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981.
The introduction of ultrahigh-field MRI at 7 tesla (7T) has increased the interest in the use of neuroimaging techniques in clinical research. The high signal-to-noise ratio and profound susceptibility effect at 7T can remarkably improve the spatial resolution and image contrast of structural imaging, susceptibility imaging, and functional imaging techniques, whereas the heating effects of the radio frequency and the inhomogeneities of the local magnetic field can have substantial negative effects on parameter setting, acquisition time, and image quality. T1 prolongation at 7T can improve the enhancement effects of gadolinium agents and the inflow effects on MR angiography and arterial spin labeling. Ultrahigh-field MRI is expected to have a high clinical impact in the near future; however, further technological advances tailored to ultrahigh-field systems as well as the accumulation of scientific evidence will be needed to establish its clinical significance.  相似文献   
982.
目的:探讨青春期前型外阴纤维瘤(prepubertal-type vulva fibroma,PVF)的临床病理特征。方法:分析2例PVF的临床特点,光镜观察组织病理学形态及免疫组织化学特征并复习相关文献。结果:2例分别为8岁和39岁女性,均以大阴唇肿块就诊。肿块均分布在一侧,4~5 cm大。组织学观察病变位于真皮层边界不清,由稀疏的梭形纤维母细胞样的细胞和大量胶原纤维组成,病变向皮下组织延伸,在邻近的脂肪组织及血管簇、神经周围穿插性生长;梭形细胞形态温和无异型、核分裂象未查见。免疫组织化学标记显示:瘤细胞表达波形蛋白、CD34,不表达SMA、desmin、CD99、S-100蛋白、bcl-2,成人局灶表达ER和PR。结论:PVF是一种好发于青春前期幼女或女童外阴的良性间叶性病变,偶可发生于成年人。其发生可能与激素有关并起源于外阴阴道间质细胞,表现为纤维母细胞分化特征。临床有少量病例如切除不净可局部复发,并见可自发性消退病例。  相似文献   
983.
No previous studies have focused on postoperative fat malabsorption in children with choledochal cyst (CC) who undergo cyst excision and Roux-en-Y (RY) hepatico–jejunostomy (HJ), a combination of procedures that can lead to the non-physiological mixture of food and bile juice. To examine the effect of RYHJ with cholecystectomy on the fat absorption ability of children with CC, we estimated postoperative fat-absorption ability using the carbon 13-labeled mixed triglyceride (13C-MTG) breath test. Twelve postoperative children with CC and 12 normal control children were administered 13C-MTG orally and asked to give breath samples at six time points: once before the 13C-MTG ingestion and at five 60-min intervals post-ingestion. Fecal chymotrypsin activity and fecal fat excretion were also measured. The delta value of breath 13CO2 at 3, 4, and 5 h after administration and the 5-h cumulative breath 13CO2 were significantly lower in the CC children than in the controls. There were no significant differences in the fecal chymotrypsin activity or fecal fat excretion of the two groups. Conclusion. Occult fat malabsorption occurs in patients with CC after RYHJ, even in the absence of clinical symptoms or abnormal laboratory data.  相似文献   
984.
OBJECTIVES: An eroded inferior cortex of the mandible detected on dental panoramic radiographs is useful for identifying post-menopausal women with low skeletal bone mineral density (BMD) or osteoporosis. The purposes of this study were to develop a computer-aided diagnosis (CAD) system that automatically determines cortical erosion of the mandible on dental panoramic radiographs and to assess the validation of this CAD system. METHODS: A CAD system was developed based on mathematical morphology for identifying post-menopausal women with low skeletal BMD or osteoporosis, based on World Health Organization criteria, by identifying whether the endosteal margin of mandibular cortical bone was eroded. The sensitivity, specificity, predictive value, accuracy and likelihood for a positive risk result were calculated using dichotomous 2 x 2 tables using 100 panoramic radiographs. RESULTS: For identifying women with low skeletal BMD, the sensitivity and specificity were 76.8% and 61.1%, respectively, the positive and negative predictive values were 90.0% and 36.7%, accuracy was 74.0% and the likelihood for positive risk was 1.96. The respective values for identifying women with osteoporosis were 94.4% and 43.8%, the positive and negative predictive values were 48.6% and 93.3%, respectively, the accuracy was 62.0% and the likelihood for positive risk was 1.68. CONCLUSION: Our results suggest that a CAD system applied to dental panoramic radiographs may be useful for identifying post-menopausal women with low skeletal BMD or osteoporosis.  相似文献   
985.
Abstract   The basics and the technique of magnetic resonance imaging (MRI) for visualizing the neuromelanin present in dopaminergic and noradrenergic nuclei in the substantia nigra pars compacta (SNc) and locus caeruleus (LC) are introduced. Neuromelanin, a black pigment produced during catecholamine synthesis, has paramagnetic T1-shortening effects. Conventional MRI techniques fail to depict the contrast generated by neuromelanin, but neuromelanin-sensitive T1-weighted fast spin echo technique at 3 T allows the direct visualization of the SNc and LC as hyperintense areas. In Parkinson's disease, neuromelanin-related signals from the SNc and LC are diminished, suggesting neuronal degeneration in both the nuclei. In depression and schizophrenia, signals from the LC are reduced while those from the SNc are augmented, suggesting monoamine and dopamine hypotheses, respectively. Neuromelanin-sensitive MRI is a promising technique to elucidate the pathologic or functional changes in the catecholamine neurons of the brain stem that occur in degenerative and psychiatric diseases.   相似文献   
986.
987.

Background

Irinotecan and S-1, an oral fluoropyrimidine composed of tegafur, gimeracil, and oteracil potassium, have demonstrated antitumor activity against advanced gastric cancer. We performed a phase 1/2 study to determine the recommended dose, antitumor activity, and safety of a combination of S-1 and irinotecan in patients with advanced gastric cancer.

Methods

Patients with previously untreated advanced gastric cancer were enrolled. Patients received irinotecan intravenously on days 1 and 15 plus oral S-1 twice daily on days 1–14 of a 28-day cycle. In the phase 1 part, the dose of irinotecan was escalated from 100 mg/m2 to 125 mg/m2 and then to 150 mg/m2.

Results

A total of 24 patients were enrolled. Overall, the median number of treatment cycles per patient was 5.9, and 92% of the patients completed at least two cycles. The overall response rate was 54.2% (13 of 24). The response rates in differentiated and undifferentiated cancer were 56.3% (nine of 16) and 50.0% (four of eight), respectively. Median survival time was 581 days. The maximum tolerated dose of irinotecan was not reached at the highest level. However, grade 4 neutropenia occurred at 125 mg/m2. We concluded that the recommended dose of irinotecan for the present regimen was 125 mg/m2.

Conclusion

Treatment with S-1+irinotecan is considered effective in patients with advanced gastric cancer who have not previously received chemotherapy. A combination of irinotecan and S-1 was well tolerated in patients with advanced gastric cancer and could be given on an outpatient basis.  相似文献   
988.
Results of intestinal transplant are improving in recent years and intestinal transplantation has been established as a therapeutic option for patients with intestinal failure associated with serious parenteral nutrition (PN) -related complications. According to the latest results from the Intestinal Transplant Registry (ITR), reported at the 11th International Small Bowel Transplantation Symposium held in Bologna, Italy in September 2009, the number of transplants was increasing every year and annually rose to 220 transplants per year. Recently one-year graft survival rates achieved more than 80% and most of current survivors had stopped parenteral nutrition and resumed normal daily activities. As of September 2010, 20 intestinal transplants have been performed for 18 patients with intestinal failure in Japan. Eleven living-related segmental intestinal transplants (including 1 combined liver-intestine transplant) were performed, whereas six patients have received intestinal grafts from cadaveric donors. Fourteen of 18 patients are currently alive after transplant. This article reviews current status and future perspective in management of intestinal failure and clinical intestinal transplantation on the basis of our experience and recent publications.  相似文献   
989.
目的研究宫颈癌组织中Raf激酶抑制蛋白(RKIP)和核因子xBp65(NF-κBp65)的表达,探讨二者表达之间的相关性及其与宫颈癌各临床病理因素之间的关系。方法用免疫组织化学方法检测69例宫颈癌组织、37例宫颈上皮内瘤变组织和18例正常宫颈组织的RKIP和NF-κBp65表达,并分析其与宫颈癌临床病理学特征的关系。结果宫颈癌组织中RKIP的表达低于宫颈上皮内瘤变及正常宫颈组织,而NF-κBp65的表达高于宫颈上皮内瘤变及正常宫颈组织,差异有统计学意义(Hc=45.124、38.107,Z=4.309~5.159,P〈O.01);RKIP和NF—κBp65在宫颈癌组织中的表达均与临床分期、有无淋巴结转移及肿瘤分化程度有关(χ^2=5.150~11.917,P〈0.05)。宫颈癌组织中RKIP与NF-κBp65的表达呈显著负相关(r=-0.464,P〈O.01)。结论RKIP表达的减少或缺失与宫颈癌的发生、发展密切相关,RKIP表达的减少或缺失可能通过上调NF—κBp65的表达促进宫颈癌的侵袭和转移。  相似文献   
990.
In Japan, the increasing incidence of β-lactum-resistant Haemophilus influenzae infections is of growing concern. We retrospectively studied whether the prevalence of β-lactamase-negative ampicillin-resistant strains of H. influenzae was influenced by chronic lung diseases. H. influenzae isolates, obtained from patients who were diagnosed with acute or chronic bronchitis, or acute exacerbation of chronic bronchitis in 2005, were studied. In addition to susceptibility testing, polymerase chain reaction (PCR) was performed for the detection of TEM-1 β-lactamase, and Asn526-Lys and Ser385-Thr amino acid substitutions in the ftsI gene encoding penicillin-binding protein-3 (PBP-3). The minimum inhibitory concentration values of β-lactams were found to be increased in isolates from patients with chronic bronchitis who had been repeatedly administered antibiotics. Genetic analysis using PCR suggested that this might be associated with a high frequency of β-lactamase-negative strains with mutations in PBP-3. The presence of β-lactum-resistant strains needs to be considered for patients with chronic bronchitis in whom H. influenzae is isolated as a causative pathogen.  相似文献   
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