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E J Mayer B W Alderman J G Regensteiner J A Marshall W L Haskell J Baxter R F Hamman 《The American journal of clinical nutrition》1991,53(4):812-820
We evaluated the consistency of three questionnaire methods of assessing work and leisure activity in the rural biethnic population of the San Luis Valley Diabetes Study. A 7-d physical activity recall (PAR), a ranking of usual activity, and a history of usual participation in vigorous activity were used. Energy expenditure (kJ.kg-1.wk-1) (EE) was estimated from PAR. Subjects were 503 adults [49% non-Hispanic white (NHW), 51% Hispanic]. Physical activity at work rather than leisure-time activity largely determined total energy expenditure. Average EE at work increased with work rank for all subjects combined [mean EE (SEE) for rank 1 (low) = 324.2 (24.4), rank 4 (high) = 874.0 (102.1)] and within sex, ethnic, and occupational subgroups. Leisure EE increased with leisure rank only for NHW men and employed women. Similar patterns were observed in comparisons of PAR data with history of vigorous activity. Further development and validation of instruments appropriate for use across population subgroups are needed. 相似文献
3.
The effect of vitamin C nutriture on complement component C1q concentrations in guinea pig plasma 总被引:2,自引:0,他引:2
This study shows that guinea pigs fed 100 times the amount of vitamin C needed for growth and for prevention of scurvy have elevated levels of complement component C1q. C1q is a plasma protein rich in hydroxyproline, an amino acid whose biosynthesis requires ascorbate. C1q is essential for host defense against pathogens, both as a component of the classical complement pathway and as an opsonin in the phagocytosis process. We measured C1q in vitamin C-depleted guinea pigs that had been repleted for 4 wks with the following daily doses of ascorbate (mg/100 g body wt): 0.50 (suboptimal), 2.0 (adequate), 10 (ample) and 50 (tissue saturating). We measured C1q in three ways: indirectly by quantifying protein-bound hydroxyproline and directly by hemolytic assay and by immunodiffusion against anti-C1q. Regardless of the method, plasma C1q was 30-50% higher in animals fed tissue-saturating ascorbate than in those fed adequate or suboptimal amounts of the vitamin (p less than 0.05, one-way analysis of variance, least significant difference test). These data confirm and significantly extend earlier work that provided indirect evidence for a relationship between C1q and ascorbate nutriture in the guinea pig. They are consistent with a possible relationship between ascorbate nutriture and host defense. 相似文献
4.
外科医生和手术室人员经常接触手术设备产生的烟气,病人也会暴露于烟气中,特别是腹腔镜手术中产生的烟气滞留于腹腔内这一密闭空间并被吸收.这些烟气是一种与香烟烟气相似的毒性物质,然而对这种毒性物质的影响还未引起足够重视.应该采取必要措施尽可能减少手术中烟气的不良影响. 相似文献
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取代四氢异喹啉衍生物的合成及其生物活性 总被引:7,自引:0,他引:7
粉防己碱有钙拮抗作用,临床试用于治疗高血压,其裂解产物钙拮抗作用降低,但有α-肾上腺素能受体拮抗作用,本文以裂解物为先导化合物设计合成了两类取代的四氢异喹啉衍生物Ⅲ及Ⅳ。初步药理试验表明:大部分化合物有α-肾上腺素能受体拮抗作用,少数化合物钙拮抗活性有所增强,其中Ⅲ15,19对正常麻醉大鼠有一定的降压作用、Ⅳ17,19对实验性动物心律失常有明显的保护作用。部分化合物量化计算表明:化合物与α1-受体作用方式可能是形成电荷转移复合物。 相似文献
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Two fast magnetic resonance (MR) imaging techniques, advanced Fourier and partial-flip imaging, were used at 0.35 T to examine 21 patients with suspected intracranial lesions; the results were quantitatively compared with a conventional spin-echo study. Both of the fast MR techniques yielded a fourfold reduction in imaging time per section. The advanced Fourier sequence showed contrast that was identical to the conventional spin-echo study with signal-to-noise ratios of 58% and 57% for the first and second echoes, respectively. The partial-flip sequence showed a contrast of 109% and 57% for lesions versus substantia alba, and 107% and 78% for substantia grisea versus substantia alba relative to the first and second echoes of the conventional spin-echo study. The partial-flip sequence was particularly sensitive to magnetic susceptibility; this produced artifacts that may undermine the usefulness of partial flip for routine screening in certain parts of the brain. However, this susceptibility significantly improved the detection of intracranial hemorrhage when compared with the spin-echo sequence, particularly when combined with phase mapping of the partial-flip study. 相似文献
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Lung cancer stands as the most important malignant neoplasm in the United States because of its high prevalence, increasing incidence, high rate of mortality, and great potential for prevention through the control of cigarette smoking. The World Health Organization (WHO) classification of lung cancer identifies four major types: squamous cell carcinoma, adenocarcinoma, large cell carcinoma, and small cell carcinoma. These tumors are commonly divided into two groups based on differences in their biology and treatment: small cell (SCLC) and non-small cell carcinomas (NSCLC). This review analyzes NSCLC with a strong emphasis on the practical aspects of treatment. We give recommendations about smoking cessation and early diagnosis through screening of high-risk individuals. We review contemporary diagnostic and staging techniques in the context of the new international TNM system of staging. Subsequent discussions of treatment are based on this new staging system. We stress the pivotal role of surgery for the management of local disease, and in addition present the potential contributions of newer radiation therapy techniques. We examine chemotherapy in detail, including a review of the comparative activity of the available cytotoxic agents against NSCLC, the relative contribution of combination chemotherapy, and the role of surgical adjuvant treatment with either chemotherapy or immunotherapy. We advise that patients with NSCLC be treated under the aegis of modern clinical trials of new therapy whenever possible. When this is not possible, we recommend an individualized approach based on such factors as the patient's age, general state of health, cardiopulmonary status, psychosocial status, and personal system of values. 相似文献
10.
Linda Klieman MSN ANP Shauna Hyde MS RD CDE Kathy Berra MSN ANP William Haskell PhD 《Current cardiovascular risk reports》2007,1(4):335-339
The benefits of regular physical activity in older persons are numerous and well established. Regular physical activity in
older adults is associated with an overall improvement in health, functional capacity, quality of life, and independence.
Many questions arise for healthcare providers regarding an older person’s ability and motivation to be physically active.
The healthcare provider has a unique opportunity to assess the older client’s incentives, preferences, and abilities for physical
activities, as well as to prescribe a safe, appropriate, and enjoyable exercise plan. The exercise precription can be simple
yet thorough enough to ensure benefits in an older person’s health and functional capacity. 相似文献