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排序方式: 共有642条查询结果,搜索用时 15 毫秒
51.
The relative bioavailability of metoprolol following oral and rectal administration to volunteers and patients 总被引:1,自引:0,他引:1
F.M. de Stoppelaar L.M.L. Stolk A.J. Beysens J.L.M. Stappers AP.M. Gorgels 《Pharmacy World & Science》1999,21(5):233-238
The pharmacokinetics, efficacy and safety of metoprolol tartrate 25 mg fatty suppositories were studied in 5 healthy volunteers and in 8 patients suffering from instable angina pectoris. Metoprolol 25 mg capsules were used as a control oral dosage form. Metoprolol showed a considerable rectal bioavailability (AUC, C max) and was absorbed quickly from the rectum (T max). In both groups rectal bioavailability was comparable. However, oral bioavailability was much lower in the volunteer group than in the patient group. Furthermore, ratios of metoprolol/aOHmetoprolol concentrations in plasma and urine gave an indication for a partial avoidance of the first pass effect after rectal administration. Further research is necessary to define an exact rectal dosage of metoprolol. In all patients, a substantial drop in heart rate, systolic and diastolic blood pressure was seen after administration of the first suppository. Metoprolol suppositories appear to be an effective, safe and suitable alternative for patients who are in need for beta blocking medication and who are unable to take oral medication for a certain amount of time. 相似文献
52.
Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations. 相似文献
53.
Jia Qin Aleksey V. Zima Maura Porta Lothar A. Blatter Michael Fill 《Pflügers Archiv : European journal of physiology》2009,458(4):643-651
Trifluoperazine (TFP), a phenothiazine, is a commonly used antipsychotic drug whose therapeutic effects are attributed to
its central anti-adrenergic and anti-dopaminergic actions. However, TFP is also a calmodulin (CaM) antagonist and alters the
Ca2+ binding properties of calsequestrin (CSQ). The CaM and CSQ proteins are known modulators of sarcoplasmic reticulum (SR) Ca2+ release in ventricular myocytes. We explored TFP actions on cardiac SR Ca2+ release in cells and single type-2 ryanodine receptor (RyR2) channel activity in bilayers. In intact and permeabilized ventricular
myocytes, TFP produced an initial activation of RyR2-mediated SR Ca2+ release and over time depleted SR Ca2+ content. At the single channel level, TFP or nortryptiline (NRT; a tricyclic antidepressant also known to modify CSQ Ca2+ binding) increased the open probability (Po) of CSQ-free channels with an EC50 of 5.2 μM or 8.9 μM (respectively). This Po increase was due to elevated open event frequency at low drug concentrations
while longer mean open events sustained Po at higher drug concentrations. Activation of RyR2 by TFP occurred in the presence
or absence of CaM. TFP may also inhibit SR Ca uptake as well as increase RyR2 opening. Our results suggest TFP and NRT can
alter RyR2 function by interacting with the channel protein directly, independent of its actions on CSQ or CaM. This direct
action may contribute to the clinical adverse cardiac side effects associated with these drugs. 相似文献
54.
Kalousová M Sulková S Zima T Deppisch R Beck W Bednárová sV Fortová M Tesar V 《Renal failure》2003,25(2):277-286
Advanced glycation end products (AGEs) and other carbonyl and oxidative stress compounds are supposed to play a critical role in the pathogenesis of several diseases and their complications, i.e., diabetes mellitus, diabetic retinopathy, atherosclerosis, and chronic renal failure. In the present investigation, we were interested in the relationship of AGEs in plasma to other prominent factors in the patients on chronic hemodialysis treatment-27 patients with diabetes mellitus, 35 patients without diabetes mellitus. AGE-group reactivity was estimated using a spectrofluorometric method (excitation 350 nm, emission 430 nm) and is expressed in arbitrary units (AU). We found significantly higher AGEs levels in diabetics than in non-diabetics on regular hemodialysis treatment both before (2.7 +/- 0.7 x 10(4) AU vs. 2.2 +/- 0.6 x 10(4) AU, p < 0.001) and after the dialysis session (2.3 +/- 0.5 x 10(4) AU vs. 1.8 +/- 0.7 x 10(4) AU, p < 0.005). AGEs were significantly reduced during hemodialysis in both groups of patients--by 15.4% in the diabetic go (p < 0.001) and by 17.3% in non-diabetics (p < 0.005). In the patients with diabetes mellitus, AGEs did not correlate with parameters of the glucose metabolism correction (blood glucose, HbA1c). We observed a significant correlation between AGEs and leptin (r = 0.48, p < 0.05) as well as the leptin/body fat ratio (r = 0.56, p < 0.05) only in hemodialyzed patients with diabetes mellitus. These findings suggest more detailed studies to identify the molecular links between carbonyl stress, i.e., advanced glycation end products, and leptin metabolism, sign of microinflammation and hypertension. 相似文献
55.
Bile duct obstruction: radiologic evaluation of level, cause, and tumor resectability 总被引:6,自引:0,他引:6
Gibson RN; Yeung E; Thompson JN; Carr DH; Hemingway AP; Bradpiece HA; Benjamin IS; Blumgart LH; Allison DJ 《Radiology》1986,160(1):43-47
In a prospective study of 65 patients with bile duct obstruction, various radiologic modalities were compared for their capability to demonstrate the level and cause of obstruction and to indicate accurately tumor resectability. Ultrasound (US) was performed in 65 patients, computed tomography (CT) in 51, direct cholangiography (DC) in 57, and angiography in 35. The level of obstruction was correctly indicated by US in 95% of patients and by CT in 90%, and the cause was correctly indicated by US in 88%, by CT in 63%, and by DC in 89%. In predicting tumor resectability, US was correct in 71% of patients, compared with 42% for CT, 58% for DC, and 25% for angiography. US therefore appears to be the single most useful modality in the evaluation bile duct obstruction. 相似文献
56.
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
57.
P Stern B Friedecky V Bartos D Bezdickova J Vavrova J Uhrova L Rozprimova T Zima V Palicka 《Clinical chemistry and laboratory medicine》2001,39(12):1278-1282
We compared six routinely employed immunoassay kits: Architect i2000 and AxSYM, Abbott Laboratories; Elecsys 2010, Roche Diagnostics; ELSA, CIS-BioInternational; Immulite 1, Diagnostic Products Corporation; and IRMA-mat, Byk-Sangtec Diagnostica. Using all analytical systems, we measured identical groups of clinical samples completed with selected control samples. The repeatability of measurements (coefficient of variation) ranged from 2.1% (Elecsys 2010) to 6.7% (ELSA). The parameters of Passing-Bablok regression show significant systematic differences among analytical systems. Data from a Bland-Altman diagram suggest that these differences project onto other, still more significant individual differences among individual samples. Though the cut-off values differ between various systems, no similar clinical efficacy appears to be attained. The behavior of individual systems is quite different for identical control materials and does not necessarily duplicate the calibration for biological samples. The results of determining CA 19-9 cannot be extrapolated from one analytical technique to another, even in cases where the same monoclonal antibody is used. Standardization of CA 19-9 measurement systems is necessary to allow use of the results for the purposes of evidence-based medicine. 相似文献
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