTs. This conclusion refutes earlier claims that trial participants are at increased risk of harm.When people are asked to participate in a randomized controlled trial (RCT), it is natural for them to ask several questions in return. How safe are these treatments? How many extra visits and tests must I undergo? Will the researchers keep my family doctor informed about what’s going on? What outcomes are to be measured, and do they include ones that are of interest to me as a patient?These multiple questions can be summarized as follows: Would I fare better being treated within the trial (as an “insider”) or in routine clinical care outside it (as an “outsider”)? Patients may ask this question in 1 of 2 ways. The first is highly specific: “Am I better off receiving this specific treatment as an insider or as an outsider?” Alternatively, they might ask a more general question: “Am I better off having my illness managed, regardless of the specific treatment I would receive, as an insider or as an outsider?” These questions are highly appropriate, and both deserve to be asked and answered,1,2 especially given that nonsystematic reviews have suggested a possible “inclusion benefit” from participating in trials.3These 2 specific patient questions are analogous to those posed by researchers asking whether treatments do more good than harm when applied under “ideal” circumstances (in explanatory trials) or in the “real world” of routine health care (in pragmatic trials). Vist and colleagues answered the explanatory question when their earlier review4 found no advantage or disadvantage from receiving the same treatment inside or outside an RCT. Left unanswered, however, was the broader, more pragmatic question. In our experience, trial participants are often offered new, as-yet-untested treatments that would not be available to them outside the trial. This review looks at the dilemma faced by these patients, which needs to be addressed before general conclusions can be drawn about trial safety.  相似文献   
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Metastasis of renal cell carcinoma (RCC) to the nasal cavity and paranasal sinuses is rare, with fewer than 50 cases described in the literature. Nasal metastasis as the initial presentation of RCC is even rarer. Metastases to the nasal cavity usually represent advanced disease with poor outcome. The authors report a case of metastatic RCC presenting with right nasal cavity mass and epistaxis, followed by a brief review of the relevant literature.Key words: Renal cell carcinoma, Nasal metastasis, EpistaxisRenal cell carcinoma (RCC) accounts for approximately 85% of primary renal tumors, and represents approximately 3% of all adult malignancies.1 Usual sites of metastasis include lungs (75%), regional lymph nodes (65%), bone (40%), liver (40%), and brain (5%).2 Metastasis to the nasal cavity is an extremely rare occurrence, with fewer than 50 cases reported,3,4 although RCC is the most common infraclavicular primary tumor that metastasizes to the nasal cavity and paranasal sinuses.5 We describe a case of occult clear-cell RCC that presented with epistaxis due to nasal cavity metastasis.  相似文献   
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