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91.
Lanari M Papa I Venturi V Lazzarotto T Faldella G Gabrielli L Guerra B Landini MP Salvioli GP 《Journal of medical virology》2003,70(4):628-632
Human herpesvirus 6 (HHV 6) has neurotropic and neuroinvasive properties. The virus has been found in the cerebrospinal fluid of many children with aseptic meningoencephalitis. Intrauterine transmission has been documented by HHV 6 DNA detection in cord blood specimens of apparently healthy newborns and in fetuses following spontaneous abortions. A patient is described with early neonatal afebrile seizures resulting from a congenital HHV 6 variant B infection disclosed by repeated detection of viral genome by polymerase chain reaction (PCR) in cerebrospinal fluid in the first days of life. At follow-up, magnetic resonance imaging (MRI) studies disclosed hyperintensities in the periventricular white matter and basal ganglia, associated with cerebral atrophy. Further follow-up at 18 months revealed poor neurological outcome with mild neurodevelopmental retardation, strabismus and hypertonia of legs. This report provides evidence of neurological involvement after HHV 6 vertical transmission, and the association with neurological sequelae. 相似文献
92.
Massa O Iafusco D D'Amato E Gloyn AL Hattersley AT Pasquino B Tonini G Dammacco F Zanette G Meschi F Porzio O Bottazzo G Crinó A Lorini R Cerutti F Vanelli M Barbetti F;Early Onset Diabetes Study Group of the Italian Society of Pediatric Endocrinology Diabetology 《Human mutation》2005,25(1):22-27
Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes. 相似文献
93.
V. Houdouin S. Bonacorsi P. Bidet E. Bingen 《Clinical microbiology and infection》2007,13(12):1207-1210
The susceptibility of 136 Escherichia coli isolates from cases of neonatal meningitis to amoxycillin, ceftriaxone, nalidixic acid, ciprofloxacin and gentamicin was determined in relation to the carriage of virulence factors and phylogenetic group. Only amoxycillin and nalidixic acid resistance was observed (40% and 3%, respectively). Nalidixic acid resistance alone was associated with non-virulent phylogenetic group A (50% vs. 6% of susceptible isolates; p 0.03). No difference in virulence was observed between two representative nalidixic acid-susceptible virulent group B2 isolates and their nalidixic acid-resistant derivatives in a rat model of neonatal meningitis, suggesting that nalidixic acid resistance does not affect the virulence of E. coli strains causing meningitis. 相似文献
94.
Expression of oncogene products, anti-oncogene products and oncofetal antigens in intraductal papillary-mucinous neoplasm of the pancreas 总被引:1,自引:0,他引:1
A few previous studies have demonstrated the expression or mutations of oncogenes and anti-oncogenes as well as that of oncofetal antigens in intraductal papillary-mucinous neoplasm of the pancreas. In this study, we have investigated the immunohistochemical expression of oncogene (ras and c-erbB-2) and anti-oncogene (p53 and retinoblastoma [Rb]) products and oncofetal antigens (CEA, CA19-9 and DUPAN-2) in nine such tumours of the pancreas. In normal pancreas (5 cases), the Rb gene product and CA19-9 were expressed in all cases, while ras and c-erbB-2 gene products, p53 protein, CEA and DUPAN-2 were not expressed. In intraductal papillary-mucinous tumours (n = 9), ras, c-erbB-2, p53 and Rb gene products were present in 4/9 (44%), 7/9 (78%), 0.9 (0%) and 6/9 (67%) cases, respectively. CEA, CA19-9 and DUPAN-2 were expressed in 8/9 (89%), 9/9 (100%) and 2/9 (22%) cases respectively. In invasive ductal adenocarcinoma of the pancrease (7 cases), ras, c-erbB-2, p53 and Rb gene products were expressed in 3/7 (43%), 6/7 (86%), 2/7 (29%) and 3/ & (43%) cases respectively. CEA, CA19-9 and DUPAN-2 were expressed in 7/7 (100%), 7/7 (100%) and 6/7 (86%) cases, respectively. The extent and intensity of the expression of these antigens was greater in invasive ductal adenocarcinomas. These data suggest that activation of ras and c-erbB-2 oncogenes and inactivation of Rb anti-oncogene may contribute to the development and progression of intraductal papillary-mucinous tumours of the pancreas and that there is neo-expression of CEA and DUPAN-2 during the development and progression of these tumours. 相似文献
95.
Jocelyne Daigneault Gervais Aubin Fernand Simard Marc De Braekeleer 《Clinical genetics》1991,40(4):298-303
Cystic fibrosis (CF) is an autosomal recessive disorder with a prevalence at birth estimated at 1/2000-1/2500 livebirths in Caucasian populations. Some 127 CF individuals are known in Saguenay-Lac-St-Jean (SLSJ), a geographically isolated region of Quebec. The prevalence at birth was estimated at 1/902 live borns, and the carrier rate was estimated at 1/15 inhabitants in the SLSJ region. The mean inbreeding coefficient was only slightly elevated in the CF group compared with three control groups, and was due to remote consanguinity. The mean kinship coefficient was 2.4 times higher in the CF group than in the control groups. In SLSJ region, the places of origin of the CF individuals and their parents did not show a clustered nonuniform distribution. Endogamy was not higher in the CF group than in control groups. 相似文献
96.
静态与动态下脱细胞猪主动脉瓣种植人成纤维细胞初步研究 总被引:1,自引:0,他引:1
目的 探索在脱细胞猪主动脉瓣膜材料上种植人成纤维细胞的方法与效果;材料和方法 采用在脱细胞猪主动脉瓣膜材料上静态与动态种植人成纤维细胞,并对其结果进行比较研究。结果 静态种植不能在猪主动脉瓣叶的两侧形成完整的单层人成纤维细胞融合层;而经过动态种植,在一定条件下可以在猪主动脉瓣叶两侧形成完整的单层人成纤维细胞融合层;结论 动态种植较之静态种植易达到形成完整均匀的细胞种植效果。 相似文献
97.
Pinborg A Lidegaard O la Cour Freiesleben N Andersen AN 《Human reproduction (Oxford, England)》2005,20(10):2821-2829
BACKGROUND: Spontaneous reductions are a possible cause of the increased morbidity in IVF singletons. The aim of this study was to assess incidence rates of spontaneous reductions in IVF/ICSI twin pregnancies and to compare short- and long-term morbidity in survivors of a vanishing co-twin with singletons and born twins. METHODS: We identified 642 survivors of a vanishing co-twin, 5237 singletons from single gestations and 3678 twins from twin gestations. All children originated from pregnancies detected by transvaginal sonography in gestational week 8. By cross-linkage with the national registries the main endpoints were prematurity, birth weight, neurological sequelae and mortality. RESULTS: Of all IVF singletons born, 10.4% originated from a twin gestation in early pregnancy. Multiple logistic regression analyses adjusted for maternal age, parity and ICSI treatment showed for birth weight <2500 g an odds ratio (OR) of 1.7 [95% confidence interval (CI) 1.2-2.2] and for birth weight <1500 g OR 2.1 (95% CI 1.3-3.6) in singleton survivors of a vanishing twin versus singletons from single gestations; corresponding figures were seen for preterm birth. This increased risk was almost entirely due to reductions that occurred at >8 weeks gestation. We found no excess risk of neurological sequelae in survivors of a vanishing co-twin versus the singleton cohort; however, OR of cerebral palsy was 1.9 (95% CI 0.7-5.2). Furthermore, we observed a correlation between onset of spontaneous reduction, i.e. the later in pregnancy the higher the risk of neurological sequelae (r = -0.09; P = 0.02). Adjusted OR of child death within the follow-up period was 3.6 (95% CI 1.7-7.6) in the survivor versus the singleton cohort. CONCLUSIONS: One in 10 IVF singletons originates from a twin gestation. Spontaneous reductions that occur at >8 weeks gestation are one of the causes for the higher risk of adverse obstetric outcome in IVF singletons. 相似文献
98.
家猪心脏纤维支架的大体解剖 总被引:1,自引:1,他引:1
目的 观察猪心纤维支架 ,为猪心的研究和比较解剖学积累资料。方法 取甲醛固定后的猪心2 7例 ,液态塑料浸渍的塑化猪心 5例 ,解剖显示纤维支架后用游标卡尺进行观测。结果 猪心左纤维三角的三边分别平均为 17 4 1± 1 99mm、18.96± 3.2 6mm和 17.6 4± 2 .4 4mm ;右纤维三角三边分别为 15 .83± 2 .11mm、16 .19± 1.94mm和 2 0 .96± 2 .6 2mm ;二尖瓣环、三尖瓣环的周长平均为 73.0 0± 9.71mm ,6 8.89±7.2 4mm ;主动脉瓣环和肺动脉瓣环直径分别为 18.4 4± 2 .89mm和 16 .0 3± 2 .6 3mm ;猪Todaro腱呈扁带状 ,走行部位较深 ,且分支较人心多 ,长度为 2 0 98± 4 2 0mm。结论 猪心纤维支架与人类形态结构相似 ,但瓣环周长和Todaro腱形态有一定差别。 相似文献
99.
目的 观测家猪心脏三尖瓣复合体 ,为家猪心脏研究和心脏移植积累资料。方法 甲醛固定的家猪心脏 35例 ,大体解剖并观测三尖瓣复合体。结果 家猪心脏三尖瓣复合体由瓣环、瓣膜、腱索和乳头肌构成 ,瓣环周长为 70 75± 8 4 5mm ,前瓣、后瓣、隔侧瓣、前隔连合、前后连合、后隔连合的高度分别为 14 5 8±2 6 4、14 16± 2 5 0、12 84± 2 37、6 2 9± 1 97、6 86± 1 0 1、6 5 1± 1 36mm。前隔连合、前后连合、后隔连合的宽度分别为 6 4 0± 1 5 4、6 78± 1 2 3、6 4 3± 1 4 6 ;前乳头肌起始 ,腱索附着于前瓣、后瓣和前后连合的条数分别为 3 0 0± 0 97、3 0 9± 1 0 9、2 4 4± 1 16 ;后乳肌起始 ,腱索附着于后瓣、隔侧瓣和后隔连合的条数分别为 2 6 0± 0 6 9、3 0 9± 1 6 3、1 14± 0 4 3。隔侧乳头肌起始 ,附着于前瓣、隔侧瓣、前隔连合的腱索条数分别为1 71± 0 6 7、2 37± 1 2 6、0 94± 0 4 2。结论 家猪心脏三尖瓣复合体中各结构与人类相似 ,但大小有一定差异。 相似文献
100.
G. Paraskevas B. Papaziogas C. Lazaridis P. Gigis T. Papaziogas 《Surgical and radiologic anatomy : SRA》2002,23(6):437-442
Abstract: Three cases (two male, one female) of annular pancreas are presented, which were found and operated on within the last three decades. Diagnosis was made using imaging techniques, especially ultrasonography and computed tomography. In two cases there was incomplete obstruction, while in the other obstruction was complete. It is characteristic that in the case of complete obstruction the annular portion of the pancreas attached to a circular band of connective tissue, while in the two cases of incomplete obstruction there was a complete ring of pancreatic tissue. In all cases surgical intervention was needed in order to create a bypass. In the first case gastroenterostomy and truncal vagotomy was performed, in the second latero-lateral duodeno-jejunostomy and in the third latero-lateral antropyloroduodeno-jejunostomy. The embryology and morphology of the annular pancreas, the morphology of its duct system, diagnosis, differential diagnosis and the surgical treatment of this rare condition are reviewed. 相似文献