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Cognitive impairment in multiple sclerosis (MS) is common, debilitating and burdensome. Key evidence from trials was reviewed to enable recommendations to be made to guide clinical practice and research. Behavioural and pharmacological interventions on cognition reported in published studies were reviewed. Most studies evaluating behavioural treatment for impairment in learning and memory, deficits of attention and executive function have demonstrated some improvement. Controlled studies in relapsing remitting MS indicate interferon (IFN) β-1b and IFN β-1a were associated with modest cognitive improvement. The effects of symptomatic therapies such as modafinil and donepezil are inconsistent. Most studies yielding positive findings have significant methodological difficulties limiting the confidence in making any broad treatment recommendations. There are no published reports of glatiramer acetate, natalizumab and fingolimod being effective in improving cognition in controlled trials. The effects of disease modifying therapies in other forms of MS and clinically isolated syndrome have not yielded positive results. Data linking behavioural therapy, symptomatic treatment or disease modifying treatment, to either reducing cognitive decline or improving impaired cognition are limited and inconsistent. The treatment and prevention of cognitive impairment needs to remain a key research focus, identifying new interventions and improving clinical trial methodology.  相似文献   
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Worldwide approximately 68 million people are infected with lymphatic filariasis (Lf), provoked by Wuchereria bancrofti, Brugia malayi and Brugia timori. This disease can lead to massive swelling of the limbs (elephantiasis) and disfigurement of the male genitalia (hydrocele). Filarial induced immune regulation is characterised by dominant type 2 helper T cell and regulatory immune responses. In vitro studies have provided evidence that signalling via Toll-like receptor-mediated pathways is triggered by filarial associated factors. Nevertheless, until now, less is known about the role of the adapter molecule TRIF during in vivo infections. Here, we used the rodent-specific nematode Litomosoides sigmodontis to investigate the role of TLR signalling and the corresponding downstream adapter and regulatory molecules TRIF, MyD88, IRF1 and IRF3 during an ongoing infection in semi-susceptible C57BL/6 mice. Interestingly, lack of the central adapter molecule TRIF led to higher worm burden and reduced overall absolute cell numbers in the thoracic cavity (the site of infection) 30 days post-infection. In addition, frequencies of macrophages and lymphocytes in the TC were increased in infected TRIF−/− C57BL/6 mice, whereas frequencies of eosinophils, CD4+ and CD8+ T cells were reduced. Nevertheless, cytokine levels and regulatory T cell populations remained comparable between TRIF-deficient and wildtype C57BL/6 mice upon 30 days of L. sigmodontis infection. In summary, this study revealed a crucial role of the adapter molecule TRIF on worm recovery and immune cell recruitment into the site of infection 30 days upon L. sigmodontis infection in C57BL/6 mice.

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The 13th edition of the standards of the American Association of Blood Banks specified storage at 1 to 6 degrees C for cryoprecipitated anti-hemophilic factor (Cryo) administered up to 6 hours after thawing if the Cryo is used for factor VIII (FVIII) content (Standard J4.210). Previous editions specified room-temperature (RT) storage for up to 6 hours. Currently, the temperature specification has been deleted. There are few data addressing the optimal storage temperature and maximum storage time for FVIII and fibrinogen in thawed Cryo. Thirty bags of Cryo were assayed for FVIII and fibrinogen. Each bag was divided into two aliquots; one was stored at RT and the other at 1 to 6 degrees C. Assays were performed immediately after thawing (Base) and 6 and 24 hours after thawing, respectively. All samples were filtered through 200-mu blood component infusion sets before assay. Three hundred analyses were performed, 150 each for FVIII and fibrinogen by conventional clotting technique. Data were analyzed by using a paired t test. Cryo stored at 1 to 6 degrees C for 6 and 24 hours showed an FVIII loss of 35 percent (p less than 0.0001) and 63 percent (p less than 0.0001), respectively. Cryo stored at RT for 6 and 24 hours had an FVIII loss of 8 percent (p greater than 0.05) and 20 percent (p less than 0.0001). Cryo stored at 1 to 6 degrees C for 6 and 24 hours had a fibrinogen loss of 20 percent (p less than 0.0001) and 43 percent (p less than 0.0001). Cryo stored at RT for 6 hours had no fibrinogen loss and a 2 percent loss at 24 hours (p greater than 0.05). These preliminary data show a significant loss of FVIII and fibrinogen activity in Cryo stored at 1 to 6 degrees C and filtered before assay. The FVIII and fibrinogen activity at RT is clearly maintained up to 6 hours after thawing.  相似文献   
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Chlamydia trachomatis infections are among the most common sexually transmitted diseases and of great epidemiological importance world-wide. Identification of this pathogen can be difficult, and it is highly desirable to have a rapid and accurate nucleic acid based detection method. Several commercial PCR test systems are available (e.g. CobasAmplicor, Roche, Mannheim, Germany) but they require post-amplification detection by hybridization resulting in extended work-up time and possible cross-contamination. The objective of our study was to develop a routine diagnostic method for the sensitive, specific and rapid detection of C. trachomatis. The obvious choice is real-time PCR without any post-amplification procedures. The dye SYBR Green I (intercalating in dsDNA) provides a simple and fast real-time PCR in the LightCycler. Specific primer design combined with melting curve analysis allows a reliable and sensitive identification of C. trachomatis. In addition, a new commercial real-time PCR system (RealArt C. trachomatis LC PCR Reagents, artus, Hamburg, Germany) was evaluated, that combines sequence-specific primers and fluorescence-labelled (FRET) 5'-nuclease probes. An internal control integrated in this system detects false negative results and erroneous PCR conditions. All results were compared with the corresponding data from an analysis using the CobasAmplicor system (Roche). (Clin  相似文献   
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A near-fatal reaction during granulocyte transfusion of a neonate   总被引:1,自引:0,他引:1  
Although reactions to granulocyte transfusions in neonates are rarely reported, we observed a near-fatal pulmonary reaction, presumably due to white cell antibodies, in a neonate with Rh hemolytic disease. The hemolytic disease was being treated with exchange transfusions, and at 2 days after the infant's birth, bacterial sepsis was suspected and granulocyte transfusions were begun. The first granulocyte transfusion (Day 3) was uneventful. Five minutes after the beginning of the second granulocyte transfusion (Day 4), severe respiratory distress, hypotension, bradycardia, cyanosis, and acidosis suddenly occurred. The infant's serum obtained after the reaction contained granulocytotoxic and B-lymphocytotoxic antibodies that reacted with leukocytes from the second granulocyte donor. Antibodies could not be detected either in the initial infant serum or in maternal serum. However, an antileukocyte antibody was present in the serum of a parous woman donor. We used plasma from this woman to prepare reconstituted whole blood for the exchange transfusion that we performed immediately preceding the second granulocyte transfusion. Despite the sequence of events, an irrefutable cause-and-effect mechanism could not be established because the properties of the donor and neonatal antibodies were similar, but not identical. However, this catastrophic event emphasizes both the potential for adverse effects of granulocyte transfusions in neonates and the need for caution when transfusing blood from parous women.  相似文献   
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Nonalcoholic fatty liver disease (NAFLD), frequently already present in young subjects, has been linked to reduced growth hormone levels and signaling. Similar hormonal changes occur during metabolic acidosis (MA), which may thus contribute to an increased NAFLD risk. Because subclinical MA can be diet induced, we aimed to examine whether a higher diet-dependent acid load during adolescence is prospectively associated with several currently used NAFLD surrogates in young adulthood. Dietary acidity during adolescence (boys:10-15 y, girls: 9-14 y) was calculated as potential renal acid load (PRAL) from at least three 3-d weighed dietary records according to a published algorithm considering dietary protein and minerals in 145 healthy participants. Routine measurements derived from blood analysis and anthropometric data in participants' young adulthood (18-25 y) were used to determine the NAFLD surrogates alanine-aminotransferase (ALT), hepatic steatosis index (HSI), and fatty liver index (FLI). Sex-stratified linear regression models, adjusted for dietary fiber, saturated fat, protein, and adolescent BMI SD scores, were run with PRAL as the independent variable. Dietary PRAL during puberty was positively associated with ALT (P = 0.02), HSI (P = 0.002), and FLI (P = 0.005) in adult females but not males. Females with an adolescent dietary acid load in the highest tertile had 3.5, 4.4, and 4.5 higher values of ALT, HSI, and FLI as adults, respectively, compared to females with the lowest PRAL. The present findings suggest that higher dietary acidity in adolescence may be prospectively associated with hepatic lipid accumulation in females. Whether this relationship is due to the higher proton load or rather represents an unhealthy dietary pattern requires further investigation.  相似文献   
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BACKGROUND: An increasing number of apheresis machines are becoming available for peripheral blood progenitor cell (PBPC) collection in children. STUDY DESIGN AND METHODS: At the Children's Hospital of Florence (Italy), three apheresis machines were evaluated: MCS 3P (Haemonetics) (10 procedures in 4 patients, aged 10–12 years, weight 23.5-64 kg), Spectra, (COBE) (8 procedures in 3 patients, aged 4–17 years, weight 19–59 kg), and AS104 (Fresenius) (24 procedures in 9 patients, aged 2–16 years, weight 13.6-60 kg). For PBPC quantitative analysis, CD34 cytofluorimetry was employed. Relevant variables analyzed included efficiency of CD34+ cell extraction and enrichment, mononuclear cell purity and red cell contamination of the apheresis components, and platelet count decreases after leukapheresis. RESULTS: No significant differences in CD34+ cell-extraction abilities were found. However, the AS104 provided consistently purer leukapheresis components in terms of mononuclear cell and CD34+ cell enrichment (441 +/− 59%, vs. 240 +/− 35% and 290 +/− 42% for MCS 3P and Spectra, respectively). Postapheresis platelet counts dropped the least with the AS104. The smallest patient who underwent apheresis with MCS 3P (the only machine working on discontinuous flow and hence with greater volume shifts) weighed 23.5 kg and tolerated the procedure well, with no signs of hemodynamic instability. No significant complications were observed. CONCLUSION: All machines seem to have comparable PBPC extraction efficiency, but the AS104 seems to give the component with the greatest PBPC enrichment. This feature might be relevant for further ex vivo cell processing (CD34+ cell selection, expansion, and so on).  相似文献   
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