全文获取类型
收费全文 | 15137篇 |
免费 | 780篇 |
国内免费 | 151篇 |
专业分类
耳鼻咽喉 | 121篇 |
儿科学 | 414篇 |
妇产科学 | 349篇 |
基础医学 | 1983篇 |
口腔科学 | 338篇 |
临床医学 | 1168篇 |
内科学 | 3795篇 |
皮肤病学 | 381篇 |
神经病学 | 1657篇 |
特种医学 | 668篇 |
外科学 | 2085篇 |
综合类 | 56篇 |
预防医学 | 710篇 |
眼科学 | 238篇 |
药学 | 909篇 |
中国医学 | 45篇 |
肿瘤学 | 1151篇 |
出版年
2024年 | 22篇 |
2023年 | 153篇 |
2022年 | 299篇 |
2021年 | 477篇 |
2020年 | 267篇 |
2019年 | 355篇 |
2018年 | 451篇 |
2017年 | 330篇 |
2016年 | 392篇 |
2015年 | 459篇 |
2014年 | 563篇 |
2013年 | 721篇 |
2012年 | 1088篇 |
2011年 | 1139篇 |
2010年 | 672篇 |
2009年 | 626篇 |
2008年 | 973篇 |
2007年 | 988篇 |
2006年 | 992篇 |
2005年 | 941篇 |
2004年 | 907篇 |
2003年 | 835篇 |
2002年 | 712篇 |
2001年 | 137篇 |
2000年 | 109篇 |
1999年 | 142篇 |
1998年 | 140篇 |
1997年 | 128篇 |
1996年 | 96篇 |
1995年 | 85篇 |
1994年 | 63篇 |
1993年 | 68篇 |
1992年 | 51篇 |
1991年 | 49篇 |
1990年 | 50篇 |
1989年 | 56篇 |
1988年 | 57篇 |
1987年 | 52篇 |
1986年 | 43篇 |
1985年 | 38篇 |
1984年 | 37篇 |
1983年 | 32篇 |
1982年 | 31篇 |
1981年 | 20篇 |
1980年 | 15篇 |
1979年 | 27篇 |
1977年 | 15篇 |
1974年 | 16篇 |
1970年 | 13篇 |
1967年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Gabriele Piuri Monica Zocchi Matteo Della Porta Valentina Ficara Michele Manoni Gian Vincenzo Zuccotti Luciano Pinotti Jeanette A. Maier Roberta Cazzola 《Nutrients》2021,13(2)
Magnesium (Mg2+) deficiency is probably the most underestimated electrolyte imbalance in Western countries. It is frequent in obese patients, subjects with type-2 diabetes and metabolic syndrome, both in adulthood and in childhood. This narrative review aims to offer insights into the pathophysiological mechanisms linking Mg2+ deficiency with obesity and the risk of developing metabolic syndrome and type 2 diabetes. Literature highlights critical issues about the treatment of Mg2+ deficiency, such as the lack of a clear definition of Mg2+ nutritional status, the use of different Mg2+ salts and dosage and the different duration of the Mg2+ supplementation. Despite the lack of agreement, an appropriate dietary pattern, including the right intake of Mg2+, improves metabolic syndrome by reducing blood pressure, hyperglycemia, and hypertriglyceridemia. This occurs through the modulation of gene expression and proteomic profile as well as through a positive influence on the composition of the intestinal microbiota and the metabolism of vitamins B1 and D. 相似文献
52.
Alice Ramondetta Simone Ribero Pietro Quaglino Paolo Broganelli 《Emerging infectious diseases》2021,27(1):281
Fluorescence-advanced videodermatoscopy is not a widespread diagnostic technique. Its application in dermatology can facilitate the diagnosis of diseases such as cutaneous larva migrans by enabling us to recognize the precise position of larva in vivo on the skin. Using this noninvasive technique, we detected a case of cutaneous larva migrans in a patient. 相似文献
53.
Anania Pasquale Battaglini Denise Balestrino Alberto DAndrea Alessandro Prior Alessandro Ceraudo Marco Rossi Diego Criminelli Zona Gianluigi Fiaschi Pietro 《Neurosurgical review》2021,44(3):1243-1253
Neurosurgical Review - Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after... 相似文献
54.
55.
Rachel Wuerstlein Nadia Harbeck Eva-Maria Grischke Dirk Forstmeyer Raquel von Schumann Petra Krabisch Kerstin Lüdtke-Heckenkamp Andrea Stefek Oliver Stoetzer Andrea Grafe Gabriele Kaltenecker Helmut Forstbauer Doris Augustin Iris Schrader Joke Tio Ulrike Nitz Oleg Gluz Ronald E. Kates Monika Karla Graeser 《Breast care (Basel, Switzerland)》2021,16(1):50
BackgroundProtroca evaluated the efficacy and safety of primary and secondary prophylaxis of neutropenia with lipegfilgrastim (Lonquex®) in breast cancer patients receiving neoadjuvant or adjuvant chemotherapy (CT).Patients and MethodsOf the 255 patients enrolled, 248 patients were evaluable for the intent-to-treat (ITT) and 194 patients for the per-protocol set. Primary and secondary end points after lipegfilgrastim treatment were assessed.ResultsNine patients of the ITT set receiving lipegfilgrastim as primary prophylaxis (n = 222) had febrile neutropenia of grade 3–4 (5 patients) or infection of grade 3–4 (4 patients); 1/26 of those receiving secondary prophylaxis had an event. Dose reductions were performed in 9.5% of the patients. Postponement of cancer CT cycles for >3 days occurred in <15% of patients; 10.8% (92/851 AEs) and 8% (2/25 SAEs) of documented adverse events and serious adverse events, respectively, were related to lipegfilgrastim.ConclusionsApplication of lipegfilgrastim was effective as primary and secondary prophylaxis in the prevention of CT-induced neutropenia in breast cancer. 相似文献
56.
ACE inhibition reduces activity of the plasminogen/plasmin and MMP systems in the brain of spontaneous hypertensive stroke-prone rats 总被引:2,自引:0,他引:2
Liebetrau M Burggraf D Wunderlich N Jäger G Linz W Hamann GF 《Neuroscience letters》2005,376(3):205-209
The spontaneously hypertensive stroke-prone rat (SHR-SP) is an experimental model of malignant hypertension which lead to secondary alterations of the extracellular matrix. Our aim was to determine ACE-inhibitor related changes of proteases involved in the reconstruction of the extracellular matrix in the brain. Twelve SHR-SP rats were randomized into two groups. Each group was treated with either an antihypertensive dose of ramipril or placebo for 6 months. Brain tissue plasminogen activator (t-PA) and urokinase (u-PA) were quantified by using casein-dependent plasminogen zymography, matrix metalloproteinase (MMP)-2 and MMP-9, by MMP-zymography, and tissue inhibitor of MMP (TIMP)-1 and -2, by reverse zymography. The amounts of u-PA, t-PA, and MMPs were significantly reduced in animals treated with ACE inhibitor. Plasminogen zymography showed a 39% reduction of u-PA in the basal ganglia (p < 0.0001); t-PA expression was reduced by 26% in the cortex and by 33% in the basal ganglia (p < 0.0001). MMP-2 expression was reduced by 15% in the cortex (p < 0.05) and by 10% in the basal ganglia (p < 0.05); MMP-9 expression significantly decreased by 37% in the cortex and by 25% in the basal ganglia (p < 0.0001 each). No differences were observed in the amount of TIMP-1 or TIMP-2. These findings provide new insights into the biochemical mechanisms underlying extracellular matrix proliferation and its modulation by ACE inhibitors. Therapeutic alterations that influence the proteolytic systems might prove important in the prevention of extracellular matrix accumulation and secondary microvascular vessel wall changes. 相似文献
57.
Nocturnal Paroxysmal Dystonia with Short-Lasting Attacks: Three Cases with Evidence for an Epileptic Frontal Lobe Origin of Seizures 总被引:9,自引:6,他引:3
Paolo Tinuper Angelina Cerullo Fabio Cirignotta Pietro Cortelli Elio Lugaresi Pasquale Montagna 《Epilepsia》1990,31(5):549-556
The epileptic or nonepileptic origin of nocturnal paroxysmal dystonia (NPD) has been debated. We studied three patients with frequent attacks during non-REM sleep. During prolonged video-EEG monitoring, two patients had a convulsive seizure after a typical NPD episode and on these occasions EEG showed epileptiform discharge. In the three patients, attacks occurred repeatedly with different intensity, representing "fragments" of the same seizure. These fragments of the attack could occur periodically every 20-40 s. We postulate that short NPD attacks are actually epileptic seizures originating from the frontal lobes. The rhythmicity of the episodes may be due to rhythmic oscillation of cortical function during non-REM sleep. 相似文献
58.
Dominici Carlo Nicotra Maria Rita Alemaà Stefano Bosman Cesare Castello Manuel A. Donfrancesco Alberto Gallo Pietro Natali Pier Giorgio 《Journal of neuro-oncology》1997,31(1-2):57-64
In neuroblastoma, high levels of mRNA for p14h
trkA
and p75
LNGFR
neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140
trkA
and ME20.4 anti-p75
LNGFR
mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140
trkA
and in 5 of 28 tumors for p75
LNGFR
. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140
trkA
(p < 0.05) and 71% (20 of 28 cases) for p75
LNGFR
(p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio. 相似文献
59.
Letizia Mazzini Daniela Testa Carla Balzarini Gabriele Mora 《Journal of neurology》1994,241(4):223-227
Based on the hypothesis that free radicals play a general role in the neurodegenerative process in motor neuron disease, we tested selegiline in a group of patients affected by amyotrophic lateral sclerosis (ALS) to examine whether it might modify the progression of the disease. Patients were admitted if they were 25–80 years old and had a confirmed diagnosis of ALS with symptoms lasting no longer than 24 months. Patients with familial ALS, pure progressive bulbar palsy, primary lateral sclerosis or progressive muscle atrophy were excluded; a total of 111 patients were recruited. Fifty-three patients were randomly assigned to receive the drug (selegiline 10 mg/day orally for 6 months) and the remaining 58 were considered ALS controls. Mortality was similar in the two groups (4 and 5 patients respectively), though the difference was not statistically significant. Among the survivors, mean MRC and Norris disability scores and forced vital capacity were fairly similar in the two groups at all times and no statistically significant difference between treated and untreated patients was found. The results did not change when the data were related to age, duration and characteristics of onset of the disease. The rate of progression was significantly more rapid in patients with bulbar symptoms in both groups. Our data do not show any significant effect of selegiline in modifying the progression of ALS. 相似文献
60.
Stefanini ML Colli C Lerner BR Lei DL Chaves SP Di Pietro MS Oliveira AA Szarfarc SC 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》1995,11(3):439-447
The authors studied a sample of students entering the first grade in the Osasco public school system in order to determine both the prevalence of anemia and nutritional status. Osasco is part of the Greater S o Paulo Metropolitan Area. Diagnosis of anemia was made through the hemoglobin concentration of blood from digital puncture. World Health Organization (WHO) levels were used to define anemia. Nutritional Status assessment. was made through weight/age and height/age indices, using Z score distribution and the National Center for Health Statistics (NCHS) reference levels. Prevalence of anemia was 51%. Prevalence levels varied according to the schools' geographic location: 56.9% in peripheral neighborhoods and 41.7% in central areas. Children with illiterate parents had a higher prevalence of this condition. Risk of anemia was higher for children who were over eight years of age when entering the first grade. Acute malnutrition was not found. Prevalence was higher than expected and points to the urgent need to establish an anemia control program for schoolchildren in this population. 相似文献