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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
31.
Annalisa Volpi Francesco Bacci Angelo Paradiso Luca Saragoni Emanuela Scarpi Monica Ricci Mirella Aldi Simonetta Bianchi Pietro Muretto Fiorella Nuzzo Gianni Simone Anita Mangia Francesco Schittulli Dino Amadori 《Modern pathology》2004,17(9):1038-1044
Available results highlight the lack of good level of evidence studies on the pure prognostic value of histological grade. In the present study, the prognostic relevance of histological grade and of its three components, tubule formation, nuclear pleomorphism and mitotic count, was analyzed in a series of 372 patients with node-negative breast cancer treated with locoregional therapy alone until early relapse. Histological grade was determined blindly by two observers and discordance between evaluations was resolved after joint review using a multihead microscope. No relation was observed between histological grade and any of its three components and disease-free survival. Conversely, a significant relation was observed between histological grade and distant metastasis-free survival (at 6 years, 94, 86 and 76% for grades 1, 2 and 3, respectively, P=0.013) as well as overall survival (98, 90 and 86%, P=0.001). A breakdown analysis as a function of the three components showed that neither tubule formation nor nuclear pleomorphism was associated with prognosis, and only mitotic count strongly influenced both distant metastasis-free survival (91, 82 and 74%, P=0.014) and overall survival (97, 87 and 85%, P=0.011). Histological grade suffers from a much higher subjectivity than any other microscopic evaluation of biomarkers as it is the sum of three different morphological features. Within the Italian Network for Quality Assessment of Tumor Biomarkers program we observed that histological grade is an independent prognostic variable, but also that this role is ascribable only to the number of mitotic figures. In conclusion, due to the ever smaller size of diagnosed breast cancers, resulting in less cancer tissue for biofunctional and molecular analysis, mitotic count evaluated under strict quality control conditions seems to be an accurate and feasible prognostic variable. 相似文献
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Paula Jablonski Kirsty Baxter Brian O. Howden Anita C. Thomas Vernon C. Marshall Alicia Stein-Oakley Napier M. Thomson 《ANZ journal of surgery》1995,65(2):114-119
A reproducible animal model is essential for the study of the pathogenesis of chronic rejection. This study investigates: (i) the optimal pre-transplant blood transfusion conditions to induce tolerance in a strongly rejecting rat kidney allograft model (Dark Agouti to Albino-Surgery) and avoiding post-transplant immunosuppression; (ii) the functional and histological changes that occur in long-term surviving kidneys and their similarity to chronic rejection; and (iii) the maintenance of tolerance. Prolonged survival occurred after administration of at least two donor blood transfusions with concomitant cyclosporin A (5 mg/kg per day). The time-span between transfusions appeared to be critical: 4 days was more effective than 2 or 7 days. Ineffective treatment led to death within the first 2 weeks post-transplant with histological evidence of acute graft rejection. Seventy-five per cent of long-term survivors experienced impaired renal function in the first week which improved spontaneously and remained stable in 93% of the surviving animals after 100 days and in 668 after 200 days. The morphology of long-term allografts was extremely variable from minor to extensive tubular atrophy, interstitial fibrosis, glomerular hypertrophy, focal and segmental glomerulosclerosis and vascular changes. Glomerular hypertrophy occurred in uninephrectomized controls and probably denoted a response to uninephrectomy. Glomerulosclerosis increased with time and was absent in controls. Although chronic damage was evident, the rats remained tolerant to fresh donor skin. Replacement of the original kidney allograft with a fresh donor kidney resulted in 70% survival. These second grafts showed less severe renal dysfunction and morphological damage than the original allografts in the long-term follow up. 相似文献
34.
Lymphoma presenting as a salivary gland mass 总被引:2,自引:0,他引:2
M A Schusterman M S Granick E R Erickson E D Newton D C Hanna R W Bragdon 《Head & neck surgery》1988,10(6):411-415
A retrospective review of 36 cases of lymphoma presenting as a salivary gland mass was conducted over a 34-year period. A significant increase in the occurrence of lymphoma was noted in proportion to other salivary gland tumors (P less than 0.01, chi 2 analysis: 1954-1972, 11 of 714 (1.5%); 1973-1979, 9 of 201 (4.5%); 1980-1987, 16 of 265 (6.0%). The mean age was 61 years, sex distribution was equal, and 75% occurred in the parotid. Only 42% presented with signs or symptoms other than a painless mass. Glandular excision was done in early stages of the disease while biopsy was done at later stages. Frozen section analysis was accurate in all but one case and was useful in determining if biopsy were adequate. All patients were definitively treated with chemotherapy and/or radiotherapy. Several instructive points are apparent. Any patient presenting with an isolated salivary gland mass can have a lymphoma. There has, in fact, been a significantly increasing proportion of salivary gland lymphoma among the various salivary gland tumors in our patient population. In contrast to other salivary gland tumors, surgery is reserved for diagnosis and not for treatment. A lymph node biopsy may be sufficient to establish a diagnosis, in which case, glandular excision is unnecessary. Most of the patients presented with an asymptomatic isolated salivary gland mass. The presence of adjacent adenopathy, a rubbery feel to the mass, and the intraoperative appearance were the most suggestive signs of lymphoma. Frozen section analysis is helpful in determining the appropriate extent of surgery and is recommended. 相似文献
35.
F. A. Ashley B. Gibson B. Daly S. Lygo Baker J. T. Newton 《European journal of dental education》2006,10(1):10-19
The aim of this study was to explore undergraduate and postgraduate dental students' understanding of a good learning experience by using 'reflection on learning' as described by Schon. Four groups of Year 4 BDS students and one group of postgraduate students in dental public health took part in a series of focus group discussions. The responses were grouped into four broad themes (a) active, practical and positive learning; (b) interactive/together learning; (c) personal learning; (d) theory into practice. Six educational models of good learning proposed by the students are described. 相似文献
36.
Summary Ependymomas, glial neoplasms usually arising in the posterior fossa or spinal cord, rarely metastasize outside the central nervous system. We have reviewed all 81 ependymomas evaluated at MSKCC between 1956–1989. Five (6.2%) had extraneural metastases (ENM). The primary tumor was in spinal cord in 3 patients and the cerebral hemisphere in 2. Two tumors were histologically anaplastic; 3 were histologically benign. The 5 patients were 3, 3, 3.5, 16 and 37 years old. Time from initial diagnosis to development of ENM was 0, 15, 35, 40, and 288 months. At the time of ENM the primary tumor was progressing in 4/5 patients. Prior therapy had included resection plus radiation therapy (RT) (1), RT plus chemotherapy (1), resection plus RT plus chemotherapy (2). One patient had not received prior therapy because ENM were present at diagnosis. The sites of ENM included lung and thoracic lymph nodes (2), pleura and peritoneum (2), and liver (1). Both patients with peritoneal ENM had had ventriculoperitoneal shunts. ENM did not correlate with histologic grade, age, or degree of surgical resection. When patients with ependymoma develop signs or symptoms of systemic disease such as abdominal pain, cough, or adenopathy, ENM should be considered. 相似文献
37.
Osteoclastoma of the calvarial bone of membranous origin is a rare entity. This paper presents a case of osteoclastoma of the occipital bone and a brief review of literature. 相似文献
38.
Ossifying fibroma of the sellar turcica is extremely rare. There are only sporadic case reports in the literature. One such case simulating pituitary adenoma is presented in an 18-year-old girl. 相似文献
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