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951.
The effect of surgical glove powders (Biosorb, Keoflo, and CaCO3) and Hydrocote (powder-free lubricating agent, Biogel) was examined on human skin fibroblasts and monocyte/macrophage cell lines (U937 and HL-60). Glove powders (0.1-100 micrograms/ml) in the presence of 10% fetal bovine serum (FBS) had no significant effect on the rate of 3H-thymidine uptake and proliferation of these cells after 48 h and 7 days of exposure, respectively. However, they inhibited HL-60 growth after 10 days, and Biosorb and CaCO3 inhibited U937 after 10-21 days of exposure compared with control. In the presence of low serum (0.5%), Biosorb, but not Keoflo, CaCO3, and Hydrocote, inhibited HL-60 cells after the third day of exposure (p < 0.05), whereas they were without any effect on U937 cells. Further incubation resulted in a significant decrease in cell density in all treatments, as well as controls, because of cell death. In the presence of 2% serum, glove powder-treated HL-60 significantly increased in cell numbers during the first 3 days, and the cells became stationary thereafter, whereas Keoflo and CaCO3-stimulated U937 reached a maximal by 9 days of treatment. Coculturing of fibroblasts directly with macrophages (0.4-5 x 10(5) cells per dish) or incubation with macrophage culture-conditioned media (CCM) stimulated quiescent fibroblast growth equal to that induced by 10% and 0.5% serum, respectively (p < 0.05). However, incubation of fibroblasts with glove powder-treated HL-60 CCM (except CaCO3) inhibited (p < 0.05) and CCM from Biosorb-treated U937 stimulated (p < 0.05) fibroblast proliferation. The CCM from glove powder-treated HL-60 and U937 did not have any significant effect on the rate of 3H-thymidine incorporation into fibroblasts compared with controls. The present observations suggest that glove powder action on fibroblast and macrophage growth in vitro depends on both the serum concentration of the culture medium and the length of exposure. The results imply that glove powders may have an adverse effect in vivo by directly influencing the biologic activity of macrophages, as well as other cell types, leading to alterations in the early phases of wound healing. 相似文献
952.
Fu YL Hu YX Ling HL Ye ZZ Liang T Zhang MG Liu YK Kang B Luo YJ He SY Lian YJ 《Infectious diseases in obstetrics and gynecology》1994,1(5):235-241
Objective: The objective of this study was to determine whether human papillomavirus (HPV) infections are involved in the development of papillomatosis lesions of the lower female genital tract.Methods: A total of 616 biopsy specimens of genital papillomatous lesions (307 nodular and 309 papular types) from 598 patients were anaylyzed for the presence of HPV DNA sequences by polymerase chain reaction (PCR). These specimens were also examined by histopathological assessment for characteristic HPV-associated cytological changes, by immunohistochemical staining for HPV-associated antigen, and by electron microscopy for the presence of virions.Results: HPV DNA sequences were found in 97.9% (140 of 143 cases) and 1.1% (1 of 91 cases) of the nodular and papular papillomatosis cases tested, respectively. In 18 patients who had both types of papillomatosis lesions, HPV DNA was invariably found only in nodular tissues. HPV-associated antigen, koilocytosis, and virions were found in 53.6% (98 of 183 cases), 70.5% (129 of 183 cases), and 5.9% (5 of 85 cases) of nodular papillomatosis lesions tested, respectively.Conclusions: These data suggest that nodular papillomatosis was closely associated with HPV infection, but that papular papillomatosis of the lower female genital tract may have an etiology other than HPV infection. 相似文献
953.
Oakley D Yu MY Zhang YM Zhu XL Chen WH Yao L 《Journal of women's health / the official publication of the Society for the Advancement of Women's Health Research》1999,8(2):249-257
According to large-scale studies, oral contraceptive users become pregnant at rates that exceed ideal use failure rates. It is thought that a major cause is missed pills, but current research on consistent contraceptive pill taking is characterized by inadequate measures and a failure to investigate women's thinking about their own patterns of use. The purpose of this study was to gain some understanding about women's interpretations of consistency in their own pill taking through combining qualitative with quantitative data. The study was conducted in China, where contraception is free and widely available. Five urban and five rural oral contraceptive users were followed for up to three pill-taking cycles during 1996 for a total of 759 person-days. Consistency of pill taking was measured with electronic data obtained from a new blister package made by Anderson Clinical Technologies (Elmhurst, IL). Data from these devices were reviewed and interpreted by the study participants during in-depth private interviews. The users' reasons for missing pills included disruptions in their daily routines, their husband's absence, spotting, and trouble implementing the family planning program's instructions to take one pill per day for 22 days and start the next cycle on the fifth day of menses. One user gave these reasons for two cycles but denied missing numerous pills in her third cycle. Data from a series of four questionnaires showed that most demographic, psychosocial, and service system characteristics were not related to missed pills. However, results suggested that the daily routines of rural living may make consistent use more likely and that instructions for taking the pill may be associated with prolonged pill-free intervals and skipping pills during episodes of spotting. Three of the 10 women were at increased risk of pregnancy during the study period because of their pill-taking pattern. We concluded that the combination of qualitative with quantitative data enhances understanding of contraceptive use. Women themselves offer plausible reasons for their use behaviors. Listening to women could be useful in improving programs. 相似文献
954.
Thyroid health status of ammonium perchlorate workers: a cross-sectional occupational health study 总被引:5,自引:0,他引:5
Lamm SH Braverman LE Li FX Richman K Pino S Howearth G 《Journal of occupational and environmental medicine / American College of Occupational and Environmental Medicine》1999,41(4):248-260
Since pharmaceutical exposures to perchlorate are known to suppress thyroid function in patients with hyperthyroidism, a study of employees at a perchlorate manufacturing plant was conducted to assess whether occupational exposure to perchlorate suppresses thyroid function. Exposure to perchlorate was assessed by measurement of ambient air concentrations of total and respirable perchlorate particles, and systemic absorption was assessed by measurement of urinary perchlorate excretion. Airborne exposures ranged from 0.004 to 167 mg total particulate perchlorate per day. Urinary perchlorate measurements demonstrated that exposure to the airborne particulate perchlorate resulted in systemic absorption. Workers were grouped into four exposure categories with mean absorbed perchlorate dosages of 1, 4, 11 and 34 mg perchlorate per day. Thyroid function was assessed by measurement of serum thyroid-stimulating hormone, free thyroxine index, thyroxine, triiodothyronine, thyroid hormone binding ratio, thyroid peroxidase antibodies, and by clinical examination. No differences in thyroid-function parameters were found between the four groups of workers across approximately three orders of magnitude of exposure and of dose. Thus human thyroid function was not affected by these levels of absorbed perchlorate. In addition, no clinical evidence of thyroid abnormalities was found in any exposure group. The blood-cell counts were normal in all groups, indicating no evidence of hematotoxicity in this exposure range. The absence of evidence of an effect on thyroid function or blood cells from occupational airborne perchlorate exposure at a mean absorption of 34 mg/day demonstrates a no-observed-adverse-effect-level (NOAEL) that can assist in the evaluation of human health risks from environmental perchlorate contamination. 相似文献
955.
Smoking and the occurrence of Alzheimer's disease: cross-sectional and longitudinal data in a population-based study 总被引:4,自引:0,他引:4
Wang HX Fratiglioni L Frisoni GB Viitanen M Winblad B 《American journal of epidemiology》1999,149(7):640-644
The authors tested the hypothesis that smoking exerts a protective effect on Alzheimer's disease or dementia in a population-based cohort of 668 people aged 75-101 years (Sweden). Smoking was negatively associated with prevalent Alzheimer's disease (adjusted odds ratio = 0.6, 95% confidence interval 0.4-1.1) and dementia (adjusted odds ratio = 0.6, 95% confidence interval 0.4-1.0). Over 3-year follow-up (1989-1992), the hazard ratios of incident Alzheimer's disease and dementia due to smoking were 1.1 (95% confidence interval 0.5-2.4) and 1.4 (95% confidence interval 0.8-2.7). Mortality over 5-year follow-up was greater among smokers in demented (hazard ratio = 3.4) than nondemented (hazard ratio = 0.8) subjects. Smoking does not seem protective against Alzheimer's disease or dementia, and the cross-sectional association might be due to differential mortality. 相似文献
956.
V Wijendran R B Bendel S C Couch E H Philipson K Thomsen X Zhang C J Lammi-Keefe 《The American journal of clinical nutrition》1999,70(1):53-61
BACKGROUND: The fatty acids arachidonic acid (AA; 20:4n-6) and docosahexaenoic acid (DHA; 22:6n-3) are essential for fetal growth and development, but their metabolism may be altered in insulin resistance. OBJECTIVES: The objectives were to determine maternal plasma phospholipid polyunsaturated fatty acid concentrations in pregnant women receiving dietary therapy for gestational diabetes mellitus (GDM) and to identify maternal factors associated with plasma phospholipid AA and DHA concentrations in the third trimester. DESIGN: Fasting plasma phospholipid fatty acids were determined in women with GDM (n = 15) receiving dietary therapy only and in healthy, pregnant women without GDM (control group, n = 15) at 27-30, 33-35, and 36-39 wk gestation. RESULTS: Maternal plasma phospholipid (as % by wt of total fatty acids and mg/L) linoleic acid (18:2n-6), AA, and 22:5n-6 concentrations did not differ significantly between women with GDM and control subjects. The other n-6 long-chain polyunsaturated fatty acids (% by wt) were lower in GDM subjects than in control subjects. Plasma phospholipid (expressed as % by wt and mg/L) linolenic acid (18:3n-3) and summed precursors of DHA were lower and DHA (% by wt and mg/L), adjusted for dietary DHA intake, was 13% higher in GDM subjects than in control subjects. Maternal blood hemoglobin A1C was inversely related to plasma phospholipid AA (% by wt) (r = -0.56, P = 0.03) in control subjects and positively associated with plasma phospholipid AA (% by wt) in women with GDM (r = 0.76, P = 0.001). Pregravid body mass index was negatively associated with plasma phospholipid DHA (% by wt) in control subjects (r = -0.55, P = 0.04) and in women with GDM with a body mass index (in kg/m2) <30 (r = -0.76, P = 0.007). CONCLUSIONS: This is the first report documenting alterations in maternal plasma phospholipid PUFAs in pregnant women receiving dietary therapy for GDM. In pregnant woman, both with and without GDM, maternal glycemic control and pregravid BMI appear to be significant predictors of plasma phospholipid AA and DHA, respectively, during the third trimester. Additionally, dietary DHA significantly affects phospholipid DHA concentrations. 相似文献
957.
Snounou G Zhu X Siripoon N Jarra W Thaithong S Brown KN Viriyakosol S 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1999,93(4):369-374
Plasmodium falciparum isolates were obtained from Thai patients attending a malaria clinic on the Thai-Kampuchean border over 4 cross-sectional surveys carried out at 3-monthly intervals. The genetic structure of the parasite populations was determined by nested polymerase chain reaction (PCR) amplification of polymorphic regions of 3 P. falciparum antigen genes: msp1, msp2 and glurp. Although a high degree of diversity characterized these isolates, the overall population structure of the parasites associated with patent malaria infections was observed to remain relatively stable over time. The highest degree of polymorphism was observed with msp2, and the mean number of lines per infection (multiplicity of infection) calculated with this marker was higher than that obtained using msp1 or glurp alone, or combined. Infections with > or = 2 parasite lines were seen in 76% of the samples, and were proportionally more numerous at the start and end of the rainy season. Two interesting exceptions to the random distribution were observed and involved 2 allelic variants which in one case were found dissociated (msp1 MAD20-family) and in the other were associated (msp2 FC27-family). The epidemiological significance of these types of data is discussed. 相似文献
958.
Mifepristone regulation of leukemia inhibitory factor and uterine receptivity in rabbits 总被引:5,自引:0,他引:5
The effects of mifepristone on production of leukemia inhibitory factor (LIF) and uterine receptivity in rabbits was studied. In ovariectomized rabbits, LIF protein was at an undetectable level in control (score = 0), and upregulated by progesterone alone (score = 4). Estrogen had no additive effect, and may even have had a slightly negative effect when the rabbits were treated with both estrogen and progesterone (score = 3). Meanwhile, mifepristone obviously inhibited the stimulation of progesterone on the production of LIF in rabbit uterus (score = 1). The results also showed that LIF protein has a beneficial effect on uterine receptivity and mifepristone prevents this effect. The transfer of embryos to LIF-treated recipients significantly increased pregnancy (70%) and implantation rate (31%) as compared with control (pregnant rate = 50% and implantation rate = 17%). The transfer of embryos to LIF and mifepristone-treated recipients significantly decreased pregnancy (30%) and implantation rate (9%). The results of this study suggest that mifepristone prevented the effects of progesterone on LIF production and the beneficial effect of LIF on uterine receptivity. 相似文献
959.
A non-destructive method based on in-situ gamma spectroscopy is developed to determine the depth of radiological contamination in media. An innovative algorithm, Gamma Penetration Depth Unfolding Algorithm (GPDUA), uses point kernel techniques to predict the depth of contamination based on the results of the uncollided peak information from the in-situ gamma spectroscopy. The GPDUA is designed and verified through extensive Monte Carlo simulations and validated through laboratory experiments. This innovative tool promises to be "better, faster, safer, and cheaper" than the current practice in decontamination and decommissioning. The method requires the a priori knowledge of the contaminant source distribution. The applicable radiological contaminants of interest are any isotopes that emit two or more gamma rays per disintegration or isotopes that emit a single gamma ray but have gamma-emitting progeny in secular equilibrium with its parent (e.g., 60Co, 235U, and 137Cs to name a few). The predicted depths from the GPDUA algorithm using Monte Carlo N-Particle Transport Code simulations and laboratory experiments using 60Co have consistently produced predicted depths within 20% of the actual or known depth. 相似文献
960.