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81.
Human papillomavirus types in anogenital warts of children   总被引:3,自引:0,他引:3  
Tissue from anogenital warts of 25 children, 10 of whom were suspected of being victims of sexual abuse, was investigated by dot blot and Southern blot techniques for human papillomavirus (HPV) types. HPV DNA was detected in 22 children, two of whom had double infections. The genital HPV types 6 and/or 11 were detected in 20 children, and in three children other HPV types were found. One had HPV 18 (as well as 11); in a second child a possible skin type, HPV 2, was detected; and the third child was infected with an unidentified type. In three cases genital wart material was available from one of the parents, and in all three the HPV type was the same as that of the child. For nine other children one or both parents were reported to have genital warts. The source of infection appeared to be the adult genital tract, but sexual contact might not be the only means of transmission.  相似文献   
82.
Development of an effective preventive or therapeutic vaccine against HIV-1 is an important goal in the fight against AIDS. Effective virus clearance and inhibition of spread to target organs depends principally on the cellular immune response. Therefore, a vaccine against HIV-1 should elicit virus-specific cytotoxic lymphocyte (CTL) responses to eliminate the virus during the cell-associated stages of its life cycle. The vaccine should also be capable of inducing immunity at the mucosal surfaces, the primary route of transmission. Recombinant Bacille Calmette-Guérin (BCG) expressing viral proteins offers an excellent candidate vaccine in view of its safety and ability to persist intracellularly, resulting in the induction of long-lasting immunity and stimulation of the cellular immune response. BCG can be administered orally to induce HIV-specific immunity at the mucosal surfaces. The immunogenicity of four recombinant BCG constructs expressing simian immunodeficiency virus (SIV) Gag, Pol, Env, and Nef proteins was tested in rhesus macaques. A single simultaneous inoculation of all four recombinants elicited SIV-specific IgA and IgG antibody, and cellular immune responses, including CTL and helper T cell proliferation. Our results demonstrate that BCG recombinant vectors can induce concomitant humoral and cellular immune responses to the major proteins of SIV.  相似文献   
83.
The relative roles of serum factors required for opsonization of type XIV Streptococcus pneumoniae were investigated by means of luminol-enhanced chemiluminescence (CL), bactericidal, and immunofluorescence assays employing adult sera containing high (>1,000 ng of antibody nitrogen per ml) or low (<200 ng of antibody nitrogen per ml) antibody concentrations as determined by radioimmunoassay. Specific antibody concentration correlated directly with both total and heat-labile CL activity (P < 0.005) and with the bactericidal index (P < 0.05) at a serum concentration of 10%. The importance of specific antibody as an opsonin was confirmed by the abolition of CL activity and immunoglobulin immunofluorescence observed after absorption of heated sera with type XIV pneumococcal cells and by the dose response in CL and bactericidal activity observed with the addition of immunoglobulin G to hypogammaglobulinemic serum. A role for the classical complement pathway in opsonization was indicated by significantly greater CL integrals for high-antibody sera than for low-antibody sera depleted of factor D and by the bactericidal activity noted for untreated, but not magnesium ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid-chelated low-antibody sera. The alternative pathway contributed more than half of the CL activity of both high- and low-antibody sera. However, after magnesium ethylene glycol-bis(β-aminoethyl ether)-N,N-tetraacetic acid chelation, only sera with high antibody concentrations or agammaglobulinemic serum reconstituted with immunoglobulin G with high specific antibody levels supported significant bactericidal activity. Therefore, type-specific antibody and complement promote opsonization of type XIV S. pneumoniae, and this may occur via either complement pathway. These results suggest that CL is a suitable tool to delineate serum factors and their contribution to opsonization, but results must be related to other functional assays.  相似文献   
84.
EphA2 is a transmembrane receptor tyrosine kinase that is overexpressed in many carcinomas. Specific targeting of EphA2 with monoclonal antibodies is sufficient to inhibit the growth, migration and invasiveness of aggressive cancers in animal models. Using immunohistochemical analyses, we measured the expression of EphA2 in prostatic adenocarcinoma, high-grade prostatic intraepithelial neoplasia, and adjacent benign prostate tissue from ninety-three radical prostatectomy specimens. These results were related to multiple clinical and pathologicalcharacteristics. The fraction of cells staining positively with EphA2 in benign prostatic epithelium (mean, 12%) was significantly lower than that in high-grade prostatic intraepithelial neoplasia (mean, 67%, P < 0.001) and prostatic adenocarcinoma (mean, 85%, P < 0.001). Moreover, the intensity of EphA2 immunoreactivity in prostatic adenocarcinoma was significantly higher than in benign prostatic tissue (P < 0.001) or high-grade prostatic intraepithelial neoplasia (P < 0.001). Benign prostatic epithelium showed weak or no immunoreactivity for EphA2 in all cases examined. Whereas EphA2 immunoreactivity related to neoplastic transformation, it did not correlate with other clinical and pathological parameters examined. Our data suggest that EphA2 levels increase as prostatic epithelial cells progress toward a more aggressive phenotype. Progressively higher levels of EphA2 in high-grade prostatic intraepithelial neoplasia and prostatic carcinoma are consistent with recent evidence that EphA2 functions as a powerful oncogene. Moreover, the presence of high levels of EphA2 in these cells suggests opportunities for prostate cancer prevention and treatment.  相似文献   
85.
We determined whether there is an association between tumor necrosis factor-alpha (TNF-alpha), undernutrition [prealbumin (PA) <160 mg/L, retinol binding protein (RBP) <30 mg/L], disease stage, outcome (death or survival), and race in children with leukemia. TNF-alpha, PA, and RBP were measured in 52 patients (0.8 to 17 years old): 18 African Americans, 34 whites; 27 newly diagnosed (ND), and 25 in clinical remission (CR). Mean levels of TNF-alpha were higher in patients than in 46 healthy children (p < 0.05), but were not different between ND and CR groups. Mean acute phase proteins (APP) were different among groups: ND > CR > controls (p < 0.05). Mean levels of PA and RBP were lower in patients than in controls (p < 0.051, and tended to be higher in CR than in ND patients. African-American patients had lower concentrations of TNF-alpha, PA, and RBP but higher APP than white patients (p < 0.05). CR patients and African-American patients who died tended to have higher levels of TNF-alpha and APP, but lower PA and RBP than those who survived. A higher percentage of ND African Americans (45%) than of ND whites (13%) died. Results suggest that undernutrition and inflammation in CR patients and African Americans were associated with poor survival, and that ND African Americans have a poorer outcome than whites independently of TNF-alpha levels.  相似文献   
86.
The development of an M antibody capture ELISA for rubella IgM   总被引:2,自引:0,他引:2  
An M antibody capture enzyme-linked immunosorbent assay for rubella IgM was developed. The enzyme label was prepared from a monoclonal antibody raised against rubella haemagglutinin (Tedder et al., 1982). Paired sera from acute rubella infections and vaccines as well as sera from blood donors, antenatal patients and patients whose sera contained rheumatoid factor and patients with acute non-rubella infections were tested by this method.  相似文献   
87.
The primary purpose of this study was to identify the mammalian tissue cultures which were most suitable for investigations of the cytopathogenicity of Trichomonas vaginalis. A recently isolated strain of the organism was inoculated into 15 different tissue cultures which were maintained in an appropriately modified growth medium. Proliferation of the protozoon was accompanied by the progressive disintegration of cell culture monolayers. Initial focal lesions consisting of detached cells and an accumulation of trichomonads gradually enlarged until the entire monolayer was disrupted. When judged by the size of the inoculum required to obtain this effect, differences among the tissue cultures were noted. An inoculum of approximately 10(3) viable trichomonads was sufficient to completely disrupt monolayers of HeLa 229, HeLa, McCoy, HEp-2, and RK-13 cells. To obtain a comparable effect with other cells, 10- to 100-fold higher levels of inoculum were required. Polyethylene glycol concentrates from culture filtrates contained a cell-detaching factor (CDF) which caused detachment and clumping of susceptible cells. Freshly seeded cells in growth medium containing CDF failed to form a monolayer. Aggregates of cells maintained for up to 1 week in the presence of CDF remained viable and formed a monolayer after being washed and suspended in normal growth medium. The activity of the CDF was not lost during 1 week of contact with the cells. The CDF may contribute to the pathogenicity mechanisms of T. vaginalis.  相似文献   
88.
Pathogenic germline variation in the microRNA processing gene DICER1 gives rise to an autosomal dominant, tumor‐predisposition disorder. Conditional deletion of Dicer1 in murine dental epithelium shows that it controls tooth patterning, size, number, and shape. The human dental phenotype of people with germline pathogenic variation in DICER1 is unknown. DICER1‐carriers (n = 57) and family controls (n = 55) were evaluated at the NIH Clinical Center dental clinic as part of a comprehensive medical evaluation. Digital panoramic radiographs, bite‐wing radiographs, and oral photographs were collected. A single observer, blind to DICER1 status, reviewed the dental records and determined the presence or absence of 11 dental characteristics as described in the clinic notes, radiographs, or oral photographs. Subjective phenotypes were reviewed on radiographs by two examiners (blind to DICER1 status) for the presence or absence of the dental characteristics to reduce inconsistencies. By simple association, bulbous crown, periodontitis, and taurodontism were all significant (p < .05). Logistic regression with chi‐square maximum likelihood estimates showed that bulbous crown and periodontitis remained significant. Recognition of these phenotypes may aid identification of individuals and families at risk for DICER1‐associated neoplasms. These findings may also guide dental care for individuals with germline DICER1 pathogenic variation.  相似文献   
89.
The calmodulin (CaM) content of intact and chemically skinned strips of rat caudal artery was measured using a125I-CaM radioimmunoassay. The total CaM measured following homogenization of arterial tissue with EGTA and EGTA/Triton X-100 was 2.58 mol/kg wet tissue. Based on a smooth muscle volume of 40%, this value corresponds to a cellular CaM concentration of 6.5 M. Approximately 97% of total CaM was soluble and approximately 3% was EGTA-nonextractable. Permeabilization of the plasmalemma with 0.15 mg/ml saponin or 0.5% Triton X-100 caused significant detergent-dependent loss of CaM. At the end of a 1 h skinning period, tissues exposed to saponin lost 30% of total CaM. By comparison, tissues skinned under the same conditions with Triton X-100 lost 50%. During a subsequent 4h exposure to relaxing solution, total tissue CaM continued to decline. The exponential loss over the 5h period was described by a first order model having diffusible and nondiffusible CaM components. The diffusible CaM component of saponin skinned tissue (59%) was significantly less than the diffusible component of those skinned with Triton X-100 (88%); however, the rate coefficients for CaM diffusion (0.78 h–1 and 0.91 h–1, respectively) did not statistically differ. The nondiffusible component of CaM was significantly larger in saponin treated strips (42%) than in Triton X-100 permeabilized tissue (12%). Arterial strips skinned with Triton X-100, which were subsequently exposed to relaxing solution for up to 22 h, lost significantly more CaM than those retained in Triton X-100 skinning solution for a comparable duration These studies demonstrate the diffusion of CaM from detergent skinned arterial strips and characterize the time course of that loss.  相似文献   
90.
Cholesterol embolism causing bleeding gastric ulcers   总被引:1,自引:0,他引:1  
Two cases of atheromatous embolism of the small arteries of the stomach are reported. Insofar as has been ascertained, they are the first reported cases in the literature which presented symptoms of severe gastric bleeding and were found to have bleeding gastric ulcers on endoscopy. Both patients were successfully treated surgically, and their ulcers were found to be secondary to small arteriolar occlusions owing the atherosclerotic embolization. Awareness of clinicians as well as pathologists of this phenomenon in elderly males with symptoms of abdominal pain and other upper gastrointestinal symptoms unrelated to the ingestion of food is stressed. Pathophysiology of atherosclerotic emboli is also discussed.  相似文献   
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