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51.
GDNF increases the survival of developing oculomotor neurons through a target-derived mechanism 总被引:2,自引:0,他引:2
Glial cell line-derived neurotrophic factor (GDNF) is the most potent motoneuron survival factor. We show here that in the chick oculomotor system, endogenous GDNF is derived largely from extraocular muscle but less from glial cells and not from muscle spindles. Increased levels of GDNF exclusively in the target rescued 30% of oculomotor neurons that would normally die during developmental cell death, a rate of rescue similar to that with systemic GDNF application. Thus, GDNF supports motoneuron survival in a retrograde, target-derived fashion, as opposed to a local paracrine route or an indirect route via sensory afferents. Persephin, another member of the GDNF family, did not increase survival with target delivery, despite its retrograde transport from the target. Unlike GDNF, however, persephin increased neurite outgrowth from oculomotor nuclei in vitro. Thus, one GDNF family member acts as a muscle-derived retrograde survival factor, whereas another one has distinct functions on neurite outgrowth. 相似文献
52.
Restoring E-cadherin expression increases sensitivity to epidermal growth factor receptor inhibitors in lung cancer cell lines 总被引:13,自引:0,他引:13
53.
Loss of heterozygosity at chromosomes 3p and 17p in primary non-small cell lung cancer 总被引:2,自引:0,他引:2
Chmara M Wozniak A Ochman K Kobierska G Dziadziuszko R Sosinska-Mielcarek K Jassem E Skokowski J Jassem J Limon J 《Anticancer research》2004,24(6):4259-4263
BACKGROUND: Loss of heterozygosity (LOH) of selected regions at chromosomes 3p and 17p in non-small cell lung cancer (NSCLC) and the association of these abnormalities with major clinical parameters and prognosis were studied. MATERIALS AND METHODS: The study group included 92 consecutive primary NSCLC tumours and four microsatellite markers from chromosome 3p and three markers from 17p were analyzed. RESULTS: LOH of at least one locus was found in 83% of all analyzed tumours. Most frequently deletion (58%) was found at locus D3S1481 (3p14.2). Sequence deletions of D17S520 (17p12) and TP53 (17p13.1) occurred in 52% of tumours. LOH occurrence at 3p and 17p was more frequent in squamous cell carcinomas compared to adenocarcinomas (89% vs. 75%), but this difference was not significant. CONCLUSION: No significant association was found between LOH on any analyzed loci and tumour stage (TNM) and grade (G). There was no correlation between LOH and survival. 相似文献
54.
Rafal Watrowski Christoph Jäger Monika Gerber Catherina Klein 《European journal of pediatrics》2014,173(11):1407-1412
Subocclusive hymenal variants, such as microperforate or septate hymen, impair somatic functions (e.g., vaginal intercourse or menstrual hygiene) and can negatively impact the quality of life of young women. We know little about the prevalence and inheritance of subocclusive hymenal variants. So far, eight cases of familial occurrence of occlusive hymenal anomalies (imperforate hymen) have been reported. In one of these cases, monozygotic twins were affected. We are reporting the first case of subocclusive hymenal variants (microperforate hymen and septate hymen) in 16-year-old white dizygotic twins. In addition, we review and discuss the current evidence. Conclusion: The mode of inheritance of hymenal variants has not been determined so far. Because surgical corrections of hymenal variants should be carried out in asymptomatic patients (before menarche), gynecologists and pediatricians should keep in mind that familial occurrences may occur. 相似文献
55.
Peter R. Buseck Rafal E. Dunin-Borkowski Bertrand Devouard Richard B. Frankel Martha R. McCartney Paul A. Midgley Mihly Psfai Matthew Weyland 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(24):13490-13495
Nanocrystals of magnetite (Fe(3)O(4)) in a meteorite from Mars provide the strongest, albeit controversial, evidence for the former presence of extraterrestrial life. The morphological and size resemblance of the crystals from meteorite ALH84001 to crystals formed by certain terrestrial bacteria has been used in support of the biological origin of the extraterrestrial minerals. By using tomographic and holographic methods in a transmission electron microscope, we show that the three-dimensional shapes of such nanocrystals can be defined, that the detailed morphologies of individual crystals from three bacterial strains differ, and that none uniquely match those reported from the Martian meteorite. In contrast to previous accounts, we argue that the existing crystallographic and morphological evidence is inadequate to support the inference of former life on Mars. 相似文献
56.
Meike M.C. Hirdes Tom P.V.M. de Jong Pieter Dik Marianne A.W. Vijverberg Rafal Chrzan Aart J. Klijn 《Journal of pediatric urology》2010,6(4):372-375
PurposeTo investigate systematically the length of the urethra in girls with lower urinary tract symptoms.Materials and methodsIn a group of 121 consecutive girls presented at a tertiary referral clinic for urinary incontinence or recurrent urinary tract infections, urethral length was measured by perineal ultrasound. The urethra was measured with the patient in supine position without anesthesia. Mean age of the patients was 7.8 (0–15) years.ResultsAverage urethral length was 26 mm. Minimum length was 12 mm, measured in a 5-year-old girl with dribbling incontinence. Maximum measured length was 40 mm in a 15-year-old girl. In four girls (3.3%), aged 1–10 years (mean 6.3), a short urethra was detected, with measured lengths of 12 and 14 mm. All four had normal genitalia, and were referred with therapy-resistant urinary incontinence or urinary tract infections. A gradual increase in average urethral length was measured from 23 mm at birth to 32 mm at 15 years.ConclusionUrethral length can be measured accurately by ultrasound. Although a short urethral length is rarely detected by ultrasound in girls with incontinence, it may be associated with therapy-resistant incontinence. In such cases, different treatment options are available. 相似文献
57.
Adam Czyzyk Justyna Latacz Dorota Filipowicz Agnieszka Podfigurna Rafal Moszynski Piotr Jasinski 《Gynecological endocrinology》2017,33(11):836-839
Ovarian hyperthecosis (OH) is characterized by the presence of abundant luteinized theca cells in ovaries that secret androgen. It typically presents as severe hyperandrogenism and/or virilization in postmenopausal woman. Here we describe a 66-year old woman with presentation of severe hirsutism, alopecia, clitoromegaly and laboratory finding of significantly elevated serum total testosterone concentration and hyperinsulinemia. Performed imaging studies revealed normal sized, homogeneous ovaries, signs of endometrial hypertrophy and normal adrenal glands. Due to severe hyperandrogenemia and signs of endometrial hypertrophy, the total abdominal hysterectomy with bilateral salpingo-oophorectomy has been performed. Pathological examination revealed OH and endometrial hyperplasia. Androgenic activity of ovarian stromal cells has been confirmed using alpha-inhibin histochemical staining. Postmenopausal hyperandrogenemia is a diagnostic and therapeutic challenge and the imaging studies often may be misleading and require careful and critical consideration. 相似文献
58.
59.
Christoph Globas MD Sophie Tezenas du Montcel MD PhD Laslo Baliko MD Syliva Boesch MD Chantal Depondt MD Stefano DiDonato MD Alexandra Durr MD Alessandro Filla MD Thomas Klockgether MD Caterina Mariotti MD Bela Melegh MD PhD Maryla Rakowicz MD Pascale Ribai MD Rafal Rola MD Tanja Schmitz‐Hubsch MD Sandra Szymanski MD Dagmar Timmann MD Bart P. Van de Warrenburg MD Peter Bauer MD Ludger Schols MD 《Movement disorders》2008,23(15):2232-2238
Onset of genetically determined neurodegenerative diseases is difficult to specify because of their insidious and slowly progressive nature. This is especially true for spinocerebellar ataxia (SCA) because of varying affection of many parts of the nervous system and huge variability of symptoms. We investigated early symptoms in 287 patients with SCA1, SCA2, SCA3, or SCA6 and calculated the influence of CAG repeat length on age of onset depending on (1) the definition of disease onset, (2) people defining onset, and (3) duration of symptoms. Gait difficulty was the initial symptom in two‐thirds of patients. Double vision, dysarthria, impaired hand writing, and episodic vertigo preceded ataxia in 4% of patients, respectively. Frequency of other early symptoms did not differ from controls and was regarded unspecific. Data about disease onset varied between patients and relatives for 1 year or more in 44% of cases. Influence of repeat length on age of onset was maximum when onset was defined as beginning of permanent gait disturbance and cases with symptoms for more than 10 years were excluded. Under these conditions, CAG repeat length determined 64% of onset variability in SCA1, 67% in SCA2, 46% in SCA3, and 41% in SCA6 demonstrating substantial influence of nonrepeat factors on disease onset in all SCA subtypes. Identification of these factors is of interest as potential targets for disease modifying compounds. In this respect, recognition of early symptoms that develop before onset of ataxia is mandatory to determine the shift from presymptomatic to affected status in SCA. © 2008 Movement Disorder Society 相似文献
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