全文获取类型
收费全文 | 11216篇 |
免费 | 511篇 |
国内免费 | 77篇 |
专业分类
耳鼻咽喉 | 258篇 |
儿科学 | 480篇 |
妇产科学 | 385篇 |
基础医学 | 1008篇 |
口腔科学 | 408篇 |
临床医学 | 926篇 |
内科学 | 2629篇 |
皮肤病学 | 185篇 |
神经病学 | 679篇 |
特种医学 | 503篇 |
外科学 | 2253篇 |
综合类 | 253篇 |
一般理论 | 3篇 |
预防医学 | 451篇 |
眼科学 | 245篇 |
药学 | 617篇 |
中国医学 | 36篇 |
肿瘤学 | 485篇 |
出版年
2024年 | 7篇 |
2023年 | 107篇 |
2022年 | 228篇 |
2021年 | 390篇 |
2020年 | 202篇 |
2019年 | 274篇 |
2018年 | 322篇 |
2017年 | 236篇 |
2016年 | 366篇 |
2015年 | 423篇 |
2014年 | 529篇 |
2013年 | 610篇 |
2012年 | 774篇 |
2011年 | 779篇 |
2010年 | 467篇 |
2009年 | 409篇 |
2008年 | 768篇 |
2007年 | 868篇 |
2006年 | 849篇 |
2005年 | 779篇 |
2004年 | 663篇 |
2003年 | 538篇 |
2002年 | 476篇 |
2001年 | 86篇 |
2000年 | 79篇 |
1999年 | 66篇 |
1998年 | 60篇 |
1997年 | 41篇 |
1996年 | 51篇 |
1995年 | 29篇 |
1994年 | 21篇 |
1993年 | 22篇 |
1992年 | 23篇 |
1991年 | 20篇 |
1990年 | 24篇 |
1989年 | 31篇 |
1988年 | 20篇 |
1987年 | 19篇 |
1986年 | 18篇 |
1985年 | 18篇 |
1984年 | 8篇 |
1983年 | 11篇 |
1982年 | 6篇 |
1980年 | 6篇 |
1979年 | 7篇 |
1978年 | 8篇 |
1974年 | 5篇 |
1973年 | 9篇 |
1972年 | 7篇 |
1971年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Ozçelik B Serin IS Basbug M Uludag S Narin F Tayyar M 《Human reproduction (Oxford, England)》2003,18(8):1703-1706
BACKGROUND: Our main aim was to investigate the effects of melatonin (ME), possibly the most powerful free-radical scavenger, on the prevention of i.p. adhesion formation in rat uterine horn. Our secondary aim was to determine whether different methods of administration of ME were beneficial. METHODS: Animals were randomly assigned into seven groups, each consisting of 13 rats. Measured serosal injury was created using a standard technique. While control and two sham groups were not given ME, two of the remaining four groups were given a single dose of 10 mg/kg (2 mg) of ME i.p. immediately after injury and 30 min prior to injury respectively. In the two other groups, ME treatment was continued daily for 5 days. All animals were killed 2 weeks after surgery and adhesions were determined and scored by a examiner blinded to the test. RESULTS: The extent, severity and total scores of adhesion were found to be significantly reduced in all of the ME treatment groups when compared with control and sham groups. There were no statistically significant differences between the treatment groups. CONCLUSIONS: This study showed that even single dose ME therapy was effective in the prevention of post- operative i.p. adhesion formation. 相似文献
52.
The use of neuronal nuclear antigen (NeuN) as a reliable neuronal marker in the differential diagnosis of clear cell neoplasms of the central nervous system was determined in a biopsy series of 23 cases. Immunohistochemical analyses were carried out by antisera against neuronal nuclear antigen, synaptophysin, neuron-specific enolase, microtubule-associated protein 2, and glial fibrillary acidic protein. All eight central neurocytomas were characteristically immunolabeled by NeuN. NeuN immunoreactivity was uniformly strong and basically located in the nuclei of neurocytes. Despite this uniform staining pattern of central neurocytomas, 12 cases of oligodendrogliomas and three cases of ependymoma were negative for NeuN. As the diagnostic criteria for central neurocytoma include immunohistochemical and/or ultrastructural evidence for neuronal differentiation, NeuN as a sensitive and specific neuronal marker in formalin-fixed, paraffin-embedded tissues may greatly facilitate the differential diagnosis of central neurocytomas. 相似文献
53.
Vivek Roy Waleska S Pérez Mary Eapen Judith C W Marsh Marcelo Pasquini Ricardo Pasquini Mahmoud M Mustafa Christopher N Bredeson 《Biology of blood and marrow transplantation》2005,11(8):600-608
Patients with Diamond-Blackfan anemia (DBA) who are unresponsive to or intolerant of corticosteroids, experience treatment failure with other treatments, develop additional cytopenias or clonal disease, or opt for curative therapy are often treated with allogeneic bone marrow transplantation. We studied the transplantation outcomes of 61 DBA patients whose data were reported to the International Bone Marrow Transplant Registry between 1984 and 2000. The median age was 7 years (range, 1-32 years). Among 55 patients with available transfusion information, 35 (64%) had received > or =20 units of blood before transplantation. Most patients (67%) received their bone marrow grafts from an HLA-matched related donor. The median time to neutrophil recovery was 17 days (range, 10-119 days) and to platelet recovery was 23 days (range, 9-119 days). Five patients did not achieve neutrophil engraftment. The 100-day mortality was 18% (95% confidence interval, 10%-29%). Grade II to IV acute graft-versus-host disease occurred in 28% (range, 17%-39%) and chronic graft-versus-host disease in 26% (range, 15%-39%). The 3-year probability of overall survival was 64% (range, 50%-74%). In univariate analysis, a Karnofsky score > or =90 and transplantation from an HLA-identical sibling donor were associated with better survival. These data suggest that allogeneic bone marrow transplantation is effective for the treatment of DBA. Transplantation before deterioration of the performance status and from an HLA-identical sibling donor may improve survival. 相似文献
54.
A. H. G. El-Dhaher H. A. Kaouri K. Y. Mustafa 《Medical & biological engineering & computing》1983,21(3):277-284
Analogue recording and plotting on an xy plotter of flow-time signals to produce inaccurate analysis of respiratory data.
To improve on the accuracy of the measurement and reduce the time required for such an analysis a microprocessor-based system
has been developed. The system is designed to be easily operated and requires minimum time from the user. It give the operator
an indication of the drift in the transducer based on calibration at a standard flow rate. The system is interactive with
the user via a visual display terminal. It offers the user full freedom in selecting the parameters to be measured. The displayed
results are calculated from the measured signal and compared with predicted values. Hard copy of the displayed information
can be produced upon user command. The software is flexibly designed to allow for any modification or future expansion. 相似文献
55.
Mustafa Sacar Gokhan Onem Ahmet Baltalarli Suzan Sacar Huseyin Turgut Ibrahim Goksin Vefa Ozcan Serhan Sakarya 《Journal of artificial organs》2007,10(3):177-180
Because slime-forming microorganisms are the major causative agents of graft infections, we aimed to investigate bacterial
adherence in slime-forming and nonslime-forming Staphylococcus aureus and to determine the role of neuraminidase (NANase) on adherence to gelatin-impregnated polyester fiber graft fabric. An
in vitro model was developed to quantitatively measure bacterial adherence to the surface of the graft. The grafts were divided
into two groups – those colonized with slime-forming S. aureus and those colonized with nonslime-forming S. aureus. The grafts were put into sterile tubes and human plasma was instilled and incubated at 37°C to perform fibrin deposition
on the grafts. After 48 h of incubation, grafts were drained and inoculated with slime-forming or nonslime-forming S. aureus in triptic soy broth in the presence or absence of NANase. Following 36 h of incubation at 36°C, grafts were vortexed and
cultured to perform a colony count. Bacterial counts were expressed as total colony-forming units per square centimeter of
graft. Slime-forming S. aureus had greater affinity with the graft compared with nonslime-forming S. aureus (P < 0.05). The adherence of slime-forming S. aureus was impaired by NANase treatment (P < 0.001) but NANase treatment of nonslime-forming S. aureus did not change the adherence to the graft (P > 0.05). These results show that slime plays an important role in the pathogenesis of vascular graft infection. Adherence
of slime-forming S. aureus can be decreased by NANase treatment. This may have implications for the development of neuraminidase-embedded vascular grafts
to diminish biomaterial-related infections. 相似文献
56.
Ihsan H. Ciftci Umit Dundar Zafer Cetinkaya Mustafa Kulac Nilay Kiyildi Aycan Turel Deniz Evcik Vural Kavuncu 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2007,52(1):70-73
The objective of this study was to investigate the incidence and density of Demodex folliculorum in the patients with rheumatoid arthritis (RA). Forty-one patients with RA and twenty-seven age and sex matched healthy controls
were enrolled in this study. Disease Activity Score (DAS 28) was used for the assessment of disease activity. Out of 41 patients,
33 were females and 8 males. The mean disease duration was 10.9 ± 8.2 years. The mean DAS 28 was 3.8 ± 1.2. No statistically
significant differences in the incidence and density of Demodex mites were found between patients with RA and controls. Although immunosuppression is thought to be a risk factor for the
D. folliculorum infestation no such correlations could be found in the 41 immunosuppressed patients with RA, therefore, further studies with
larger groups are needed. 相似文献
57.
Adenosine deaminase activity in serum of patients with hepatitis -- a useful tool in monitoring clinical status. 总被引:2,自引:0,他引:2
Sel?uk Kaya Emel Sesli Cetin Buket Cicioglu Aridogan Salih Arikan Mustafa Demirci 《Journal of microbiology, immunology, and infection》2007,40(4):288-292
BACKGROUND AND PURPOSE: The evaluation of adenosine deaminase (ADA) activity in sera of patients with hepatitis should be considered a useful tool in the monitoring of their clinical status. In this study, we aimed to determine the relationship between viral load, transaminase levels, and serum ADA levels in hepatitis B virus (HBV)- and hepatitis C virus (HCV)-infected patients. METHODS: Seventy three patients with hepatitis B, 71 patients with hepatitis C and 40 healthy individuals were included. Patients with HBV and HCV infections were classified into 3 groups according to viral load. Serum ADA levels were investigated by colorimetric assays. RESULTS: Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and ADA levels of HBV- and HCV-infected patients were higher than those of the control group. These differences were statistically significant for the levels of all enzymes in HCV-infected patients (p<0.05), and all except AST (p>0.05) in HBV-infected patients. ADA levels of HBV-infected patients with high viral loads were higher than those in HBV-infected patients with intermediate and low viral loads, and the difference was detectably significant between patients with high and intermediate viral loads. Evaluation of HCV-infected patients according to viral load showed no statistically significant relationship between viral load and serum ADA, ALT, and AST levels (p>0.05). HBV- and HCV-infected patients with high ALT and AST levels showed statistically significantly higher levels of ADA than patients with normal ALT and AST levels (p<0.001). CONCLUSIONS: We suggest that serum ADA levels are associated more with the level of serum transaminases than viral load in HBV- and HCV-infected patients. In the treatment of patients with hepatitis, serum ADA levels should be considered a useful tool for the monitoring of liver condition. 相似文献
58.
Scorpio DG Akkoyunlu M Fikrig E Dumler JS 《Clinical and diagnostic laboratory immunology》2004,11(5):963-968
Anaplasma phagocytophilum is an obligate intracellular bacterium that infects neutrophils and causes human granulocytic anaplasmosis. Infection induces neutrophil secretion of interleukin-8 or murine homologs and perpetuates infection by recruiting susceptible neutrophils. We hypothesized that antibody blockade of CXCR2 would decrease A. phagocytophilum tissue load by interrupting neutrophil recruitment but would not influence murine hepatic pathology. C3H-scid mice were treated with CXCR2 antiserum or control prior to or on day 14 after infection. Quantitative PCR and immunohistochemistry for A. phagocytophilum were performed and severity of liver histopathology was ranked. Control mice had more infected cells in tissues than the anti-CXCR2-treated group. The histopathological rank was not different between treated and control animals. Infected cells of control mice clustered in tissue more than in treated mice. The results support the hypothesis of bacterial propagation through chemokine induction and confirm that tissue injury is unrelated to A. phagocytophilum tissue load. 相似文献
59.
Tan H Ceviz N Baykal O Büyükavci M Bilici N 《American journal of medical genetics. Part A》2003,(3):266-268
A case with pulmonary atresia/ventricular septal defect associated with port-wine stain and retinal vascular abnormality is reported. Clinical findings were similar to both PHACE syndrome and Sturge-Weber syndrome (SWS). But, the most frequent and well-known features of both syndromes were absent. So, it could not be concluded whether this is a new constellation or an incomplete form of one of the two syndromes. In both situations, presence of a complex congenital heart disease that has not been reported previously makes this case original. 相似文献
60.