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991.
992.
H Ono  Y Hasebe  M Satoh  T Nagao  S Ohta  M Hirobe  H Fuduka 《Brain research》1991,564(2):319-322
The antagonistic effects of 4-phenyl-1,2,3,4-tetrahydroisoquinoline (4PTIQ) against S(+)-methamphetamine, phenylethylamine and nomifensine were studied by measurement of spinal monosynaptic reflex potential (MSR). S(+)-Methamphetamine, phenylethylamine and nomifensine enhanced the amplitude of MSR in C1-spinalized rats through release of noradrenaline from the terminals of descending fibers and consequent activation of alpha 1-adrenoceptors. Although 4PTIQ alone did not change the amplitude of the MSR, 4PTIQ inhibited the enhancement of MSR induced by S(+)-methamphetamine and related compounds. The MSR of rats with an intact spinal cord was enhanced by conditioning stimulation of the ipsilateral locus ceruleus. The MSR enhancement produced by the stimulation was blocked by prazosin but unaffected by 4PTIQ, showing that 4PTIQ does not have an alpha 1-blocking action. These results suggest that the antagonistic effects of 4PTIQ on MSR enhancement by S(+)-methamphetamine, phenylethylamine and nomifensine are due to its blocking of noradrenaline release produced by these amphetamine-like agents.  相似文献   
993.
A case of cutaneous mucormycosis in Shanghai, China   总被引:1,自引:0,他引:1  
J J Wang  H Satoh  H Takahashi  A Hasegawa 《Mycoses》1990,33(6):311-315
A 34-year-old female farmer suffered from localized cutaneous mucormycosis for 17 years. At the first admission, the lesion was a dull red plaque, about 7 x 9 cm in size with ulcerations, surrounded by some nodules on the dorsum of her right hand. General examination did not reveal abnormal findings except the skin lesion. Direct examination of skin scrapings in 10% KOH revealed broad, sparsely septate, branching hyphae. Histopathology showed many intradermal granulomata and microabscesses as well as mycelial elements comprising broad, distorted, ribbon-like strands. Some of them were phagocytized by multi-nucleated giant cells. Cultures revealed rapidly growing yellow colonies on Sabouraud dextrose agar medium at 25 degrees C. Sporangiophores branched in sympodia and the sporangia were globose, 35-60 microns in diameter. Their walls were deliquescent, but some of them were rather persistent. Columellae were mostly globose, 12-17 microns in diameter, up to 35 microns with collars. Sporangiospores were mainly ellipsoidal, 1.5-2.5 x 3-5 microns in size, but sometimes highly variable in size and shape. The maximum growth temperature of the isolate was 37 degrees C. The pathogenic organism isolated was tentatively identified as Mucor lusitanicus, which, as far as we know, has not been reported as a causative agent of cutaneous mucormycosis.  相似文献   
994.
We investigated the expression of intercellular adhesion molecule-1 (ICAM-1) on primary cultures of human adult oligodendrocytes and astrocytes. Under unstimulated conditions, low levels of ICAM-1 immunoreactivity were identified on both oligodendrocytes (less than 50%) and astrocytes (less than 30%). After 48 hours' exposure to immune mediators, such as culture supernatant of phytohemagglutinin (PHA)-stimulated lymphocytes, interferon gamma (IFN-gamma; 1,000 U/ml), tumor necrosis factor alpha (TNF-alpha; 2,000 U/ml), interleukin-1 alpha (IL-1 alpha; 1,000 U/ml) and lipopolysaccharide (LPS; 50 micrograms/ml), ICAM-1 expression on both cell types was markedly increased in terms of intensity and cell numbers. IFN-gamma and culture supernatant of PHA-stimulated lymphocytes were the most potent inducers of ICAM-1 among the mediators tested, while TNF-alpha, IL-alpha and LPS were less effective, although variations were observed among cultures derived from different donors. Cytokine-induced expression of ICAM-1 on glial cells may play a role in mediating lymphocyte-glial cell interactions at sites of inflammation in the central nervous system.  相似文献   
995.
The syntheses and biological activities of new 7-beta-[(Z)-2-(2-amino-4-thiazolyl)-2-hydroxy-iminoacetamido]-3-(1 ,3- dithiolan-2-yl)-3-cephem-4-carboxylic acid (YM-22508, 1a), 7-beta-[(Z)-2-(2-amino-4-thiazolyl)-2- methoxyiminoacetamido]-3-(1,3-dithiolan-2-yl)-3-cephem-4-carboxyli c acid (YM-16457, 1d) and their prodrug-type esters are described. Among them, YM-22561 (1c), the 1-acetoxyethyl ester of 1a, showed good in vivo efficacy in mice against infections of Staphylococcus aureus Smith, Streptococcus pyogenes S 23 and Escherichia coli NY-17 and a long plasma T1/2 in mice.  相似文献   
996.
We performed both free and albumin-bound bilirubin removal therapy using the Evaflux-2A and evaluated its clinical effects. The removal rates of total bilirubin in the first and second sessions were 31.4%, and 31.0%, respectively. Our clinical data suggested that plasma exchange using Evaflux-2A and an albumin-added electrolyte solution as the substitute fluid was useful in the treatment of hyperbilirubinemia.  相似文献   
997.
Creatine kinase (CK) has three forms of isozymes; CK-BB, CK-MB, and CK-MM. In adult rats they show a specific tissue distribution: the BB form in the brain, the MB form in the heart, and the MM form in skeletal muscle. In embryonic skeletal muscles only the BB and MB forms are found. Adult slow-twitch muscles contain more fetal type creatine kinase (CK-B) than do fast-twitch muscles. In the present experiment the effect of denervation and reinnervation on the CK-B concentration was investigated in rat fast (extensor digitorum longus)- and slow (soleus)-twitch muscles by a highly sensitive immunoassay. Denervation of these muscles produced a progressive increase in CK-B concentration in both muscles. When the sciatic nerve was cut and immediately sutured, the CK-B concentration in both muscles showed a gradual reduction after an initial increase. By the 34th postoperative week the CK-B concentration in the soleus was about one-half that of the contralateral control, whereas that in the extensor digitorum longus was nearly normal. After cross union of the nerves innervating the muscles, the CK-B concentration in the soleus was reduced at 35 weeks to about one-half normal, but that in the extensor digitorum longus was always higher than the control value. After self-reunion of the nerves, the CK-B concentration at the 20th week was approximately normal in the extensor digitorum longus and significantly increased in the soleus. We suggest that the motoneurons normally innervating the extensor digitorum longus have a greater capability in suppressing the production of CK-B than do the soleus motoneurons.  相似文献   
998.
We have investigated regulatory cell abnormalities in patients with autoimmune thyroid diseases through in vitro thyroglobulin (Tg) specific helper factor production. Helper activities were measured in the mice spleen cell assays, using hapten-carrier system. Peripheral blood leukocytes (PBL) from 5 out of 6 patients produced the Tg specific helper factor not only when they were stimulated in vitro with Tg but also when they were not stimulated. On the contrary, normal PBL did not produce the factor when they were not stimulated in vitro. However, 3 out of 5 normal PBL did produce the factor when they were stimulated in vitro with Tg. From several lines of studies, this helper factor was specific for Tg in its production and action. From these results it is concluded that (a) Tg specific helper T cells are already activated in vivo in patients with autoimmune thyroid diseases, indicating the presence of immunoregulatory abnormalities in these patients, and that (b) normal PBL have a potential to produce this helper factor when they are appropriately stimulated.  相似文献   
999.
A desire for death and requests to hasten death are major topics in recent medical literature. The aim of this study was to clarify the bereaved family-reported incidence and reasons for desiring death and requests to hasten death during the whole course of terminally ill cancer patients receiving specialized palliative care in Japan. A nationwide questionnaire survey of 500 primary caregivers yielded a total of 290 responses (effective response rate, 62%). Sixty-two (21%) families reported that the patients had expressed a desire to die, and 29 (10%) families reported that the patients had requested that death be hastened. The major reasons for desiring death and requests to hasten death were: burden on others, dependency, meaninglessness, unable to pursue pleasurable activities, general malaise, pain, dyspnea, concerns about future distress, and wish to control the time of death. No intolerable physical symptoms were reported in 32% and 28% of the patients who desired death and those who requested to hasten death, respectively. Concerns about future distress and wishes to control the time of death were significantly more likely to be listed as major reasons for desiring death in patients who requested that death be hastened than those who did not. A desire for death and requests to hasten death are not uncommon in terminally ill cancer patients receiving specialized inpatient palliative care in Japan. More intensive strategies for general malaise, pain, and dyspnea near the end of life, and for feelings of being a burden, meaninglessness, and concerns about future distress would alleviate the serious suffering of patients with a desire for death. However, some patients with a strong wish to control the time of death might not receive benefit from conventional palliative care.  相似文献   
1000.
The level of endogenous prostacyclin (PGI2), prostaglandin E2 (PGE2) and thromboxane A2 (TXA2) in rat gastric mucosa was determined by radioimmunoassay to examine whether gefarnate, an antiulcer agent, maintained the endogenous prostaglandin (PG) level in rats subjected to water-immersion stress. Seven-hr immersion induced gastric lesions and a marked reduction in PGI2 and PGE2. When gefarnate was injected subcutaneously before stress exposure, the mean ulcer index was reduced and the PGI2 and PGE2 levels were maintained. Our results suggest that the reduction of endogenous PGI2 and PGE2 is a major factor in water-immersion-induced ulcers in rats, and that gefarnate inhibits this ulcer formation by inhibiting a reduction in those PGs induced by water-immersion stress.  相似文献   
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