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排序方式: 共有1732条查询结果,搜索用时 46 毫秒
1.
Yilmaz Hülya Fırtına Sinem Sarıtaş Merve Sayitoğlu Müge Ar Muhlis Cem 《Immunologic research》2022,70(6):811-816
Immunologic Research - Hyper immunoglobulin M (HIGM) syndrome is a rare disorder of the immune system with impaired antibody functions. The clinical picture of the patients varies according to the... 相似文献
2.
Sina V. Jostes Martin Fellermeyer Lena Arévalo Gina E. Merges Glen Kristiansen Daniel Nettersheim Hubert Schorle 《International journal of cancer. Journal international du cancer》2020,146(6):1592-1605
Embryonal carcinomas (ECs) and seminomas are testicular germ cell tumors. ECs display expression of SOX2, while seminomas display expression of SOX17. In somatic differentiation, SOX17 drives endodermal cell fate. However, seminomas lack expression of endoderm markers, but show features of pluripotency. Here, we use chromatin immunoprecipitation sequencing to report and compare the binding pattern of SOX17 in seminoma-like TCam-2 cells to SOX17 in somatic cells and SOX2 in EC-like 2102EP cells. In seminoma-like cells, SOX17 was detected at canonical (SOX2/OCT4), compressed (SOX17/OCT4) and noncomposite SOX motifs. SOX17 regulates TFAP2C, PRDM1 and PRDM14, thereby maintaining latent pluripotency and suppressing somatic differentiation. In contrast, in somatic cells canonical motifs are rarely bound by SOX17. In sum, only 12% of SOX17-binding sites overlap in seminoma-like and somatic cells. This illustrates that binding site choice is highly dynamic and cell type specific. Deletion of SOX17 in seminoma-like cells resulted in loss of pluripotency, marked by a reduction of OCT4 protein level and loss of alkaline phosphatase activity. Furthermore, we found that in EC-like cells SOX2 regulates pluripotency-associated genes, most likely by partnering with OCT4. In conclusion, SOX17 (in seminomas) functionally replaces SOX2 (in ECs) to maintain expression of the pluripotency cluster. 相似文献
3.
Niki Oikonomopoulou Concepción Míguez-Navarro Arístides Rivas-García Mercedes García Gamiz Rosario López-López Paloma Oliver-Sáez Bibiana Riaño-Méndez Tamara Farfan-Orte Zulema Lobato-Salinas Júlia Rúbies-Olives Priscila Llena-Isla Encarnación María Lancho-Monreal 《The American journal of emergency medicine》2019,37(7):1289-1294
BackgroundAcute appendicitis (AA) is one of the most frequent surgical pathologies in pediatrics.ObjectivesTo investigate the utility of proadrenomedullin (pro-ADM) for the diagnosis of AA.MethodsProspective, analytical, observational, and multicenter study conducted in 6 pediatric emergency departments. Children up to 18 years of age with suspected AA were included. Clinical, epidemiological, and analytical data were collected.ResultsWe studied 285 children with an average age of 9.5 years (95% confidence interval [CI], 9.1–9.9). AA was diagnosed in 103 children (36.1%), with complications in 10 of them (9.7%). The mean concentration of pro-ADM (nmol/L) was higher in children with AA (0.51 nmol/L, SD 0.16) than in children with acute abdominal pain (AAP) of another etiology (0.44 nmol/L, SD 0.14; p < 0.001). This difference was greater in complicated cases compared with uncomplicated AA (0.64 nmol/L, SD 0.17 and 0.50 nmol/L, SD 0.15, respectively; p = 0.005). The areas under the receiver-operating characteristic curves were 0.66 (95% CI, 0.59–0.72) for pro-ADM, 0.70 (95% CI, 0.63–0.76) for C-reactive protein (CRP), 0.84 (95% CI, 0.79–0.89) for neutrophils, and 0.84 (95% CI, 0.79–0.89) for total leukocytes. The most reliable combination to rule out AA was CRP ≤1.25 mg/dL and pro-ADM ≤0.35 nmol/L with a sensitivity of 96% and a negative predictive value of 93%.ConclusionChildren with AA presented higher pro-ADM values than children with AAP of other etiologies, especially in cases of complicated AA. The combination of low values of pro-ADM and CRP can help to select children with low risk of AA. 相似文献
4.
Enrique Cabrera Torres María Aránzazu García Iglesias María Teresa Santos Jiménez Miguel González Hierro María Luisa Diego Domínguez 《Gaceta sanitaria / S.E.S.P.A.S》2019,33(1):32-37
Objective
To analyze the relationship between the type of hospital admission (outlier and non-outlier admissions) and the appearance of clinical complications and the average stay.Methods
From a retrospective epidemiological study of a cohort of patients admitted to the Hospital Complejo Asistencial Universitario de Salamanca (Salamanca, Spain) over a six-month period, outlier and non-outlier patients were identified. This project had access to the admissions department database, the hospital's CMBD (in Spanish, Conjunto Mínimo Básico de Datos) for hospitalisation, the AP-DRG (All Patient-Diagnosis Related Groups) and ALCOR (a clinical-statistics analytics tool). It then proceeded to break down the results by DRG, looking at the five most common DRGs in that period.Results
8.4% of the total 11,842 admissions were medical outliers. In the overall study, the average stay was longer for outlier patients (8. 11 days) than for other patients (7.15 days). The mortality rate was, likewise, higher for outlier patients, although there was a reduced incidence of complications (7.6% for outlier patients as opposed to 8.4% for others). The analysis by DRG corroborated these results in three of the five cases investigated, showing longer average stays but fewer clinical complications in the case of outlier patients.Conclusions
On admission to hospital, a significant proportion of patients were allocated beds on inappropriate wards (outlier patients). It was more common to find medical patients placed on surgical wards than vice versa. The average stay of outlier patients was longer than that of patients admitted to the correct ward. The study found no significant difference between the two group? in terms of clinical complication rates. 相似文献5.
6.
Arístides A. Pochettino María Belén Hapon Silvana M. Biolatto María José Madariaga Graciela A. Jahn Cintia N. Konjuh 《Drug and chemical toxicology》2016,39(4):392-399
The herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) is used on a wide variety of terrestrial and aquatic broadleaf weeds. 2,4-D has been shown to produce a wide range of adverse effects on animal and human health. The aim of the current study was to evaluate the effects of pre- and postnatal exposure to 2,4-D on rat ventral prostate (VP). Pregnant rats were exposed daily to oral doses of 70?mg/kg/day of 2,4-D from 16 days of gestation up to 23 days after delivery. Then, the treated groups (n?=?8) were fed with a 2,4-D added diet until sacrificed by decapitation on postnatal day (PND) 45, 60, or 90. Morphometric studies were performed and androgen receptor (AR) protein levels in the VP were determined. AR, insulin-like growth factor-I (IGF-1) and insulin-like growth factor-I receptor (IGF-1R) mRNA expression in the VP along with testosterone (T), dihydroxytestosterone (DHT), growth hormone (GH) and IGF-1 serum levels were also determined to ascertain whether these parameters were differentially affected. Results of this study showed that 2,4-D exposure during gestation and until adulthood altered development of the prostate gland in male rats, delaying it at early ages while increasing its size in adults, indicate that 2,4-D could behave as endocrine disruptors (EDs). 相似文献
7.
Extraction of artefactual MRS patterns from a large database using non-negative matrix factorization
Yanisleydis Hernández-Villegas Sandra Ortega-Martorell Carles Arús Alfredo Vellido Margarida Julià-Sapé 《NMR in biomedicine》2022,35(4):e4193
Despite the success of automated pattern recognition methods in problems of human brain tumor diagnostic classification, limited attention has been paid to the issue of automated data quality assessment in the field of MRS for neuro-oncology. Beyond some early attempts to address this issue, the current standard in practice is MRS quality control through human (expert-based) assessment. One aspect of automatic quality control is the problem of detecting artefacts in MRS data. Artefacts, whose variety has already been reviewed in some detail and some of which may even escape human quality control, have a negative influence in pattern recognition methods attempting to assist tumor characterization. The automatic detection of MRS artefacts should be beneficial for radiology as it guarantees more reliable tumor characterizations, as well as the development of more robust pattern recognition-based tumor classifiers and more trustable MRS data processing and analysis pipelines. Feature extraction methods have previously been used to help distinguishing between good and bad quality spectra to apply subsequent supervised pattern recognition techniques. In this study, we apply feature extraction differently and use a variant of a method for blind source separation, namely Convex Non-Negative Matrix Factorization, to unveil MRS signal sources in a completely unsupervised way. We hypothesize that, while most sources will correspond to the different tumor patterns, some of them will reflect signal artefacts. The experimental work reported in this paper, analyzing a combined short and long echo time 1H-MRS database of more than 2000 spectra acquired at 1.5T and corresponding to different tumor types and other anomalous masses, provides a first proof of concept that points to the possible validity of this approach. 相似文献
8.
Kalender Arıkan Zeynep Yaşar Arıkan Salih Levent Turan 《Bulletin of environmental contamination and toxicology》2018,100(3):361-368
The residues of persistent organochlorinated pollutants (POPs), namely polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) (HCHs, CHLs, HCCPs, DDTs, and dicofol congeners) were investigated in the hair and muscle of road-killed Erinaceus roumanicus and E. concolor in Turkey. Mean residue levels were as follows: in hair, PCBs?=?7.43?±?4.88 ng/g and OCPs?=?9.21?±?1.27 ng/g; in muscle, PCBs?=?30.73?±?2.51 ng/g and OCPs?=?145.04?±?16.59 ng/g. There was no significant difference between species and sex, while there was significant difference between habitats and regions in terms of either total PCB and OCP levels, or POP levels (p?<?0.05). Age was a determinative factor for the bio-accumulation of POPs. The contaminant levels were high in the species, sample areas, and habitats. The data also showed that tissues of hedgehogs are suitable for monitoring and evaluating the bioaccumulation of POP levels in Turkey. 相似文献
9.
Nerea Becerra-Tomás Andrés Díaz-López Núria Rosique-Esteban Emilio Ros Pilar Buil-Cosiales Dolores Corella Ramon Estruch Montserrat Fitó Lluís Serra-Majem Fernando Arós Rosa Maria Lamuela-Raventós Miquel Fiol José Manuel Santos-Lozano Javier Díez-Espino Olga Portoles Jordi Salas-Salvadó 《Clinical nutrition (Edinburgh, Scotland)》2018,37(3):906-913
10.