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21.
The acidic ribosomal proteins of the protozoan parasite Leishmania infantum have been described as prominent antigens during both human and canine visceral leishmaniasis. In this study we present data showing that the intraperitoneal administration in BALB/c mice of the Leishmania LiP2a protein, in the absence of any added adjuvants, elicited a strong humoral response as an indication that the protein is a potent immunogen. Despite the evolutionary conservation of the acidic ribosomal proteins, the antibody response was found to be specific for the Leishmania protein. Another remarkable finding was the observation that the LiP2a protein stimulates the in vitro proliferation of splenocytes from either LiP2a-immunized or naive BALB/c mice. Since similar proliferative indices were observed in T cell-enriched cultures, it is likely that the LiP2a stimulating activity is due mainly to T lymphocyte expansion. Also, the stimulatory effect was demonstrated to be antigen-specific, since the proliferation was abrogated by the presence of anti-LiP2a antibodies. Interestingly, the LiP2a protein stimulated the production of substantial amounts of IFN-gamma in cultured splenocytes from LiP2a-immunized mice. Our data indicate therefore that the immunostimulatory properties shown by this antigen should be taken into account when developing therapeutic and prophylactic vaccines against leishmaniasis.  相似文献   
22.
To evaluate enzyme immunoassay (EIA) as an alternative to indirect immunofluorescence assay (IFA) to screen for Q fever in humans, 157 serum samples from patients suspected of having the disease were tested for immunoglobulin G antibodies toCoxiella burnetii. The agreement between the tests and the sensitivity of EIA were excellent (96.8% and 98.4%, respectively) when an IFAtiter of > 1/160 was considered positive. All serum samples with a titer of > 1/320 in the IFA were also positive by the EIA. The EIA seems to be an acceptable alternative to IFA for screening for Q fever.  相似文献   
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24.
The ERAS guidelines are intended to identify, disseminate and promote the implementation of the best, scientific evidence-based actions to decrease variability in clinical practice. The implementation of these practices in the global clinical process will promote better outcomes and the shortening of hospital and critical care unit stays, thereby resulting in a reduction in costs and in greater efficiency. After completing a systematic review at each of the points of the perioperative process in cardiac surgery, recommendations have been developed based on the best scientific evidence currently available with the consensus of the scientific societies involved.  相似文献   
25.
In order to find out if the decreased accumulation of cerebroside sulfates observed in 21-d-old undernourished rats was in part the result of an increased rate of catabolism of these galactolipids, the in vivo degradation of brain cerebroside sulfates was studied in 18-d-old normal and undernourished rats. Two hours after the intracranial injection of the precursor (0 time), the animals were injected intraperitoneally with unlabeled sodium sulfate. Labeled cerebroside sulfates were measured in the brain up to 48 h after the chase. In normal animals, the radioactivity decreased at 24 h and 48 h to 55% and 41%, respectively, of the value obtained at 0 time. In undernourished animals, degradation was negligible, since the radioactivity attained at 0 time remained almost constant up to 48 h. The lack of in vivo degradation of cerebroside sulfates observed in the starved rats cannot be explained by a deficiency of Arylsulfatase A, since the pattern of activity of the enzyme was similar in both groups of animals.  相似文献   
26.
OBJECTIVE: To determine the prevalence of antibodies to HIV-1 and risk factors for HIV-1 infection among injection drug users. DESIGN: Questionnaire survey. A venous blood sample was taken for HIV-1 antibody testing. SETTING: Montreal and Toronto. PARTICIPANTS: A total of 810 subjects who had used injection drugs in the previous 6 months recruited mainly from treatment centres and from the street in Montreal (425 subjects) and from treatment centres in Toronto (385 subjects) between September 1988 and September 1990. The overall participation rate was 82%. OUTCOME MEASURES: HIV-1 seropositivity, sociodemographic and behavioural risk factors for HIV-1 infection. RESULTS: The overall seroprevalence rate of HIV-1 infection was 4.8% (95% confidence limits [CL] 3.5 and 6.5). In Montreal the rate was 8.2% (95% CL 6.0 and 11.2), and in Toronto 1.0% (95% CL 0.4 and 2.6) (p < 0.001). Seropositive subjects were significantly older (p = 0.041) and were more likely to have a history of imprisonment (p = 0.006) than seronegative subjects. In univariate analysis seropositivity was associated with the following behaviours: more frequent cocaine use (p < 0.001), injecting drugs in "shooting galleries" (p = 0.002), sharing equipment with a person known to be HIV-1 seropositive (p = 0.006), "booting" fresh blood (p = 0.004), homosexual or bisexual orientation (p = 0.006), engaging in prostitution (p < 0.001) and, for men, number of male sexual partners in the previous 6 months (p = 0.007). In multivariate analysis the determinants of HIV-1 seropositivity were Montreal as the city of recruitment (odds ratio [OR] 6.7, 95% CL 2.32 and 19.42), engaging in prostitution (OR 2.13, 95% CL 1.01 and 4.75), a history of imprisonment (OR 3.51, 95% CL 1.33 and 9.29) and sharing equipment with a person known to be HIV-1 seropositive (OR 4.43, 95% CL 1.43 and 13.74). CONCLUSIONS: Our findings show that HIV-1 is circulating among injection drug users in Montreal and Toronto and that both drug use and sexual behaviours are implicated in the transmission of infection in the populations studied. Adapted preventive programs should be developed to prevent further spread of HIV-1 infection in this population.  相似文献   
27.
The objective of this study was to assess the effectiveness of a hygiene program in reducing the incidence of respiratory and diarrheal diseases in toddlers attending day care centers. A randomized field trial was conducted in 52 day care centers in Quebec, Canada, between September 1, 1996 and November 30, 1997. Absences for any reasons and the daily occurrence of colds and/or diarrhea in toddlers were recorded on calendars by the educators. The number of fecal coliforms on children's hands and on educators' hands was measured during three unannounced visits. Overall, 1,729 children were followed in 47 day care centers for a total of 153,643 child-days. The incidence rate of diarrhea was considerably reduced by the effect of monitoring (IRR = 0.73, 95% CI = 0.54,0.97), and the intervention reduced the incidence rate of upper respiratory tract infections (IRR = 0.80, 95% CI = 0.68,0.93). Monitoring alone also had an important effect in reducing the level of bacterial contamination on children's and educators' hands. The results indicate that both an intervention program and monitoring alone play a role in reducing infections in children attending day care centers.  相似文献   
28.
The suramin analogue 8,8'-(carbonylbis(imino-3,1-phenylene carbonylimino)bis(1,3,5-naphthalenetrisulfonic acid) (NF023) antagonizes in a competitive fashion P2X receptor-mediated responses in certain vascular and visceral smooth muscles. In the present study, the effect of NF023 on voltage-clamped Xenopus oocytes heterologously expressing homomultimeric P2X1-P2X4 as well as heteromultimeric P2X2/P2X3 receptors has been characterized. P2X1 receptors were most sensitive to inhibition by NF023 with IC50 values of 0.24 and 0.21 microM for the rat and human homologue, respectively. P2X3 receptors have an intermediate sensitivity with IC50 values of 8.5 and 28.9 microM for rat and human subtypes, respectively and P2X2 was the least sensitive subtype (IC50 > 50 microM). P2X4 receptors were insensitive to NF023 at concentrations up to 100 microM. Coexpression of rat P2X3 with rat P2X2 resulted in receptors whose sensitivity to NF023 was identical to that obtained for homomultimeric rat P2X3 receptors (alphabeta meATP as agonist; IC50 = 1.4 and 1.6 microM, respectively). NF023 inhibited P2X1 receptors in a voltage-insensitive manner. In addition, NF023 (5 and 30 microM) caused a shift of the concentration-response curve to the right without affecting the maximal response to ATP (K(B) = 1.1 +/- 0.2 microM). Our results indicate that NF023 is a subtype-selective and surmountable antagonist at P2X1 receptors heterologously expressed in Xenopus oocytes.  相似文献   
29.
Some newborns with congenital diaphragmatic hernia (CDH) and severe pulmonary hypertension cannot be saved by conventional treatment and may obtain some benefit from extracorporeal membrane oxygenation (ECMO) as a bridging measure until adequate hematosis is possible. Early prediction of the insufficiency of optimal assistance is still unclear; we reviewed our recent experience with CDH patients in an attempt to evaluate the real need for ECMO in our institution. Between 1987 and 1994, 47 newborns with CDH manifested in the first 24 h were treated with maximal ventilatory assistance (including high-frequency ventilation in 12 cases) and vasoactive drugs prior to surgical repair. In order to summarize the ventilatory and blood-gas parameters, we determined oxygenation index (OI) and ventilatory index (VI) and compared the results in survivors and nonsurvivors. Overall survival was 60% (2 cases of Fryns' syndrome were excluded from analysis). OI was 10.3±5.7 (mean ± SD) for survivors and 46.2 ± 37.8 for nonsurvivors (P < 0.01). VI was 460.9±303 and 1,532±500.6, respectively (P <0.01). Bayesian analysis and receiver operating characteristic curves enabled us to select a threshold value of OI of 20 as the best means of predicting survival in our current conditions (sensitivity: 0.7, specificity: 0.83). The generally accepted figure of 40 had a sensitivity of 1 but a specificity of only 0.44. For VI, the best threshold value was 1,100 (sensitivity: 0.93, specificity: 0.94), whereas the generally used figure of 1,000 had 0.89 and 1, respectively. According to our results, with our current management conditions, approximately 50% of our CDH patients might have obtained some benefit from ECMO.  相似文献   
30.
A study of breast cancer mortality and cancer morbidity has been carried out in Spain recently for the period 1977–1988, covering the population of the 17 Autonomous Communities and 50 provinces of the country. Data was obtained from INE, Instituto Nacional de Estadistica (National Institute of Statistics), with age standardization using the indirect method. The different Autonomous Communities and provinces were compared in order to establish possible significant differences. The crude mean mortality rate was 21 cases per 100,000 inhabitants/year; Las Palmas, Gerona, Barcelona, the Balearic Islands, Navarra and Zaragoza have the highest mortality rates, with a proportional increment of 54% in that period. The crude national mean morbidity rate for the considered period was 64.0 cases per 100,000 inhabitants, and the proportional increment 180%. According to provincial figures, Alava had the highest fitted mean morbidity rate, 135 cases per 100,000 inhabitants, whilst the highest fitted mean rate was Las Palmas (28 cases/100,000 inhabitants), and the highest proportional increment was the rate for the province of Huesca (169%). When using the ANOVA test on the mean rate of the period, for mortality as well as morbidity, we observed significant differences among provinces and among Autonomous Communities (p 0.05).  相似文献   
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