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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
长期以来预言的人口老龄化现在已成事实。美国人口的“灰白化”在今后几年将加速,因为二战后生育高峰期出生的第一批儿童现在已达到传统的老年标准。因此,强调注意改善老年人的生活质量是恰如其分的。在本期杂志,Ciechanowski等^1的文章以及Bruce等最近发表的文章就报道了他们有关老年抑郁症治疗的试验结果。这些研究阐述了重要的进展,提出了应予认真考虑的广阔背景问题。 相似文献
992.
Ferrari Angela MD Lozzi Gian Piero MD Fargnoli Maria Concetta MD Peris Ketty MD 《Dermatologic surgery》2005,31(11):1448-1450
Background. A combined nevus most commonly consists of a blue nevus in combination with a Clark or Spitz nevus. Dermoscopically, combined nevus can mimic melanoma owing to the presence of dermoscopic features common to both types of lesions. Benign clinical and dermoscopic changes can occur in nevi over time, especially in children and young adults.
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
Objective. To describe the dermoscopic evolution of a congenital combined nevus showing unusual dermoscopic features.
Methods. Digital dermoscopic analysis was performed at the initial visit and after 8 months. The lesion was surgically excised and histopathologically examined.
Results. An asymptomatic plaque with a central blue area and peripheral brown pigmentation located on the back of a 13-year-old boy was diagnosed dermoscopically as combined nevus. Dermoscopic analysis 8 months later showed color changes from steel blue to gray-blue and black in the central area of the lesion, an increased number of blue-black dots or globules, and peripheral irregular streaks. Histopathology revealed typical features of a congenital combined nevus (blue nevus + compound nevus).
Conclusion. Over time, congenital combined nevus may show clinical and dermoscopic changes in size, color, and structure. Surgical excision is recommended when clinical and dermoscopic features are equivocal and the diagnosis of melanoma cannot be ruled out.
ANGELA FERRARI, MD, GIAN PIERO LOZZI, MD, MARIA CONCETTA FARGNOLI, MD, AND KETTY PERIS, MD, HAVE INDICATED NO SIGNIFICANT INTEREST WITH COMMERCIAL SUPPORTERS. 相似文献
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996.
Kun Hwang MD PhD Ei Tae Kim MD Se Il Lee MD DMSc 《The Journal of foot and ankle surgery》2005,44(6):473-477
The purpose of this study was to determine the genetic characteristics of foot polydactyly and identify its inheritance pattern by analyzing familial pedigree. Five cases from 2 Korean families were studied: 1 is a family whose members have been affected for 4 generations and the other for 2 generations. Using peripheral blood samples, we performed chromosomal analysis using the banding technique with Giemsa stain and karyotyping. We investigated the shape and structure of 46 chromosomes, looking for translation, deletion, inversion, ring chromosome, and isochromosome abnormalities. All peripheral blood samples demonstrated no chromosomal abnormalities, though the genetic nature of foot polydactyly and a new genetic locus was identified recently by other studies. Familial pedigree analysis suggested that polydactyly was inherited as an autosomal dominant trait in the first family. The mode of inheritance for the second family could not be determined due to an insufficient number of family members. The result of this study brought us to the conclusion that, while genetic factors play a major role in polydactyly, other factors may contribute to its occurrence. 相似文献
997.
998.
Ullmann Yehuda MD Shoshani Oren MD Fodor Adriana MD Ramon Yitzhak MD Carmi Nurit PhD Eldor Liron MD Gilhar Amos MD 《Dermatologic surgery》2005,31(10):1304-1307
BACKGROUND: The use of suctioned fat grafts for correction of soft tissue defects is a widespread procedure in esthetic and reconstructive surgery. The main disadvantage of this simple and sensible procedure is the unpredictable absorption rate of the fat graft. A lot of research has been performed aiming for enhancement of the take of the fat grafts. OBJECTIVE: Our study was performed to find if there is any favorable donor site for fat harvesting. METHODS: This in vivo experiment using the nude mice model enables the study of the long-term survival of human fat in an animal model. The fat was harvested from three donor areas: the thigh, abdomen, and breast of a 48-year-old woman who came for an elective esthetic procedure. After centrifugation, 1 cc of fat was injected subcutaneously into the scalp of the nude mouse. There were 15 mice in each of the three groups, according to the selected donor sites. The animals were sacrificed 16 weeks after the procedure. The extracted fat was evaluated in terms of weight, volume, and six histologic parameters: integrity, vascularization, cyst formation, fibrosis, necrosis, and inflammation. RESULTS: This study could not find any statistically significant differences between the three investigated donor sites in the evaluated parameters. CONCLUSION: On the basis of this study, there is no favorable area for harvesting fat grafts. The donor site can be chosen according to the preference of the surgeon and the patient. 相似文献
999.
直肠肛管恶性黑色素瘤的临床特征分析 总被引:12,自引:0,他引:12
目的了解原发性直肠肛管恶性黑色素瘤的临床特点。方法回顾性分析9例原发性直肠肛管恶性黑色素瘤的临床资料,并复习文献。结果直肠肛管恶性黑色素瘤以女性多见,平均发病年龄56岁,病程5.8个月;首发症状以血便为最常见,其次为肛门肿物突出。94.7%的直肠肛管恶性黑色素瘤在距离肛缘5.0cm范围内;肿瘤最大径(3.3±2.1)cm;其中54.5%可活动;有19.1%的肿瘤表面光滑;6.6%的肿瘤质地软;14.0%同期发现转移,肝转移最常见,腹股沟淋巴结转移其次;的病例出现误诊,超过者被误诊为良性疾病;手术治疗中以Miles术为主,经肛门局部切除术其次。结论直肠肛管恶性黑色素瘤极易误诊。手术治疗为主。 相似文献
1000.