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排序方式: 共有882条查询结果,搜索用时 15 毫秒
81.
MOHSEN EMADEDIN NARGES LABIBZADEH MAEDE GHORBANI LIASTANI ALIASGHAR KARIMI NEDA JAROUGHI TINA BOLURIEH SEYYEDEH-ESMAT HOSSEINI HOSSEIN BAHARVAND NASSER AGHDAMI 《Cytotherapy》2018,20(10):1238-1246
Background
The intra-articular implantation of mesenchymal stromal cells (MSCs) as a treatment for knee osteoarthritis (OA) is an emerging new therapy. In this study, patients with knee OA received intra-articular implantations of autologous bone marrow–derived MSCs. We sought to assess the safety and efficacy of this implantation.Materials and Methods
This was a phase 1/2 single-center, triple-blind, randomized controlled trial (RCT) with a placebo control. The subjects consisted of patients with knee OA randomly assigned to either an intra-articular implantation of MSCs (40?×?106 cells) or 5 mL normal saline (placebo). Patients were followed up for 6 months after the implantations. The pain level and function improvements for patient-reported outcomes were assessed based on a visual analog scale (VAS), Western Ontario and McMaster Universities Arthritis Index (WOMAC) and its subscales, walking distance, painless walking distance, standing time and knee flexion compared with the placebo group at 3 and 6 months following the implantations.Results
Overall, 43 patients (Kellgren-Lawrence grades 2, 3 and 4) were assigned to either the MSCs (n?=?19) or placebo (n?=?24) group. Patients who received MSCs experienced significantly greater improvements in WOMAC total score, WOMAC pain and physical function subscales and painless walking distance compared with patients who received placebo. There were no major adverse events attributed to the MSC therapy.Conclusion
This randomized, triple-blind, placebo-controlled RCT demonstrated the safety and efficacy of a single intra-articular implantation of 40?×?106 autologous MSCs in patients with knee OA. Intra-articular implantation of MSCs provided significant and clinically relevant pain relief over 6 months versus placebo and could be considered a promising novel treatment for knee OA. We propose that further investigations should be conducted over an extended assessment period and with a larger cohort. 相似文献82.
Hilary Ireland Max H.P. Gay Helen Baldomero Barbara De Angelis Hossein Baharvand Mark W. Lowdell Jakob Passweg Ivan Martin 《Cytotherapy》2018,20(1):1-20
Background aims
With the support of five established scientific organizations, this report, the seventh of its kind, describes activity in Europe for the years 2014 and 2015 in the area of cellular and tissue-engineered therapies, excluding hematopoietic stem cell (HSC) treatments for the reconstitution of hematopoiesis.Methods
In 2015 [respectively 2014], 205 [276] teams from 32 countries responded to the cellular and tissue-engineered therapy survey; 178 [126] teams reported treating 3686 [2665] patients.Results
Indications were musculoskeletal/rheumatological disorders (32% [33%]), cardiovascular disorders (12% [21%]), hematology/oncology (predominantly prevention or treatment of graft versus host disease and HSC graft enhancement; 20% [20%]), neurological disorders (4% [6%]), gastrointestinal disorders (<1% [1%]) and other indications (31% [20%]). The majority of autologous cells (60% [73%]) were used to treat musculoskeletal/rheumatological (44% [36%]) disorders, whereas allogeneic cells were used mainly for hematology/oncology (61% [68%]). The reported cell types were mesenchymal stromal cells (40% [49%]), chondrocytes (13% [6%]), hematopoietic stem cells (12% [23%]), dermal fibroblasts (8% [3%]), dendritic cells (2% [2%]), keratinocytes (1% [2%]) and others (24% [15%]). Cells were expanded in vitro in 63% [40%] of the treatments, sorted in 16% [6%] of the cases and rarely transduced (<1%). Cells were delivered predominantly as suspension 43% [51%], intravenously or intra-arterially (30% [30%]), or using a membrane/scaffold (25% [19%]).Discussion
The data are compared with those from previous years to identify trends in a still unpredictably evolving field. Perspectives of representatives from plastic surgery practitioners, Iran and ISCT are presented (contributing authors D.A. Barbara, B. Hossein and W.L. Mark, respectively). 相似文献83.
Witold Wachowiak Annika Perry Kevin Donnelly Stephen Cavers 《Ecology and evolution》2018,8(1):655-666
Closely related taxa occupying different environments are valuable systems for studying evolution. In this study, we examined differences in early phenology (bud set, bud burst) and early growth in a common garden trial of closely related pine species: Pinus sylvestris, P. mugo, and P. uncinata. Seeds for the trial were sourced from populations across the ranges of each species in Europe. Over first 4 years of development, clear differences were observed between species, while the most significant intraspecific differentiation was observed among plants from P. sylvestris populations from continental European locations. Trait differences within P. sylvestris were highly correlated with altitude and latitude of the site of origin. Meanwhile, P. mugo populations from the Carpathians had the earliest bud set and bud flush compared to other populations of the species. Overall, populations from the P. mugo complex from heterogeneous mountain environments and P. sylvestris from the Scottish Highlands showed the highest within‐population variation for the focal traits. Although the three species have been shown to be genetically highly similar, this study reveals large differences in key adaptive traits both among and within species. 相似文献
84.
Blinded and unblinded sample size reestimation procedures for stepped‐wedge cluster randomized trials
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Michael J. Grayling Adrian P. Mander James M. S. Wason 《Biometrical journal. Biometrische Zeitschrift》2018,60(5):903-916
The ability to accurately estimate the sample size required by a stepped‐wedge (SW) cluster randomized trial (CRT) routinely depends upon the specification of several nuisance parameters. If these parameters are misspecified, the trial could be overpowered, leading to increased cost, or underpowered, enhancing the likelihood of a false negative. We address this issue here for cross‐sectional SW‐CRTs, analyzed with a particular linear‐mixed model, by proposing methods for blinded and unblinded sample size reestimation (SSRE). First, blinded estimators for the variance parameters of a SW‐CRT analyzed using the Hussey and Hughes model are derived. Following this, procedures for blinded and unblinded SSRE after any time period in a SW‐CRT are detailed. The performance of these procedures is then examined and contrasted using two example trial design scenarios. We find that if the two key variance parameters were underspecified by 50%, the SSRE procedures were able to increase power over the conventional SW‐CRT design by up to 41%, resulting in an empirical power above the desired level. Thus, though there are practical issues to consider, the performance of the procedures means researchers should consider incorporating SSRE in to future SW‐CRTs. 相似文献
85.
Masoud F. Tavazoie Ilana Pollack Raissa Tanqueco Benjamin N. Ostendorf Bernardo S. Reis Foster C. Gonsalves Isabel Kurth Celia Andreu-Agullo Mark L. Derbyshire Jessica Posada Shugaku Takeda Kimia N. Tafreshian Eric Rowinsky Michael Szarek Roger J. Waltzman Elizabeth A. Mcmillan Connie Zhao Monica Mita Sohail F. Tavazoie 《Cell》2018,172(4):825-840.e18
86.
Estimation of tetrad crossover frequency distributions from genetic recombination data is a classic problem dating back to Weinstein (1936, Genetics 21, 155-199). But a number of important issues, such as how to specify the maximum number of crossovers, how to construct confidence intervals for crossover probabilities, and how to obtain correct p-values for hypothesis tests, have never been adequately addressed. In this article, we obtain some properties of the maximum likelihood estimate (MLE) for crossover probabilities that imply guidelines for choosing the maximum number of crossovers. We give these results for both normal meiosis and meiosis with nondisjunction. We also develop an accelerated EM algorithm to find the MLE more efficiently. We propose bootstrap-based methods to find confidence intervals and p-values and conduct simulation studies to check the validity of the bootstrap approach. 相似文献
87.
Giovanni Mantovani Vittorio Gebbia Mario Airoldi Cesare Bumma Paolo Contu Alessandro Bianchi Massimo Ghiani Daniela Dessì Elena Massa Luigi Curreli Biancarosa Lampis Paola Lai Carlo Mulas Antonio Testa Ernesto Proto Gabrio Cadeddu Giorgio Tore 《Cancer immunology, immunotherapy : CII》1998,47(3):149-156
We carried out an open, randomized, phase III, multicenter clinical trial to compare, in neo-adjuvant setting, the clinical
response and toxicity of the combination chemotherapy cisplatin + 5-FU with the same combination plus s.c. recombinant interleukin-2
(rIL-2) in patients with advanced (stage III–IV) head and neck squamous-cell carcinoma (HNSCC). Regimen A was the classical
Al Sarraf treatment: 100 mg/m2 cisplatin i.v. on day 1 plus 1000 mg m−2 day−1 5-FU on days 1–5 as a continuous infusion. Regimen B was the same as regimen A plus 4.5 MIU/day rIL-2 s.c. on days 8–12 and
15–19. Treatment was repeated every 3 weeks for three cycles. A total of 33 patients were enrolled in the study; 30 were evaluable
for toxicity and 28 for response. Seventeen patients were assigned to group A and 16 were assigned to group B. Three patients
(20%) of group A and 4 (31%) of group B had a complete response, 9 patients (60%) of group A and 6 (46%) of group B had a
partial response, with an overall response rate of 12 patients (80%) for group A and 10 patients (77%) for group B. Two patients
(13%) of group A and 3 patients (23%) group B had stable disease; 1 patient (7%) of group A had progressive disease. Thus,
there was not a statistically significant difference in response rate between the two groups and therefore there was no benefit
from the addition of immunotherapy with rIL-2 to the standard chemotherapy. Both regimens were well tolerated. There were
2 toxic deaths (6.7%), 1 from hematological causes in group A and 1 from cardiac causes in group B. Myelosuppression and gastrointestinal
toxicity, mainly nausea/vomiting and stomatitis, were the most frequent toxicities. The calculated number of patients for
the sample has not yet been reached; however, the projection of our present results suggests that it is highly improbable
that a clinically significant difference between the two treatment groups will be observed even if the calculated patient
sample size is achieved.
Received: 9 April 1998 / Accepted: 30 June 1998 相似文献
88.
89.
90.
【目的】探索0.3%印楝素乳油对梨小食心虫Grapholita molesta的控制效果。【方法】根据梨小食心虫的生物习性,采用浸渍法和浸虫法对梨小食心虫1日龄、3日龄、5日龄的卵和3龄、5龄幼虫进行了杀虫活性测定,采用药膜法对梨小食心虫初孵幼虫进行毒力测定,并通过田间试验测定0.3%印楝素乳油对梨小食心虫的控制效果。【结果】0.3%印楝素乳油对梨小食心虫1日龄、3日龄和5日龄卵的致死中量分别为6.5195、4.5789、6.6268 mg/L,对初孵幼虫的致死中量为6.0495 mg/L,效果较好,而对3龄和5龄幼虫几乎没有杀伤作用。使用有效成分为2.0 mg/kg~3.0 mg/L的印楝素乳油在田间进行梨小食心虫防治试验时,药后5 d和10 d的防治效果在63.18%~76.22%之间,至药后15 d时,防效则下降到27%以下,果实受害明显,表明该药剂已失去控制作用。【结论】印楝素乳油不能作为防治梨小食心虫的专用药剂,仅可在其发生危害的初期,防治其他害虫时,作为兼治的药剂来使用。 相似文献