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991.
Control of zoonosis implies reduction of infected animal hosts, and the first measure consists of a suitable and accurate detection test. An experimental study for determining the most appropriate antigen (metabolic or somatic) to be used in the detection of the oestrosis (Oestrus ovis) zoonotic myasis by means of immunoenzymatic probes was carried out. A flock of 23 uninfected goats was maintained under field conditions to allow their infection in Sassari (Sardinia, Italy). Caprine were bled monthly and serum samples processed by means of an iELISA. After comparing these results to the chronobiology of O. ovis, we proved that the IgG humoral response against the metabolic antigens increased only during the period of real risk of infestation (when adults fly, from May to September), whereas the absorbances against the somatic products were positive from the beginning of the study (in January, prior to infection). We concluded that the excretory/secretory products are most useful and suitable for the immunodiagnosis of oestrosis in goats, because a direct relation between the development of O. ovis and the IgG humoral response is possible, allowing a more accurate diagnostic.  相似文献   
992.
This article describes the pathological studies of fatal severe acute respiratory syndrome (SARS) in a 73-year-old man during an outbreak of SARS in Taiwan, 2003. Eight days before onset of symptoms, he visited a municipal hospital that was later identified as the epicenter of a large outbreak of SARS. On admission to National Taiwan University Hospital in Taipei, the patient experienced chest tightness, progressive dyspnea, and low-grade fever. His condition rapidly deteriorated with increasing respiratory difficulty, and he died 7 days after admission. The most prominent histopathologic finding was diffuse alveolar damage of the lung. Immunohistochemical and in situ hybridization assays demonstrated evidence of SARS-associated coronavirus (SARS-CoV) infection in various respiratory epithelial cells, predominantly type II pneumocytes, and in alveolar macrophages in the lung. Electron microscopic examination also revealed coronavirus particles in the pneumocytes, and their identity was confirmed as SARS-CoV by immunogold labeling electron microscopy. This report is the first to describe the cellular localization of SARS-CoV in human lung tissue by using a combination of immunohistochemistry, double-stain immunohistochemistry, in situ hybridization, electron microscopy, and immunogold labeling electron microscopy. These techniques represent valuable laboratory diagnostic modalities and provide insights into the pathogenesis of this emerging infection.  相似文献   
993.
Cheng FY  Su CH  Yang YS  Yeh CS  Tsai CY  Wu CL  Wu MT  Shieh DB 《Biomaterials》2005,26(7):729-738
A newly developed non-polymer coated Fe(3)O(4) nanoparticles showing well-dispersion were synthesized using Fe(II) and Fe(III) salt chemical coprecipitation with tetramethylammonium hydroxide (N(CH(3))(4)OH) in an aqueous solution. Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), X-ray photoelectron spectrometer (XPS) and superconducting quantum interference measurement device (SQUID) measurements were employed to investigate the iron oxide properties. The resulting iron oxide particles were manipulated to be as small as 9 nm diameter in size. Based on FT-IR and X-ray photoelectron spectrometer results, it is suggested that the surfaces of the magnetite (Fe(3)O(4)) particles are covered with hydroxide (-OH) groups incorporated with (CH(3))(4)N(+) through electrostatic interaction. The in vitro cytotoxicity test revealed that the magnetite particles exhibited excellent biocompatibility, suggesting that they may be further explored for biomedical applications. NMR measurements revealed significantly reduced water proton relaxation times T1 and T2. The MR images of the nanoparticles in water, serum, and whole blood were investigated using a 1.5 T clinical MR imager. Significant reduction of the background medium signal was achieved in the T2-weighted and the T2*-weighted sequence especially in the serum and whole blood. Combining the advantage of MRI signal contrast, the non-polymer-coated surface chemistry for distinct bioconjugation and the homogenous nanometer size for better controlled biodistribution, these preliminary experiments demonstrated the potential of the as-synthesized magnetite material in functional molecular imaging for biomedical research and clinical diagnosis.  相似文献   
994.
SACCHACHITIN membranes, prepared from the waste residue of the fruiting body of Ganoderma taugae, were used in our previous study to enhance skin wound healing in animal models. In the present study, the effects of the membrane on the growth of keratinocytes and the activity of matrix metalloproteinases (MMPs), as well as on the healing of skin wounds in humans, were estimated. Fresh human foreskin was employed as the source of the keratinocyte culture, and a modified keratinocyte-SFM medium supplemented with 0.2 ng/mL of recombinant epidermal growth factor and 30 microg/mL bovine pituitary extract was used to enhance the successful growth of keratinocytes under an atmosphere of 5% CO2, at 37 degrees C. The results indicated that 0.01% SACCHACHITIN enhanced the proliferation of keratinocytes in the culture on the fourth and fifth days, and cells showed neither morphological alteration nor disordered proliferation. This evidence clearly indicated that SACCHACHITIN was not cytotoxic to and was safe for the growth of keratinocytes. Thus, SACCHACHITIN might play a positive role in the proliferation and differentiation of keratinocytes around wounds and in accelerated wound healing of epidermal tissue. In addition, microscopic observations during the growth of keratinocytes showed that normal proliferation and differentiation took place along the margin of the SACCHACHITIN membrane. This indicates that SACCHACHITIN is possibly cytocompatible with keratinocytes. Electrophoretic analysis and inhibition tests for the binding effect of SACCHACHITIN on MMPs showed that SACCHACHITIN reduced MMPs in extracellular matrix degradation and facilitated establishment of an extracellular matrix around wounds; these effects resulted in rapid wound healing. SACCHACHITIN was used as a skin dressing for patients who had skin chronicle ulcer, which had not healed for over 7 months. Preliminary clinical observations showed that the wound improved and began to heal. An analysis of MMPs by ELISA in tissue of the wound indicated a significant decrease in MMP levels.  相似文献   
995.
大鼠松果体衰老的形态学研究   总被引:2,自引:0,他引:2  
目的 探讨松果体形态结构的衰老性变化,为进一步研究松果体与衰老的关系提供形态学基础。方法 随机选取3月龄和34月龄SD大鼠10只分别作为青年组和老年组,用光镜和电镜结合形态计量学分法分析松果体细胞和神经胶质细胞密度及其指数;松果体细胞线粒体的Vv、Sv、Nv,高尔基器的Vv、Sv、粗面内质网的Sv、溶酶体的Vv;松果体神经终末的Vv及其线粒体的Vv、Sv、Nv、小颗粒囊泡的NA。结果 与青年组相比,老年组松果体细胞核形状不规则,核膜皱褶增多和加深。细胞浆内粗面内质网减少,排列紊乱,分散,脱颗粒明显;线粒体结构不清、肿胀、嵴断裂、消失、空泡化等。老年组松果体细胞密度比青年组减少,而神经胶质细胞密度增加,差异有高度显著性(P<0.01)。老年组神经胶质细胞指数比青年组高(P<0.01)。老年线粒体Vv与青年组无差别,但老年组线粒体Sv、Nv均比青年组减少(P<0.01)。老年组高尔基器的Vv、Sv均比青年组减少(P<0.01);老年组粗面内质网Sv比青年组减少,而老年组溶酶体Vv比青年组增加(P<0.01);老年组神经终末Vv比青年组减少(P<0.01);老年组神经终末中小颗粒囊泡NA比青年组减少(P<0.01);老年组线粒体Sv、Nv比青年组减少(P<0.05),两组神经终末中线粒体Vv无差别(P>0.05)。结论 老年大鼠松果体已发生衰老性变化,这可能与机?  相似文献   
996.
目的探讨维生素E(VitaminE,VE)对慢性镉中毒小鼠睾丸生精细胞损伤的保护作用。方法3月龄昆明种雄性小鼠60只,随机分3组:镉组(每次CdCl22mg/kg,皮下注射,每周2次,共3个月),VE组(染镉同时给VEl0mg·kg-1·d-1,灌胃)和正常对照组(注射等量生理盐水),用光镜、电镜观察生精细胞形态变化,并对精原细胞和精子的超微结构进行立体定量分析。结果(1)与正常对照组比较,镉组小鼠睾丸均受损,根据受损程度可分为轻、中、重3型;精原细胞胞核和精子头内细胞核的平均截面积、平均体积和平均表面积等形态参数值均显著缩小(P<0.05);(2)VE组:大部分小鼠睾丸的形态结构接近正常,仅少部分小鼠的睾丸受到轻、中型损伤;精原细胞胞核和精子头内细胞核的平均截面积、平均体积和平均表面积等形态参数值与正常对照组的相应值接近,无显著性差异(P>0.05)。结论VE对镉引起的小鼠生精细胞形态的损伤有一定保护作用。  相似文献   
997.
Su FC  Chu TC  Wai YY  Wan YL  Liu HL 《Medical physics》2004,31(1):154-160
Functional magnetic resonance imaging (fMRI) based on both perfusion and blood oxygenation level-dependent (BOLD) contrasts has been widely applied in spatiotemporal mapping of the human brain function. Temporal resolving power of fMRI is limited by the smoothed hemodynamic response function dispersed from the neuronal activity. In this study, temporal modulation transfer functions were utilized to quantify the resolving powers of perfusion and BOLD fMR signals in time domain. The impulse response function was determined using brief visual stimulations and event-related image acquisition schemes. An important feature of arterial spin labeling techniques is that quantitative perfusion and BOLD signals could be simultaneously acquired. This simultaneous BOLD response may arise from signals that are more proximal to capillary beds, and its temporal resolution may be different from that of the typical BOLD response. Therefore, we assessed and compared the temporal resolving capabilities of perfusion, simultaneous BOLD, and the typical BOLD response obtained from the gradient echo EPI pulse sequence. Full-width-at-half-maximums of perfusion and simultaneous BOLD measurements were significantly smaller than that of BOLD ones (4.3+/- 0.6 s vs 5.5 +/- 0.9 s, p<0.02 and 4.7 +/- 1.3 s vs 5.5 +/- 0.9 s, p<0.01, respectively). The corresponding temporal resolving powers of perfusion and simultaneous BOLD signals were statistically better than that of BOLD signals (0.23 +/- 0.03 Hz vs 0.17 +/- 0.02 Hz, p<0.01 and 0.21 +/- 0.04 Hz vs 0.17 +/- 0.02 Hz, p<0.01, respectively). Our results showed that the typical BOLD response was significantly smoothed from the perfusion response, thus resulting in a degraded temporal resolving power. However, results from the simultaneous BOLD and perfusion measurements were not significantly different. Biophysical implications of the experimental outcomes were further investigated using a computer simulation based on the Balloon model. By fitting the measured data into the model, an apparently longer transit time was obtained for the typical BOLD signal (1.7 s), comparing to that for the simultaneous BOLD one (1.2 s). Therefore, the simultaneous BOLD signal was regarded as less susceptible to the variations from local draining veins. Combining the simulation result with the significantly discrepant resolving powers between the two BOLD signals, we speculated that the blurred effects from large vessels played a predominant role that further reduced the temporal resolution of the BOLD-based fMRI from the perfusion response.  相似文献   
998.
Liu JH  Okazaki K  Mweene A  Shi WM  Wu QM  Su JL  Zhang GZ  Bai GR  Kida H 《Virus genes》2004,29(3):329-334
The hemagglutinin (HA) genes of 12 H9N2 influenza virus strains isolated from chickens in Mainland China during the period 1995–2002 were genetically analyzed. All the isolates possessed the same amino acid motif -R-S-S-R/G-L- at the cleavage site of HA. Except for the conserved amino acids, as is the case in the other avian influenza viruses, located in the receptor binding site, all of the 12 isolates possessed N at amino acid position 183; A, T, or V at position 190; K at position 137, whereas the representative strains of the other lineage (except Dk/HK/Y280/97-like lineage) virus of H9N2 viruses had H, E, and R at these positions respectively. These could be considered as the partial molecular markers of the H9 viruses isolated from chickens in Mainland China. Phylogenetic analyses showed HA genes of these isolates belonged to that of A/duck/Hong Kong/Y280/97-like virus lineage. No A/quail/Hong Kong/Gl/97-like virus was found in chicken, population since the outbreak of H9N2 influenza in Mainland China in 1992. The available evidence indicates that HA genes of H9 influenza virus circulating in Mainland China during the past years were well conserved.  相似文献   
999.
An anaplastic large cell lymphoma that was negative for Epstein-Barr virus and positive for Ki-1 (CD30) presented as a polypoid scalp mass in a 56-year-old man 16 years after renal transplantation. The lymphoma was of the CD4+ cytotoxic T-cell lineage, and the tumor cells also expressed CD56. Despite reduction in the dose of immunosuppression and localized radiotherapy, the tumor had rapidly progressed to involve the soft tissue of the right hand. Systemic chemotherapy induced complete regression of the soft tissue lesion. This case illustrates that posttransplant primary cutaneous CD30+ anaplastic large cell lymphomas may assume an aggressive clinical course but can still be controlled by systemic chemotherapy.  相似文献   
1000.
Observations of impaired glucose regulation in schizophrenia are long-standing, although their pathological and etiological significance is uncertain. One approach to the issue that minimizes environmental variables (e.g., medication and diet) is to determine whether genes related to glucose regulation show genetic linkage to schizophrenia. We examined the potential role of glucose metabolism in schizophrenia through a genome scan of affection status in schizophrenia and an empirical method for deriving P-values. Data were utilized from the NIMH Genetics Initiative for Schizophrenia dataset, which comprises a total sample consisting of 71 pedigrees containing 218 nuclear families and 987 individuals. A genome scan with 459 markers spaced at an average of 10 cM intervals was conducted using the linkage analysis program Genehunter separately for European- and African-American groups. Enzymes that regulate glycolysis were identified and the genes regulating these enzymes were located through the Online Mendelian Inheritance in Man (OMIM) website. The focus in this study was on genes located near previously reported schizophrenia susceptibility regions. The genome-wide significance of these genes to schizophrenia was assessed using permutation testing. When results were adjusted for multiple testing within and across ethnic groups, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 2 (PFKFB2; chromosome 1q32.2) achieved genome-wide significance (P = 0.04). In addition, hexokinase 3 (HK3; chromosome 5q35.3) was also suggestive of linkage (P = 0.09). For the European-American sample, PFKFB2 (1q32.2), hexokinase 3 (HK3; 5q35.3), and pyruvate kinase 3 (PK3; chromosome 15q23) achieved significance at the 0.05 level. None of the genes showed significance in the African-American sample. Our results provide further support for the view that genes that regulate glucose metabolism may also influence susceptibility to schizophrenia. More generally, they support the view that relationships between glucose dysregulation and schizophrenia are inherent to the disorder, and are not merely epiphenomena related to medication or other treatment factors.  相似文献   
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