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991.
GABA- and glutamate-mediated synaptic potentials in rat dorsal raphe neurons in vitro 总被引:1,自引:0,他引:1
1. Synaptic potentials were recorded with intracellular electrodes from rat dorsal raphe neurons in a slice preparation. 2. Synaptic potentials were evoked by applying electrical pulses to bipolar stimulating electrodes positioned immediately dorsal to the raphe nucleus; these arose after a latency of 0.5-5 ms and had a duration of 20-200 ms. 3. The synaptic potential was biphasic (at the resting potential) when the recording electrodes contained potassium citrate; a depolarization was followed by a hyperpolarization. The hyperpolarization reversed in polarity at -70 mV and was blocked by bicuculline. 4. The depolarizing synaptic potential was reduced to 50-90% of control by kynurenate (1-2 mM) or 6-cyano-2,3-dihydroxy-7-nitro-quinoxaline (CNQX) (10 microM) and increased in amplitude and duration by magnesium-free solution. 5. In magnesium-free solutions (with CNQX), the depolarizing synaptic potential was blocked by DL-2-amino-5-phosphonovaleric acid (APV, 50 microM). APV also blocked depolarization caused by adding N-methyl-D-aspartate (NMDA) to the superfusion solution. 6. The results indicate that raphe neurons display two synaptic potentials having a duration of 150-200 ms: one that is mediated by GABA and a second that is due to an excitatory amino acid. The component mediated by an excitatory amino acid involves, in part, a receptor of the NMDA type. 相似文献
992.
Z U Khan M D Richardson D W Warnock 《International archives of allergy and applied immunology》1984,73(3):205-211
A range of 6 somatic and culture filtrate antigens of Aspergillus fumigatus were evaluated in a rapid ELISA procedure for anti-A. fumigatus IgG where the component incubation times had been reduced to 10 min. Sera from patients with allergic aspergillosis, patients with suspected allergic aspergillosis, and asthmatic patients with or without A. fumigatus precipitins were tested. For all antigens, levels of anti-A. fumigatus IgG were higher in patients with allergic aspergillosis than in the other 3 groups. Low levels of specific IgG were, however, detected in asthmatic patients who had no precipitins against A. fumigatus. None of the antigen preparations enabled all patients with proven or suspected allergic aspergillosis to be separated from the other 2 groups of asthmatic patients. Positive-negative discrimination in ELISA was achieved by the inclusion of 10 pools of precipitin test-negative sera from the 50 asthmatics without A. fumigatus precipitins. The number of sera that were classed as positive in ELISA ranged from 9 to 15 in the allergic aspergillosis group, depending on the antigen used; in the suspected aspergillosis group, the number of positive reactions ranged from 1 to 8, while in the asthmatics with precipitins, the number ranged from 0 to 2. 相似文献
993.
The effect of vasodilator prostaglandins on polymorphonuclear leukocyte infiltration and vascular injury. 总被引:4,自引:8,他引:4 下载免费PDF全文
Some severe acute inflammatory reactions are characterized by polymorphonuclear leukocyte (PMN) infiltration as well as vascular and tissue damage with hemorrhage. Two types of mediators that may be involved in such reactions are chemotactic factors and prostaglandins. The chemotactic factors can induce PMN infiltration, while some types of prostaglandins cause vasodilatation. We reported previously that injection of soluble, nonphagocytosable chemotactic stimuli, zymosan-activated plasma (ZAP), or C5a des Arg into rabbit skin induced PMN-dependent hemorrhage. Here we investigated whether prostaglandins may modulate the rate of PMN infiltration, measured with 51Cr-labeled leukocytes and the degree of hemorrhage, measured with 59Fe-labeled red cells. Prostaglandin (PG) E1 (0.5 microgram) or E2 (1 microgram) increased ZAP-induced PMN accumulation by 81% and hemorrhage by 400%. A similar potentiation by PGE2 was observed when submaximal concentrations of ZAP were injected. Prostaglandin F2 alpha had no such effect. These results indicate that the degree of PMN infiltration of the tissues may be one factor determining the severity of vascular damage. Furthermore, vasodilatory prostaglandins, generated during neutrophilic inflammatory reactions, may enhance chemotactic-factor-mediated PMN infiltration and increase the extent of vascular injury. 相似文献
994.
Zieliński J Czajkowska-Malinowska M Sankowski Z Kisło A Krawczyk K Skucha W Zalewska A Remiszewski W Kachel T Cynowska B Jedrzejczak M Lichota I Czechowska U Trawińska E Bednarek M 《Pneumonologia i alergologia polska》2000,68(5-6):217-225
COPD is the most frequent chronic lung disease in Poland. The disease is however under-diagnosed, especially at the early stages. The aim of the study was to assess the efficacy of spirometric screening for COPD in middle aged smokers. Informations on causes and symptoms of COPD were disseminated in mass media in 14 large cities. Subject aged over 39 and with smoking history of > 10 packyears were invited for a free spirometry in local chest clinic. However, everyone attending had the spirometry performed. Spirometry was performed according to ATS recommendations. Airway obstruction (AO) was diagnosed when FEV1/FVC < 85% of N and categorised as mild (FEV1 > 70% of N), moderate (FEV1 50-69% of N) or severe (FEV1 < 50% of N). Spirometry was accompanied by an antismoking advice. RESULTS: 12.781 subjects were screened (mean age 52 +/- 12 years, 57% males). In 8.269 subjects who complied with inclusion criteria AO was diagnosed in 29.8% (mild in 10.9%, moderate in 12% and severe in 6.9%). In smokers < 40 years of age and a history of < 10 packyears AO was found in 8.8% (mild in 6.0%, moderate in 1.8% and severe in 1.0%). CONCLUSION: Mass spirometry is an effective and easy method for early detection of COPD. 相似文献
995.
Cytophotometric determination of RNA in various brain structures of hypoxia-adapted and unadapted epilepsy-prone rats at different
times after an epileptic seizure shows much smaller decreases in RNA levels and their much more rapid return to normal in
the adapted than in the unadapted rats. The adaptation to hypoxia produces a marked anticonvulsive effect, and this effect
is enhanced and prolonged considerably by pharmacotherapy.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N
o
2, pp. 120–123, February, 1994 相似文献
996.
AIDS-associated Kaposi''s sarcoma-derived cells in long-term culture express and synthesize smooth muscle alpha-actin. 总被引:5,自引:3,他引:5 下载免费PDF全文
H. A. Weich S. Z. Salahuddin P. Gill S. Nakamura R. C. Gallo J. Folkmann 《The American journal of pathology》1991,139(6):1251-1258
Spindle-shaped cells from Kaposi's sarcoma lesions (AIDS-KS cells) were cultured for long periods in the presence of conditioned medium from activated CD4-positive T cells (HTLV-II infected transformed nonvirus producer) and characterized under in vitro conditions. To investigate a possible vascular origin, AIDS-KS cells were analyzed for the presence of smooth muscle alpha-actin, a differentiation marker for vascular smooth muscle cells. Immunofluorescence studies using a monoclonal antibody for smooth muscle alpha-actin demonstrated positive staining of the AIDS-KS cells (KS-3 and KS-4) but not by endothelial cells or fibroblasts. Northern blot analysis using an oligonucleotide probe unique for human smooth muscle alpha-actin indicated the expression of this gene by AIDS-KS cells. Similar analysis of biopsies from the KS lesion showed that in addition to the staining of smooth muscle cells associated with the blood vessels, the tumor-related spindle cells also stained positively. These cells were also analyzed for the expression of different growth factor genes. The platelet-derived growth factor (PDGF) A-chain gene was expressed at a moderate level. The insulin-like growth factor-1 (IGF-1) and insulin-like growth factor-2 (IGF-2) genes were not overexpressed in relation to control cells. These data suggest that the analyzed AIDS-KS cells may be smooth muscle-like cells and therefore of vascular origin. Based on these results as well as previous reports, we speculate that cells of the immune system may regulate growth of cells in the vascular wall by a novel pathway. 相似文献
997.
The protective effects of disodium cromoglycate (DSCG; Lomudal, Intal) and beclomethasone dipropionate (BDA; Aldecin, Becotide, Beclovent) on the late asthmatic response to allergen challenge (LAR) were investigated in 61 patients with allergic bronchial asthma. The 61 patients developed a total of 83 late asthmatic responses, 35 isolated late responses (ILAR), and 48 dual late responses (DLAR), which is a combination of an immediate response (IDLAR) and a late response (LDLAR). Disodium cromoglycate demonstrated significant protective effects on the LAR (P less than .01), however, the LDLAR as part of the DLAR was decreased by DSCG to a slightly higher degree than the ILAR. The BDA also showed significant protective effects on the LAR (P less than .01), but the ILAR was protected by BDA to a slightly higher degree than the LDLAR as part of the DLAR. The immediate asthmatic response as part of the DLAR was prevented by DSCG significantly (P less than .01) while the BDA was ineffective (P greater than .05). It can be concluded that both DSCG and BDA demonstrated significant effects on the LAR. It is suggested that DSCG should be used as a drug of the first choice to control bronchial asthma with an allergy component where the LAR plays a role. The BDA should be added temporarily at the beginning of the treatment of patients in whom the isolated late asthmatic response plays the predominant role, or of patients in whom the DSCG does not provide full control of the LAR during a certain period, eg, during the peak of the pollen season.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
998.
Identification, sequence analysis and phylogeny of the lef-2 gene of Helicoverpa armigera single-nucleocapsid baculovirus 总被引:6,自引:0,他引:6
999.
Data on the general well-being and premenstrual symptoms of military wives were collected on two occasions one year apart. The women's general well-being and premenstrual symptoms were highly correlated on both occasions, but an even higher correlation was found between the presence of premenstrual symptoms at time 1 and the presence of premenstrual symptoms at time 2. Further analyses revealed that women with higher scores on general well-being and premenstrual symptoms were older and reported fewer cognitive depressive symptoms than women with lower scores on general well-being and premenstrual symptoms. At the one-year follow-up, the women with lower scores on general well-being who complained of premenstrual symptoms were more depressed than those who did not. 相似文献
1000.
J L La? Z Aissaoui C Collyn-d'Hooghe M H Delfau B Grandchamp P Fenaux J P Jouet B Desablens M Deminatti M H Loucheux-Lefebvre 《Cancer Genetics and Cytogenetics》1990,48(2):209-216
We studied two cases of chronic myelogenous leukemia (CML) with unusual variant Philadelphia (Ph) translocation (22;22)(q11;q13). Southern blot analysis showed a chromosomal break in the BCR gene within the 5.8-kilobase (kb) breakpoint cluster region (bcr), between bcr exons 2 and 3 and between bcr exons 3 and 4, respectively. Chimeric bcr-abl mRNA was detected using polymerase chain reaction (PCR) which amplified, according to the respective bcr breakpoints, bcr exon 2-abl exon II and bcr exon 3-abl exon II junction products. These results further support the involvement, even when not cytogenetically detectable, of the 9q34 chromosomal region in all variant Ph translocations and that BCR-ABL gene fusion products are causally involved in the development of Ph positive CML. 相似文献