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101.
102.
To find antiviral agents, various sulfonamidobenzophenone oximes (II) were synthesized from the appropriate m-sulfonamidobenzophenones by hydroxylamine reaction. The reaction products were generally obtained as syn/anti mixtures which were separable by fractional crystallization. The anti isomer had more potent antipoliovirus activity than the syn isomer. Various sulfonamidobenzamides (III) which were structurally related to II were synthesized by the reactions of amino-substituted benzamides with sulfuryl chloride or amines with (aminosulfonyl)benzoyl chloride. Antiviral activity was examined by the plaque-inhibition test. Compounds 5, 36, and 69 exhibited strong antipicornavirus activity. The structure-activity relationships are discussed.  相似文献   
103.
Monoclonal antibodies directed against human, alpha-atrial natriuretic polypeptide (alpha-ANP; Human, 1-28) were obtained by somatic cell fusion between P3-X63-Ag8.653 myeloma cells and spleen cells from a BALB/c mouse immunized with human, alpha-ANP selectively coupled to keyhole limpet hemocyanin. From the analysis of polyclonal sera with respect to determinant specificity before the fusion, the strategy was primarily used to pick up monoclonal antibody specific for the N-terminal residues of human, alpha-ANP. Screening of antibodies in the hybridoma culture supernatants were performed by binding to iodinated synthetic human, alpha-ANP. Two stable clones producing anti-human, alpha-ANP antibodies, designated 13A1 and 10B1, were obtained by the limiting dilution technique. The ability of ANP(Rat, 1-28) to inhibit binding of 125I-human, alpha-ANP to these antibodies was almost equipotent to ANP(human, 1-28). However, ANP fragments (Human, 7-28) and (18-28) did not compete the binding completely. These results suggest that both 13A1 and 10B1 monoclonal antibodies can specifically recognized N-terminus of human, alpha-ANP, and may be a useful tool to investigate receptor binding of human, alpha-ANP by the antagonizing effect.  相似文献   
104.
The transplacental passage of single intravenous doses of aztreonam (AZT), 1 g or 2 g, was examined in 7 sheep and 14 women in late pregnancy, respectively and the obtained data were analyzed by a two-compartment model. The obtained results were summarized as follows. After single 2 g intravenous doses were given to pregnant sheep, the mean peak level of AZT in maternal blood was 83.79 micrograms/ml and the half-life of the beta-phase was 1.525 hours. After single 1 g intravenous doses were administered to pregnant women, the mean peak level of AZT in blood was 102.62 micrograms/ml and the half-life of beta-phase was 2.128 hours. The peak levels in umbilical venous blood and amniotic fluid were 14.43 micrograms/ml and 11.86 micrograms/ml, respectively.  相似文献   
105.
We performed human leukocyte antigens(HLA)typing for class I antigens on 19 Japanese patients with Fisher's syndrome. We demonstrated a statistically significant association between the disease and the HLA-B39 antigen.  相似文献   
106.
Although apoptosis is considered one of the major mechanisms of CD4+ T cell depletion in HIV-infected patients, the virus-infected cells somehow appear to be protected from apoptosis, which generally occurs in bystander cells. Vpr is an auxiliary HIV-1 protein, which, unlike the other regulatory gene products, is present at high copy number in virus particles. We established stable transfectants of CD4+ T Jurkat cells constitutively expressing low levels of vpr. These clones exhibited cell cycle characteristics similar to those of control-transfected cells. Treatment of control clones with apoptotic stimuli (i.e., cycloheximide/tumor necrosis factor α (TNF-α), anti-Fas antibody, or serum starvation) resulted in a massive cell death by apoptosis. In contrast, all the vpr-expressing clones showed an impressive protection from apoptosis independently of the inducer. Notably, vpr antisense phosphorothioate oligodeoxynucleotides render vpr-expressing cells as susceptible to apoptosis induced by cycloheximide and TNF-α as the control clones. Moreover, the constitutive expression of HIV-1 vpr resulted in the upregulation of bcl-2, an oncogene endowed with antiapoptotic activities, and in the downmodulation of bax, a proapoptotic factor of the bcl-2 family. Altogether, these results suggest that low levels of the endogenous vpr protein can interfere with the physiological turnover of T lymphocytes at early stages of virus infection, thus facilitating HIV persistence and, subsequently, viral spread. This might explain why apoptosis mostly occurs in bystander uninfected cells in AIDS patients.  相似文献   
107.
108.
A 17-year-old girl developed vomiting of sudden onset, followed by a state of confusion that progressed rapidly to coma within one day. Laboratory tests indicated iron deficiency anemia and reactive thrombocytosis, but there was no evidence of coagulopathy. There was no history of medication including the contraceptive pill, either. Emergency CT scan without contrast enhancement showed increased density along the course of the vein of Galen and internal cerebral veins. A repeated CT scan without contrast enhancement carried out 24 hours after the onset of the illness confirmed extensive bilateral hypodensity of the thalami, basal ganglia and adjacent white matter. There was also a prominent spontaneous increase in the density of the deep cerebral venous system. MRI was performed 3 days after the onset of the illness, which showed absence of a flow void in the region of the internal cerebral veins and septal veins on T1-weighed images. T2-weighted images showed low intensity in these veins. At autopsy, the bilateral internal cerebral veins were occluded by fresh thrombosis and hemorrhagic infarction was seen in the bilateral thalami.  相似文献   
109.
To evaluate the malignancy of esophageal cancer, we made a statistical clinicopathological study on 66 patients resected with definite operative and histological findings. The cumulative 5-year survival rate was 26.1%. By Cox's proportional hazard model depth and lymph node metastases were the prognostic factors in "Guide Lines for the Clinical and Pathological Studies on Carcinoma of the Esophagus". New histological factors for quantity idea: 1) depth judged by presence of cancer cells before irradiation; 2) intramural spreading characteristics; 3) volume of tumor measuring the infiltrating area of each layer; 4) distribution of metastatic lymph nodes set up by anatomical restriction and surgical risk; 5) number of metastatic lymph nodes. By analyzing the interaction of these 5 factors, the depth was correlated with the volume and the intramural spreading characteristics. The lymph node metastases were correlated significantly with the volume but not with the depth. The depth and the distribution of metastatic lymph nodes influenced prognosis according to Cox's proportional hazard model. Estimated survival rates of these factors were fitted to actual survival rates respectively. Postsurgical survival and adjuvant therapy may be determined by histological factor analysis.  相似文献   
110.
Three cases (case 1, female, aged 30; case 2, male, aged 32; case 3, male, aged 34) of benign brainstem encephalopathy with truncal ataxia were reported. Two patients had prodromal symptoms Neurological examination revealed truncal ataxia in all cases. As additional neurological signs, anisocoria, mydriasis, nystagmus, ptosis, transient opsoclonus, and facial palsy were seen. There was neither drowsiness nor myoclonus in the three cases. On laboratory examinations, cold agglutination test revealed significant elevation in two cases. The examination of cerebrospinal fluid showed a moderate rise of proteins in one case, but did not revealed pleocytosis in any of the cases. Magnetic resonance imaging of one patient revealed an area of high intensity in the left pontine tegmentum by T2-weighed imaging. The prognosis for all these cases was good, and the reappearance of neurological signs was not present until now. Our cases were different from brainstem encephalitis (Bickerstaff's encephalitis) because of an absence of disturbed consciousness and no pleocytosis in the cerebrospinal fluid. Our cases were also different from "myoclonus-opsoclonus syndrome" because of an absence of myoclonus. We discussed a possibility of a new clinical syndrome which we call "benign brainstem encephalopathy with truncal ataxia".  相似文献   
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