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2.
A murine monoclonal antibody (MDR3M) (isotype: IgM) reactive with mdr3 gene product was generated by immunizing mice with mdr3 -specific peptide (H2 N-12 WRPTSAEGDFELGISSKQKRKKTKTVKMI41 G-COOH) and hybridizing the primed mouse splenic B cells with X63-Ag8,6.5.3 mouse plasmacytoma cells. MDR3M did not cross-react with mdr1 gene product. This monoclonal antibody may be useful for analyzing the role of mdr3 gene product in cells and tissues. 相似文献
3.
Cytosolic calcium concentration-force relation during contractions in the rabbit femoral artery: time-dependency and stimulus specificity.
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1. By use of front-surface fluorometry with fura-2-loaded rabbit femoral arterial strips, both the cytosolic Ca2+ concentration ([Ca2+]i) and force were simultaneously monitored. By utilizing the [Ca2+]i-force curves, we were thus able to examine the temporal changes in the relationships between [Ca2+]i and force ([Ca2+]i-force relationship) during contractions induced by a high external K+ solution, noradrenaline (NA) and 5-hydroxytryptamine (5-HT). 2. The 'basic' [Ca2+]i-force relationship of the Ca(2+)-induced contractions was obtained by the cumulative applications of extracellular Ca2+ (0-10 mM) during 118 mM K(+)-depolarization (Ca(2+)-contractions). 3. When each vascular strip was exposed to high external K+ (30 mM K(+)-118 mM K+) solutions, the [Ca2+]i abruptly increased until it reached a peak, and then slightly decreased and eventually reached a steady-state level. The force also rapidly rose to reach a maximum plateau level. The changes in [Ca2+]i were more rapid than those in the force. Thus, the [Ca2+]i-force curves observed during the contractions induced by high+ (30 mM-118 mM) solutions showed a counter-clockwise rotation, over time. The entire curve shifted to the right, in a concentration-dependent manner, as compared with the line of the 'basic' [Ca2+]i-force relationship of the Ca(2+)-contraction. However, the [Ca2+]i-force relationship of the steady-state of contractions induced by the single dose applications of high K+ (30 mM-118 mM) overlapped with the line of the 'basic' [Ca2+]i-force relationship of Ca(2+)-contractions. 4. As references, the levels of [Ca2+]i and the force at rest (without stimulation) and at the steady-state of the contractions induced by a single dose application of 118 mM K+ solution were designated as 0% and 100%, respectively. When the vascular strips were exposed to NA (10(-5) M) and to 5-HT (10(-4) M), the [Ca2+]i abruptly rose, and reached a peak (107.1 +/- 5.8%) and 101.3 +/- 2.8%, respectively) after 1 min and 2 min, respectively (the [Ca2+]i-rising phase), and thereafter declined with a similar time course (the [Ca2+]i-declining phase) until reaching a low steady level (the steady-state phase). The force induced by 10(-5) M NA and 10(-4) M 5-HT reached a peak at 4 min (129%) and at 2 min (115%), respectively, and thereafter gradually declined. In contrast to the similarity in the [Ca2+]i transient between NA and 5-HT, the force induced by NA declined more slowly and reached higher steady levels than that seen with 5-HT.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
4.
Isamu Narabayshi Toru Suematsu Chieko Suematsu 《European journal of nuclear medicine and molecular imaging》1986,12(7):329-332
Ventilation and perfusion SPECT images during tidal breathing were studied in 15 cases of lung cancer using 81mKr gas and 99mTc-microspheres. Furthermore, functional images of V/Q ratio and Q/V ratio were prepared, and their clinical significance is descussed with reference to general lung function. There was a decreas in %VC and %FEV 1.0in 7 of 15 cases, and an increase of AaDo2 in the blood gas analysis in 12 of 15 cases. Both planar and SPECT images showed ventilation and perfusion abnormalities in all 15 cases. Of these, 12 patients showed matched ventilation and perfusion defects, 2 patients a dead-space effect and 1 patient a shunt effect. In comparing planar and SPECT images, depiction of ventilation and perfusion impairments were equally clear in 11 cases, but in 3, showing a lobar or segmental defect with a shunt effect, the SPECT images were superior. In a patient with markedly impaired function of the affected lung, the remaining function could not be depicted by SPECT. From the above, it seems that better information can be obtained for understanding the ventilation and perfusion states of lung cancer by adding the SPECT images to the planar image. 相似文献
5.
Mitsuo Miyazawa Takahiro Torii Yasuko Toshimitsu Katsuya Okada Isamu Koyama Yoshito Ikada 《American journal of transplantation》2005,5(6):1541-1547
The aim of this study was to fabricate an artificial bile duct for the development of a new treatment for biliary diseases. Eighteen hybrid pigs were implanted with a bile duct organoid unit (BDOU) made of a bioabsorbable polymer. Twelve of the transplanted BDOUs had been seeded with autologous bone marrow cells (BMCs) in advance. Six animals, the controls, were grafted with the scaffold alone with no BMCs seeded. The common bile duct was cut, the hepatic cut end of the native common bile duct was anastomosed to the BDOU and the other end was anastomosed to the duodenum. The controls underwent a similar operation. The neo-bile duct was removed at pre-determined time points and investigated histologically. All 18 recipient pigs survived until their sacrifice at 6 weeks, 10 weeks or 6 months. Histological examination revealed incomplete epithelialization of the neo-bile duct at 6 weeks and 10 weeks after transplantation. At 6 months, the organoid exhibited a morphology almost identical to that of the native common bile duct. No differences were found between the controls and BMC-seeded pigs. These results show that the artificial bile duct thus fabricated can serve as a substitute for the native bile duct. 相似文献
6.
This study was designed to investigate the effect of morphine on formalin-induced nociceptive responses in streptozotocin (STZ) induced-diabetic mice, noninsulin-dependent genetically diabetic db/db mice and their respective controls (ddY and +/+). In nondiabetic (ddY and +/+) mice, morphine (1–10 mg/kg, PO) dose dependently attenuated the biphasic nociceptive responses induced by SC injection of formalin to the hindpaw, demonstrating equipotency on both the first and second phases. Para-chlorophenylalanine (800 mg/kg × 2, PO) and pindolol (1 mg/kg, IP) reduced the effect of morphine on the first phase, sulpiride (10 mg/kg, IP) abolished the effect on both phases, while ketanserin (1 mg/kg, IP) had no effect. In STZ (200 mg/kg, IP)-diabetic mice, morphine weakly attenuated the nociception in comparison to control ddY mice, whereas it had comparable effects in both the first and second phases of control +/+ mice and db/db mice. The serotonergic agonist, meta-chlorophenylpiperazine (0.32–3.2 mg/kg, PO), dose dependently attenuated the biphasic nociceptive responses to formalin in both phases of diabetic mice; however, FR64822, a dopaminergic compound (0.1–10 mg/kg, PO), had little effect. We speculate that activation of both dopaminergic (DA)- and serotonergic-mediated mechanisms are potentially responsible for the effect of morphine on the first phase, while the DA-mediated effect is involved in the second phase. The DA-mediated mechanism, but not the serotonin-mediated one, appears to be altered in both STZ-diabetic and db/db mice. These results suggest that the attenuated effects of morphine might be due to a dopaminergic dysfunction in STZ mice, and that there might be other mechanisms compensating for this attenuation of dopaminergic function in db/db mice. 相似文献
7.
The effect of halothane and enflurane on tracheal tone were studied in 21 patients during the induction of anesthesia. Endotracheal tube cuff pressure was used to measure tracheal tone. Anesthesia, maintained by nitrous oxide 70% in oxygen, was supplimented with succinylcholine drip infusion to immobilize the patient. Ventilation was controlled by a Volume-preset ventilator. In the halothane group, the initial cuff pressure was 14.8 ± 1.3 (mean ± SE) cmH2O but 10min after 0.15mg/kg of pancuronium injection, it increased to 21.7 ± 2.3cmH2O (control). Ten min after inhalation of 0.75% of halothane, cuff pressure decreased to 14.7 ± 2.3cmH2O (34 ± 11% decrease from the control value). In the enflurane group, the initial cuff pressure was 17.6 ± 1.8cmH2O and it increased to 21.0 ± 1.7cmH2O (control) 10min after pancuronium injection. Ten min after 1.7% of enflurane inhalation, cuff pressure decreased to 17.1 ± 2.3cmH2O (23.9 ± 6% decrease from the control value). Halothane and enflurane produced similar tracheal dilatation in healthy individuals.(Yasuda I, Irimada M, Hirano T et al.: Tracheal dilatation by halothane and enflurane in man. J Anesth 2: 46–49, 1988) 相似文献
8.
Streptococcus sobrinus antigens that react to salivary antibodies induced by tonsillar application of formalin-killed S. sobrinus in rabbits
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We previously found that tonsillar application of antigen induces a strong antibody response to Streptococcus sobrinus in saliva and blood plasma. Rabbits immunized against S. sobrinus by tonsillar application were highly resistant to experimental dental caries triggered by oral inoculation of living S. sobrinus organisms with sucrose. In the present study, we examined the reaction of S. sobrinus antigens to the antibodies induced by the tonsillar application of S. sobrinus AHT-k in rabbits and compared them to those antibodies induced by intramuscular injection. In an enzyme-linked immunosorbent assay using ultrasonic fragments from mutans group streptococci, the saliva and blood plasma selectively reacted to S. sobrinus AHT-k (serotype g) and serologically related streptococci (serotypes a, d, and h) in the sixth week after tonsillar application, whereas the blood plasma in the sixth week after intramuscular injection reacted to the unrelated streptococci (serotypes b, c, e, and f) in addition to the aforementioned streptococci. The antibody reactivity induced after tonsillar application was not lost after treatment of the antigen with heat or proteinase digestion, whereas these treatments resulted in a 70% decrease of the antibody reactivity induced by intramuscular injection. The inhibition by haptenic sugars and the decrease in immunoreactivity by heat treatment and proteinase digestion suggested that 80% of the antibodies induced by tonsillar application reacted to saccharides. These saccharide antigens appeared to be involved in a specific reaction with S. sobrinus-specific streptococci and a selective reaction with serologically related streptococci. These antigens are probably involved in anticaries reactions in experimental dental caries. 相似文献
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10.
We have investigated the potential of neurotropic microbes to invade the central nervous system (CNS) via the peripheral nervous system. Herpes simplex virus type 1 (HSV-1) strain KH6 and herpes simplex virus type 2 (HSV-2) strain 186 were found to infect chemosensory neurons in the vomeronasal organ (the pheromone detector) following intranasal inoculation of mice. HSV-1 strain KH6 infection was further transmitted to the accessory olfactory bulb (first relay), the medial amygdala (second relay), and the bed nucleus of the stria terminalis and the ventromedial hypothalamus (third relay). HSV-1 strain KH6 also targeted the olfactory and trigeminal systems. HSV-2 strain 186 predominantly attacked the brainstem including the trigeminal system. While both viruses did not induce apoptosis in infected chemosensory neurons, they did in infected brain tissue. These results suggest that neurotropic viruses can invade the brain by infecting vomeronasal chemosensory neurons and that the restrained induction of apoptosis in the infected neurons may facilitate viral transmission to the CNS. 相似文献