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141.
Ohta T Fukuda M Arima K Kawamoto H Hashizume R Arimura T Yamaguchi S 《Breast cancer (Tokyo, Japan)》1997,4(1):17-24
Cyclins and cyclin-dependent kinases may reflect the status of cell proliferation in cancer tissues. The authors sought to
determine whether cdc2 and cyclin D1 are expressed in breast cancer and are useful as prognostic factors. Accumulation of
cdc2 and cyclin D1 proteins was examined in 88 cases of breast cancer using immunoblotting techniques and correlations with
clinicopathological factors and prognoses were investigated. Cdc2 and cyclin D1 proteins were observed in 27.3% and 75.0%
of breast cancers studied, respectively. The incidence of lymph node metastasis was significantly high in cdc2/cyclin D1-double
positive group and low in double negative group. On the other hand, the incidence of estrogen receptor (ER) negative cases
was significantly higher in the cdc2-positive/cyclin D1-negative group. Relapse-free survival times of cdc2-positive cases
were significantly shorter than those of cdc2-negative cases. The relapse-free survival times of cyclin D1-positive cases
also tended to be poorer than those of cyclin D1-negative cases. Multivariate analyses revealed cdc2 as the second most significant
of the prognostic variables, following lymph node status. The three-year relapse-free survival rate of cdc2/cyclin D1-double
positive cases was 58.9%, whereas that of cdc2/cyclin D1-double negative cases was 100%. Cdc2 and cyclin D1 represent the
status of cell proliferation in breast cancer, and may be useful in breast cancer assessment. 相似文献
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143.
Shuji Kaneko Nobumichi Yada Koichiro Fukuda Masanobu Kikuwaka Akinori Akaike Masamichi Satoh 《British journal of pharmacology》1997,121(4):806-812
- Desensitization of μ- and κ-opioid receptor-mediated inhibition of voltage-dependent Ca2+ channels was studied in a Xenopus oocyte translation system.
- In the oocytes coexpressing κ-opioid receptors with N- or Q-type Ca2+ channel α1 and β subunits, the κ-agonist, U50488H, inhibited both neuronal Ca2+ channel current responses in a pertussis toxin-sensitive manner and the inhibition was reduced by prolonged agonist exposure.
- More than 10 min was required to halve the inhibition of Q-type channels by the κ-agonist. However, the half-life for the inhibition of N-type channels was only 6±1 min. In addition, in the oocytes coexpressing μ-opioid receptors with N-type or Q-type channels, the uncoupling rate of the μ-receptor-mediated inhibition of N-channels was also faster than that of Q-type channels.
- In the oocytes coexpressing both μ- and κ-receptors with N-type channels, stimulation of either receptor resulted in a cross-desensitization of the subsequent response to the other agonist. Treatment of oocytes with either H-8 (100 μM), staurosporine (400 nM), okadaic acid (200 nM), phorbol myristate acetate (5 nM) or forskolin (50 μM) plus phosphodiesterase inhibitor did not affect either the desensitization or the agonist-evoked inhibition of Ca2+ channels.
- These results suggest that the rate of rapid desensitization is dependent on the α1 subtype of the neuronal Ca2+ channel, and that a common phosphorylation-independent mechanism underlies the heterologous desensitization between opioid receptor subtypes.
144.
145.
Studies of the effects of the chelating agent, calcium acetylamino propylidene diphosphonic acid (Ca-APDA), on the removal of radioactive strontium with two administration modalities were carried out in rats. The parenteral (intraperitoneal) administration of 150, 300, or 600 mg kg(-1) Ca-APDA was carried out for 3 d, 10 min after exposure of the animals to the strontium injection. On the first day post-treatment, the retention of strontium in the whole body decreased to 90.1%, 83.9%, and 35.1% that of the control level, respectively. The strontium deposited in femur of 600 mg kg(-1) Ca-APDA group was lowered to 28.4% of the control value. A single oral dose of 600 mg kg(-1) Ca-APDA administered simultaneously with, or 10 min after, oral administration of strontium, radionuclide retention in the whole body was reduced after 1 d to 42.9% and 31.9% of the control, respectively; meanwhile the strontium deposited in the femur was reduced to 16.9% and 29.3% of the control. In conclusion, the results indicate the efficacy of the new agent, Ca-APDA, to remove radioactive strontium from the body, or to inhibit the strontium intestinal absorption, in radio-strontium contaminated individuals. 相似文献
146.
Ruhul AM Fukuda H Nakajima K Takatorige T Tatara K 《Environmental health and preventive medicine》1999,4(2):65-70
Health is one of the basic requirements for improvement in the quality of life. Since Bangladesh became independent, a policy
for providing essential minimum health care to all has been actively pursued.
An overview of Public Health Services in Bangladesh is presented in terms of: (1) a profile of the country, (2) an overview
of public health, (3) medical care, and (4) environmental health. Under each of these headings observations are included on
recent trends based upon relevant data and information.
Finally the authors describe the importance of (1) promotion of health care and planning at the national, divisional, local,
and community levels, (2) promotion of medical services at all levels, and (3) effective decentralization of health services
to enhance the services of health facilities. 相似文献
147.
We present a patient with pancreatoblastoma along with a discussion of various cross-sectional imaging features. The tumor was a large multilocular cystic mass with solid components in the left retroperitoneal space. There were fine internal echoes on ultrasonography, and the signal intensity was high on both T1- and T2-weighted MR images in most of the locules, suggesting the presence of hemorrhagic debris. Among the various retroperitoneal organs displaced by the tumor, only the pancreatic tail was inseparable from the mass, suggesting that the pancreatic tail was the origin of the tumor. Pancreatoblastoma should be included in the differential diagnosis when a large left upper quadrant mass with these imaging features is seen in infants and young children. 相似文献
148.
149.
150.
Optical recording with a voltage-sensitive dye was performed in visual cortical slices of the rat to determine the effect of acetylcholine (ACh) on the spread of excitation. In the presence of ACh, the spread of excitation initiated by stimulation at the white matter/layer VI (WM/VI) was greatly suppressed throughout the cortex, with less suppression in the middle layers. By comparing the effect of ACh with that of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), the fraction of the synaptic component that was sensitive to ACh was evaluated. ACh suppressed approximately 40-50% (maximum 55.8%, n = 11) of the initial synaptic component in the superficial and deep layers. In the middle, however, the effect was weakest and only approximately 20-30% (minimum 20.9%, n = 11) of the initial synaptic component was suppressed. On the basis of histological analysis, the region with the weakest ACh effect extended from upper V to lower II/III. To identify the site of ACh action in terms of pre- versus postsynaptic localization, exogenous glutamate was applied. Because ACh did not suppress the excitation induced by glutamate, the site of the ACh action was indicated to be presynaptic. When layer II/III was stimulated instead of WM/VI, the suppression was uniform throughout the cortex. A muscarinic receptor antagonist, atropine, blocked the suppression by ACh. In conclusion, our results indicate the following two points. First, ACh strongly suppresses intracortical connectivity through presynaptic muscarinic receptors. Secondly, in contrast to the intracortical connection, some group(s) of fibres, possibly thalamocortical afferents that arise from white matter and terminate in the middle cortical layers are suppressed much less by ACh. While ACh has been reported to have confusingly diverse effects, e.g. direct depolarization and hyperpolarization as well as synaptic facilitation and suppression, its effect on the propagation of excitation is very clear; suppression on intracortical connection, leaving thalamocortical inputs rather intact. We postulate that cholinergic innervation enables the afferent input to have a relatively dominant effect in the cortex. 相似文献