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41.
In order to study the mechanism of GH secretion from somatotroph adenoma cells, we have compared the effect of 12–O-tetradecanoyl phorboi-13-acetate (TPA) with that of growth hormone releasing factor (GRF) on GH secretion from human somatotroph adenoma cells cultured in monolayer. Pituitary adenoma cells were obtained from 13 patients with acromegaly undergoing surgery. On the 7th day of culture, the cells were exposed for 2 h to secretagogues. All 13 adenoma cell cultures (100%) responded to TPA (1·6–16·0 nmol/I) with a two- to six-fold increase in GH release (240·37% Increase of control: mean±SE). The response was detectable within 10 min, and was maximal at 2 h. Phosphollpase C (7·7 mmol/I) also stimulated a two-to ten-fold Increase In GH release in all four adenomas examined (100%). GH release was stimulated by GRF (2·0 nmol/I) in eight out of 12 adenoma cells (67%), but the magnitude of the responses to GRF (60·18% Increase of control: mean ± SE) were much smaller than that of TPA. Five out of 13 adenomas secreted detectable amount of PRL Into the medium and these five adenomas (100%) responded to TPA (16·0 nmol/I) with a two- to six-fold Increase. These observations indicate that the activation of protein kinase C is the consistent stimulator in GH and PRL secretion In human somatotroph adenoma cells. However, It is not determined whether the protein kinase C  相似文献   
42.
Immunohistochemical study of bone GLA protein in primary bone tumors.   总被引:3,自引:0,他引:3  
METHODS. The immunoreactivity of bone GLA protein (BGP) in primary bone tumors, including osteosarcoma, chondrosarcoma, malignant fibrous histiocytoma of bone (MFH), and giant cell tumor of bone (GCT), was investigated with anti-BGP rabbit serum and peroxidase-antiperoxidase complex. RESULTS. As to intracellular localization, BGP antigenicity was detected in 33 of 35 cases of osteosarcoma and 12 of 25 cases of chondrosarcoma. However, there were no positive findings in all 15 cases of MFH or 20 cases of GCT. In chondrosarcoma, the frequency of positively stained cases increased according to pathologic grading (i.e., 3 of 14 cases of Grade 1, 7 of 9 cases of Grade 2, and 2 of 2 cases of Grade 3). Although the multinucleated cells in MFH or GCT were not immunostained, BGP antigenicity was observed in the multinucleated cells of osteosarcoma (12 of 15 cases). In the matrix of osteosarcoma, BGP immunoreactivity of the tumorous osteoid was observed in 28 of 32 cases. However, in the matrices of chondrosarcoma, MFH, and GCT, BGP immunoreactivity was not observed. CONCLUSION. These results suggest that the immunohistochemical study of BGP is useful for the differential diagnosis of bone tumors.  相似文献   
43.
We examined the localization of basic fibroblast growth factor (basic FGF) in the adult rat brain by immunohistochemical and Western blotting analysis using a specific antibody against a synthetic basic FGF fragment (N-terminal 12 residues). The antibody did not cross-react with acidic FGF. Basic FGF-like immunoreactivity was located exclusively in the neuronal elements and had very heterogenous distribution. Immunoreactive cell bodies were observed in the paraventricular, supraoptic and circular nuclei of the hypothalamus. Numerous immunoreactive neuronal processes originating from these basic FGF-positive cells extended lateroventrally and then caudally to the internal layer of the median eminence. In addition, the neurohypophysis contained a significant number of basic FGF-like immunoreactive fibers. Western-blotting analysis revealed that the hypothalamus and the hypophysis contained a main band of basic FGF immunoreactive with an apparent molecular weight of 17 kDa. These results show that the hypothalamo-hypophyseal neuroendocrine pathway contains basic FGF.  相似文献   
44.
Electrochemotherapy is a novel antitumor treatment involving the systemic administration of bleomycin followed by the delivery of electrical pulses to the tumor. The present study investigates the effects of electrochemotherapy on the growth of colon 26 cells inoculated subcutaneously into the backs of BALB/c mice. The mice were divided into the following four experimental groups: 20 that received no further treatment after the inoculation of colon 26 cells (control group); 20 that received 500 μg of bleomycin intraperitoneally 7 and 9 days after the inoculation (BLM group); 20 that received electric pulses to the tumor 7 and 9 days after the inoculation (EP group); and 30 that received electrochemotherapy 7 and 9 days after the inoculation (ECT group). During 28 days of observation, no deaths due to tumor progression occurred in the ECT group, but there were 18 in the control group, 11 in the BLM group, and 18 in the EP group. While weight loss was observed in all groups, it was most remarkable in the control group. Tumor growth was significantly inhibited in the ECT group, compared to the other experimental groups (P<0.01). The results of this study demonstrated that electrochemotherapy significantly inhibited the growth of colon 26 tumors in mice, without causing any remarkable adverse effects.  相似文献   
45.
Lesions in the thalamus or basal ganglia have rarely been reported in acute disseminated encephalomyelitis (ADEM). We experienced 2 cases of ADEM, in which MRI showed lesions in the thalamus or basal ganglia. Case 1, a 4-year-old boy, had gait disturbance, hyperesthesia and hyperreflexia. MRI (T2 weighted image) showed multiple high intensity areas in the right frontal lobe, bilateral parietal lobes and bilateral thalami. Case 2, a 4-year-old girl, complained of gait disturbance following a febrile episode, and displayed hyperreflexia. Several days later, she had visual disturbance of the left eye. MRI (T2 weighted image) revealed multiple high intensity areas in the dentate nucleus of left cerebellum, left occipital lobe, bilateral caudate nuclei, and the anterior part of bilateral lenticular nuclei. In both cases, CT could not demonstrate these lesions. Both of them were treated with corticosteroid and recovered rapidly. They had no recurrence. MRI is useful in diagnosis and follow-up of ADEM and may reveal lesions other than cerebral or cerebellar white matters.  相似文献   
46.
47.
Abstract True incidence of this malformation is probably greater than that reported since the definitive diagnosis has been made at autopsy in most cases. Various hypotheses on the pathogenesis of tracheal agenesis have been proposed but they are still controversial.
In this report, we present a case of tracheal agenesis with a broncho-esophageal fistula and discuss the formal genesis.  相似文献   
48.
Oligonol is produced from the oligomerization of polyphenols (typically proanthocyanidin from a variety of fruits such as lychees, grapes, apples, persimmons, etc.) and contains catechin-type monomers and oligomers of proanthocyanidins. The ability of Oligonol to affect infection-dependent eye inflammation, locomotion and longevity in senescence-accelerated prone mice (SAMP8) (a model of senescence acceleration and geriatric disorders with increased oxidative stress and neuronal deficit) was investigated. Oligonol (60mg/kg) significantly modulated the extent of inflammation scores in the eye of SAMP8 mice. Examination of the mice indicated infection with mouse hepatitis virus and pinworm (Syphacia obvelata) in both males and females and with the intestinal protozoa (trichomonad) in males. A comparison of the two groups (using log-rank test) and the difference in the mean life span between groups (using Student's t-test) indicated significant differences in survival (p=0.043) and the mean life span (p=0.033) in male SAMP8 mice. Oligonol increased the mean life span and this was statistically significant. In the open-field locomotive test, the 7-week-old SAMP8 mice crossed more than 40 partitioned lines in 1min. At 48-week-old control untreated male SAMP8 crossed 2 lines. The Oligonol-treated 48-week-old male SAMP8 mice crossed 17 lines however. The improved locomotive activity was statistically significant even after 36weeks in the Oligonol-treated male SAMP8 but this was not the case throughout the time course of the study in the Oligonol-treated female SAMP8. Thus Oligonol treatment to SAMP8 mice modulated the severity of infection-dependent inflammation, prolonged life-span and significantly improved locomotive activity indicating potential benefit to aging-associated diseases such as Alzheimer's or Parkinson's diseases. This presents potential for further research to define infection-dependent inflammation associated with degenerative conditions and the molecular mechanism of dietary antioxidant protection.  相似文献   
49.
Male F344 rats were treated with lead nitrate and changes inthe expression and induction of P450IA subfamily enzymes anda placental form of glutathione-S-transferase (GST-P) in theliver were assessed by means of a bacterial mutation test, immunoblottingwith a monoclonal antibody reactive to P450IA1/IA2 and anti-GST-Psera and Northern blotting with P450IA2 cDNA as a probe. Treatmentof rats with lead nitrate (20, 50 or 100 µmol/kg bodywt) decreased P450IA2 mRNA and protein in the liver in the dose-dependentfashion and also decreased the microsomal activity for P450IA2-dependentmutagenization of aromatic amines. Pretreatment of rats withlead nitrate suppressed the inductions of both P450IA2 mRNAand protein by an inducer of P450IA subfamily enzymes in theliver. In addition, amount of the induced P450IA2 was decreasedalong with increase in that of the induced GST-P.  相似文献   
50.
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