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91.
Ricardo Tedeschi Matos Rodrigo Schuler Honório Elia Garcia Caldini Claudio Lyoiti Hashimoto Marcelo Alves Ferreira Tomás Navarro-Rodriguez 《Clinics (S?o Paulo, Brazil)》2009,64(7):669-674
ABSTRACT:
The purpose of this study was to compare esophageal infusion with 0.1 N hydrochloridric acid (HCl) to esophageal infusion with saline in patients presenting with typical gastroesophageal reflux symptoms and erosive esophagitis.METHODS:
Upper gastrointestinal endoscopy was performed on 44 prospective subjects, 29 of whom were included in the study. Eighteen patients presented with normal esophagi (Control Group “C”), nine of whom were infused with HCl and nine with saline. Eleven patients presented with erosive esophagitis (Lesion Group “L”), five of whom were infused with HCl and six with saline. Biopsies of the esophageal mucosa were collected before and after infusions.RESULTS:
No statistically significant difference was found between the two types of infusions in terms of the dilation of the intercellular space of the esophageal epithelium, regardless of the status of the patient.CONCLUSIONS:
Response to HCl infusion cannot be used as a marker for gastroesophageal reflux disease. 相似文献92.
Missense FGFR3 mutations create cysteine residues in thanatophoric dwarfism type I (TD1) 总被引:10,自引:1,他引:10
Rousseau F; el Ghouzzi V; Delezoide AL; Legeai-Mallet L; Le Merrer M; Munnich A; Bonaventure J 《Human molecular genetics》1996,5(4):509-512
Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with
micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced
thoracic cavity. In the most common subtype (TD1), femurs are curved, while
in TD2, straight femurs are associated with cloverleaf skull. Mutations in
the fibroblast growth factor receptor 3 (FGFR3) gene were identified in
both subtypes. While TD2 was accounted for by a single recurrent mutation
in the tyrosine kinase 2 domain, TD1 resulted from either stop codon
mutations or missense mutations in the extracellular domain of the gene.
Here, we report the identification of FGFR3 mutations in 25/26 TD cases.
Two novel missense mutations (Y373C and G370C) were detected in 8/26 and
1/26 TD1 cases respectively. Both mutations created cysteine residues in
the juxta extramembrane domain of the receptor. Sixteen cases carried the
previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon
FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically
homogeneous condition and give additional support to the view that newly
created cysteine residues in the extracellular domain of the protein play a
key role in the severity of the disease.
相似文献
93.
Ruiz A Guedes AC Muñoz MC Molina JM Hermosilla C Martín S Hernández YI Hernández A Pérez D Matos L López AM Taubert A 《Parasitology research》2012,110(6):2131-2136
Coccidiosis is probably the main parasitic disease affecting goat kids around the weaning period, leading to high economic losses in goat production due to deaths and delayed growth rates of infected animals. A total of 101 kids of 2-4 weeks of age, naturally infected with Eimeria spp., were divided into five groups and studies were conducted to analyse the effects of metaphylactic administration of diclazuril (Vecoxan?) on parasitological and productive parameters. Two different doses of diclazuril (1 and 2 mg/kg BW, p.o.) were given either at 3 weeks (single treatment) or at 3 and 5 weeks of life (double treatment). The faecal oocyst shedding and the body weights of the animals were monitored at 2-weeks intervals for 6 consecutive weeks. Treatments of goat kids with diclazuril were effective against the three most predominant Eimeria species recorded in this study (E. arloingi, E. ninakohlyakimovae and E. christenseni) and also against other minor species found in faecal examinations, including E. alijevi, E. caprina, E. jolchijevi, E. caprovina, E. hirci and E. aspheronica). In consequence, OPG values lower than 1?×?10(3) were detected in 90 to 100% of the animals up to 15-20 days post-treatment depending on the treatment regimen. Even a single dose of 1 mg/kg BW p.o. resulted in an increase of growth rates in treated animals and therefore should be considered as a control strategy in farms precluding coccidian infections, whilst double and multiple dose treatments could be the recommendation for environments heavily contaminated with Eimeria oocysts. In relation to the OPG reduction and increased growth rates, the severity of the clinical signs (i.e., diarrhoea) was ameliorated in treated animals during the course of infection compared to that of non-treated or control kids. The precise timing of treatment appears crucial in order to prevent severe clinical coccidiosis and thereby enabling the adequate development of protective immune response against Eimeria challenge infections. 相似文献
94.
Low-Intensity physical activity beneficially alters the ultrastructural renal morphology of spontaneously hypertensive rats 总被引:1,自引:0,他引:1
Garcia-Pinto AB de Matos VS Rocha V Moraes-Teixeira J Carvalho JJ 《Clinics (S?o Paulo, Brazil)》2011,66(5):855-863
INTRODUCTION AND OBJECTIVE:
Kidney disorders can cause essential hypertension, which can subsequently cause renal disease. High blood pressure is also common among those with chronic kidney disease; moreover, it is a well-known risk factor for a more rapid progression to kidney failure. Because hypertension and kidney function are closely linked, the present study aimed to observe the beneficial effects of low-intensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats.METHOD:
Male Wistar-Kyoto rats and spontaneously hypertensive rats were randomly allocated into four groups: sedentary or exercised Wistar-Kyoto and sedentary or exercised spontaneously hypertensive rats. The exercise lasted 20 weeks and consisted of treadmill training for 1 hour/day, 5 days/week.RESULTS:
The exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26%. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity: (i) the interdigitations of the proximal and distal convoluted tubules; (ii) the basal membrane of the proximal and distal convoluted tubules; and (iii) in the basal membrane, slit diaphragm and pedicels of the glomerular filtration barrier. The spontaneously hypertensive rats also showed a decreased expression of connexin-43.CONCLUSION:
Physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals. 相似文献95.
KJ Champion C Bunag AL Estep JR Jones CH Bolt RC Rogers KA Rauen DB Everman 《Clinical genetics》2011,79(5):468-474
Champion KJ, Bunag C, Estep AL, Jones JR, Bolt CH, Rogers RC, Rauen KA, Everman DB. Germline mutation in BRAF codon 600 is compatible with human development: de novo p.V600G mutation identified in a patient with CFC syndrome. BRAF, the protein product of BRAF, is a serine/threonine protein kinase and one of the direct downstream effectors of Ras. Somatic mutations in BRAF occur in numerous human cancers, whereas germline BRAF mutations cause cardio‐facio‐cutaneous (CFC) syndrome. One recurrent somatic mutation, p.V600E, is frequently found in several tumor types, such as melanoma, papillary thyroid carcinoma, colon cancer, and ovarian cancer. However, a germline mutation affecting codon 600 has never been described. Here, we present a patient with CFC syndrome and a de novo germline mutation involving codon 600 of BRAF, thus providing the first evidence that a pathogenic germline mutation involving this critical codon is not only compatible with development but can also cause the CFC phenotype. In vitro functional analysis shows that this mutation, which replaces a valine with a glycine at codon 600 (p.V600G), leads to increased ERK and ELK phosphorylation compared to wild‐type BRAF but is less strongly activating than the cancer‐associated p.V600E mutation. 相似文献
96.
H4 acetylation, XIST RNA and replication timing are coincident and define x;autosome boundaries in two abnormal X chromosomes 总被引:2,自引:1,他引:2
The inactive X (Xi) differs from its active homologue (Xa) in a number of
ways, including increased methylation of CpG islands, replication late in S
phase, underacetylation of histone H4 and association with XIST RNA. Global
changes in DNA methylation occur relatively late in development, but the
other properties all change during or shortly after the establishment of Xi
and may play a role in the mechanism by which an inactive chromatin
conformation spreads across most of the chromosome. In the present report,
we use two human X;autosome translocation chromosomes to study the
spreading of inactive X chromatin across X;autosome boundaries. In one of
these chromosomes, t(X;6), Xp distal to p11.2 is replaced by 6p21.1-6pter
and, in the other, ins(X;16), a small fragment derived from 16p13 is
inserted into the distal third of Xq. In lymphoid cells from patients
carrying these translocations in an unbalanced form, Xi was shown by HUMARA
assay to be derived exclusively [t(X:6)] or predominantly [ins (X;16)] from
the derived X chromosome. We used a combination of immunolabelling and
RNA/DNA fluorescence in situ hybridization to define the distribution of
XIST RNA, deacetylated H4 and late-replicating DNA across the two derived X
chromosomes in inactive form. Within the limits of the cytogenetic
techniques employed, the results show complete coincidence of these three
parameters, with all three being excluded from the autosomal component of
the derived X chromosome.
相似文献
97.
Matos JE Sorensen MV Geyti CS Robaye B Boeynaems JM Leipziger J 《Pflügers Archiv : European journal of physiology》2007,454(6):977-987
Luminal P2 receptors are ubiquitously expressed in transporting epithelia. In steroid-sensitive epithelia (e.g., lung, distal
nephron) epithelial Na+ channel (ENaC)-mediated Na+ absorption is inhibited via luminal P2 receptors. In distal mouse colon, we have identified that both, a luminal P2Y2 and a luminal P2Y4 receptor, stimulate K+ secretion. In this study, we investigate the effect of luminal adenosine triphosphate/uridine triphosphate (ATP/UTP) on electrogenic
Na+ absorption in distal colonic mucosa of mice treated on a low Na+ diet for more than 2 weeks. Transepithelial electrical parameters were recorded in an Ussing chamber. Baseline parameters:
transepithelial voltage (V
te): −13.7 ± 1.9 mV (lumen negative), transepithelial resistance (R
te): 24.1 ± 1.8 Ω cm2, equivalent short circuit current (I
sc): −563.9 ± 63.8 μA/cm2 (n = 21). Amiloride completely inhibited I
sc to −0.5 ± 8.5 μA/cm2. Luminal ATP induced a slowly on-setting and persistent inhibition of the amiloride-sensitive I
sc by 160.7 ± 29.7 μA/cm2 (n = 12, NMRI mice). Luminal ATP and UTP were almost equipotent with IC50 values of 10 μM and 3 μM respectively. In P2Y2 knock-out (KO) mice, the effect of luminal UTP on amiloride-sensitve Na+ absorption was absent. In contrast, in P2Y4 KO mice the inhibitory effect of luminal UTP on Na+ absorption remained present. Semiquantitative polymerase chain reaction did not indicate regulation of the P2Y receptors
under low Na+ diet, but it revealed a pronounced axial expression of both receptors with highest abundance in surface epithelia. Thus,
luminal P2Y2 and P2Y4 receptors and ENaC channels co-localize in surface epithelium. Intriguingly, only the stimulation of the P2Y2 receptor mediates inhibition of electrogenic Na+ absorption. 相似文献
98.
Amanda Karolina Soares e Silva Dilênia de Oliveira Cipriano Torres Sura Wanessa Santos Rocha Fabiana Oliveira dos Santos Gomes Bruna dos Santos Silva Mariana Aragão Matos Donato Catarina Raposo Ana Célia Oliveira Santos Maria do Carmo Alves de Lima Suely Lins Galdino Ivan da Rocha Pitta José Roberto Botelho de Souza Christina Alves Peixoto 《Cardiovascular pathology》2013,22(1):81-90
BackgroundAtherosclerotic cardiovascular disease is a chronic inflammatory condition. Thiazolidinediones (TZDs) are used to enhance sensitivity to insulin and have demonstrated a protective effect over a variety of cardiovascular markers and risk factors. Controversially, the TZDs are associated with the development of heart failure. Thus, lines of research have invested in the search for new molecules in order to obtain more selective and less harmful treatment alternatives for the pathogenesis of atherosclerosis and its risk factors.MethodsAnimals were fed a diet rich in fat for 10 weeks. In the last 2 weeks, animals received either pioglitazone, LPSF/GQ-02, or LPSF/GQ-16 daily through gavage. At the end of the treatment, blood was collected for biochemical analysis and the aortas were dissected for subsequent analyses.ResultsNo changes in the blood lipid profile were found following the use of the drugs in comparison to the control. However, the new thiazolidine derivatives were more efficient in improving insulin resistance in comparison to pioglitazone and the control group. Morphometric analyses revealed that neither pioglitazone nor LPSF/GQ16 led to satisfactory effects over atherosclerosis. However, LPSF/GQ-02 led to a reduction in area of the atherosclerotic lesions. Ultrastructural analyses revealed extensive degeneration of the endothelium and an increase in apoptotic cells in the subendothelial space following the use of pioglitazone and LPSF/GQ-16. However, LPSF/GQ-02 caused minimal cell alterations in the aortic endothelium. Regarding markers, endothelial nitric oxide synthase (eNOS) and matrix metalloproteinase 9 (MMP-9), LPSF/GQ-16, and pioglitazone exerted similar effects, increasing the expression of MMP-9, and had no effect on the expression of eNOS compared with the control group. On the other hand, LPSF/GQ-02 was effective in reducing the expression of MMP-9 and increased eNOS significantly.ConclusionsThe results suggest that the new thiazolidine derivative LPSF/GQ-02 is a promising candidate for the treatment of atherosclerosis. 相似文献
99.
Eduardo D. E. Papa Izo Helber Manes R. Ehrlichmann Claudia Maria Rodrigues Alves Marcia Makdisse Livia N. Matos Jairo Lins Borges Renato D. Lopes Edson Stefanini Antonio Carlos Carvalho 《Clinics (S?o Paulo, Brazil)》2013,68(12):1481-1487
OBJECTIVES:
To correlate the importance of the ankle-brachial index in terms of cardiovascular morbimortality and the extent of coronary arterial disease amongst elderly patients without clinical manifestations of lower limb peripheral arterial disease.METHODS:
We analyzed prospective data from 100 patients over 65 years of age with coronary arterial disease, as confirmed by coronary angiography, and with over 70% stenosis of at least one sub-epicardial coronary artery. We measured the ankle-brachial index immediately after coronary angiography, and a value of <0.9 was used to diagnose peripheral arterial disease.RESULTS:
The patients'' average age was 77.4 years. The most prevalent risk factor was hypertension (96%), and the median late follow-up appointment was 28.9 months. The ankle-brachial index was <0.9 in 47% of the patients, and a low index was more prevalent in patients with multiarterial coronary disease compared to patients with uniarterial disease in the same group. Using a bivariate analysis, only an ankle-brachial index of <0.9 was a strong predictive factor for cardiovascular events, thereby increasing all-cause deaths and fatal and non-fatal acute myocardial infarctions two- to three-fold.CONCLUSION:
In elderly patients with documented coronary disease, a low ankle-brachial index (<0.9) was associated with the severity and extent of coronary arterial disease, and in late follow-up appointments, a low index was correlated with an increase in the occurrence of major cardiovascular events. 相似文献100.
Janneke AL van Kempen Henk J Schers Anne Jacobs Sytse U Zuidema Franca Ruikes Sarah HM Robben René JF Melis Marcel GM Olde Rikkert 《The British journal of general practice》2013,63(608):e225-e231