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排序方式: 共有368条查询结果,搜索用时 15 毫秒
1.
2.
Mulkerrin EC; Clark BA; Epstein FH 《QJM : monthly journal of the Association of Physicians》1997,90(6):411-415
We studied blood pressure and natriuretic responses to acute salt loading,
and the effect of non-steroidal anti-inflammatory agents on these
responses, in five healthy normotensive women aged 65 to 71 years. Five
women aged 25 to 31 years acted as controls. Intravenous saline loading,
with and without prior ingestion of ibuprofen, was 15 ml/kg/h for 3 h.
Baseline blood pressures were higher in the elderly. Saline infusion
without ibuprofen raised systolic blood pressure (SBP) by about 25 mmHg in
the older group only. Ibuprofen increased baseline SBP in the elderly (129
+/- 6 vs. 116 +/- 5 mmHg, p < 0.05). Saline loading after ibuprofen
again raised blood pressure by about 25 mmHg in the elderly only. The
elderly group showed markedly increased sodium excretion during saline
loading, but this was reduced by ibuprofen. Ibuprofen had no effect on SBP
or sodium excretion in controls. Ageing appears to increase susceptibility
to salt retention and hypertension from non-steroidal anti-inflammatory
agents.
相似文献
3.
Acute thoracic aortic dissection has a high mortality if untreated, so the diagnosis must be rapidly made if mortality is to be lowered significantly. Multiple imaging techniques are often used. This retrospective study from 1988 to 1993 assesses the usefulness in diagnosis of chest X-rays, computed tomography (CT) scanning, aortography, magnetic resonance imaging (MRI), trans-thoracic (TTE) and trans-oesophageal (TOE) echocardiography. Forty-two patients with a final clinical diagnosis of dissection were studied. The diagnosis was confirmed in 16 (13 at surgery and three at autopsy). Three died with dissection given as the only cause for death. Chest X-ray abnormalities were seen in all 19 patients with surgery or death from dissection, with a widened mediastinum and/or dilated aorta being present in 17. In the group of 16 patients with surgery or autopsy proof, CT scans found dissections in 9 of 12 patients studied and correctly classified the type in only five. Aortography was performed in five, with accurate depiction of dissection and type in all. TTE found dissections in three of eight patients imaged by this method. MRI and TOE were performed each on two patients, with accurate depiction of dissection and type in each. Because of the relatively low sensitivity of CT scanning in defining aortic dissections Westmead Hospital is currently assessing the use of TOE as the prime imaging modality prior to surgical intervention. 相似文献
4.
Castillo S Reyes G Tejedor D Mozas P Suarez Y Lasuncion MA Cenarro A Civeira F Alonso R Mata P Pocovi M;Spanish Group of FH 《Human mutation》2002,20(6):477
Familial hypercholesterolemia is a genetic disorder caused by mutations in the LDL receptor gene. During a survey of mutations of LDL receptor gene in Spanish FH patients we found two mutations in the same allele: a missense N543H mutation in exon 11 and a 9bp inframe deletion (2393del9) located in exon 17. This double mutant allele was founded in 10 out of 458 unrelated patients: one homozygous FH [N543H+2393del9] + [N543H+2393del9], one compound heterozygote [N543H+2393del9] + [W-18X+E256K] and 8 heterozygotes. Flow cytometric analysis showed a defective LDL binding (20% of normal value) and internalization (23%) in lymphocytes from the homozygous patient; furthermore, studies of mitogen-stimulated lymphocytes demonstrated that the ability of LDL to support cell proliferation was impaired. Unexpectedly, not all carriers of the double mutant allele develop hypercholesterolemia and, furthermore, cholesterol-lowering treatment of the homozygous patient resulted in a 58% LDL cholesterol reduction. In conclusion, the phenotypic expression in the homozygous and heterozygous patients presented here, as well as the LDL-receptor residual activity, allowed the classification of this mutation as mild extending the group of mild mutations found at homozygosity. 相似文献
5.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
6.
B H Faas P A Maaskant-van Wijk E A Beuling M A Overbeeke C E van der Schoot G C Christiaens 《Nederlands tijdschrift voor geneeskunde》1999,143(36):1804-1807
Rhesus (Rh) and Kell blood group immunisations are the most frequent causes of haemolytic disease of the newborn. Recently, the molecular bases of the Rh and Kell antigens have been elucidated. Subsequently, specific polymerase chain reactions (PCRs) could be developed to determine the RhD, RhC/Rhc and RhE/Rhe genotypes as well as the KI genotype (from the Kell blood group) with genomic DNA. The tests were applied to genomically determine the foetal Rh and Kell blood groups with DNA obtained from amniotic fluid cells. The genotypes obtained were compared with the Rh phenotypes established by cord blood red cell serology. The PCRs to determine the RhD, Rhc, RhE and Rhe and KI genotypes were found to be reliable. The test for RhC however, resulted in false-positive C genotypes. Indeed, more than half of the subsequently tested C-negative Negroid donors were false-positive with the DNA test. Thus, except for RhC, it is possible to reliably determine the Rh and KI genotypes of a foetus with DNA isolated from amniotic fluid cells. Amniocentesis, however, carries a risk for the pregnancy and therefore the tests will only be justified in pregnant women in whom an antibody has been detected and the father of the foetus is heterozygous for the specific antigen. Recently foetal RhD genotypes were determined in foetal DNA circulating in the plasma of RhD-negative pregnant women. This could eventually lead to the introduction of assays with which the foetal blood group can be determined without any risk to the foetus. 相似文献
7.
A. Muttray L. Klimek M. Faas D. Schäfer W. Mann J. Konietzko 《International archives of occupational and environmental health》1999,72(7):485-488
Objectives: Irritating effects of organic solvents have usually been measured by means of questionnaires. The aim of the present study
was to evaluate the sensitivity of different methods of detecting subclinical irritating effects. Methods: Twelve healthy, non-smoking students were exposed to 200 ppm and to 20 ppm 1,1,1-trichloroethane in an exposure chamber,
using a crossover design. The amounts of interleukins (IL)-1β, IL-6 and IL-8 and prostaglandin E2 (PGE2) in nasal secretions were measured. Mucociliary transport time was determined with the saccharine test. Ciliary beat frequency
of nasal epithelial cells was measured with video-interference contrast microscopy. Subjective symptoms were assessed by questionnaire.
Results: Concentrations of ILs were significantly elevated after exposure to 200 ppm 1,1,1-trichloroethane (IL-1β 82.4 vs. 28.8 pg/ml
(medians), P=0.003; IL-6 12.2 vs. 7.2 pg/ml, P=0.01; IL-8 549 vs. 424 pg/ml, P=0.007), whereas the other parameters remained unchanged. Conclusion: The interleukins measured proved to be sensitive indicators of irritating effects of 1,1,1-trichloroethane. The German threshold
limit (MAK value) of 200 ppm 1,1,1-trichloroethane does not prevent the subclinical inflammation of nasal mucosa.
Received: 3 March 1999 / Accepted: 14 June 1999 相似文献
8.
9.
Diabetes,plasma insulin,and cardiovascular disease: subgroup analysis from the Department of Veterans Affairs high-density lipoprotein intervention trial (VA-HIT) 总被引:15,自引:0,他引:15
Rubins HB Robins SJ Collins D Nelson DB Elam MB Schaefer EJ Faas FH Anderson JW 《Archives of internal medicine》2002,162(22):2597-2604
BACKGROUND: Diabetes mellitus, impaired fasting glucose level, or insulin resistance are associated with increased risk of cardiovascular disease. OBJECTIVES: To determine the efficacy of gemfibrozil in subjects with varying levels of glucose tolerance or hyperinsulinemia and to examine the association between diabetes status and glucose and insulin levels and risk of cardiovascular outcomes. METHODS: Subgroup analyses from the Department of Veterans Affairs High-Density Lipoprotein Intervention Trial, a randomized controlled trial that enrolled 2531 men with coronary heart disease (CHD), a high-density lipoprotein cholesterol level of 40 mg/dL or less (=1.04 mmol/L), and a low-density lipoprotein cholesterol level of 140 mg/dL or less (=3.63 mmol/L). Subjects received either gemfibrozil (1200 mg/d) or matching placebo and were followed up for an average of 5.1 years. In this article, we report the composite end point (CHD death, stroke, or myocardial infarction). RESULTS: Compared with those with a normal fasting glucose level, risk was increased in subjects with known diabetes (hazard ratio [HR], 1.87; 95% confidence interval [CI], 1.44-2.43; P =.001) and those with newly diagnosed diabetes (HR, 1.72; 95% CI, 1.10-2.68; P =.02). In persons without diabetes, a fasting plasma insulin level of 39 micro U/mL or greater (>/=271 pmol/L) was associated with a 31% increased risk of events (P =.03). Gemfibrozil was effective in persons with diabetes (risk reduction for composite end point, 32%; P =.004). The reduction in CHD death was 41% (HR, 0.59; 95% CI, 0.39-0.91; P =.02). Among individuals without diabetes, gemfibrozil was most efficacious for those in the highest fasting plasma insulin level quartile (risk reduction, 35%; P =.04). CONCLUSION: In men with CHD and a low high-density lipoprotein cholesterol level, gemfibrozil use was associated with a reduction in major cardiovascular events in persons with diabetes and in nondiabetic subjects with a high fasting plasma insulin level. 相似文献
10.
Erythropoietin production in a primary culture of human renal carcinoma cells maintained in nude mice 总被引:4,自引:1,他引:4
The present studies report erythropoietin (Ep) production in primary cultures of a human renal carcinoma from a patient with erythrocytosis that has been serially transplanted to BALB/c nude mice. The levels of erythropoietin in the culture media were estimated using the exhypoxic polycythemic mouse assay (EHPCMA), fetal mouse liver erythroid colony- forming technique (FMLC), and a radioimmunoassay (RIA). The spent culture media of the exponentially growing cells contained less than 10 mU/ml of Ep measured by RIA. However, after the cells became confluent, Ep levels (RIA) in the spent media showed a marked increase to approximately 300 mU/ml. Ep levels estimated using the FMLC and EHPCMA were approximately 2/3 and 1/10, respectively, of those measured by RIA. Rabbit antiserum to highly purified human urinary Ep (70,400 U/mg protein) was utilized for immunocytochemical (peroxidase-antiperoxidase method) localization of Ep in the cultured cells. Very few of the cells in exponential growth exhibited Ep-like immunoreactivity, whereas intense Ep-like immunoreactivity was observed in the cytoplasm of the cells maintained in culture for a prolonged period after reaching confluency. The most intense staining was observed in some of the cells forming domes. The domes developed after the cells reached confluency, and their numbers increased with increasing time in confluent culture, in parallel with the increase in Ep levels in the spent media. This primary cell culture system of a renal cell carcinoma maintained in nude mice, which produces immunologically and biologically active Ep, may provide a useful model for studies of the mechanism of Ep production. 相似文献