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排序方式: 共有549条查询结果,搜索用时 46 毫秒
521.
Tumor necrosis factor: immune endocrine interaction 总被引:6,自引:0,他引:6
Tumor necrosis factor (TNF), a peptide produced by macrophages in response to endotoxin, has been implicated as a mediator of septic shock. This study examined the effects of injections of recombinant (r) human TNF on circulating levels of metabolic substrates and hormones in conscious, unrestrained rats and the effects of TNF on cortisol secretion from human adrenocortical cells in vitro. Sublethal doses of rTNF--doses that did not produce hemodynamic changes in previous work--produced rapid (1 hour), significant increases in blood levels of glucose, lactate, and triglycerides and decreases in plasma levels of branched chain amino acids. Plasma levels of glucagon, corticosterone, ACTH, norepinephrine, and dihydroxyphenylglycol were also increased significantly. Incubation of adrenocortical cells with either 0.15 or 1.5 micrograms of rTNF increased cortisol secretion to the same extent as did 10(-10) mol/L ACTH. Administration of TNF produces a variety of metabolic and neuroendocrine effects including stimulation of anterior pituitary, adrenal cortical, and pancreatic secretion, and sympathoneural activation. These changes, and the in vitro results, are consistent with the view that immune cells can interact with endocrine cells through release of TNF. 相似文献
522.
Chui DK; Pugh ND; Walker SM; Gregory L; Shaw RW 《Human reproduction (Oxford, England)》1997,12(1):191-196
The aim of this prospective study was to investigate the ability of
transvaginal power Doppler ultrasonography to assess the relationship
between follicular vascularity and outcome in women undergoing in-vitro
fertilization. Each of 38 subjects underwent a single transvaginal power
Doppler ultrasound scan on the day of oocyte collection, where the
vascularity of individual ovarian follicles was assessed, using a
subjective system, and graded 1 to 4. In addition, conventional pulsatility
indices (PI) of the uterine and intra-ovarian (stromal) arteries were
calculated, which showed no significant differences between the pregnant
and non-pregnant groups. Using power Doppler ultrasonography, a total of
188 follicles was studied. The follicular vascularity grade was found to be
independent of follicular size and there was no significant difference in
fertilization rates with different degrees of vascularity, although there
was a trend towards higher fertilization rates with higher grade
vascularity. There were 10 pregnancies, giving a pregnancy rate of 26.3%
per embryo transfer. Pregnancies were confined to those women whose embryos
were derived from follicles with grade 3 and 4 vascularity (pregnancy rates
per embryo transfer of 12.5 and 61.5% respectively), with only those from
grade 4 follicles resulting in livebirths. This preliminary study suggested
that high grade follicular vascularity is associated with increased
pregnancy rate and that there is a possible link between follicular
vascularity and implantation potential.
相似文献
523.
A retrospective survey of symptomatology, treatment and course of disease in 45 patients with glomus tumours treated between 1959 and 1986 at the Radium Centre and ENT Department of the Aarhus University Hospital is presented. Nine patients were treated surgically, 7 had surgery and irradiation combined, and 25 patients were treated solely with radiation therapy. Six patients developed recurrence of tumours. Two patients died of tumour, one of them with pulmonary metastases. 相似文献
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527.
Osteoid osteoma 总被引:3,自引:0,他引:3
Osteoid osteoma is a benign skeletal neoplasm composed of osteoid and woven bone that rarely exceeds 1.5 cm in greatest dimension. The lesion is most commonly located in the cortex of long bones where it is associated with dense, fusiform, reactive sclerosis. Less often, it may be cancellous, where reactive osteosclerosis is usually less intense and may be distant from the lesion. Cancellous lesions are frequently intraarticular (most often in the hip) and may be associated with synovitis and joint effusion. Rarely, osteoid osteomas occur in a subperiosteal location. Patients are usually young, and there is a strong male predominance. Pain is the most common symptom. Radiographs of patients with cortical osteoid osteoma are often diagnostic. Intraarticular lesions, however, may be subtle, and scintigraphy may be required to locate the lesion for subsequent computed tomography (CT). CT is useful to identify and precisely locate the lesion and to provide guidance for percutaneous localization or treatment. 相似文献
528.
Manco LG; Lozman J; Coleman ND; Kavanaugh JH; Bilfield BS; Dougherty J 《Radiology》1987,163(3):727-730
One hundred twenty knees were examined prospectively with both axial computed tomography (CT) and magnetic resonance (MR) imaging to compare the value of these techniques in patients with clinical evidence of meniscal tears. Sixty-four of these knees were subsequently evaluated with diagnostic arthroscopy. In this group, CT was superior to MR imaging for meniscus evaluation in 29.7% of the knees, equal to MR in 54.7%, and inferior to MR in 15.6%. Although surface-coil MR imaging shows great promise and has numerous advantages over more conventional techniques, this preliminary experience suggests that, at least with certain imaging equipment and techniques, CT may be slightly more efficacious than 0.5-T MR imaging in meniscus evaluation. However, further comparative studies at higher field strengths are needed before the relative roles of CT and MR imaging can be established. 相似文献
529.
Alterations in response to pharmacological agents have been attributed to flow rate variation produced by intravenous infusion devices during drug delivery. A wide range of variation has been shown to occur with large-volume infusion devices. The intent of this investigation was to examine flow variation resulting from the use of selected small-volume syringe and mobile infusion devices and determine whether these devices have greater flow continuity than large-volume infusion pumps. Each syringe and mobile infusion device delivered iv fluid at three flow rates (1, 5, and 10 ml/h). The effusate was collected in a tared beaker and serial weights were measured every ten seconds using a computerized, gravimetric technique. Accuracy, continuity, and pattern of flow were determined for each of the syringe and mobile infusion devices. All of the devices produced accurate flow, within +/- 10 percent of the desired 5 and 10 ml/h rates. However, the actual iv flow rate ranged from 53 to 93 percent for the 1 ml/h rate. Continuity and pattern of flow resulting from each device were diverse. When compared with large-volume, microrate infusion devices, no significant differences could be observed. Therefore, no clear advantage to delivering drug solutions on a continuous basis can be expected from the use of small-volume devices. Specific infusion devices may be preferable for certain clinical applications; flow continuity data may be valuable when selecting an infusion device. 相似文献
530.