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11.
J T Muldoon L A Wintermeyer J A Eure L Fuortes J A Merchant S F Van Lier T B Richards 《American journal of public health》1987,77(8):1006-1008
Health department epidemiologists in 50 states, New York City, and the District of Columbia were surveyed in 1985 about seven potential data sources for occupational disease surveillance. Reported sources of occupational disease data were: automated workers' compensation claims (63 per cent of the 52 respondents); provider reports (62 per cent); death certificates with occupation or industry (60 per cent); cancer registries with occupational histories (35 per cent); birth certificates with parent's occupation (27 per cent); non-cancer disease registries (13 per cent); and hospital or insurance records (8 per cent). 相似文献
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The Medical Research Council UKALL V trial for children with standard-risk acute lymphoblastic leukemia (ALL) (aged 1 to 14 years, leucocyte count less than 20 X 10(9)/L) was designed to determine whether the immunosuppressive effects of treatment could be reduced without sacrifice of antileukemic effect by alterations in the type of continuing therapy or in fractionation of cranial irradiation. Remission was achieved in 496 children on standard induction therapy, and 309 children received 24 Gy of cranial irradiation in ten to 16 fractions over 21 days, and 174 received 21 Gy in five to nine fractions over 21 days. The type of radiotherapy administered had no influence on relapse at any site or rate of death in remission. All 496 children were randomized to receive chemotherapy for 2 or 3 years with 6-mercaptopurine and methotrexate either as a continuous (group C) or a semicontinuous (group G) regimen or as a five-day pulse every 3 weeks (group I). All groups also received vincristine and prednisolone every 6 weeks. With a minimum follow-up of almost 7 years, patients in group I had significantly fewer remission deaths (P = .025) but a much higher rate of bone marrow relapse than those in group C or G (P = .002). There was an overall benefit for 3 years of chemotherapy compared with 2 years, which in contrast to previous studies, was more apparent in girls and in patients in groups C and G. Testicular relapse occurred in 37 boys, including 19 patients off therapy, with a previously negative biopsy. The overall results confirmed the prognostic significance of initial leucocyte count, even among these standard-risk patients, while girls had a superior rate of disease-free survival, but not of hematologic remission. It is concluded that, even among standard-risk patients, the prognosis is influenced by the height of the initial leukocyte count. While alterations in the fractionation of cranial irradiation do not appear to have influenced disease-free survival, intermittent continuing chemotherapy, although less immunosuppressive, is less effective than conventional continuous therapy in the treatment of ALL. In this study, 3 years of chemotherapy appeared superior to 2 years. 相似文献
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Motility disorders of the gastrointestinal (GI) tract have traditionally been diagnosed by excluding mechanical small-bowel obstruction. In order to diagnose GI motility disorders in a positive fashion, small-bowel manometry was performed on 15 patients who were referred to the authors with intestinal motility disorders. Intestinal manometry was performed after first positioning a 200-cm multilumen tube into the small intestine. Ports located at 10-cm intervals were perfused with sterile water and connected to pressure transducers to record intraluminal pressures with a multichannel chart recorder. This low compliance water perfusion manometry system allowed examination of both fasting and postprandial motility. Intestinal manometry was able to assist in the diagnosis of two patients that had true mechanical small-bowel obstruction. One patient had a stenosis of the gastrojejunostomy and three patients had a functional gastric outlet obstruction secondary to a motility disorder in the Roux limb. One patient had a functional obstruction from a reversed jejunal loop and eight patients were identified as having intestinal pseudo-obstruction. We found intestinal manometry was a helpful adjunct in the diagnosis of GI motility disorders. 相似文献
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S. Gray S. Lawrence A. Arregui N. Phillips R. Bell T. Richards T. Fukushima H. W. Taeusch 《Journal of the National Medical Association》1995,87(5):353-358
To study some of the factors relating to the care of mothers and newborns in an inner-city hospital, three sources of information were reviewed: an obstetric database including information on prenatal care and perinatal mortality, a database of all admissions to the hospital neonatal intensive care unit over the past 5 years, and a detailed questionnaire concerning attitudes and behaviors of recently delivered women. While analyses from these hospital-based data are not conclusive, the results add evidence for the following propositions: 1) Optimal prenatal care is infrequently obtained by mothers delivering at inner-city hospitals. Lack of prenatal care is clearly associated with increased perinatal mortality. While the need for prenatal care is appreciated by 98% of the mothers in this sample, the most frequent reasons why prenatal care is not obtained earlier or more frequently involve knowledge about and access to prenatal care. 2) Inner-city mothers, in general, manifest attitudes and behaviors that promote the welfare of their pregnancies and newborns. These attitudes and behaviors are in stark contrast to those that are frequently attributed to inner-city women by the media. 3) Acute perinatal medical and nursing care are perceived by many postpartum women as suboptimal, particularly in terms of the lack of respect shown to patients by nurses and doctors. 4) Improved acute obstetric and neonatal care improves perinatal morbidity and mortality of infants delivered at inner-city hospitals. 相似文献
17.
Interactions between paraquat, endogenous lung amines' antioxidants and isolated mouse Clara cells 总被引:1,自引:0,他引:1
The ability of paraquat to damage mouse lung Clara cells in the presence and absence of herbicide inhibitors is investigated using a cell culture system. Clara cell damage is assessed on the loss of nitroblue tetrazolium reductase activity and the inability to attach and spread on an extracellular matrix. Endogenous amines such as putrescine and spermidine reduce paraquat-induced damage at low concentrations indicating that they compete for the same cell surface receptor as paraquat and thus potentially block the accumulation of the herbicide. The efficacy of 10 microM exogenous putrescine as a protectant is reduced the longer the time before it is added to the cultures. Clara cells contain high levels of NADPH-dependent P-450 reductase which is required to redox cycle the paraquat and generate reactive oxygen radicals. Compounds with antioxidant properties are examined for their ability to reduce the Clara cell damage. Cystamine, the disulphide form of the naturally occurring thiol, cysteamine, and taurine, a metabolite of cystamine, both of which are accumulated in the lung, do not reduce paraquat-induced Clara cell damage. Another antioxidant, alpha-tocopherol is also ineffective but reduced glutathione (GSH), present in high quantities (3.2 mM) in clara cells, could reduce damage to the cultured cells. Cysteine, a precursor of GSH, can also prevent Clara cell damage when the concentration of paraquat is low. 相似文献
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G Tonolo M McMillan A M Richards P Montorsi J Polonia A Soro C Troffa N Glorioso 《Nephron》1990,55(1):58-62
Plasma immunoreactive atrial natriuretic factor (ANF) levels, their chromatographic profiles (high-performance liquid chromatography; HPLC) and changes during sequential ultrafiltration (UF; 1 litre/h) and biochemical correction without fluid removal (BC; 3 h) were studied in 8 end-stage chronic renal failure patients on intermittent haemodialysis (greater than 1 year). Patients entered randomly the UF-BC or BC-UF protocols that were reversed after 1 week. HPLC showed a single peak of ANF immunoreactivity in plasma of end-stage chronic renal failure patients before dialysis sessions. ANF at the end of fluid removal fell by 31 +/- 2% (p less than 0.01) during UF-BC and by 30 +/- 2% (p less than 0.01) at the end of BC during BC-UF. In both sequences a further slight reduction in plasma ANF was observed during the second phase: it was 8.5 +/- 5% (n.s.) during BC of the BC-UF and 12.5 +/- 2% (p less than 0.05) during fluid removal of BC-UF. Plasma ANF was not significantly removed by the machinery. BC did not modify the microhaematocrit in the BC-UF sequence while the microhaematocrit was significantly increased by UF (13 +/- 1 and 14 +/- 1%, p less than 0.005 vs. basal, respectively), and decreased by BC in the UF-BC sequence (-5 +/- 2% vs. end UF, p less than 0.05). Serum creatinine and urea decreased significantly during BC in both protocols while they were unmodified during UF. No significant changes were seen in PRC during either protocol.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献