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61.
Molecular epidemiological studies of hepatitis C virus (HCV) in the Caribbean may help to specify the origin and spread of HCV infection. Indeed, the Caribbean population is intermixed from European and African origins and geographically close to the American continent. We characterized HCV genotypes in the Caribbean island of Martinique. HCV genotypes were analyzed by sequencing or reverse hybridization in the 5' noncoding region (5'NC) in 250 HCV-monoinfected and 85 HCV-human immunodeficiency virus (HIV)-coinfected patients. In addition, sequencing in the nonstructural 5B (NS5B) gene was required to determine the subtype or to perform phylogenetic analysis in selected samples. Genotypes 1 to 6 were found, respectively, in 84.4, 6.8, 5.2, 2.8, 0.4, and 0.4% of 250 HCV-monoinfected patients and in 71.7, 7.1, 15.3, 5.9, 0, and 0% of 85 HCV-HIV-coinfected patients. HCV-1b was found in 66.4% of the HCV-monoinfected patients and was associated with blood transfusion, whereas HCV-1a was detected in 41.2% of the HCV-HIV-coinfected patients and was associated with intravenous drug use (IVDU). The HCV-3 strains belonged to subtype 3a and were linked to IVDU. Phylogenetic analyses were focused on HCV-2 and HCV-4, which are common in Africa. Two opposite patterns were evidenced. NS5B sequences from 19 HCV-2 isolates were affiliated with many different subtypes described either in Europe or in West Africa, suggesting an ancient radiation. In contrast, seven of the nine HCV-4 NS5B sequences ranged within HCV-4a and HCV-4d clusters spreading in continental France by the IVDU route. Epidemiological data demonstrate the recent introduction of HCV-4a and -4d subtypes into the Caribbean.  相似文献   
62.
The effectiveness of galactomannan detection with the Platelia test was evaluated in a prospective study of 3,327 sera from 807 patients. The specificity was 99.6% (748 of 751 cases). For the groups of patients with proven and probable invasive aspergillosis, the sensitivity was 50.0% (17 of 34 cases). The disappointing sensitivity associated with the presence of rare false-positive cases underlines the limits of this test.  相似文献   
63.
Critical shortages of trained histopathologists limit the capacity of cancer and other clinical services. A survey of histopathology training in 18 European countries conducted by the European Union of Medical Specialists Section of Pathology/European Board of Pathology revealed a considerable shortage of both trained and trainee histopathologists in several of the responding countries. Demographic data indicate a high preponderance of trained histopathologists over 55 years of age and a notable proportion of part-time personnel. Although the training capacity in some countries has been increased, the immediate future of histopathology and the clinical services dependent on the specialty is worrisome. The histopathology workload is growing, and, in some countries, recruitment of trainees is insufficient for future needs. To avert the serious consequences for dependent clinical specialties and their patients, there should be a concerted European action to promote and expand histopathology training.  相似文献   
64.
65.
OBJECTIVE: The major aim was to explore the extent to which the Miller Behavioral Style Scale (MBSS) can be used to differentiate cancer patients who are likely to benefit from rehabilitation efforts with a strong information component from those who are not. METHODS: Newly diagnosed patients with breast, gastrointestinal, or prostate cancer (N = 442) were included in a randomized, prospective study of the effects (on anxiety, depression, intrusion, avoidance) of rehabilitation approximately 4 months after diagnosis as compared with control patients. Patients were classified as "monitors" or "blunters" on the basis of the MBSS (368 patients, 83%, completed the MBSS). RESULTS: The expected interaction at postintervention between coping style and experimental condition (ie, rehabilitation or control) was found only for avoidance among breast and prostate cancer patients. Assignment to the rehabilitation or control condition was of no importance for outcome among blunters. Among monitors, the response pattern differed between breast and prostate cancer patients. Prostate cancer monitors seemed to benefit from rehabilitation on all outcome measures, whereas intrusion and avoidance were reduced among breast cancer patients in the control condition. This interaction of diagnosis with condition (rehabilitation or control) among monitors is suggested to be due to demands for diagnosis-specific information during diagnostic work, in the period just after diagnosis, and before treatment decision. CONCLUSIONS: Only the monitor concept seems useful for predicting response to cancer rehabilitation with a strong information component. However, whether rehabilitation is of benefit depends also on other factors.  相似文献   
66.
In 331 patients with the diagnosis of multiple myeloma in 4 cases proliferation of plasma cells was associated with synthesis of a monoclonal IgM. In 3 of these cases coexistence was noted of features typical of multiple myeloma and Waldenstr?m's macroglobulinaemia. In the clinical picture in two of these cases sings of blood hyperviscosity prevailed. These patients showed impairment of plasma clotting factors. The count of T and B cells in blood and the adherence and phagocytic activity of monocytes were not abnormal. The ultrastructural pattern of plasma cells in bone marrow was similar to that observed in classical cases of IgG or IgA multiple myeloma. In one case of lymphoplasmocytic proliferation with leucocytosis over 100 x 10(9)/l immunoelectroscopic examination of bone marrow cells demonstrated a formidable accumulation of the heavy chain of mu immunoglobulin in the cytoplasm of lymphoplasmacytes. In the serum and urine no monoclonal protein was found. In this case compression of vertebral bodies Th7 and L2 occurred.  相似文献   
67.
In addition to the two large clostridial cytotoxins (TcdA and TcdB), some strains of Clostridium difficile also produce an actin-specific ADP-ribosyltransferase, called binary toxin CDT. We used a PCR method and Southern blotting for the detection of genes encoding the enzymatic (CDTa) and binding (CDTb) components of the binary toxin in 369 strains isolated from patients with suspected C. difficile-associated diarrhea or colitis. Twenty-two strains (a prevalence of 6%) harbored both genes. When binary toxin production was assessed by Western blotting, 19 of the 22 strains reacted with antisera against the iota toxin of C. perfringens (anti-Ia and anti-Ib). Additionally, binary toxin activity, detected by the ADP-ribosyltransferase assay, was present in only 17 of the 22 strains. Subsequently, all 22 binary toxin-positive strains were tested for the production of toxins TcdA and TcdB, toxinotyped, and characterized by serogrouping, PCR ribotyping, arbitrarily primed PCR, and pulsed-field gel electrophoresis. All binary toxin-positive strains also produced TcdB and/or TcdA. However, they had significant changes in the tcdA and tcdB genes and belonged to variant toxinotypes III, IV, V, VII, IX, and XIII. We could differentiate 16 profiles by using typing methods, indicating that most of the binary toxin-positive strains were unrelated.  相似文献   
68.
Summary For the investigation of epitope composition of different adenovirus hexon types sixty-one mouse ascitic fluids containing monoclonal antibodies (MAbs) developed in three different panels were used. The distinction and marking of the different epitopes recognized by the MAbs were carried out by the determination of the composite cross-reactivity pattern, the titer and the correlation coefficient of all the 61 MAbs with 21 different hexon types representing all the six human subgenera, as well as different bovine and simian adenoviruses. The distinct epitopes were marked by two numbers refering the homologous hexon type to which the MAbs were directed and the serial number of the epitope specified by the different members of the given panel of the MAbs. The three panels of MAbs recognized 22 epitopes on the 21 hexon types among them a genus and three type specific ones and 18 different bi- and multilateral intertype (IT) specific epitopes that grouped adenoviruses within the genus, independently from the subgenus they belong to. Considering that the type specific epitope could be present only on the homologous hexon type, the largest number of the different epitopes distinguishable by the MAbs used could be 20 on the homologous hexon and 19 on the heterologous ones. It was found that the total number of IT specific epitopes on the hexons varied between 2 and 18. The distribution of the distinct specific epitopes on the different hexon types was different, as expected. The antigenic structure of the individual hexon types were characterized by the determination of their IT specific epitope spectrum. By pairwise analysis ten human hexon types formed three epitope clusters (types 4 and 19; types 8, 9, 9/13 and 10; as well as all types of subgenus C) showing identical epitope spectra. No clustering was found with human type 7, 12, 13, 18, 26, 27, 35 and 41, as well as with bovine and simian adenovirus hexons studied. However, they displayed a closer or looser antigenic relationship among each other and to members of the epitope clusters. The degree of antigenic relationship could be expressed by the similarity/dissimilarity percentage calculated from the number of the identical and different epitopes present on any two given hexon types.  相似文献   
69.
The thermal responses of neonates during a cool acclimation period were studied with regard to sleep stages. Sleep stages, body temperatures and metabolic rate (VO2) were studied for seven neonates nursed in incubators and exposed to a cool temperature (thermoneutrality minus 2 degrees C) for 75 h. Each recording session lasted 3 h in the morning: firstly under thermoneutral baseline conditions, then during the first and last 3-h periods of the cool acclimation and finally during the last 3 h of a 24-h recovery period. Sleep structure was modified during the initial hours of cool exposure: the percentage of active sleep increased (AS: +13%, P = 0.028) at the expense of quiet sleep (QS: -11%, P = 0.043). This alteration in sleep structure persisted at the end of the acclimation period. Metabolic heat production only increased in the later period of cool acclimation. Throughout the cool exposure, VO2 increased more (P = 0.040) in QS (+33%) than in AS (+20%) so that by the end of the cool period, VO2 levels were similar in both sleep stages. During cool acclimation, the maintenance of homeothermy is related not only to a change in sleep organization but also to modifications in the thermoregulatory processes in both sleep stages. Considering the importance of AS/QS patterns in the neurobehavioral development of neonates, the present results could have clinical implications for the thermal management of neonates.  相似文献   
70.
Functional proteomics mapping of a human signaling pathway   总被引:5,自引:0,他引:5       下载免费PDF全文
Access to the human genome facilitates extensive functional proteomics studies. Here, we present an integrated approach combining large-scale protein interaction mapping, exploration of the interaction network, and cellular functional assays performed on newly identified proteins involved in a human signaling pathway. As a proof of principle, we studied the Smad signaling system, which is regulated by members of the transforming growth factor beta (TGFbeta) superfamily. We used two-hybrid screening to map Smad signaling protein-protein interactions and to establish a network of 755 interactions, involving 591 proteins, 179 of which were poorly or not annotated. The exploration of such complex interaction databases is improved by the use of PIMRider, a dedicated navigation tool accessible through the Web. The biological meaning of this network is illustrated by the presence of 18 known Smad-associated proteins. Functional assays performed in mammalian cells including siRNA knock-down experiments identified eight novel proteins involved in Smad signaling, thus validating this integrated functional proteomics approach.  相似文献   
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