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121.
A Sakai K Sasaki H Mizusawa M Ishidate 《Teratogenesis, carcinogenesis, and mutagenesis》1990,10(4):333-340
Quercetin was examined for the effects on the two-stage chemical transformation of BALB/3T3 cells. Quercetin showed initiating action to induce transformation in the cells which were treated with quercetin and subsequently with 0.49 microM 12-O-tetradecanoyl-phorbol-13-acetate (TPA). Both the proportion of dishes with transformed foci and the average number of foci per dish increased with the concentration of quercetin (15-45 microM). However, initiating treatment with quercetin did not induce transformation without subsequent TPA treatment. Quercetin inhibited the promotion caused by 0.49 microM TPA in the transformation initiated by 1.9 microM 2-methylcholanthrene (MCA). The inhibitory effect of 30 microM quercetin was 56% in the number of foci per dish. Thus quercetin was found to have initiating effect on the transformation of BALB/3T3 cells, but to restrain the promotion by TPA. 相似文献
122.
123.
M Sasaki K Ono N Kawahara H Tsutsumi T Aruga H Toyooka K Mii M Tsuzuki K Takakura 《No shinkei geka. Neurological surgery》1984,12(6):673-678
Head injury patients often complicate facial and/or multiple injuries other than cranio-cerebral insults and perplex the emergency staffs. The authors used Brighton epistaxis balloon for such patients with massive nasal bleeding and reported the utility of the balloon not only in such state of emergency but also for a few days to control the hemorrhage mostly caused by craniobasal fractures or rupture of the adjacent vessels. One hundred and twenty-nine patients were transported and hospitalized in Department of Emergency Medicine, University of Tokyo Hospital, Tokyo, Japan during the period from October, 1981 to January, 1983. Nasal bleeding was noted in 29 cases of them and the balloon was used in 10 cases, who were from 19 to 76 years of age, all males and suffered from basal fractures or craniofacial injuries. Six cases of them were also accompanied with fractures in the extremities or pelvis, hemopneumothorax and/or intra-abdominal bleeding and could not but put on "Military anti-shock trousers" for the management of hypovolemic shock, hence the nasal bleeding should be managed immediately in the emergency room. In these situations the balloon was inserted into both nasal cavities in all the patients, to control successfully the nasal hemorrhages one of which contaminated cerebrospinal fluid and three of which were sure to be pulsatile due to arterial injury. The Brighton epistaxis balloon is to be removed within twelve or twenty-four hours, but in the authors' cases the mean duration for the hemostasis was 58.9 hours for 6 survivors and 49.6 hours for all 10 cases.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
124.
Background/PurposeWe examined the effects and mechanisms of rikkunshito (RKT) and hangeshashinto (HST) on cisplatin-induced mucosal injuries in the rat small bowel.MethodsJuvenile rats were divided into 6 groups: sham control, cisplatin injection without kampo medicines, and cisplatin injection with oral administration of low and high doses of RKT (1000 mg/kg and 2000 mg/kg) and HST (500 mg/kg and 1000 mg/kg). Fecal condition, intestinal morphological changes, enterocyte proliferation, and enterocyte apoptosis were assessed.ResultsDiarrhea and atrophy of ileal villi observed in the cisplatin group were significantly improved in all kampo groups. Injury scores of the jejunum were significantly lower with RKT (2000 mg/kg) and HST (500 and 1000 mg/kg) than with cisplatin, and those of the ileum were significantly lower with HST (500 and 1000 mg/kg) than with cisplatin. Enterocyte proliferation of the jejunum was significantly increased with RKT (2000 mg/kg) and HST (500 mg/kg) compared with cisplatin, and those of the ileum were significantly increased in all kampo groups compared with the cisplatin group. Jejunal and ileal apoptosis following cisplatin administration was significantly inhibited by HST.ConclusionsRKT and HST prevented cisplatin-induced intestinal mucosal injury with increasing proliferation of intestinal epithelial cells. HST also attenuated cisplatin-induced crypt cell apoptosis. 相似文献
125.
126.
127.
Effects of mechanical stretch on membrane currents of single ventricular myocytes of guinea-pig heart. 总被引:10,自引:0,他引:10
A technique to record whole cell membrane current during stretching single cardiac myocytes was developed. Ventricular myocytes were dissociated by treating guinea-pig hearts with collagenase. One end of the cell was fixed either to a microglasstool tip or to a glass plate, while the other end was attached either to a microglasstool tip or to a suction pipette, which was mounted on a micromanipulator. A time-independent current showing a reversal potential of -15 +/- 4 mV (n = 7) was activated when the myocytes were stretched more than 20% of the length between two fixed point. The current gradually relaxed during the maintained stretch, and disappeared on releasing the stretch. We failed to detect any consistent change in either the L-type Ca2+ current or the inward rectifier K+ current. For comparison, current changes induced by inflating the cell using a hypo-osmotic solution were recorded. The inflation was not accompanied by any change in the time-independent current. Instead, the delayed rectifier K+ current was increased to 170 +/- 48% control by the 70% hypo-osmotic solution. Thus, the effect of mechanical stretch on the time-independent current is different from those of hypo-osmotic cell inflation. The stretch-induced time-independent current is compared with reported current changes induced by the intracellular microinjection of Ca2+. 相似文献
128.
To obtain objective information about bladder cancer, we measured the mean nuclear volume of bladder cancer cells by using the "Point Sampled Intercepts" method, which was published by Gundersen et al. Thirty one cases of bladder cancer were selected and divided into 2 groups: group A; no recurrence over 3 years after initial TUR (12 cases), group B; cystectomy or cancer death (19 cases). Estimated mean nuclear volume was significantly smaller in group A than in group B. It is suggested that estimation of the mean nuclear volume by this stereological method may provide objective information for predicting the prognosis of patients with bladder cancers. Further studies in additional patients are required to substantiate the predictive potential of this method. 相似文献
129.
O. Sasaki S. Asawa S. Katsuno S. Usami K. Taguchi 《European archives of oto-rhino-laryngology》2000,257(9):490-492
Vestibular evoked myogenic potentials (VEMP) occurring after click stimulation in cervical muscles are thought to be a polysynaptic
response of otolith-vestibular nerve origin. In optokinetic after-nystagmus (OKAN) the direction of after-nystagmus changes
and slow-phase velocity decreases with head tilt. This phenomenon may be an otolith response to the direction of gravity.
We assumed that intense clicks might have some influence on OKAN via the otolith-vestibular nerve. Twelve normal subjects
who showed VEMP at 75 dB normal hearing level (nHL) clicks were examined. The OKAN was recorded under four conditions: right
monaural, left monaural and binaural stimulation by 75 dB nHL clicks, and absence of click stimulation. Horizontal optokinetic
stimulation was applied using stepwise increasing speeds from 30 deg/s to 90 deg/s. Two seconds before the stimulus ended,
clicks were sounded. The slow-phase velocity of the recorded electro-nystagmography was manually measured. There was no effect
on OKAN with unilateral stimulation but binaural stimulation suppressed it. These results suggest that a velocity storage
integrator is influenced by intense clicks via the otolithic area.
Received: 17 November 1999 / Accepted: 30 May 2000 相似文献
130.
Tadao Uchibayashi Soo-Woong Lee Kazuto Kunimi Mitsuo Chkawa Yoshio Endo Mika Noguchi Takuma Sasaki 《Cancer chemotherapy and pharmacology》1994,35(Z1):S84-S87
Cultivated T24 cells derived from a human bladder cancer were inoculated into the chorioallantoic membrane vein of chick embryos. Hyperthermic treatment was performed following injection of anticancer agents 3 days after the inoculation of the T24 cells. DNA samples were obtained from the livers of the chick embryos, and the polymerase chain reaction technique was used to amplify a DNA fragment specific to the human -globin gene. The Southern hybridization method was used to evaluate the inhibitory effects of anticancer agents in combination with/without hyperthermia on T24 cells metastasized to the liver. The hyperthermia exerted an inhibitory effect on the growth of the T24 cells in the livers of the chick embryos, and this was dependent on the thermal dose. The antitumor effects of hyperthermia performed at 42.5° C for 20 min and at 43.0° C for 10 min were evidenced by 69.2% an 82.0% inhibition of the growth of the metastasized T24 cells, respectively, as compared with the growth of untreated T24 cell. Hyperthermia performed at 42.5° C for 10 min alone produced 26.7% tumor growth inhibition, and these conditions for hyperthermia were subsequently used as a criterion for evaluating the effects of its combination with various anticancer agents. Adriamycin (20 g/egg) alone, mitomycin C (10 g/egg) alone, carboplatin (10 g/egg) alone, and cisplatin (10 g/egg) alone produced 13.5%, 58.9%, 27.3%, and 29.1% tumor growth inhibition, respectively. Adriamycin and mitomycin C applied in combination with hyperthermia showed additive inhibitory effects on the growth of the metastasized T24 cells in this chick embryo model. 相似文献