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41.
42.
Changes in regional cerebral blood flow during brain maturation in children and adolescents. 总被引:25,自引:0,他引:25
C Chiron C Raynaud B Mazière M Zilbovicius L Laflamme M C Masure O Dulac M Bourguignon A Syrota 《Journal of nuclear medicine》1992,33(5):696-703
Regional cerebral blood flow (rCBF) was studied by SPECT using 133Xe in 42 children, aged 2 days to 19 years, considered as neurologically normal. rCBF was measured on cortical regions and on the cerebellum and thalamus. Curves for reference values and standard deviation were defined for each region. At birth, cortical rCBFs were lower than those for adults; after birth they increased until 5 or 6 yr of age to values 50%-85% higher than those for adults and thereafter decreased, reaching adult levels between 15 and 19 yr. Neonatal values of rCBF on cerebellum and thalamus were slightly higher than adult level, but not significantly; after age 1, they followed the common pattern for cortical curves. When rCBFs were expressed in percent global CBF, they were lower at birth than adult levels in the cortex, then increased and reached a plateau corresponding to the adult value before the second year of age. The time needed to reach normal adult values differed for each cortical region. The shortest time was found on the primary cortex and the longest on the associative cortex. Cognitive development of the child seems to be related to changes in blood flow of the corresponding brain regions. 相似文献
43.
H M Blottière A Menoret C Burg J Y Douillard J Le Pendu 《International journal of cancer. Journal international du cancer》1992,50(2):315-320
Sera from BDIX rats inoculated with 2 tumor clones derived from a single syngeneic colon carcinoma were assayed by Western blotting for the presence of antibodies against the grafted tumor. The PROb clone is progressive and produces metastases. We observed that rats bearing this tumor developed antibodies against an unglycosylated water-soluble protein of 105 kDa. The magnitude of this humoral response, as assessed by the intensity of the signal on immunoblots, was inversely correlated with survival of the rats. Furthermore, rats inoculated with the REGb clone, which is immunologically rejected, never developed detectable antibodies against the tumor. Antisera from rats injected with PROb tumor detected p105 antigen in cellular extracts from the REGb clone and from a series of rat and human cell lines. This protein was also detected in variable amounts in some normal adult and fetal tissues. Treatment of PROb or REGb cells by either interferon-gamma or heat shock did not significantly alter the expression of the p105 auto-antigen. 相似文献
44.
45.
C Monpère S Bertrand P Kapusta P Vernochet N Quilliet A Rajoelina 《Archives des maladies du coeur et des vaisseaux》1992,85(7):987-992
This study analysed the possibilities of returning to work of professional drivers after a cardiac event and rehabilitation. The population comprised 94 consecutive patients, all men, average age 48.8 years (range 30 to 63 years) referred after coronary bypass surgery (N = 39), myocardial infarction (N = 38), angina (N = 4) or valve replacement surgery (N = 13). Advice on professional reinsertion was given after the rehabilitation program, authorization to drive being given in the absence of cardiac symptoms, residual myocardial ischaemia, severe left ventricular dysfunction and serious ventricular arrhythmias. After 35 months, 4 patients were lost to follow-up; of the 90 remaining patients, the frequency of return to work (maximal at the 9th month) was 65.6% with 84.7% obtaining a renewal of their driving licence. In this series, 81% of patients were asymptomatic, 2 died, 16.7% had further cardiovascular complications. The morbidity and mortality were significantly greater in the group who had to stop driving (N = 40) (32.5% vs 8%, p < 0.001). Non complications occurred during work in those who resumed driving. This study confirms the safety of allowing low risk professional drivers, identified during cardiac rehabilitation by simple, reliable clinical and paraclinical criteria, to return to work. 相似文献
46.
Ivar Rønnestad Einar Thorsen Kåre Segadal Arvid Hope 《European journal of applied physiology》1994,69(1):32-35
In diving, pulmonary mechanical function is limited by the increased density of the gas breathed. Breathing cold and dry gas may cause an additional increase in airways resistance. We have measured forced vital capacity, forced expired volume in 1 s (FEV1) and forced midexpiratory flow rate (FEF25%–75%) before and after breathing dry or humid gas at 29–32°C during a standardized exercise intensity on a cycle ergometer at an ambient pressure of 3.7 MPa. The atmosphere was a helium and oxygen mixture with a density of 6.8 kg · m–3. Six professional saturation divers aged 26–37 years participated in the study. There were no significant differences in convective respiratory heat loss between the exposures. The mean evaporative heat loss was 67 W (range 59–89) breathing dry gas and 37 W (range 32–43) breathing humid gas, corresponding to water losses of 1.7 g · min–1 (range 1.5–2.2) and 0.9 g · min–1 (range 0.8–1.1), respectively. There was a significant reduction in FEV1 of 4.6 (SD 3.6)% (P<0.05), and in FEF25%–75% of 5.8 (SD 4.7)% (P<0.05) after breathing dry gas. There were no changes after breathing humid gas. By warming and humidifying the gas breathed in deep saturation diving bronchoconstriction may be prevented. 相似文献
47.
J Y Ranchére B Gordiani C Hassid 《Annales fran?aises d'anesthèsie et de rèanimation》1992,11(4):442-445
A new technique, the Cath Finder (Pharmacia Deltec) system, for locating central venous catheters is described. It was initially designed to facilitate the insertion of the PAS Port (Pharmacia Deltec), a long central venous catheter with an implantable chamber. It is based on a low intensity high frequency electromagnetic field generated by a locator wand. A preconnected sensor guide wire is introduced into the catheter so as to make the catheter tip detectable by the electromagnetic field. The wand is placed over an appropriate landmark on the anterior chest wall (third right rib, parasternally). When the centre of the field has been passed over by the sensor tip in the catheter-sensor assembly, a light signal is set off. This technique is simple and easily mastered. It is far less cumbersome than the usual techniques, like fluoroscopy and chest X-rays. The Cath Finder provides reliable continuous information on the position of the catheter tip during its insertion. It seems to provide an acceptable alternative to peroperative fluoroscopy. The accuracy of this system was assessed in ten patients. All had malignancies and required long term central venous access. In 6 cases, catheterisation and locating of the catheter were uneventful. In 2 cases, the catheter entered a wrong vein. The diagnosis having been made with the Cath Finder system, the false route was amended and the catheter placed accurately. In one case, the sensor in the catheter broke.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
48.
GillibertDuplantier J Neaud V Desmoulière A BioulacSage P Rosenbaum J 《Wound repair and regeneration》2005,13(1):A19-A19
Scarring of the cornea, the transparent tissue at the front of the eyeball, is an important cause of visual impairment. A major chemokine upregulated in tear fluid after corneal injury is platelet‐derived growth factor (PDGF), which induces the stromal cells of the cornea (keratocytes) to assume a fibroblastic phenotype. We have investigated the role of PDGF in matrix contraction by human corneal fibroblasts (HCF) using the standard three‐dimensional (3D) fibroblast‐populated collagen matrix model (FPCM).
When stimulated with PDGF, HCF in monolayer (2D) display circular ruffles (CR) on their dorsal surface. Using immunolabeling, we found that CR contain proteins of the Arp2/3 complex, which is required for the assembly of filamentous actin during protrusive activity. This PDGF‐mediated ruffling ability is altered by antibodies or blocking peptides that specifically interfere with the Arp2/3‐mediated pathway of actin polymerization, as well as by the myosin light chain kinase inhibitor, ML9. Preincubation with anti‐PDGF‐BB antibody or with the tyrosine kinase inhibitor, AG1295, also inhibits CR. While PDGF efficiently stimulates HCF‐mediated cell protrusive activity and macroscopic collagen gel contraction in the 3D model, this effect is directly inhibited by all the substances which inhibit CR in 2D, demonstrating a direct involvement of the PDGF‐mediated CR pathway in tissue contraction. Thus, 3D PDGF‐induced matrix contraction by HCF involves the same players as CR, a phenomenon observed in 2D cell cultures: PDGF‐BB receptor, receptor tyrosine kinase, the machinery for filamentous actin assembly (Arp 2/3 complex, Scar and Wasp proteins), and myosin. The functional role of circular ruffling or its equivalent in three‐dimensional fibroblast‐populated collagen matrices seems to be a rapid reorganization of the actin cytoskeleton in preparation for cell‐matrix interaction. 相似文献
When stimulated with PDGF, HCF in monolayer (2D) display circular ruffles (CR) on their dorsal surface. Using immunolabeling, we found that CR contain proteins of the Arp2/3 complex, which is required for the assembly of filamentous actin during protrusive activity. This PDGF‐mediated ruffling ability is altered by antibodies or blocking peptides that specifically interfere with the Arp2/3‐mediated pathway of actin polymerization, as well as by the myosin light chain kinase inhibitor, ML9. Preincubation with anti‐PDGF‐BB antibody or with the tyrosine kinase inhibitor, AG1295, also inhibits CR. While PDGF efficiently stimulates HCF‐mediated cell protrusive activity and macroscopic collagen gel contraction in the 3D model, this effect is directly inhibited by all the substances which inhibit CR in 2D, demonstrating a direct involvement of the PDGF‐mediated CR pathway in tissue contraction. Thus, 3D PDGF‐induced matrix contraction by HCF involves the same players as CR, a phenomenon observed in 2D cell cultures: PDGF‐BB receptor, receptor tyrosine kinase, the machinery for filamentous actin assembly (Arp 2/3 complex, Scar and Wasp proteins), and myosin. The functional role of circular ruffling or its equivalent in three‐dimensional fibroblast‐populated collagen matrices seems to be a rapid reorganization of the actin cytoskeleton in preparation for cell‐matrix interaction. 相似文献
49.
E Laporte-Turpin M-O Marcoux I Claudet E Grouteau P Micheau S Fédérici C Alberge M-F Prère 《Archives de pédiatrie》2006,13(5):449-452
Staphylococcal necrotizing pneumonia producing the Panton Valentine leukotoxin (PVL) has been described for many years. The french reference center for staphylococcal toxaemia defined it with precision in 1999. A 10-year-old child, died in 36 hours from respiratory distress and shock. Staphylococcal pneumonia was suspected then confirmed: S. Aureus producing PVL was isolated in lung, blood and articulations. 相似文献
50.
A study of the interaction of alcohol drinking and tobacco smoking among French cases of laryngeal cancer. 总被引:3,自引:0,他引:3
P Guénel J F Chastang D Luce A Leclerc J Brugère 《Journal of epidemiology and community health》1988,42(4):350-354
Laryngeal cancer represents an important cause of cancer in France, and the individual effects of alcohol and tobacco on this cancer site are well known. However the problem of the interaction between these agents is less extensively documented, and the role of the high consumptions of alcohol has not been studied frequently. A case-control analysis was undertaken to investigate the joint effect of alcohol and tobacco by comparing 197 glottic and 214 supraglottic cancer cases to 4135 controls representative of the French general population. Heavy drinkers were available from the two groups of cases, the highest alcohol category being equivalent to a consumption of more than 2 litres of wine per day. The relative risks estimated for heavy drinkers and smokers were high, and the results indicated an even stronger effect of alcohol drinking and tobacco smoking on the upper part of the laryngeal region. Additive and multiplicative models were fitted to the data. The multiplicative hypothesis was found to be the most appropriate, implying that the risks associated with alcohol and tobacco multiply when the exposures occur simultaneously. The public health implications of this result and the contribution of heavy drinkers and smokers to the frequency of upper respiratory and digestive tract cancers are discussed. 相似文献