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961.
ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a rare cause of Cushing's syndrome. Bilateral adrenalectomy is considered to be a standard therapy for AIMAH, although lifetime replacement of glucocorticoids is necessary after the procedure. This paper describes a subject with AIMAH who underwent unilateral adrenalectomy of the predominantly enlarged gland and subsequently displayed an improvement in insulin resistance and diabetes mellitus, the cardinal symptoms before the operation, concomitant with alleviation of abnormal cortisol secretion. The patient was a 61-year-old man with a body mass index of 25.6 kg/m2. He was diagnosed as having diabetes mellitus, hypertension, and hyperlipidemia at 50 years of age. Eight years after diagnosis, bilateral enlargement of the adrenal glands was revealed by chance upon computed tomography of the abdomen. Typical manifestations of Cushing's syndrome were not demonstrated. Basal levels of serum and urinary cortisol had not increased, although the serum cortisol level displayed no circadian rhythm and no response to the administration of dexamethasone. Despite sulfonylurea treatment, the patient's HbA1C level was as high as 7.6% (normal range 4.3-5.8%). Fasting insulin concentration was increased to 42.6 microU/ml, and the homeostasis model insulin resistance index (HOMA-R) was calculated to be 15.5 (with a normal range of less than 2.5), indicating severe insulin resistance. Unilateral adrenalectomy of the predominantly enlarged gland revealed that the resected gland consisted of multiple nodules of various sizes. Based on endocrinological, radiological, and pathological findings, a diagnosis of AIMAH was made. Ten months after the unilateral adrenalectomy, cortisol circadian rhythms were restored, and serum cortisol concentration was suppressed in response to the administration of low doses of dexamethasone, suggesting an improvement in the cortisol secretory pattern. Levels of HbA1C, fasting insulin, and HOMA-R decreased to 5.7%, 12.7 microU/ml, and 2.2, respectively. An improvement in hyperlipidemia was also observed. Insulin resistance and glucose intolerance are recognized as features of mild hypercortisolism. In the present case, unilateral adrenalectomy was effective in ameliorating insulin resistance and improving glycemic control. Unilateral adrenalectomy might be an alternative therapy for improvement of glucose and lipid metabolism in subjects with AIMAH.  相似文献   
962.
BackgroundDuring total hip arthroplasty (THA), the external iliac, femoral, and obturator vessels are at risk of vascular injury when penetrating the inner cortex of the pelvis. The purpose of this study was to clarify the location of these vessels using three-dimensional computed tomographic angiography (3DCT-A).MethodsWe enrolled 100 subjects (200 hips) without hip disease and performed examinations on the following. (1) External iliac–femoral vessels: we measured the shortest distance from these vessels to the pelvis on axial CT images and investigated the factors affecting distance. The anatomical course of the iliac artery was classified as straight, curved, or tortuous, and the correlation between course and age was established. (2) Obturator vessels: we measured the shortest distance from the obturator vessels to the quadrilateral surface on axial CT images. (3) Visualization of pelvic vessels was through the pelvis by dual-phase 3DCT-A.Results(1) The external iliac vein was located significantly closer to the pelvis than the artery, especially on the left side and in aged and female subjects. The single-curved and tortuous double-curved vessel types were found in aged subjects, and external iliac vessels of these types were closer to the pelvis than vessels of the straight type. In 36 subjects, the external iliac veins lay directly on the osseous surface of the pelvis (right 16, left 36). Of these 36 subjects, only one had straight-type vessels. (2) Obturator vessels were located just behind the acetabulum near the obturator foramen. (3) Reconstructed 3DCT images enabled us to visualize the pelvic vessels and demonstrated the danger area for penetrating the inner cortex of the pelvis.ConclusionUnderstanding the anatomical orientation of the pelvic vessels around the acetabulum using 3DCT-A could be helpful for preventing vascular injury during THA.  相似文献   
963.
To test liposome‐encapsulated hemoglobin (LEH) in transient cochlear ischemia/reperfusion as a model of sudden deafness, Mongolian gerbils were randomly assigned to receive 2 mL/kg of either low‐affinity LEH (l‐LEH, P50O2 = 40 mm Hg), high‐affinity LEH (h‐LEH, P50O2 = 10 mm Hg), homologous red blood cells (RBCs), or saline (each group n = 6) 30 min before 15‐min occlusion of the bilateral vertebral arteries and reperfusion. Sequential changes in hearing were assessed by auditory brain response 1, 4, and 7 days after ischemia/reperfusion, when the animals were sacrificed for pathological studies. h‐LEH was significantly more protective than l‐LEH in suppressing hearing loss, in contrast to RBC or saline treatment, at 8, 16, and 32 kHz, where hearing loss was most severe (P < 0.05 between any two groups) on the first day after cochlear ischemia/reperfusion. Thereafter, hearing loss improved gradually in all groups, with a significant difference among groups up to 7 days, when morphological studies revealed that the inner hair cells but not the outer hair cells, were significantly lost in the groups in the same order. The results suggest that pretreatment with h‐LEH is significantly more protective than l‐LEH in mitigating hearing loss and underlying pathological damage, in contrast to transfusion or saline infusion 7 days after transient cochlear ischemia/reperfusion.  相似文献   
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966.
Over the last 60 years, Japanese people have experienced a rapid and drastic change in lifestyle, including diet. Suspicions have been raised that so‐called ‘Westernization’, characterized by a high‐calorie diet and physical inactivity, is associated with increasing trends in the incidence of cancer of the colon, liver, pancreas, prostate, and breast, as well as type 2 diabetes. Epidemiological evidence from our prospective study, the Japan Public Health Center‐based Prospective (JPHC) study, and systematic literature reviews generally support the idea that factors related to diabetes or insulin resistance are associated with an increased risk of colon (mostly in men), liver, and pancreatic cancers. These cancers are inversely associated with physical activity and coffee consumption, which are known to decrease the risk of type 2 diabetes. The suggested mechanism of these effects is that insulin resistance and the resulting chronic hyperinsulinemia and increase in bioavailable insulin‐like growth factor 1 (IGF1) stimulate tumor growth. In contrast, associations with diabetes are less clear for cancer of the colon in women, and breast and prostate, which are known to be related to sex hormones. The effect of insulin resistance or body fat on sex‐hormone production and bioavailability may modify their carcinogenic effect differently from cancers of the colon in men, and liver and pancreas. In conclusion, there is substantial evidence to show that cancers of the colon, liver, and pancreas are associated with insulin resistance, and that these cancers can be prevented by increasing physical activity, and possibly coffee consumption. (Cancer Sci 2010; 101: 1073–1079)  相似文献   
967.

Objective

To evaluate whether magnetic resonance imaging (MRI) of the wrists and finger joints and an analysis of serologic autoantibodies are clinically meaningful for the subsequent development of rheumatoid arthritis (RA) in patients with undifferentiated arthritis (UA).

Methods

A total of 129 patients with UA, a disease status formally confirmed by a rheumatologist over a period of at least 1 year, were included. Gadolinium‐diethylenetriamine–enhanced MRI of both wrists and finger joints and serologic variables were examined upon admission to our Early Arthritis Clinic at Nagasaki University. After a prospective followup of 1 year, a predictive value for the development of RA was determined for each patient.

Results

The subjects were evaluated for their positive or negative status with respect to 3 objective measures at study entry: anti–cyclic citrullinated peptide (anti‐CCP) antibodies and/or IgM‐rheumatoid factor, MRI‐proven symmetric synovitis, and MRI‐proven bone edema and/or bone erosion. The patients who were positive for at least 2 of these measures progressed to RA at 1 year with a 79.7% positive predictive value (PPV), 63.0% negative predictive value, 75.9% specificity, 68.0% sensitivity, and 71.3% accuracy. Furthermore, in 22 UA patients positive for both anti‐CCP antibodies and MRI‐proven bone edema who were considered to have progressed to RA at 1 year, the PPV was increased to 100%. A close correlation was found between the present rule and that established in the Leiden Early Arthritis Cohort.

Conclusion

MRI‐proven early joint damage in conjunction with serologic autoantibodies is efficient in predicting progression from UA to RA. This method can be used to identify patients who would benefit from early treatment with disease‐modifying antirheumatic drugs.  相似文献   
968.
Accuracy of methods to assess past diet in retrospective studies is of concern. Adjustment of current intake for subjects’ perceptions of change is one alternative to estimate past intake. The authors studied the potential utility of perceived change in diet in residents of a rural Japanese community who participated in three sequential surveys with self‐administered questionnaires. Frequencies of consumption for 27 foods were investigated in the first and second questionnaires administered in 1988 and 1993 (n = 451), and perceived changes in their frequencies during this period were asked in the second and third questionnaires surveyed within two weeks (n = 214). Perceptions of change in diet were highly reproducible. At a group‐level analysis, they were consistent with the changes in food frequencies in 21 of the 27 items. Nevertheless, whereas current diet adjusted for perceived change correlated better with past intake than did current intake alone in 17 foods, improvement in Pearson's correlations was only marginal (median = 0.02). Perceptions of change in diet would therefore be of limited utility in improving estimate of past intake among individuals in retrospective studies.  相似文献   
969.
970.
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