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21.
Adenoviruses from human immunodeficiency virus-infected individuals, including two strains that represent new candidate serotypes Ad50 and Ad51 of species B1 and D, respectively
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De Jong JC Wermenbol AG Verweij-Uijterwaal MW Slaterus KW Wertheim-Van Dillen P Van Doornum GJ Khoo SH Hierholzer JC 《Journal of clinical microbiology》1999,37(12):3940-3945
Adenovirus (Ad) isolates from a large number of human immunodeficiency virus (HIV)-infected individuals were compared serologically and genetically with Ad isolates from immunocompetent patients. Between 1982 and 1994, stool and urine samples from 137 subjects with AIDS hospitalized in The Netherlands yielded 143 Ad strains. Forty additional Ad strains were obtained from 35 HIV-positive patients in Manchester, United Kingdom, in 1992 and 1993. Of these 183 HIV-associated Ad strains, 84% belonged to species D and 3% belonged to species C. These strains were compared with 2,301 Ad strains collected during general diagnostic examinations in The Netherlands from 1973 to 1992. Of the latter strains, 5% belonged to species D and 49% belonged to species C. Two of the Ads isolated from fecal specimens of AIDS patients represent new serotypes: candidate Ad serotype 50 (prototype strain, Wan) of subspecies B1 and candidate Ad serotype 51 (prototype strain, Bom) of species D. The DNA restriction enzyme patterns of strains Wan and Bom differed from the patterns of all established prototypes. 相似文献
22.
Comparison of MRI with CT for the radiotherapy planning of prostate cancer: a feasibility study 总被引:4,自引:0,他引:4
Khoo VS Padhani AR Tanner SF Finnigan DJ Leach MO Dearnaley DP 《The British journal of radiology》1999,72(858):590-597
This feasibility study was performed to evaluate the suitability of MRI in defining appropriate pelvic radiotherapy treatment volumes, and to compare MRI sequences with CT for prostate cancer radiotherapy. Five patients with localized prostate cancer, imaged with four MRI sequences (spin echo (SE) T1, turbo SE (TSE) T2, high resolution TSE (HR) T2, and FLASH 3D (F3D)), compared with their corresponding CT planning scans. Segmentation ability of the following pelvic structures: prostatic apex (PA), prostate, rectum, bladder and seminal vesicles (SV), were evaluated by three independent observers. They used a five point grading scale based on the anatomical definition of the organ boundary, tissue contrast and multiplanar display. Results were averaged for the group and for each sequence. There was no significant interobserver variation in the assessed scores (p > 0.1). The average scores (+/- 1 SD) for all pelvic structures assessed by each imaging sequence were CT 1.3 +/- 0.6; SE T1 2.4 +/- 0.9; TSE T2 2.4 +/- 0.7; HR T2 2.2 +/- 0.7 and F3D 3.4 +/- 0.6. Compared with CT, the average MR score for each assessed pelvic structure was higher with a trend for all transaxial MR sequences to provide improved segmentation of the PA and rectum. The F3D sequence scored highest as it provided multiplanar views and avoided the problem of partial volume averaging. MRI, compared with CT, appears to provide improved definition of pelvic treatment volumes but further work is required to confirm this and to address the issues of MRI associated distortion and dosimetry before MRI can be used routinely for pelvic radiotherapy planning. 相似文献
23.
Mesenteric ischaemia is a rare but serious cause of abdominal pain. We present the case of a man with Sneddon's syndrome, who had symptomatic mesenteric ischaemia secondary to a superior mesenteric artery stenosis in conjunction with a hepatic artery stenosis. As far as the authors are aware, this has not previously been described in Sneddon's syndrome, which is a vascular systemic disease characterized by an association between cerebrovascular accidents and a livedo reticularis skin rash. He was treated with balloon angioplasty and stent insertion, with good symptomatic improvement. This has implications for other stenoses in this condition should they become symptomatic. 相似文献
24.
Cosmetic breast augmentation, and post-mastectomy breast reconstruction surgery using synthetic implants, have become established in surgical practice over more than 20 years. The operative technique for implant placement have changed somewhat during this time, as many different implant presentations have become available, but the same basic materials have remained in use. We have reviewed the present state of knowledge about breast implant materials with particular reference to the possible connection between polydimethylsiloxane and polyurethane to the so-called "Human Adjuvant Disease", and to carcinogenesis. Problems related to capsular contracture and mammography are also discussed. 相似文献
25.
Predictive value of serial carcinoembryonic antigen levels in long-term follow-up of ovarian cancer.
The predictive value of serial levels of carcinoembryonic antigen (CEA) in tumor monitoring was examined in 213 patients with ovarian cancer; each patient had been followed-up at monthly intervals for at least 12 months. CEA was not detectable throughout the period of observation in 35% of the patients. In general. patterns showing a disappearance of CEA or persistently low levels were associated with a good prognosis, whereas those showing a reappearance or highly elevated and rising levels were associated with a poor prognosis. A transient reappearance of CEA was observed in 10 patients; this did not appear to be associated with tumor recurrence or progression. "False positive" results were obtained in 6 patients in whom no tumor has been clinically detectable to date. "False negative" results were obtained in 4 patients with obvious tumor progression. In terms of a good or poor prognosis, the use of CEA levels was highly accurate in patients with minimal or no residual disease (97% and 89%, respectively); the rate fell to 62% in patients with extensive disease. As the clinical significance and limitations become better known, serial CEA levels should contribute substantially to the monitoring of patients with ovarian cancer. 相似文献
26.
27.
We report a case of an 80-year-old man with osteoblastic metastases from advanced carcinoma of the prostate presenting with a grand mal seizure resulting from severe hypocalcaemia. He had low serum phosphate and ionised calcium levels, elevated serum skeletal alkaline phosphatase and intact parathormone levels. 99mTc radioisotope bone scan revealed a "super bone scan" suggestive of osteomalacia. The serum 1, 25-dihydroxycholecalciferol level was unexpectedly elevated. The biochemical abnormalities persisted despite high dose calcium replacement, but improved with supraphysiological doses of 1,25 (OH)2 vitamin D3 (Rocaltrol) therapy. We hypothesise that the hypocalcaemia in this patient was due to vitamin D resistance secondary to a humoral factor secreted by the tumour. 相似文献
28.
29.
VS Khoo KH Liew EC Crennan IM D'Costa G Quong 《Journal of Medical Imaging and Radiation Oncology》1998,42(1):52-57
Thyroid dysfunction can develop in patients with Hodgkin's disease who are treated with mantle irradiation. During the period 1970-89, the records of 320 patients who received mantle irradiation and who had thyroid function tests (TFT) were retrospectively reviewed. The median age was 30 years (range, 7-69 years). The median mantle and thyroid dose was 36 Gy (range, 30-40 Gy) and 39.8 Gy (range, 32-65 Gy), respectively. Overall thyroid dysfunction was present in 39% of the patients. Clinical hypothyroidism was seen in 10% and biochemical hypothyroidism was noted in 25%. Hyperthyroidism was found in 4% of patients. Thyroid nodules had developed in six patients (2%), of which those in four patients were malignant. Age, sex, histological subtype, stage of disease, dose, lymphangiogram and treatment with chemotherapy were not significant factors in the development of thyroid dysfunction. The narrow dose range prevented adequate analysis of dose effect. The results indicate that the incidence of thyroid abnormalities is high enough to warrant regular TFT assessment with pre-irradiation levels and follow-up testing for life because the development of abnormalities can occur many years later. Thyroid examination should form part of the routine follow-up examination and any abnormality should be promptly investigated. 相似文献
30.
A total of 86 unrelated Malaysian patients with familial hypercholesterolaemia (FH) were studied for mutations in their low-density lipoprotein receptor (LDL-R) gene. Amongst them, 23 had a LDL-R gene mutation, while none having an Apolipoprotein B-3500 (Apo B-3500) mutation. Patients with the LDL-R gene defect appeared to have a higher level of low-density lipoprotein cholesterol (LDL-C), an increased incidence of xanthomas and coronary heart disease (CHD), but no relationships were found between the type of LDL-R gene mutations and their lipid levels or clinical signs of CHD. In contrast to Western data, our findings seemed to indicate a predominance of mutations in the ligand binding domain and an absence of Apo B-3500 gene mutation. The latter finding may offer a genetic basis as to why Asian patients with familial hypercholesterolaemia have lower LDL-C levels and less premature CHD than their Western counterparts. 相似文献