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101.
BackgroundBariatric surgery is associated with an increased risk of delivering a small neonate. The role of maternal weight loss and surgery to conception interval is unclear.ObjectivesTo investigate the effect of maternal weight loss, as a result of bariatric surgery, and surgery to conception interval on fetal growth and birthweight (BW).SettingInner London Teaching HospitalMethodsWe studied prospectively nulliparous women with previous bariatric surgery. Information on type, time, and presurgery weight was obtained. Surgery-to-conception interval was calculated as the time between surgery and conception, defined as the fourteenth day of the pregnancy dated by first trimester ultrasound scan. In the first trimester, maternal weight was measured. Assessment of maternal weight change between presurgery and first trimester of pregnancy was defined as total weight loss (TWL) (%). Fetal ultrasound scans were performed twice; 30–32 and 35–37 weeks’ gestation and estimated fetal weight (EFW) was calculated. Fetal growth rate was calculated as the ratio of EFW increase (in grams) between 30–32 and 35–37 weeks divided by the time interval (in days) between the 2 examinations. BW was recorded.ResultsThe study included 54 pregnant women, 26 with a restrictive procedure (gastric band or vertical sleeve gastrectomy) and 28 with a gastric bypass. Surgery to conception interval was not a significant predictor of the offspring’s growth. Maternal TWL was a significant predictor of fetal growth rate (P = .04) and predictor of BW (P = .005), even after adjustment for confounders.ConclusionsMaternal weight loss, as a result of bariatric surgery, has an inverse correlation with fetal growth rate and BW.  相似文献   
102.
Culture of epithelial cells derived from the oviduct of different species   总被引:8,自引:2,他引:8  
This study proposes a procedure for the isolation and cultureof oviduct epithelial cells of several species. In-vitro cultureon such a feeder seems to allow full embryonic development andviability. The inner linings of Fallopian tubes from mouse,rabbit, cow and human were trypsinized and the epithelial cellswere enriched with Percoll gradient. Isolated cells, obtainedin high yield with good viability, were maintained in monolayerculture in B2-Menezo medium supplemented with serum, which alsosupports early embryonic development in vitro. The plated primarycultures reached confluence within 8 days, producting a monolayerof cohesive polygonalcells. Associated with this large epithelialcall population, ciliated cells as wellas polykaryotic cellsand few fibroblastic nestswere observed. After the first sub-culture,the ciliated cells disappeared and the epithelial cell monolayergrew rapidly to confluence with in 3 days and displayed contactinhibition. No epithelial cell growth could be obtained inculturein the absence of serum. The addition of oestrogens had no effecton any of the cultured oviductal epithelial cells. A sponotaneousalteration was observed in morphology and growth after severalpassages, the number of which depends mainly upon the species  相似文献   
103.
Three patients admitted to the surgical wards of Johannesburg Hospital in whom abdominal tuberculosis was suspected are presented. In every case difficulties were encountered in diagnosis and treatment. Each case presentation is followed by a short commentary on relevant aspects of abdominal tuberculosis.  相似文献   
104.
BACKGROUND--Although several investigations have shown a relationship between asthma (or its surrogate, airways responsiveness) and dietary or urinary sodium, others have not, and the matter remains controversial. This "salt effect" has been investigated during two recent epidemiological surveys of men in northern England. The first assessed the possible effect on airways responsiveness of occupational exposure to welding fumes, and the second characterised airways responsiveness in two geographically distinct residential areas. Thus, three separate study areas/populations were involved. METHODS--Investigation 1 involved 1059 shipyard workers aged 16-27 years who were exposed variously to welding fumes, and Investigation 2 involved 587 men aged 20-44 years who lived in rural West Cumbria or in urban Newcastle upon Tyne. In Investigation 1, a 24 hour urine specimen was requested from each subject with quantifiable airways responsiveness (PD20 < or = 6400 micrograms methacholine) and from an equal number of subjects without measurable airways responsiveness from the same occupational subgroup. In Investigation 2, every subject was asked to provide a 24 hour urine specimen. RESULTS--Of the men undergoing methacholine tests, satisfactory 24 hour urine specimens were obtained from 234 (22.1%) in Investigation 1 and 232 (39.5%) in Investigation 2. Analysis using multiple linear regression, multiple linear logistic regression, and multiple regression for censored data produced consistent results within each study population but conflicting results between them, such that there was no hint of a relationship between airways responsiveness and 24 hour urinary sodium excretion in the shipyard workers of Investigation 1 nor in the rural West Cumbrian population of Investigation 2, but an association was found in the urban Newcastle population of Investigation 2. All study populations were sufficiently large to demonstrate anticipated relationships between airways responsiveness and atopy, baseline FEV1, and (Newcastle only) age. CONCLUSIONS--If airways responsiveness is related to dietary sodium the relationship is not likely to be strong.  相似文献   
105.
BACKGROUND: In unselected patients, cardiac failure accounted for most deaths after antiarrhythmic operation (ER) for postinfarction ventricular tachycardia (VT). This study aimed to determine whether patients at low risk of this outcome could be predicted from a retrospective analysis of variables from 100 consecutive ER patients. METHODS: Thirteen variables suggested by other researchers as predictive of outcome were analyzed. At the time of study, ER was the only therapy available for drug refractory VT. RESULTS: Only emergency ER, wall motion score less than 3 and Killip classification were significantly related to death from cardiac failure. The lack of correlation between emergency ER and variables of ER timing, VT less than 24 hours of ER or VT type implies that the need for emergency ER is also related to ventricular dysfunction. Multivariate analysis identified a group at particularly low risk of death with a specificity of 95%. CONCLUSIONS: Patients at low risk of death after ER can be identified prospectively. In the implantable cardioverter defibrillator era, elective ER is best reserved for such patients. Emergency ER may still be justified in younger patients without comorbidity who will die of VT without it.  相似文献   
106.
Heightened awareness by health care funders of the need to find more efficient ways of using scarce health care resources has led to greater demand for evidence of cost-effectiveness. Implicit in this demand is that evidence is generated using clear reporting and accepted methods. The research reported here updates an earlier review of published cost-utility analyses (CUAs) to address whether previously identified gaps in reporting have diminished over time. Raising CUA standards requires systematic and regular reviews of published material to allow adequate monitoring and evaluation. There is also a need to 'appraise the appraisers' in the sense of reviewing peer-review processes. This is particularly so in those journals which are growing in importance as outlets for economic evaluation information. The findings from this study indicate continuing variation in the quality of reporting. At the lower end of this spectrum improvements could be made in the reporting of comparators, in the clarity of effectiveness evidence, in the assignment of utility weights to health states and in reporting of sensitivity analysis. CUAs published in peer-reviewed specialist medical journals were more likely to be lower in quality suggesting guidance on the appraisal of economic submissions needs to be extended to the editors of these particular journals. These findings could be used to help to target attempts to raise the quality of evidence-based CUA information.  相似文献   
107.
We studied the potential of both stereoisomers of 17-[123I]iodovinyloestradiol (E- andZ-[123I]IVE) and of 11-methoxy-17-[123I]iodovinyloestradiol (E-andZ-[123I]MIVE) as suitable radioligands for the imaging of oestrogen receptor(ER)-positive human breast tumours. The 17-[123I]iodovinyloestradiols were prepared stereospecifically by oxidative radio-iododestannylation of the corresponding 17-tri-n-butylstannylvi-nyloestradiol precursors. Competitive binding studies were performed in order to determine the relative binding affinity (RBA) of the unlabelled 17-iodovinyloes-tradiols for the ER in both human MCF-7 breast tumour cells and rat uterine tissue, compared with that of diethylstilboestrol (DES). Target tissue uptake, retention and uptake selectivity of their123I-labelled analogues were studied in immature female rats. All four 17-iodovi-nyloestradiols showed high affinity for the ER in human MCF-7 cells, as well as rat uterus. Their RBA for the ER showed the following order of decreasing potency: RBA of DES >Z-IVE >Z-MIVE >E-MIVE E-IVE. Neither of these 17-iodovinyloestradiols showed any significant binding to the sex hormone binding globulin in human plasma. The biodistribution studies showed ER-mediated uptake in the uterus, ovaries and pituitary, that ofE- andZ-[123I]MIVE being higher than that ofE- andZ-[123I]IVE. High target-to-non-target tissue uptake ratios, especially at longer periods after injection (up to 24 h), were exhibited by both isomers of [123I]MIVE. The uterus-to-blood uptake ratio was higher forE-[123I]MIVE. However, the uterus-to-fat uptake ratio appeared to be higher for theZ-isomer of [123I]MIVE, especially at 24 h after injection. Metabolic properties and temperature effects, which play a more important role in vivo, probably cause the discrepancies seen between in vitro and in vivo binding results. On the basis of their in vitro binding properties and in vivo distribution characteristics we conclude thatE- andZ-[123I]MIVE could be suitable radioligands for the diagnostic imaging of ER in human breast cancer. Therefore, further studies with these radioligands in mature normal and tumour-bearing rats are warranted.  相似文献   
108.
Background: The anticancer role of tumor necrosis factor-alpha (TNF-) has been limited by toxicity. These experiments evaluate blocking endogenous interferon-gamma (IFN-) activity to abrogate TNF- toxicity. Methods: C57Bl/6 mice bearing MCA 105 tumor were treated with TNF- and anti-IFN- antibody (Ab) to evaluate the effect on the acute lethality of TNF- and their efficacy as evaluated by tumor growth rate, tumor histology, and survival. Results: Anti-IFN- Ab decreased TNF- lethality. Anti-IFN- Ab alone increased tumor growth significantly more than did nonimmune IgG (p2<0.0001). Tumor-bearing mice that received nonimmune IgG and TNF- had slower tumor growth (p2<0.02) and a trend toward improved survival (p=0.07) compared with saline-treated controls. Anti-IFN- Ab abrogated the antitumor effect of TNF-, prevented acute tumor necrosis histologically, and resulted in tumor growth rate and host survival similar to that of controls. The findings in mice that received anti-IFN- Ab and high-dose TNF- were comparable with those in mice that received a lower, equitoxic dose of TNF- alone. Conclusions: Blocking endogenous IFN- accelerates tumor growth in this model and partially abrogates the toxic and antitumor activity of exogenous TNF- equally. This suggests that blocking endogenous IFN- activity is not a useful strategy for limiting TNF- treatment toxicity.Presented in part at the 45th Annual Cancer Symposium of The Society of Surgical Oncology, New York, New York, March 15–18, 1992.  相似文献   
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