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91.
D. G. Kim C.-Y. Kim S. H. Paek D. S. Lee J.-K. Chung H.-W. Jung B.-K. Cho 《Acta neurochirurgica》1998,140(7):665-674
Summary
Background To determine its roles in the diagnosis and the systemic evaluation of metastatic brain tumours, whole-body positron emission
tomography (PET) using [18F]FDG was performed in 20 consecutive patients.
Methods
All patients were thought to be suffering or needing to be differentiated from metastatic brain tumours. Nine patients had
multiple brain lesions; six were older and showed a rim-enhancing lesion with surrounding oedema; seven had homogeneously
enhancing periventricular lesion(s) on computed tomography (CT) and/or magnetic resonance (MR) imaging, thought to be central
nervous system lymphomas. Two patients had skull mass(es) and two patients had a solid mass suspected to be, respectively,
a haemorrhagic metastasis and a metastatic malignant melanoma. All of them received whole-body [18F]FDG PET and conventional systemic work-up for metastasis in order to compare the results of the two methods.
Results
Metastatic brain tumours were diagnosed on whole-body [18F]FDG PET in eleven patients who had extracranial and intracranial hypermetabolic lesions. In nine of these, a conventional
work-up also detected primary lesions which on whole-body [18F]FDG PET were seen to be hypermetabolic foci. Systemic lymph node metastases were detected by whole-body [18F]FDG PET only in two patients and histological diagnosis was possible by biopsy of lymph nodes rather than of brain lesions.
In the remaining nine patients who had only intracranial hypermetabolic foci, histological diagnosis was made by craniotomy
or stereotactic biopsy. It was confirmed that seven of nine patients were suffering from a primary brain tumour and two from
metastatic carcinoma. None of the nine showed evidence of systemic cancer on conventional work-up. Histological diagnoses
of the primary brain tumours were four cases of primary central nervous system lymphoma and one each of multifocal glioblastoma,
Ewing's sarcoma, and cavernous angioma.
Patients felt no discomfort during the whole-body [18F]FDG PET procedure and there were no complications. The false negative rate in [18F]FDG PET and in conventional work-up was 15.4% and 30.7% respectively. There were no false positives on either [18F]FDG PET or conventional work-up.
Conclusion
It is suggested that whole-body [18F]FDG PET is a safe, reliable, and convenient method for the diagnosis and systemic evaluation of patients thought to be suffering
or needing to be differentiated from a metastatic brain tumour. 相似文献
92.
Ngai Suk Wai; Tang Oi Shan; Lao Terence; Ho Pak Chung; Ma Ho Kei 《Human reproduction (Oxford, England)》1995,10(5):1220-1222
Intravaginal misoprostol has been shown to be effective forcervical priming before a surgically induced abortion. The objectivewas to investigate the effectiveness of oral misoprostol incervical dilatation prior to vacuum aspiration between the 6thand 12th weeks of pregnancy. The results showed that in nulliparouspatients, the median cervical dilatation in the treatment group(7.8 mm) was significantly greater than that in the placebogroup (3.7 mm). In multiparous patients, the difference wasalso statistically significant (9.8 versus 6.0 mm). The easeof dilatation, assessed subjectively by the operating surgeons,was significantly improved in the treatment group. There wasalso a significant reduction in the duration of the operationand in the mean blood loss in the treatment group. The side-effectsencountered in the treatment group were mild and well acceptedby the women. Oral misoprostol is an effective and safe methodfor cervical dilatation prior to vacuum aspiration in firsttrimester pregnancy. 相似文献
93.
Chung H. Kim MD Alan R. Zinsmeister PhD Juan-R. Malagelada MD 《Digestive diseases and sciences》1988,33(2):193-199
The effect of electrical dysrhythmias on the mechanical activity of the fed stomach was investigated in 5 conscious dogs implanted with Ag-AgCl electrodes and strain gauge force transducers. Each dog was fed 1 can of ALPO® and electromechanical activities of the stomach were recorded for the next 120 min. The results show that intraarterial boluses of met-enkephalin (75 g/kg), PGE2 (36 g/kg), and epinephrine (36 g/kg) induced episodes of antral dysrhythmias whereas saline (1 cc) did not. The postcibal antrat motility index for the test period was not altered following saline injection, but it was reduced by 61%, 70%, and 81% following the administration of met-enkephalin, epinephrine, and PGE2, respectively (p<0.01 vs. baseline period). During periods of normal electrical rhythm, PGE2 and epinephrine significantly reduced the antral motility index (2.07±0.93 and 3.24±0.79, respectively) vs. saline (7.92±0.44) (p<0.05 for both drugs) whereas met-enkephalin (4.98±0.56) did not. In contrast, during episodes of dysrhythmia, met-enkephalin significantly depressed antral motility (1.70±0.74) (p<0.05 vs. periods with normal electrical rhythm) whereas neither epinephrine nor PGE2 caused a further reduction in antral motility from what was seen during periods of normal electrical rhythm (1.84±0.72 and 1.34±0.37, respectively). We thus conclude that intraarterial administration of met-enkephalin, PGE2, or epinephrine induce gastric dysrhythmias postcibally and depress antral contractile activity. The relaxatory effect of met-enkephalin on antral contractions is primarily due to its dysrhythmic effect whereas PGE2 and epinephrine inhibit antral motility even when the electrical rhythm is undisturbed.This work was supported in part by the USPHS, NIH grants AM26428, AM07198, and AM34988 and the Mayo Foundation. 相似文献
94.
Yang Hee Lee Ihn Rhan Lee Won Sick Won Chung Hee Park 《Archives of pharmacal research》1988,11(3):247-249
95.
L C Schlichter P A Pahapill I Chung 《The Journal of pharmacology and experimental therapeutics》1992,261(2):438-446
Originally developed as antidotes to organophosphorus nerve poisons, the oximes have attracted renewed interest in studies of cellular regulation. In particular, 2,3-butanedione monoxime (BDM) has gained attention as a useful membrane-permeant "chemical phosphatase" for studying roles of protein phosphorylation. It has been proposed that effects of BDM on cardiac muscle tension, action potentials, neuromuscular transmission and ion currents are related to dephosphorylation of substrates as diverse as myofibrils and ion channels. In the present study, voltage-dependent K+ currents in human T lymphocytes were studied using the whole cell patch clamp technique. Preincubating intact cells briefly in 5 mM BDM before recording reduced the K+ current in an irreversible manner, consistent with chemical (phosphatase?) modification of the channels. In contrast, acute BDM treatment produced a rapid, reversible block of K+ current with half block at about 5 mM. Moreover, including adenosine-O-5'-(3-thiotriphosphate) (500 microM) in the patch pipette did not prevent the rapid, reversible block by BDM. Under these conditions, the most likely mechanism was a direct block of channels from the outside. Because similar K+ currents are present in many tissue and cell types, a direct channel block suggests caution in interpreting the effects of oximes as resulting from protein dephosphorylation. 相似文献
96.
Test of genetic heterogeneity of cleft lip with or without cleft palate as related to race and severity 总被引:6,自引:0,他引:6
The question of possible heterogeneity among population groups and phenotypic groups on the role of major gene in the etiology of cleft lip with or without cleft palate [CL(P)] was examined using the uniformly collected data in Hawaii. Complex segregation analysis was used to analyze patterns of family resemblance under the mixed model incorporating the effects of major gene and multifactorial inheritance. Analysis of the entire data showed superior fit of the mixed model including the effects of both major gene and multifactorial inheritance over the model of major gene alone or multifactorial inheritance alone. No significant heterogeneity could be detected between the high-incidence group (Oriental or Japanese) and the low-incidence group (non-Oriental) in the underlying general model, although higher heritability was observed in general. When families were classified into "severe" and "mild" phenotypes based on cleft lip vs. cleft lip and palate or unilateral vs. bilateral cleft in the proband, no significant differences could be detected between the two types in the underlying genetic model. 相似文献
97.
Füst G Arason GJ Kramer J Szalai C Duba J Yang Y Chung EK Zhou B Blanchong CA Lokki ML Bödvarsson S Prohászka Z Karádi I Vatay A Kovács M Romics L Thorgeirsson G Yu CY 《International immunology》2004,16(10):1507-1514
The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking. 相似文献
98.
YopB is a 401-amino-acid protein that is secreted by a plasmid-encoded type III secretion system in pathogenic Yersinia species. YopB is required for Yersinia spp. to translocate across the host plasma membrane a set of secreted effector proteins that function to counteract immune signaling responses and to induce apoptosis. YopB contains two predicted transmembrane helices (residues 166 to 188 and 228 to 250) that are thought to insert into the host plasma membrane during translocation. YopB is also required for pore formation and host-cell-signaling responses to the type III machinery, and these functions of YopB may also require membrane insertion. To elucidate the importance of membrane insertion for YopB function, YopB proteins containing helix-disrupting double consecutive proline substitutions in the center of each transmembrane domain were constructed. Yersinia pseudotuberculosis strains expressing the mutant YopB proteins were used to infect macrophages or epithelial cells. Effector translocation, pore formation, and host-cell-signaling responses were studied. Introduction of helix-disrupting substitutions into the second transmembrane domain of YopB resulted in a nonfunctional protein that was not secreted by the type III machinery. Introduction of helix-disrupting substitutions into the first transmembrane domain of YopB resulted in a protein that was fully functional for secretion and for interaction with YopD, another component of the translocation machinery. However, the YopB protein with helix-disrupting substitutions in the first transmembrane domain was partially defective for translocation, pore formation, and signaling, suggesting that all three functions of YopB involve insertion into host membrane. 相似文献
99.
Leukocyte apoptosis and its significance in sepsis and shock 总被引:12,自引:0,他引:12
Sepsis and multiple organ failure continue to be significant problems among trauma, burn, and the critically ill patient population. Thus, a number of laboratories have focused on understanding the role of altered apoptotic cell death in contributing to immune and organ dysfunction seen in sepsis and shock. Immune cells that undergo altered apoptotic changes include neutrophils, macrophages, dendritic cells, as well as various lymphocyte populations. Evidence of epithelial as well as endothelial cell apoptotic changes has also been reported. Although mediators such as steroids, tumor necrosis factor, nitric oxide, C5a, and Fas ligand (FasL) appear to contribute to the apoptotic changes, their effects are tissue- and cell population-selective. As inhibiting Fas-FasL signaling (e.g., gene deficiency, Fas fusion protein, or Fas short interfering RNA administration), caspase inhibition (caspase mimetic peptides), and/or the overexpression of downstream antiapoptotic molecules (e.g., Bcl-2, Akt) improve survival of septic mice, it not only demonstrates the pathological significance of this process but points to novel targets for the treatment of sepsis. 相似文献
100.
Systematic changes in gene expression in postmortem human brains associated with tissue pH and terminal medical conditions 总被引:8,自引:0,他引:8