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41.

Introduction

Phytoestrogens are a group of compounds found in plants that structurally resemble the hormone oestradiol, and thus have the potential to act as oestrogen agonists or antagonists. Their potential effects may alter the risk of breast cancer, but only a limited range of phytoestrogens has been examined in prospective cohort studies.

Methods

Serum and urine samples from 237 incident breast cancer cases and 952 control individuals (aged 45 to 75 years) in the European Prospective into Cancer-Norfolk cohort were analysed for seven phytoestrogens (daidzein, enterodiol, enterolactone, genistein, glycitein, o-desmethylangolensin, and equol) using liquid chromatography/mass spectrometry. Data on participants' diet, demographics, anthropometrics, and medical history were collected upon recruitment. All models were adjusted for weight, fat and energy intake, family history of breast cancer, social class, analytical batch, and factors related to oestrogen exposure.

Results

Urinary or serum phytoestrogens were not associated with protection from breast cancer in the European Prospective into Cancer-Norfolk cohort. Breast cancer risk was marginally increased with higher levels of total urinary isoflavones (odds ratio = 1.08 (95% confidence interval = 1.00 to 1.16), P = 0.055); among those with oestrogen receptor-positive tumours, the risk of breast cancer was increased with higher levels of urinary equol (odds ratio = 1.07 (95% confidence interval = 1.01 to 1.12), P = 0.013).

Conclusion

There was limited evidence of an association between phytoestrogen biomarkers and breast cancer risk in the present study. There was no indication of decreased likelihood of breast cancer with higher levels of phytoestrogen biomarkers, but the observation that some phytoestrogen biomarkers may be associated with greater risk of breast cancer warrants further study with greater statistical power.  相似文献   
42.
The aim of the study was to evaluate the usefulness of 24-hour automatic recording of blood pressure and cardiac rhythm in patients with borderline hypertension. The study was performed in 50 patients aged 38.8 +/- 13.1 using the Del Mar Avionics device. Mean time of recordings was 21.3 hours, and the mean number of blood pressure measurements per one patient was 52.4. Great fluctuations of systolic blood pressure (from 92.1 +/- 12.6 to 191 +/- 37.0 mm Hg) and diastolic one (from 57.3 +/- 11.4 to 118.9 +/- 13.8 mm Hg) were observed. Mean systolic blood pressure (125.6 +/- 10.6 mm Hg) was significantly lower than the mean value of last three ambulatory measurements (141.9 +/- 9.8; p less than 0.001). Also mean diastolic pressure was lower than that obtained in the out patient clinic (84.7 +/- 9.7 vs 91.9 +/- 3.2 mm Hg; p less than 0.001). Mean heart rate during the day was 86.2 +/- 10.7 and at night 69.7 +/- 10.5 beats per minute. Ventricular and/or supraventricular cardiac arrhythmias were observed in 14 (28%) of examined patients. Results of the study indicate, that 24-hour automatic blood pressure recording is the valuable method, affording possibilities for more precise estimation of blood pressure and its 24-hour fluctuations in patients with borderline hypertension.  相似文献   
43.
We report our clinical experience with phototherapy in 3802 infants; 3629 were exposed to "standard" daylight phototherapy and 173 to "high-intensity" blue-light phototherapy. High-intensity blue-light phototherapy was twice as effective as standard daylight phototherapy in decreasing bilirubin concentrations. No failures occurred with high-intensity phototherapy compared with an overall failure rate of 1.84/1000 with daylight lamps; these cases were transferred to high-intensity phototherapy with prompt response. Rebound after cessation of phototherapy was greater in those exposed to high-intensity blue light with a significantly greater number requiring a second exposure. However, the incidence was still low. No third exposure was required in any infant. Nursing of infants under high-intensity blue light was more difficult and inconvenient as was clinical monitoring. The light also caused more stress on the nursing and medical personnel. However, the infants tolerated both types of phototherapy equally well. High-intensity blue-light phototherapy would seem to be the treatment of choice for infants with rapidly increasing or very high bilirubin levels, as well as in those not responding adequately to daylight phototherapy.  相似文献   
44.
Bagby  GC Jr; McCall  E; Bergstrom  KA; Burger  D 《Blood》1983,62(3):663-668
Human umbilical vein endothelial cells were cultured in supernatants of peripheral blood monocytes that had been cultured for 3 days with and without lactoferrin. Colony-stimulating activity (CSA) was measured in supernatants of the endothelial cell cultures and appropriate control cultures using normal, T-lymphocyte-depleted, phagocyte-depleted, low- density bone marrow cells in colony growth (CFU-GM) assays. Monocyte- conditioned medium contained a nondialyzable, heat labile factor that enhanced 4-15--fold the production of CSA by endothelial cells. The addition of lactoferrin to monocyte cultures reduced the activity of this monokine by 69%. Lactoferrin did not inhibit CSA production by monokine-stimulated endothelial cells. Therefore, vascular endothelial cells are potent sources of CSA, the production of CSA by these cells is regulated by a stimulatory monokine, and the production and/or release of the monokine is inhibited by lactoferrin, a neutrophil- derived putative feedback inhibitor of granulopoiesis. Inasmuch as a similar monokine is known to stimulate CSA production by fibroblasts and T lymphocytes, we suggest that mononuclear phagocytes play a pivotal role in the regulation of granulopoiesis by recruiting a variety of cell types to produce CSA.  相似文献   
45.
Yee  GC; Kennedy  MS; Storb  R; Thomas  ED 《Blood》1984,64(6):1277-1279
The effect of hepatic dysfunction, defined as abnormal serum bilirubin level, on oral cyclosporin (CSP) pharmacokinetics was examined in 28 marrow transplant patients who received CSP for prophylaxis of graft-v- host disease. Serum CSP concentrations were measured by radioimmunoassay. Forty-one concentration-time courses were studied, divided among patients with no (less than 1.2 mg/dL), mild (1.2 to 2.0 mg/dL), and moderate (2.0 to 5.0 mg/dL) hepatic dysfunction. CSP elimination, as determined by elimination rate constant and clearance, was delayed in patients with moderate hepatic dysfunction compared to those with no hepatic dysfunction (P less than .05). The volume of distribution, lag time for absorption, maximum serum concentration, and time at which the maximum concentration was achieved was not affected by hepatic function. These data indicate that patients with moderate hepatic dysfunction have delayed CSP or CSP metabolite elimination and may be at higher risk for developing CSP-related toxicity.  相似文献   
46.
Little is known about the etiology of adenocarcinoma of the distal esophagus/cardia, a cancer which has increased in incidence in the United States over the last two decades. We analyzed data on smoking, alcohol use, dietary intake, and other factors obtained from 173 hospitalized males with adenocarcinoma of the distal esophagus/cardia (cases) and 4,544 hospitalized males with diseases not related to smoking and of other organ systems than the gastrointestinal tract (controls). Cases of squamous cell carcinoma of the esophagus (n=136) and adenocarcinoma of the distal stomach (n=122) were included as separate case groups. All subjects were interviewed in 28 hospitals in eight cities in the US between 1981 and 1990. After adjustment for covariates, the odds ratio (OR) for adenocarcinoma of the distal esophagus/cardia for current smokers was 2.3 (95 percent confidence interval [CI]=1.4–3.9) and that for ex-smokers was 1.9 (CI=1.2–3.0) relative to never-smokers. The OR for drinkers of four or more ounces of whiskey-equivalents of alcohol per day (relative to those consuming less than one drink per week) was 2.3 (CI=1.3–4.3). Intakes of total fat and vitamin A from animal sources were significant risk factors and fiber intake was associated inversely with adenocarcinoma of the distal esophagus/cardia. Although the number of female cases of adenocarcinoma of the distal esophagus/cardia was small (n=21), significant associations were observed for smoking and alcohol.Dr Kabat is in the Department of Epidemiology and Social Medicine, Albert Einstein College of Medicine, Bronx, NY, USA. At the time of this work be was with the Division of Epidemiology, American Health Foundation, New York, NY. Drs Ng and Wynder are with the Division of Epidemiology, American Health Foundation. Address correspondence to Dr Kabat, Department of Epidemiology and Social Medicine, Albert Einstein College of Medicine, Belfer Bldg, Rm 1302, 1300 Morris Park Avenue, Bronx, NY 10461, USA. Supported by National Cancer Institute Program Project grant CA32617 and Center grant CA17613.  相似文献   
47.
Gallium scanning in lymphoid interstitial pneumonitis of children with AIDS   总被引:1,自引:0,他引:1  
Lymphoid interstitial pneumonitis (LIP) is a frequent pulmonary complication in the child with the acquired immune deficiency syndrome (AIDS) and human immunodeficiency virus (HIV) infection. We report the gallium scan findings in two children with AIDS and LIP. Gallium scintigraphy in both children demonstrated increased radionuclide concentration throughout the lungs, a pattern indistinguishable scintigraphically from that of Pneumocystis carinii pneumonia (PCP). This should alert nuclear medicine practitioners and referring physicians to another cause of diffusely increased gallium uptake in the lungs of patients with AIDS.  相似文献   
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