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41.
Susanne K. Kjaer Claus Dahl Gerda Engholm Johannes E. Bock Elsebeth Lynge Ole M. Jensen 《Cancer causes & control : CCC》1992,3(4):339-348
Sexual, reproductive and venereal risk factors for cervical neoplasia were investigated in a population-based case-control study of 586 women with histologically verified, cervical squamous-cell carcinoma in situ, and 59 women with invasive squamous-cell cervical cancer, diagnosed from 1985 to 1986 in Copenhagen. Cases were identified from the computerized Danish Cancer Registry. An age-stratified control group (n=614) was drawn at random from the female population in the study area by means of the Danish Central Population Register. A structured questionnaire was mailed to cases as well as controls. Increasing number of sexual partners exerted a significant effect on the risk both for carcinoma in situ, and invasive cancer, independently of age at first intercourse and other potential confounders. Conversely, the association with early age at first intercourse became statistically insignificant after allowance for other risk factors, although an increasing risk was still observed with decreasing age at sexual debut. Early age at first episode with genital warts was a significant risk factor for carcinoma in situ, perhaps indicating a possible increased susceptibility of the cervix epithelium during adolescence. A history of genital warts was a good predictor of risk for carcinoma in situ, whereas a history of previous gonorrhea was associated with an increased risk for invasive carcinoma. Women with multiple births had a significantly increased adjusted risk, especially for carcinoma in situ, although some association was also observed with invasive cervical cancer. The study supports the hypothesis of cervical neoplasia being a sexually transmitted disease, and that carcinoma in situ and invasive cervical carcinoma, to a high degree, have similar patterns of risk factors.Drs Kjaer, Engholm, and Lynge are with the Danish Cancer Registry. Dr Dahl is with the Department of Surgery, Slagelse Hospital, Denmark. Dr Bock is with the Department of Gynecology, Rigshospitalet, Copenhagen, Denmark. Dr Jensen, formerly with the Danish Cancer Registry, is deceased. Address correspondence to Dr Kjaer, Danish Cancer Registry, Institute of Cancer Epidemiology, Danish Cancer Society, Rosenvengets Hovedvej 35, Box 839, Copenhagen. Denmark. The Danish Cancer Society supported this study through grants. 相似文献
42.
D J Deziel D M Jensen J H Faibisoff A Silver B Silver S M Sabesin 《The American surgeon》1992,58(4):243-8; discussion 248-9
The safety and efficacy of piezoelectric extracorporeal shockwave lithotripsy in the treatment of symptomatic gallbladder stones were evaluated in 53 consecutively treated patients. All treatments were performed as outpatients without anesthesia; over 95 per cent of 109 treatments were performed without analgesia or sedation. Ursodeoxycholic acid was administered post-treatment. Seventy per cent of patients had multiple sessions. Cumulative stone-free rates of 38 per cent at 6 months, 65 per cent at 12 months, and 75 per cent at 15 months were achieved. There was no difference in eventual stone clearance between patients with single stones less than 20 mm diameter, single stones greater than or equal to 20 mm diameter, or multiple (two or three) stones, although patients with single smaller stones required significantly fewer total shocks to become stone-free (P = .02). Stone clearance correlated with estimated stone volume. Biliary pain occurred in 62 per cent of patients after treatment but ceased in stone-free patients. Biliary complications of pancreatitis (7.5%) and choledocholithiasis (3.8%) were successfully treated by endoscopic papillotomy. Nonbiliary complications were virtually nonexistent. Three patients (5.7%) had elective cholecystectomy. Results indicate that piezoelectric lithotripsy is a safe, minimally painful treatment that, in conjunction with oral bile acids, can produce stone-free rates of 75 to 100 per cent in selected patients. 相似文献
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INVOLVEMENT OF NON-NMDA AND NMDA RECEPTORS IN GLUTAMATE-INDUCED PRESSOR OR DEPRESSOR RESPONSES OF THE PONS AND MEDULLA 总被引:1,自引:0,他引:1
SY Chen WC Wu CJ Tseng JS Kuo CY Chai 《Clinical and experimental pharmacology & physiology》1997,24(1):46-56
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain. 相似文献
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47.
S S Pedersen H M?ller F Espersen C H S?rensen T Jensen N H?iby 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》1992,100(4):326-334
Patients with cystic fibrosis commonly acquire chronic pulmonary infection with alginate-producing Pseudomonas aeruginosa. The infection remains localized at the mucosal surfaces of the airways. Using enzyme-linked immunosorbent assays immunoglobulin concentrations and titers of specific antibodies to purified P. aeruginosa alginate and to P. aeruginosa sonicated antigens were measured in tears, saliva, sputum and serum. CF patients had significantly higher concentrations of IgG, IgA and SIgA in serum and saliva than controls. They also had significantly higher levels of specific antibodies to alginate and sonicated antigen in secretions and serum. Local production of IgA, IgG and IgM antibodies to P. aeruginosa was demonstrated. Only a minor proportion of specific IgA antibodies were present as secretory IgA in tears, saliva and sputum. The ratio of alginate-specific SIgA to specific monomeric IgA in sputum was significantly lower than the similar ratio in saliva, whereas the same ratio for specific P. aeruginosa sonicate antigens was found in saliva and sputum. 相似文献
48.
49.
S A Jensen L J Vatten P R Romundstad H O Myhre 《European journal of vascular and endovascular surgery》2003,25(3):209-212
OBJECTIVES: to investigate the prevalence of intermittent claudication (IC) in an unselected population of nearly 20000 individuals between 40 and 69 years of age.DESIGN: epidemiologic investigation of residents in Nord-Tr?ndelag County, Norway. MATERIAL AND METHODS: between 1995 and 1997, all residents 20 years of age or older in Nord-Tr?ndelag County, Norway, were invited to attend the HUNT Study. A total of 19748 participants between 40 and 69 years of age responded to questions related to the symptoms of intermittent claudication.We estimated the prevalence of IC based on these questions. RESULTS: the age-adjusted prevalence of intermittent claudication in the total population was 1.1% for men and 1.2% for women. We found an increase in the prevalence of IC by age, however, no sex differences were observed. CONCLUSION: the prevalence of intermittent claudication increased gradually by age. However, in contrast to previous reports, there was no difference by sex. 相似文献
50.
Nitrosocimetidine (NC) is the nitrosated derivative of cimetidine (Tagamet), a p.o. administered drug used widely in the treatment of stomach ulcers. NC is capable of methylating DNA in vitro and in cultured cells in a manner similar to that of the laboratory carcinogens 1-methyl-2-nitro-1-nitrosoguanidine and methylnitrosourea (MNU) and gives positive indications in short-term in vitro tests for genotoxicity, generally held to be prognostic of compound carcinogenic potential. Nevertheless NC has been found to be a weak or non-carcinogen in the rat and mouse model systems and to produce minimal levels of tissue DNA alkylation when dosed p.o. or i.v. to rats. The results from our earlier experiments (D. E. Jensen, Cancer Res., 43: 5258-5267, 1983) indicated that compound denitrosation is the primary fate of NC in the rat and suggested that denitrosation is the blood, mediated by hemoglobin sulfhydryl residues, is perhaps the major detoxification mechanism. We now report that whole blood and hemoglobin isolated from various mammalian species differ in their capacity for NC degradation rate enhancement and for compound denitrosation. The observed whole blood activity in the degradation reaction (rat greater than mouse/guinea pig greater than human/hamster) paralleled the hemoglobin activity. The NC half-life in isolated rat blood, 37 degrees C, was found to be about 2 min and in hamster or human blood 27 min. For reference, the MNU half-life in isolated blood is 8 min. Compound denitrosation accounted for at least 75% of the degradation in rat blood and 40 to 55% in human and hamster blood. Parallel NC denitrosation activity was found in the various hemoglobin preparations. The NC degradation rates in the presence of the several hemoglobin species were roughly proportional to the number of sulfhydryls on the hemoglobin tetramers available for reaction with p-chloromercuribenzoate and approximated the rates observed in solutions containing equivalent concentrations of L-cysteine. The percentage of total decomposition due to compound denitrosation in the presence of rat hemoglobin, 95%, was found to be unique relative to the L-cysteine-mediated reactions (about 35%) and the reactions studied over the pH range 6 through 10, the denitrosation process never accounted for more than 50% of the total degradation. Chemically blocking the sulfhydryls on human hemoglobin using iodoacetamide deleted the NC degradation rate enhancement. We found no evidence for nitrosylhemoglobin formation.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献