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61.
Hirohito Yano Takashi Funakoshi Jun Shinoda Noboru Sakai George Kokuzawa Kuniyasu Shimokawa 《Brain tumor pathology》1997,14(1):75-78
A 35-year-old woman had an intradural tumor in the posterior fossa adjacent to the posterior wall of the left pyramidal bone,
which was totally removed and histologically diagnosed as a pleomorphic adenoma. Follow-up examination for 2 years showed
no recurrence of the tumor. There was no primary lesion in any other gland of the body, and therefore there is no alternative
but to conclude a “migration” of some gland cells. The pathogenesis of this tumor remains unclassified. 相似文献
62.
P de Lonlay-Debeney JC Fournet D Martin F Poggi C Dionisi Vicci M Spada G Touati J Rahier F Brunelle C Junien JJ Robert C Nihoul-Fékété JM Saudubray 《Archives de pédiatrie》1998,5(12):1347-1352
Persistent hyperinsulinemic hypoglycaemia of infancy (PHHI) is the most frequent cause of hypoglycaemia in infancy. Clinical presentation is heterogeneous, with variable onset of hypoglycaemia and response to diazoxide, and presence of sporadic or familial forms. Underlying histopathological lesions can be focal or diffuse. Focal lesions are characterised by focal hyperplasia of pancreatic islet-like cells, whereas diffuse lesions implicate the whole pancreas. The distinction between the two forms is important because surgical treatment and genetic counselling are radically different. Focal lesions correspond to somatic defects which are totally cured by limited pancreatic resection, whereas diffuse lesions require a subtotal pancreatectomy exposing to high risk of diabetes mellitus. Diffuse lesions are due to functional abnormalities involving several genes and different transmission forms. Recessively inherited PHHI have been attributed to homozygote mutations for the beta-cell sulfonylurea receptor (SUR1) or the inward-rectifying potassium-channel (Kir6.2) genes. Dominantly inherited PHHI can implicate the glucokinase gene, particularly when PHHI is associated with diabetes, the glutamate dehydrogenase gene when hyperammonaemia is associated, or another locus. 相似文献
63.
D. A. Saltzman B. Chavers W. Brennom R. Vernier R. L. Telander 《Pediatric surgery international》1998,13(4):268-270
Hemolytic uremic syndrome (HUS) consists of an acute onset of microanglopathic hemolytic anemia, thrombocytopenia, and renal
dysfunction. HUS-associated colitis can be seen in up to 100% of patients and is usually associated with severe abdominal
pain and distention. Colonic perforation is a complication of HUS that has a reported incidence of 1%–2%, and although there
are several case reports in the literature describing perforation of the colon, it is still very difficult to discern the
abdominal symptoms associated with HUS colitis from perforation. Four cases of colonic perforation are reported here from
a consecutive series of 57 patients, in which a trend in the length of time from the onset of symptoms of HUS to colonic perforation
was determined. A review of the literature for cases of HUS-associated colonic perforation was also performed. The time from
the onset of HUS symptoms to colonic perforation in our series was similar to that found in the literature review (11 ± 5
vs 14 ± 8 days). Awareness that this complication has a tendency to occur towards the end of the 2nd week during the course
of HUS is essential to avoid an unnecessary and untimely surgical intervention.
Accepted: 25 June 1997 相似文献
64.
Genetic Alterations of Mixed Hyperplastic Adenomatous Polyps in the Colon and Rectum 总被引:1,自引:2,他引:1
Hiroyuki Uchida Hiroshi Ando Keiji Maruyama Hiroshi Kobayashi Hiroshi Toda Hiroshi Ogawa Takachika Ozawa Yasuhide Matsuda Haruhiko Sugimura Takashi Kanno Shozo Baba 《Cancer science》1998,89(3):299-306
Some mixed hyperplastic adenomatous polyps (MHAPs) contain dysplastic lesions or even carcinomas. These polyps are considered to be different from ordinary hyperplastic polyps and may have a preneoplastic potential. We investigated APC and K- ras mutations in MHAPs of the colon and rectum, and also in colorectal adenomas and hyperplastic polyps to identify molecular differences between MHAPs, adenomas and hyperplastic polyps, using direct sequencing of mutation cluster regions (MCR) in APC and K- ras . No APC mutations were identified in 12 MHAPs and 8 hyperplastic polyps, whereas 10 of 27 (37.0%) adenomas showed somatic mutations. K- ras mutations were identified in one of 12 (8.3%) MHAPs, one of 8 (12.5%) hyperplastic polyps, and 10 of 27 (37.0%) adenomas. p53 mutation was found in a carcinoma arising in an MHAP. Mutations other than APC mutations may play a role in the development of MHAPs. 相似文献
65.
目的研究垂体腺瘤(pituitary adenoma)中细胞粘附分子(CD44)的表达,探讨CD44蛋白在垂体腺瘤侵袭性生长中的意义.方法用免疫组化(SP)的方法检测38例垂体腺瘤中CD44s、CD44v5蛋白的表达.结果20例侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为75%、35%.18例非侵袭性垂体腺瘤中CD44s、CD44v5阳性率分别为27.8%、22.2%.CD44s在侵袭性垂体腺瘤中表达的阳性率明显高于非侵袭性垂体腺瘤,其差异具有显著性(P<0.01),CD44v5在侵袭性垂体腺瘤中和非侵袭性垂体腺瘤中的表达率均较低,无显著性差异(P>0.05).结论CD44s在侵袭性垂体腺瘤中呈高表达,与垂体腺瘤的侵袭性生长有关,在垂体腺瘤的侵袭性生长过程中起重要作用.CD44v5在垂体腺瘤中的表达较低,与垂体腺瘤生长方式无关. 相似文献
66.
HSV-tK与IL-2基因对涎腺多形性腺瘤细胞的杀伤作用 总被引:1,自引:0,他引:1
目的:观察腺病毒介导的单纯疱疹病毒胸苷激酶基因(HSV-tK)和白细胞介素-2基因(IL-2)联合杀伤人涎腺多形性腺瘤细胞的效果.方法:采用腺病毒介导的HSV-tK基因和IL-2基因联合转染人涎腺多形性腺瘤细胞;采用逆转录聚合酶链式反应(RT-PCR)检测转染后细胞的基因表达;采用四唑盐比色(MTT))法测定tK与IL-2基因对肿瘤细胞的杀伤作用及旁观者效应:采用光镜观察基因治疗后肿瘤细胞的形态学变化.结果:单独转染HSV-tK/GCV及IL-2基因5天后,涎腺多形性腺瘤细胞的存活率分别为37.7%和66.0%:联合转染5天后,细胞的存活率降至21.5%,与前二者相比差异有显著性(P<0.05).结论:HSV-tK和IL-2基因联合使用对涎腺多形性腺瘤的杀伤作用高于上述基因单独使用的杀伤作用. 相似文献
67.
Proliferation, Vascular Endothelial Growth Factor Expression and Cavernous Sinus Invasion in Growth Hormone Secreting Pituitary Adenomas 总被引:4,自引:0,他引:4
Summary Surgical cure of growth hormone producing pituitary adenomas (GHomas) becomes difficult when they invade the cavernous sinus
(CS). Tumour proliferative activity and angiogenesis are thought to be required for tumour growth and invasion, and vascular
endothelial growth factor (VEGF) activates neovascularization around tumours. In this study, the mechanism and clinical significance
of CS invasion is analysed. In 25 surgically treated GHomas, the extent of CS invasion was classified as high (Knosp's grade
3 and 4), and low (grade 0, 1 and 2) MR grades, and the MR grades were compared with tumour proliferative potential (Ki-67
expression), angiogenetic demand (VEGF expression), volume of adenomas and serum hormone levels.
The Ki-67 index of high MR grade adenomas (1.17±0.62%) was significantly higher than that of low MR grade adenomas (0.55±0.42%,
p=0.027), whereas VEGF expression showed no significant correlation with MR grades (p>0.999). Tumour volume also showed a
significant correlation with MR grade (p=0.002). VEGF expression was not correlated with serum hormone level and volume, but
was correlated with tumour proliferative potential. Proliferative potential and tumour volume were two independent factors
related to CS invasion. Although VEGF expression was not a direct factor related to CS invasion, it may indirectly play a
role in activation of tumour aggressiveness, which is required in CS invasion.
Our results show that high MR grade adenomas have higher proliferative ability. In order to improve the surgical outcome,
pre-operative medical debulking is indicated, particularly, in such adenomas. 相似文献
68.
Summary Background. Microsurgical selective adenomectomy is the best established method available for the treatment of Cushing's disease. However,
this surgical method warrants still more efforts to improve the results in minute microadenomas. In this paper the authors
evaluate a method of intraoperative cytological investigations during transsphenoidal surgery.
Method. Between January 1997 and September 1999, transsphenoidal surgery was performed in 75 patients with the diagnosis of Cushing's
disease. Fifty-one cases of proven microadenomas were reviewed.
Findings. Of 51 cases, 33 tumors were 3 mm or less in diameter, here after called minute adenomas. In 49 of 51 (96.1%) microadenomas,
adenoma tissue was identified by intraoperative cytological techniques. Postoperatively, only 35 of 51 ACTH-secreting microadenomas
(68.6%) were confirmed by immunostaining methods. This lower percentage was most probably due to the small amount of tissue
obtained. Therefore, in 14 cases (including 12 minute adenomas) the presence of the adenoma was only proven by cytological
preparation and clinical outcome. The sensitivity of cytological preparations in cases of confirmed Cushing's disease was
100%.
Interpretation. The method described here was particularly well suited for the intraoperative discrimination and documentation of minute
adenomas. Cytological preparation appears to be effective in improving the adenoma finding rate and the surgical outcome in
cases of Cushing's disease. 相似文献
69.
70.
尿毒症肾性骨病继发甲状旁腺腺瘤的诊治探讨 总被引:1,自引:0,他引:1
目的 探讨尿毒症肾性骨病继发甲状旁腺腺瘤的诊治方法、疗效及预后。方法 比较罗钙全冲击治疗、甲状旁腺腺瘤切除术两种治疗方式的疗效及预后。结果 罗钙全冲击治疗后 ,患者病情反而加重 ;未行正规治疗 ,疾病进展至晚期或钙化防御者 ,不可逆转 ;行甲状旁腺腺瘤切除术者 ,短期效果良好。结论 甲状旁腺功能亢进应强调早期诊断 ,治疗方案要个体化、正规化。治疗上 ,罗钙全等活性维生素D3 冲击治疗效果不佳 ,甲状旁腺腺瘤切除术短期效果明显 ,且理论上不会导致甲状旁腺功能低下 ,是一种有选择价值的治疗方法 相似文献