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51.
S A Chalew R A Lozano K M Armour A A Kowarski 《International journal of obesity (2005)》1992,16(6):459-463
Obesity in childhood is characterized by subnormal integrated concentrations of growth hormone (IC-GH) and elevated integrated concentrations of insulin (IC-I). We tested whether a reduction of IC-I induced by a low calorie diet would lead to a rise of IC-GH into the normal range for age. Six obese children (body mass index (BMI) 39.1 +/- 9.2 kg/m2) underwent integrated concentration (IC) studies by continuous withdrawal before and again 5-8 weeks after being on a low calorie diet. In response to the diet BMI was lower 34.7 +/- 9.4 kg/m2 (P less than 0.003), and IC-I was considerably reduced, 479 +/- 255 pM initially vs. 109 +/- 109 pM on the diet, P less than 0.0008. IC-GH increased modestly from 1.6 +/- 0.6 micrograms/l initially to 2.4 +/- 0.6 micrograms/l, P less than 0.01 on the diet. None of the patients had repeat IC-GH levels which were above the lower limit of normal for lean children of normal stature (3.2 micrograms/l). Single sample insulin-like growth factor 1 (IGF-1) levels were unchanged: 40.9 +/- 23.1 nM initially vs. 49.7 +/- 25.7 nM (314.6 +/- 197.7 vs. 382.5 +/- 217.0 ng/ml, n.s.). Thus reduction of high insulin concentrations during 5-8 weeks of a low calorie diet has only a small effect on IC-GH in obese children. Factors other than circulating insulin levels are likely to play the major role in mediating the reduced levels of GH observed in obesity. 相似文献
52.
J M Pérez Trullen P J Modrego Pardo M Vázquez André J J López Lozano 《Biomedicine & Pharmacotherapy》1992,46(8):375-376
Benzodiazepines are drugs with a good tolerance that are widely used for the treatment of anxiety. Extrapyramidal side-effects are unusual. Diazepam is effective for the treatment of drug-induced dystonias, nevertheless there are some reports of Diazepam-induced dystonia. We report a case history of a patient who developed oromandibular dystonia after taking Bromazepam. The possible mechanisms that cause drug-induced dystonia are described. 相似文献
53.
Robson Frederico Cunha Daniela Maria Carvalho Pugliesi Célio Percinoto 《Dental traumatology》2007,23(6):360-363
This retrospective study examined some different types of treatment to primary teeth. The aim of this study was to assess the treatment of traumatized primary teeth and the importance of a long-term follow up. Brazilian children in the age group of 1-4 years from a baby clinic took part in the study. Three hundred and fifteen patients suffered some type of traumatic injury, a total of 338 affected teeth. Data were registered in specific records and submitted to statistic analysis. The most prevalent type of treatment was monitor only (85%) followed by tooth extraction and endodontic procedure. Invasive treatments were performed in case of severe traumas, usually 6 months after the injury. We verified that a careful follow up might be the preferential choice to the treatment of traumatic primary teeth even in some severe cases. 相似文献
54.
Leonardo A Sechi Giovanna E Felis Niyaz Ahmed Daniela Paccagnini Donatella Usai Silvia Ortu Paola Molicotti Stefania Zanetti 《Infection, genetics and evolution》2007,7(4):424-432
Mycobacterium avium subsp. paratuberculosis (MAP) is the etiological agent of Johne's disease (JD), a chronic gastroenteritis of ruminants and other animals, including primates. Many evidences suggested association of MAP to Crohn's disease, a chronic granulomatous gastrointestinal disease of humans with strong similarities with JD. The present study attempts to evaluate global gene regulation in MAP, which has not been addressed previously, despite the availability of MAP genome sequence. For this purpose, we investigated: (i) the presence of sigma factors and their relationship to sigma factors of other mycobacteria (M. avium subsp.avium, M. tuberculosis, M. bovis, M. leprae and M. smegmatis), and (ii) their expression during different growth conditions and in vitro infection of intestinal epithelial Caco2 cells. MAP genome contains 19 putative sigma factor, but only 12 belong to gene families common to other mycobacteria. Gene expression was evaluated with Real-Time PCR during growth in 7H9 medium and mycobactin J, in 7H9 medium plus mycobactin J and lisozyme, and during infection of Caco2 cells: very different expression patterns were observed and, on the whole, only 7 sigma factors were found to be expressed. sigJ was upregulated during the infection of Caco2 cells. Even if only few sigma factors were expressed in the three conditions tested, the overall high numbers of MAP sigma factors suggests a noteworthy flexibility of this pathogen. Thus, this first report on expression of MAP sigma factors opens the way to an extensive characterization of global gene regulation, as a key to understand strategies of survival and mechanisms of infections used by this organism. 相似文献
55.
Vincenzo De Giorgi MD Daniela Massi MD Elisa Trez MD Camilla Salvini MD Elena Quercioli MD Paolo Carli MD 《Dermatologic surgery》2003,29(9):965-967
In dermoscopy, the correct recognition of the single parameters is fundamental to achieve great diagnostic accuracy, but the scarce morphologic expression of a parameter may lead to diagnostic errors. We report the case of a 27-year-old white man presenting a pigmented lesion of the back, which was present since puberty. Clinical examination revealed on the back the presence of a flat, gray-blue lesion and at the periphery a small dark-brown papule. An assessment of the lesion by means of dermoscopy was performed. The purpose of this report was to analyze the Blue Hue in dermoscopy with its histopathologic correlates, starting with the discussion of a clinical case. 相似文献
56.
Sami Schiff Daniela Mapelli Antonino Vallesi Raffaele Orsato Angelo Gatta Carlo Umiltà Piero Amodio 《Clinical neurophysiology》2006,117(8):1728-1736
OBJECTIVE: This study aims to evaluate the efficiency of top-down and bottom-up processes in the extrastriate cortex of cirrhotic patients without overt hepatic encephalopathy (HE). METHODS: Reaction times (RTs), accuracy and event-related potentials (ERPs) were recorded during the execution of a visual Simon task in 17 cirrhotic patients and 10 healthy controls. Amplitude and latency of the P1 and N1 (indexes of bottom-up processes) and of the N2pc (index of top-down processes) were measured. RESULTS: Patients were slower than controls, and patients with minimal HE (MHE) were slower than patients without MHE. The distribution analysis of RTs showed that the Simon effect decays with slower RTs in all the groups and that the shape of the distribution was different in MHE patients. No differences were found between cirrhotic patients and controls for P1 and N1 amplitude and latency. In contrast, N2pc latency was delayed in cirrhotic patients compared to controls independently of MHE. CONCLUSIONS: In the extrastriate cortex of cirrhotic patients without HE, top-down processes are altered whereas bottom-up processes are preserved. SIGNIFICANCE: The analysis of exogenous and endogenous visual components of ERPs provides a model to study the functional dissociation between top-down and bottom-up processes inside the extrastriate cortex. 相似文献
57.
58.
Deletion of the Major Proteolytic Site of the Helicobacter pylori Cytotoxin Does Not Influence Toxin Activity but Favors Assembly of the Toxin into Hexameric Structures 总被引:1,自引:0,他引:1
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Daniela Burroni Pietro Lupetti Cristina Pagliaccia Jean Marc Reyrat Romano Dallai Rino Rappuoli John L. Telford 《Infection and immunity》1998,66(11):5547-5550
The Helicobacter pylori cytotoxin is proteolytically cleaved at a flexible hydrophilic loop into two subunits. Deletion of the loop sequences had no effect on biological activity of the toxin in the HeLa cell vacuolation assay but favored the organization of the protein into hexameric rather than heptameric structures. 相似文献
59.
M Ahumada Ayala D Lozano O Lozano J A Rull M Cárdenas V Valles B Wong 《Archivos del Instituto de Cardiología de México》1988,58(1):15-26
Several lines of evidence have clearly established the role of lipoproteins as risk factors for the development of atherosclerosis. Epidemiologic studies from different countries have found that about one third of myocardial infarction survivors under 60 years of age are hyperlipidemic. The acute stress reaction occurring in the first hours following an acute myocardial infarction causes distinct changes in the patient's metabolic profile, these changes include a significant reduction of total cholesterol and cholesterol associated with low density lipoproteins and a usually mild elevation of blood glucose. With the purpose of establishing the prevalence and severity of lipoprotein disorders found in myocardial infarction survivors living in Mexico city we conducted a prospective study of 106 consecutive admissions to the coronary care unit at the National Institute of Cardiology with the fully proven diagnosis of acute myocardial infarction, we included only patients younger than 60 years of age that could be sampled within the first 72 hours of the appearance of typical symptoms, at this time the coronary risk factor profile was assessed and blood samples were drawn (acute sample). After three months of the diagnosis we sampled 81 of the original 106 patients (chronic sample). The comparison of these 81 patients showed remarkable differences in the lipid values obtained on each sample. The mean value for total cholesterol in the acute sample was 225 mg/dl whereas the corresponding value for the chronic sample was 240.5 mg/dl (p less than 0.005). This difference was also highly significant for the low density fraction. On the basis of the chronic sample analysis we estimated a prevalence of hyperlipoproteinemia of 35.8%. (II: 18.5%, III: 2.5%, IV: 14.8%), an additional subgroup of 10 patients (12.3%) had the hypo-HDL phenotype raising the number of subjects at risk for atherosclerosis to as high as 48.1% considering only the lipoproteins. The prevalence figures for the rest of the risk factors were as follows: 70.3% for tobacco smoking, 35.8% for Systemic Arterial Hypertension, 33.4% for Obesity and 30.8% for Diabetes Mellitus. Among the group of 81 patients, 17 were known diabetics, eight additional cases of Diabetes Mellitus were diagnosed at the chronic phase (two with fasting hyperglycemia and six with diagnostic oral glucose tolerance tests). The "acute plase" glycemia for these eight subjects was significantly higher (mean: 98.4 mg/dl) than the corresponding value for the non diabetic patients (mean: 83.4 mg/dl p less than 0.002), the seventeen known diabetics had a mean glycemia of 150.6 mg/dl in the acute sample.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
60.
Inflammatory regulation of extracellular matrix remodeling in calcific aortic valve stenosis. 总被引:11,自引:0,他引:11
Jens J Kaden Carl-Erik Dempfle Rainer Grobholz Carolin S Fischer Daniela C Vocke Refika Kili? Aslihan Sariko? Rafael Pi?ol Siegfried Hagl Siegfried Lang Martina Brueckmann Martin Borggrefe 《Cardiovascular pathology》2005,14(2):80-87
BACKGROUND: Calcific aortic stenosis (AS), the most frequent heart valve disorder in developed countries, leads to the calcification and fibrous thickening of the valve. While several studies have addressed the process of valvular calcification, the molecular pathomechanisms of the extensive matrix remodeling remain unclear. Because inflammation is present in stenotic valves, we hypothesized that the proinflammatory cytokine tumor necrosis factor alpha (TNFalpha) might influence cell proliferation and regulate the expression and activation of matrix metalloproteinases (MMPs)--enzymes that are thought to be involved in calcific AS. METHODS: Immunohistochemistry for leukocytes, TNFalpha, MMP-1, and the endogenous MMP inhibitor tissue inhibitor of metalloproteinase (TIMP)-1 was performed on human stenotic (n = 19) and control (n = 8) valves. Primary cultures of human aortic valve myofibroblasts were incubated with and without TNFalpha, and cell proliferation was assessed. The expression and activation of MMP-1 were detected by Western blotting and a specific MMP-1 activity assay. RESULTS: Control valves showed scattered macrophages and low expression of TNFalpha, MMP-1, and TIMP-1. In stenotic valves, leukocyte infiltration and a strong, colocalized expression of TNFalpha and MMP-1 were present, while TIMP-1 remained unchanged. Double-label immunofluorescence localized TNFalpha mainly to macrophages. In cultured human aortic valve myofibroblasts, TNFalpha stimulated proliferation and induced a time-dependent increase in MMP-1 expression and activation, while TIMP-1 remained unchanged. CONCLUSION: The results indicate that matrix remodeling in calcific AS involves the expression and activation of MMPs. Activated leukocytes, by the secretion of TNFalpha, may stimulate valvular myofibroblasts to proliferate and express MMPs, thus regulating actively the matrix remodeling in calcific AS. 相似文献