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1.
A new classification of forms of progressive systemic scleroderma (PSS) is presented. Compared with previous classifications, it includes not only frequent, typical forms of PSS, but also rarer manifestations. For the first time, it considers pathogenetic factors, such as the phenomena which have become known concerning the immunological system, and distinguishes between noninflammatory and inflammatory subtypes. Etiological (in this case, immunogenetic) criteria are also considered. This classification is open to further differentiation and development.  相似文献   
2.
Tick-borne encephalitis (TBE) virus is an important human pathogenic flavivirus that is endemic in Europe and Asia. The disease can be effectively prevented by inactivated vaccines and vaccination breakthroughs (VBTs) are rare. We investigated the characteristics of antibody responses in such VBTs in comparison to those in unvaccinated TBE patients. In contrast to the unvaccinated controls, most of the VBTs displayed a delayed IgM antibody response and had high avidity and strongly neutralizing antibodies already in the first sample taken upon hospitalization. The antibody profile of these patients therefore had the characteristics of an anamnestic immune response. In the VBTs analyzed, immunological priming and memory were apparently not sufficient or fast enough to prevent the disease.  相似文献   
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4.
The incidence of erectile dysfunction in patients with long-term diabetes mellitus can be as high as 50%. Diabetic microangiopathy is regarded as the most important pathogenic factor. In this review of a group of 210 impotent patients evaluated and treated at our centre we report on the examination data (angiopathy, neuropathy, psychogenic factors) in 36 patients with diabetes in comparison with the corresponding findings in 169 non-diabetic patients. In 5 patients erectile dysfunction had actually preceded the clinical manifestations of diabetes mellitus. Autoinjection therapy was started in 62% of all the diabetic patients, since this is effective, minimally invasive and, therefore, applicable to a large group of patients. This form of therapy was accepted by 90% of our patients' partners, which is in accordance to the reports in the literature. However, treatment had to be interrupted in 2 out of the 22 patients, owing to lack of cooperation on the part of the sexual partner. No complications were attributable to autoinjection therapy.  相似文献   
5.
1. Coronary arteries from bovines (BCA) and pigs (PCA) were used for measuring endothelium-dependent relaxation in the presence of L-NG nitroarginine and indomethacin. As some compounds tested have been found to have an inhibitory effect on autacoid-activated endothelial Ca2+ signalling, endothelium-dependent relaxation was initiated with the Ca2+ ionophore A23187. 2. The common compounds for modulating arachidonic acid release/pathway, mepacrine and econazole only inhibited L-NG nitroarginine-resistant relaxation in BCA not in PCA. In contrast, proadifen (SKF 525A) diminished relaxation in BCA and PCA. Mepacrine and proadifen inhibited Hoe-234-initiated relaxation in BCA and PCA, while econazole only inhibited Hoe 234-induced relaxation in PCA. Due to the multiple effects of these compounds, caution is necessary in the interpretation of results obtained with these compounds. 3. The inhibitor of Ca(2+)-activated K+ channels, apamin, strongly attenuated A23187-induced L-NG nitroarginine-resistant relaxation in BCA while apamin did not affect L-NG nitroarginine-resistant relaxation in PCA. 4. Pertussis toxin blunted L-NG nitroarginine-resistant relaxation in BCA, while relaxation of PCA was not affected by pertussis toxin. 5. Thiopentone sodium inhibited endothelial cytochrome P450 epoxygenase (EPO) in PCA but not in BCA, while L-NG nitroarginine-resistant relaxation of BCA and PCA were unchanged. Protoporphyrine IX inhibited EPO in BCA and PCA and abolished L-NG nitroarginine-resistant relaxation of BCA not PCA. 6. An EPO-derived compound, 11,12-epoxy-eicosatrienoic acid (11,12-EET) yielded significant relaxation in BCA and PCA in three out of six experiments. 7. These findings suggest that L-NG nitroarginine-resistant relaxation in BCA and PCA constitutes two distinct pathways. In BCA, activation of Ca(2+)-activated K+ channels via a pertussis-toxin-sensitive G protein and EPO-derived compounds might be involved. In PCA, no selective inhibition of L-NG nitroarginine-resistant relaxation was found.  相似文献   
6.
Little is known about the role of peripheral blood mononuclear cells (PBMCs) in lipopolysaccharide (LPS) elimination. We studied the endotoxin elimination capacities (EEC) of PBMCs of 15 healthy volunteers, 13 patients with sepsis, and 1 patient suffering from paroxysmal nocturnal hemoglobinuria (PNH). Although expression of CD14, the best-characterized receptor for LPS to date, was reduced from 93.6% ± 0.8% in healthy subjects to 50.5% ± 6.5% in patients with sepsis and was 0.3% in a patient with septic PNH, EEC were found to be unchanged. There was no difference in the amount of tumor necrosis factor alpha (TNF-α) released by PBMCs of healthy donors and patients with sepsis. Anti-CD14 antibodies (MEM-18) completely suppressed EEC, binding of fluorescein isothiocyanate-labeled LPS to monocytes as determined by FACScan analysis, and TNF-α release in all three groups studied. The concentrations of soluble CD14 (sCD14) secreted by endotoxin-stimulated PBMCs from healthy donors and patients with sepsis amounted to 4.5 ± 0.4 and 20.1 ± 1.8 ng/ml, respectively. Based on our results, we suggest that PBMCs eliminate LPS by at least two different mechanisms; in healthy subjects, the membrane CD14 (mCD14) receptor is the most important factor for LPS elimination, while in patients with sepsis (including the septic state of PNH), increased sCD14 participates in LPS elimination. Secretion of sCD14 is strongly enhanced under conditions of low expression of mCD14 in order to counteract the reduction of mCD14 and maintain the function of monocytes. This sCD14 may substitute the role of mCD14 in LPS elimination during sepsis. The elimination of LPS by PBMCs correlates with the binding reaction and the secretion of TNF-α.  相似文献   
7.
Gains of 13q are correlated with a poor prognosis in liposarcoma.   总被引:2,自引:0,他引:2  
Liposarcomas are a phenotypical heterogeneous group of tumors divided into four main subtypes: well-differentiated, dedifferentiated, myxoid/round cell, and pleomorphic. The aim of this study was to compare DNA sequence copy number changes of these subtypes as investigated by comparative genomic hybridization in 36 patients. Comparative genomic hybridization revealed genomic imbalances in tumors of 27 patients (mean 5.6 imbalances per tumor). The most frequent gains were within single regions of 1q, 12q, and 13q. We found a significant correlation of poor overall survival and gain of 13q21 (P=0.0221), 13q22 (P=0.0341), 13q31 (P=0.0410), and 13q32 (P=0.0074). The univariate Cox regression analysis revealed an increased risk of tumor-related death for patients whose liposarcomas possess with gains of 13q21 and 13q32 simultaneously (P=0.010; RR=7.1; 95% CI 1.6-31.7). Furthermore, 12 high-level amplifications were found in tumors of seven patients. In four cases 12q14-q15 and in two cases 13q32-q33 were amplified. We identified in different liposarcoma subtypes characteristic genomic changes: Gains and high-level amplifications of 12q occurred in all 11 investigated well-differentiated liposarcomas, and these changes were often present simultaneously with gains of 1q (mean 5.5 changes). In the two dedifferentiated liposarcomas, gains of 1q in both liposarcomas, and a high-level amplification of 13q were striking. Only eight of the 17 patients with myxoid/round cell liposarcomas showed changes in DNA copy number (mean 3.4 imbalances). In four of these eight cases gains of 13q occurred. The six pleomorphic liposarcomas possessed the most frequent genomic imbalances (mean number 16.3) of all liposarcoma subtypes investigated. These imbalances were in almost all chromosomal regions detected predominantly as over-representations of chromosomes 1, 5p, 13q, and 22q. Summarizing, all subtypes but well-differentiated liposarcomas showed gains of 13q, which were associated with a poor prognosis.  相似文献   
8.
Zusammenfassung Die Ausscheidung an Ketopentosen im normalen 12 Std-Harn liegt in der Größenordnung von 1–7 mg.Eine direkte quantitative Bestimmung dieser Ketopentosen mit der Cystein-Carbazol-Reaktion ist nicht möglich, da durch nichtidentifizierte Cystein-Carbazolpositive Substanzen zu hohe Werte vorgetäuscht werden. Nur Säulenchromatographie und papierchromatographische Analyse kann zuverlässige Werte liefern.Nach intravenöser Belastung mit 20 g Xylit wird bei 5 von 9 Fällen ein geringfügiger Anstieg der Ketopentose-Ausscheidung gefunden.Nach oraler Belastung mit 20 g D-Xylose steigt die Ketopentose-Ausscheidung im Harn auf etwa das 100fache der Norm an. Es handelt sich um D-Xylulose und Ribulose. Als Ursache für diese vermehrte Ausscheidung an Ketopentosen wird eine Hemmung der Transketolase durch Xylose angenommen.
Summary The normal urinary excretion of ketopentoses during a period of 12 hrs is found to be in the range of 1 to 7 mg. The direct colorimetric assay of ketopentoses in the urine with cysteine-carbazol gives to high values due to unidentified cysteine-carbazol positiv material. Only by column chromatography and paper chromatography reliable data can be obtained.After intravenous injection of 20 g xylitol only in 5 out of 9 cases a slight increase in ketopentose excretion can be found.After oral administration of 20 g D-xylose there is a roughly 100fold increase in ketopentose excretion, consisting of D-xylulose and ribulose. It is assumed that this increase in ketopentose excretion is the result of an inhibition of transketolase by xylose.Frl.Käthe Wagner danken wir für stets zuverlässige technische Assistenz.
  相似文献   
9.
 Energy-rich phosphates, [ATP]/[ADPfree] ratios, and the myosin heavy chain (MHC) complement were determined in single fibres from normal rabbit muscles, and in fibres isolated from tibialis anterior muscle undergoing fast-to-slow conversion by chronic low-frequency stimulation (CLFS). In normal muscles, energy-rich phosphate contents and [ATP]/[ADPfree] ratios could thus be assigned to different MHC-based fibre types. Phosphocreatine (PCr) contents and [ATP]/[ADPfree] ratios differed markedly between fast- and slow-twitch fibres, as well as within the fast fibre subtypes. Both magnitudes were approximately twofold higher in the fastest (type IIB) fibres as compared to the slowest (type I) fibres. According to PCr contents and [ATP]/[ADPfree] ratios pure and hybrid fibres were aligned in an order similar to that determined by their contractile properties and myofibrillar ATPase activities. CLFS for up to 30 days induced pronounced decreases in PCr and [ATP]/[ADPfree] which attained levels twofold lower than in normal slow-twitch fibres. In both normal and stimulated muscles, PCr and [ATP]/[ADPfree] ratios were correlated, indicating their equilibrium in the different fibre types. The relationship detected between MHC isoform expression and the [ATP]/[ADPfree] ratio suggests that the drastic and persistent depression of the cellular energy state may act as an important signal initiating fast-to-slow transformation processes in muscle fibres. Received: 26 June 1998 / Accepted: 31 July 1998  相似文献   
10.
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