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101.
Gian Marco Moneta Claudia Bracaglia Ivan Caiello Chiara Farroni Denise Pires Marafon Raffella Carlomagno Linda Hiraki Marina Vivarelli Alessandra Gianviti Simone Carbogno Walter Ferlin Cristina de Min Earl Silverman Rita Carsetti Fabrizio De Benedetti Emiliano Marasco 《European journal of immunology》2023,53(7):2250319
102.
Chiara Mazziotta Carmen Lanzillotti Marcello Govoni Simonetta Falzoni Maria Letizia Tramarin Elisa Mazzoni Mauro Tognon Fernanda Martini John Charles Rotondo 《Immunology》2023,168(4):671-683
Oncogenic Merkel cell polyomavirus (MCPyV) provokes a widespread and asymptomatic infection in humans. Herein, sera from healthy children and young adults (HC, n = 344) aged 0–20 years old were evaluated for anti-MCPyV immunoglobulin G (IgG) and IgM antibodies employing a recently developed immunoassay. Serum MCPyV IgG data from healthy subjects (HS, n = 510) and elderlies (ES, n = 226), aged 21–65/66–100 years old, from our previous studies, were included. The anti-MCPyV IgG and IgM rates in HC sera were 40.7% and 29.7%, respectively. A lower prevalence of anti-MCPyV IgGs was found in HC aged 0–5 years old (13%) compared to 6–10 (52.3%), 11–15 (60.5%) and 16–20 years old (61.6%) cohorts. Age-stratified HCs exhibited similar anti-MCPyV IgM rates (27.9%–32.9%). Serological profiles indicated that anti-MCPyV IgGs and IgMs had low optical densities (ODs) during the first years of life, while IgM ODs appeared to decrease throughout young adulthood. A lower anti-MCPyV IgGs rate was found in HC (40.7%) than HS (61.8%) and ES (63.7%). Upon the 5-years range age-stratification, a lower anti-MCPyV IgGs rate was found in the younger HC cohort aged 0–5 years old compared to the remaining older HC/HS/ES cohorts (52.3%–72%). The younger HC cohort exhibited the lowest anti-MCPyV IgG ODs than the older cohorts. Low anti-MCPyV IgMs rates and ODs were found in the 21–25 (17.5%) and 26–30 (7.7%) years old cohorts. Our data indicate that, upon an early-in-life seroconversion, the seropositivity for oncogenic MCPyV peaks in late childhood/young adulthood and remains at high prevalence and relatively stable throughout life. 相似文献
103.
104.
Nongastrointestinal mucosa-associated lymphoid tissue (MALT) lymphomas: Clinical and therapeutic features of 24 localized patients 总被引:1,自引:0,他引:1
P. L. Zinzani M. Magagnoli S. Ascani P. Ricci V. Poletti F. Gherlinzoni G. Frezza M. Bendandi C. Stefanetti E. Merla S. Pileri S. Tura 《Annals of oncology》1997,8(9):883-886
Background: Peripheral B-cell lymphoma of the marginal zone (MALT, low-grade), presenting as localized, extranodal disease, usually affects the elderly. The gastrointestinal tract is the most frequently involved extranodal location, representing 70% of all MALT lymphomas. Recently, numerous other extranodal sites involved by MALT lymphomas have also been described.Patients and methods: From January 1990 to October 1995, 24 patients with untreated nongastrointestinal low-grade MALT lymphoma were submitted to treatments ranging from the local approach of radiotherapy and local -interferon (-IFN) administration to chemotherapy. The tumours were located in the lung (seven cases), conjunctiva (four cases), lachrymal gland and orbital soft tissue (four cases), salivary glands (three cases), skin (three cases), breast (two cases)' and thyroid (one case). All patients had low-grade stage IE tumours.Results: Chemotherapy was administered in 11 patients (six with lung, three with salivary gland, one with breast, and one with thyroid locations); radiation therapy was employed in seven patients (three with lachrymal gland, three with skin, and one with breast locations); local -IFN administration was administered in five patients (four with conjunctival, and one with lachrymal gland sites); and surgery was employed in one patient with a lung tumour. All patients achieved complete remissions; three local recurrences and two relapses in other sites were observed. The global five-year survival rate was 100% with a relapse-free survival rate of 79%.Conclusions: These data confirm the significant efficacy of different therapeutic approaches to specific sites inbes obtaining a good remission rate for nongastrointestinal localized low-grade MALT lymphomas. 相似文献
105.
Pacini Laura Limatola Cristina De Laurenzi Vincenzo Ricci Irene Spinedi Angelo 《Journal of neuro-oncology》1997,31(1-2):141-146
In the human neuroblastoma cell line SK-N-BE(2), arachidonic acid (AA), supplied in the medium at micromolar concentrations, markedly ehnanced [14C]stearic acid (SA) (but not [14C]palmitic acid or [14C]oleic acid) incorporation into phosphatidylinositol (PtdIns). AA failed to stimulate [14C]SA incorporation into PtdIns precursors, namely phosphatidic acid and cytidinediphosphodiacylglycerol; furthermore, enhanced [14C]SA incorporation, brought about by exogenously administered AA, was not restricted to PtdIns tetraenoic species. When cells were pulsed for 1 h with [14C]SA (either in the presence or absence of AA) and then reincubated in AA- and [14C]SA-free medium, a marked loss of radioactivity from PtdIns was observed, that however was restricted to molecular species other than tetraenoic. These results are discussed in the light of possible mechanisms through which PtdIns achieves the 1-stearoyl-2-arachidonoyl configuration. 相似文献
106.
Angela Bachi Raffaella Brambilla Roberto Fanelli Roberto Bianchi Ettore Zuccato Chiara Chiabrando 《British journal of pharmacology》1997,121(8):1770-1774
- 8-epi-prostaglandin (PG) F2α, a major F2 isoprostane, is produced in vivo by free radical-dependent peroxidation of lipid-esterified arachidonic acid. Both cyclo-oxygenase isoforms (COX-1 and COX-2) may also form free 8-epi-PGF2α as a minor product. It has been recently seen in human volunteers that the overall basal formation of 8-epi-PGF2α in vivo is mostly COX-independent and urinary 8-epi-PGF2α is therefore an accurate marker of ‘basal'' oxidative stress in vivo.
- To test the validity of this marker in the rat, we evaluated in vivo the effect of COX inhibition on the formation of 8-epi-PGF2α vs prostanoids. Two structurally unrelated COX inhibitors (naproxen: 30 mg kg−1 day−1; indomethacin: 4 mg kg−1 day−1) were given i.p. to rats kept in metabolic cages. In vivo formation of 8-epi-PGF2α was assessed by measuring its urinary excretion. Prostanoid biosynthesis was assessed by measuring urinary excretion of major metabolites of thromboxane (TX) and prostacyclin (2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF1α). All compounds were selectively measured by immunopurification/gas chromatography-mass spectrometry.
- Naproxen reduced urinary excretion of 2,3-dinor-TXB1 and 2,3-dinor-6-keto-PGF1α but, unexpectedly, also that of 8-epi-PGF2α (82, 49 and 52% inhibition, respectively). Indomethacin had a similar effect (77, 69 and 55% inhibition). Esterified 8-epi-PGF2α in liver and plasma remained unchanged after indomethacin.
- These findings prompted us to re-assess the contribution of COX activity to the systemic production of 8-epi-PGF2α in man. We gave naproxen (1 g day−1) to healthy subjects (four nonsmokers and four smokers). Urinary 8-epi-PGF2α remained unchanged in the two groups (9.63±0.99 before vs 10.24±1.01 after and 20.14±3.00 vs 19.03±2.45 ng h−1 1.73 m−2), whereas there was a marked reduction of major urinary metabolites of thromboxane and prostacyclin (about 90% for both 11-dehydro-TXB2 and 2,3-dinor-TXB2; >50% for 2,3-dinor-6-keto-PGF1α).
- To investigate whether rat COX-1 produces 8-epi-PGF2α more efficiently than human COX-1, we measured the ex vivo formation of 8-epi-PGF2α and TXB2 simultaneously in whole clotting blood. Serum levels of 8-epi-PGF2α and TXB2 were similar in rats and man.
- We conclude that a significant amount of COX-dependent 8-epi-PGF2α is present in rat but not in human urine under normal conditions. This implies that urinary 8-epi-PGF2α cannot be used as an index of near-basal oxidant stress in rats. On the other hand, our data further confirm the validity of this marker in man.
107.
Carlo Centemeri Chiara Bolego Maria P Abbracchio Flaminio Cattabeni Lina Puglisi Geoffrey Burnstock Simonetta Nicosia 《British journal of pharmacology》1997,121(8):1700-1706
- This study was aimed at characterizing ATP-induced rises in cytosolic free calcium ion, [Ca2+]i, in a population of rat striatal astrocytes loaded with the fluorescent Ca2+ probe Fura2, by means of fluorescence spectrometry.
- ATP triggered a fast and transient elevation of [Ca2+]i in a concentration-dependent manner. The responses of the purine analogues 2-methylthio-ATP (2-meSATP), adenosine-5′-O-(2-thiodiphosphate) (ADPβS), as well as uridine-5′-triphosphate (UTP) resembled that of ATP, while α,β-methylene-ATP (α,β-meATP) and β,γ-methylene-ATP (β,γ-meATP) were totally ineffective.
- Suramin (50 μM) had only a minor effect on the ATP response, whereas pyridoxal phosphate-6-azophenyl-2′,4′-disulphonic acid (PPADS) (5 μM) significantly depressed the maximum response.
- Extracellular Ca2+ did not contribute to the observed [Ca2+]i rise: removing calcium from the extracellular medium (with 1 mM EGTA) or blocking its influx by means of either Ni2+ (1 mM) or Mn2+ (1 mM) did not modify the nucleotide responses.
- Furthermore, after preincubation with 10 μM thapsigargin, the nucleotide-evoked [Ca2+]i increments were completely abolished. In contrast, 10 mM caffeine did not affect the responses, suggesting that thapsigargin-, but not caffeine/ryanodine-sensitive stores are involved.
- Both application of the G-protein blocker guanosine-5′-O-(2-thiodiphosphate) (GDPβS) (1 mM) and preincubation with pertussis toxin (PTx) (350 ng ml−1) partially inhibited the nucleotide-mediated responses. Moreover, the phospholipase C (PLC) inhibitor U-73122, but not its inactive stereoisomer U-73343 (5 μM), significantly reduced the ATP-evoked [Ca2+]i rise.
- In conclusion, our results suggest that, in rat striatal astrocytes, ATP-elicited elevation of [Ca2+]i is due solely to release from intracellular stores and is mediated by a G-protein-linked P2Y receptor, partially sensitive to PTx and coupled to PLC.
108.
M. Sabatelli T. Mignogna G. Lippi S. Servidei G. Manfredi E. Ricci E. Bertini M. Lo Monaco P. Tonali 《Acta neuropathologica》1994,87(4):337-342
We studied three patients from two kinships, affected by early onset hereditary motor and sensory neuropathy with probable autosomal recessive inheritance (HMSN type III). Morphological studies of sural nerve biopsies revealed an abnormal myelin proliferation. Two adult patients with long-term follow up, lost ability to walk at 28 and 22 years and showed severe involvement of the cranial nerves. Our observations suggest that hypermyelination neuropathy with early onset is a progressive disease with poor long-term prognosis. In one kinship the occurrence of the disease in two sibs of both sexes but not in parents, is consistent with an autosomal recessive inheritance. Familial cases of hypermyelination neuropathy have not been described in previous reports. Morphological aspects of this condition are compared with other forms of hypermyelination neuropathy.Supported by Telethon-Italy for the project: Chronic inflammatory polyradiculoneuropathy: electrophysiological and immunopathological studies 相似文献
109.
Yuta Kobayashi Alberto Ricci Isidoro Rossodivita Francesco Amenta 《Naunyn-Schmiedeberg's archives of pharmacology》1994,349(6):559-564
In the present study, the pharmacological characteristics and the anatomical localization of dopamine D2-like receptor sites in the extraparenchymal and in the intraparenchymal portion of the rabbit pulmonary artery were investigated using combined radioligand binding and light microscope autoradiography with [3H]-spiroperidol (spiperone) as a ligand. The ligand was bound to sections of the pulmonary artery in a manner consistent with the labelling of dopamine D2-like receptors with an equilibrium dissociation constant (K
d) of about 2.4±0.07 nmol/l and a maximum density of binding sites of 65±4.5 fmol/mg tissue. In contrast, binding experiments made with sections of rabbit lung did not allow the evaluation of specific binding. Light microscope autoradiography showed the development of specific silver grains within the tunica adventitia of extraparenchymal branches of rabbit pulmonary artery and of large and, to a lesser extent, of medium-sized intraparenchymal branches of the pulmonary artery. No silver grains were found within small branches of the pulmonary artery or of the pulmonary vein. Development of adventitial silver grains was inhibited by compounds active at dopamine receptors. The greater sensitivity to displacement by domperidone, haloperidol, (–)-sulpiride and bromocriptine than to displacement byN-propyl-norapomorphine, quinpirole or clozapine suggests that the [3H]-spiroperidol binding sites observed in extraparenchymal, large and medium-sized branches of the pulmonary artery belong, probably, to the dopamine D2 receptor subtype. The possible pre-junctional localization of these sites is discussed.
Correspondence to: R Amenta 相似文献
110.
O Soldati G Caini T Taddei D Colombini M G Ricci O Menoni N Battevi 《La Medicina del lavoro》1999,90(2):244-255
A total of 306 employees of the hospitals of the Leno/Manerbio health area underwent clinical and anamnestic examination in order to ascertain the existence of degenerative diseases of the spine associated with "manual handling of loads" risk. The prevalences obtained for positive anamnestic threshold concerning the lumbosacral spine, the trend of total acute low back pain and of low back pain in the last year showed lower values compared to the entire national group and in any case lower or only slightly above the values for the reference group of non-exposed subjects. Therefore, in order to assess the real prevalences of disorders due to incorrect load handling in hospital environments, it is important to assess the presence of associated disorders of the spine also and especially in outpatients departments. In fact, unsuitable or unfit staff had recently been transferred from the wards to outpatients departments. 56 workers from outpatients departments underwent physical-anamnestic examination: 16 workers (4.5% of the entire group under study) from average-to-high risk wards were identified as suffering from degenerative disorders of the lumbosacral spine. Therefore the prevalence of unfit subjects from hospital wards, cancelling the effect of the turnover factor on outpatients departments, led to an almost twofold total frequency, which rose from 6.9% to 11.4%. 相似文献