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61.
62.
H-ras p21 protein expression was investigated in bladder and colonic tumor tissues using an H-ras specific antibody in Western blot analysis. The specificity of this antibody to H-ras proteins was established using NIH/3T3 transfectants expressing oncogenic counterparts of the different ras gene family members. Use of this antibody to detect altered H-ras proteins was demonstrated using a panel of transfectants bearing different mutated H-ras genes and established cell lines previously characterized in transfection assays. Extension of this technique to direct analysis of human tumor material confirmed previous observations of H-ras activation within a group of bladder tumors and identified three more urothelial tumors expressing altered H-ras proteins. The altered migrational properties of these three were suggestive of point mutational events in 12 (1 case) and 61 (2 cases) codon hot spots. This study extends previous observations on the preferential activation of H-ras in urinary tract tumors and provides a rapid technique for evaluating the status of H-ras proteins in human tumor tissue.  相似文献   
63.
The new 2017 diagnostic criteria for hypermobile Ehlers–Danlos Syndrome (hEDS) provide a framework for diagnosing hEDS but are more stringent than the previous Villefranche criteria. Our clinical experience at the GoodHope EDS clinic was that the 2017 criteria left many highly symptomatic patients without a diagnosis of hEDS. We conducted a retrospective cohort study to confirm our clinic experience and assess the accuracy of the 2017 diagnostic criteria for hEDS in patients who had a previous hEDS diagnosis based on the Villefranche criteria. Our study found that 15% (n = 20 of 131) of patients with a prior diagnosis of hEDS met the 2017 diagnostic criteria, and many of the traits used to distinguish hEDS were not significantly more frequent in patients who met 2017 criteria versus those who did not. In both groups objective systemic manifestations were found less frequently than subjective systemic manifestations. Beighton score (BS) as assessed by primary care practitioner was found to be higher than assessment by EDS practitioner in 81% (n = 74 of 91) of cases. Generalized joint hypermobility was confirmed in only 46% (n = 51 of 111) of patients who had a previous diagnosis of hEDS. Higher BS did not correlate with increased number of systemic manifestations in our cohort. Common comorbidities of hEDS were found with similar frequency in those who met 2017 criteria and those who did not. Based on our cohort, the 2017 hEDS diagnostic criteria require refinement to improve its diagnostic accuracy.  相似文献   
64.
65.
The detection of anti-HBs antibody has been carried out using a new technique where a system for the detection of HBs antigen in the solid phase is adopted to demonstrate the presence of anti HBs antibody by inhibition of the immunoenzymatic reaction. The sensitivity of the method has been compared: with that of passive haemagglutination and with that of radioimmunoassay in liquid phase, for human serum obtained from 10 chronic antibody carriers and also serum from 1 rabbit, with that of solid phase radioimmunoassay for 91 positives serums. The method appears: in the range of sensitivity of passive haemagglutination and radioimmunoassay in the liquid phase, less sensitive than that of solid phase radioimmunoassay, far superior to that of electrosyneresis.  相似文献   
66.
Rabbits made acute phase by sub-cutaneous trauma with 2% croton oil (in mineral oil) were tested by intradermal (ID) injection with platelet-granule extracts containing platelet-derived permeability factor (PDPF). Compared with controls, skin reactivity to PDPF was enhanced in acute phase animals 3–7 days post-trauma, a period of acute inflammation as reflected by the occurrence in the circulation of C-reactive protein; maximal skin responses were observed 3–4 days post-trauma. Individual skin sites reached maximum intensity 15 min–1 hour post-ID injection of PDPF and were sensitive to chlorpheniramine maleate, suggesting a major role for histamine. Intradermal injection of histamine revealed that acute phase animals yielded an initially more intense skin reaction, and were markedly less capable of recovering from the effects of histamine. These data suggest that in the acute phase, there exists a heightened and prolonged sensitivity to the action of histamine which can be exploited by pro-inflammatory agents such as PDPF.This work was supported, in part, by grants from the NIH (HL-23457) and the Institut Pasteur de Lyon. B.A.F. is the recipient of NIH Career Development Award (HL-00614). The majority of these studies were performed on sabbatical at the Institut Pasteur de Lyon (B.A.F.).  相似文献   
67.
This report describes an adult male with a partial trisomy 6p(p211-pter) and a partial monosomy 9p(9p24-pter) resulting from a de novo unbalanced translocation. This patient does not show the classical featured of the 9p partial monosomy syndrome, thus disputing the claim of Hoo et al. (1982) that 9p24 is the critical segment for the monosomy syndrome. Partial trisomy for 6p has only been previously reported in children. In addition to the chromosomal anomalies, the patient has autosomal recessive spinal muscular atrophy with a different age of onset than two affected sibs. Finally, he shows unusual audiologic and ophthalmologic signs nor previously reported as part of the 9p monosomy or 6p trisomy syndromes.  相似文献   
68.
Urethane anesthetized (< 1 .3 g/kg), Sprague-Dawley (SD) rats spontaneously cycled between a cortically desynchronized state (State I) and a cortically synchronized state (State III), which were very similar to awake and slow wave sleep (SWS) states in unanesthetized animals, based on EEG criteria. These low levels of urethane anaesthesia did not cause significant respiratory depression or reductions in sensitivity to hypoxia (10% O2 in nitrogen) or hypercapnia (5% CO2 in air) in rats in either State I or State III. Thus, breathing frequency (fR), tidal volume (VT) and total ventilation (VTOT) all increased on cortical activation in urethane-anaesthetized rats whether breathing air, the hypoxic or the hypercapnic gas mixture, in a manner that was very similar to that observed in unanaesthetized animals. The relative sensitivity to hypoxia was greater in State III than State I, the relative sensitivity to CO2, overall, was equal in both states, State III occurred less often during hypoxia and hypercapnia, and hypoxic, urethane-anaesthetized rats sighed frequently, particularly in State I. This is also similar to the situation seen in unanesthetized rats. Given the similarities seen between urethane anesthetized rats in the present study and literature values for unanesthetized rats, the data suggest that urethane-anaesthetized rats provide a good model system for studying respiratory patterns and chemoreflexes as a function of cortical activation state.  相似文献   
69.

Background  

In multiple sclerosis, inflammatory cells are found in both active and chronic lesions, and it is increasingly clear that cytokines are involved directly and indirectly in both formation and inhibition of lesions. We propose that cytokine mixtures typical of Th1 or Th2 lymphocytes, or monocyte/macrophages each induce unique molecular changes in glial cells.  相似文献   
70.
Nonspecific factors such as placebo or expectancy effects may materially influence therapeutic outcome in EMG relaxation training. Yet, controlling for the expectations of experimenters has received little attention even though Rosenthal's Experimenter Expectancy Effect is well-documented. This study examined the effects of experimenter expectancy on frontal EMG conditioning. During training, experimenters were given either no expectancy or led to believe that EMG conditioning would he either difficult (low expectancy) or easy (high expectancy) to achieve. Then, the three groups of experimenters collected data from subjects undergoing 20 min of either contingent or noncontingent reinforcement for frontal EMG decreases. Postexperimental credibility checks indicated that experimenters were unaware they were being studied but could identify their expectancy condition when informed of the three conditions. Differential EMG behavior was observed between groups conditioned by experimenters with no expectancies, with contingent subjects achieving significantly lower EMG levels than noncontingent subjects. Differences were not exhibited, however, between contingent and noncontingent subjects trained by experimenters with either low or high expectancies. These findings suggest that experimenters with prior expectations may covertly communicate to subjects response sets that interfere with acquisition of differential EMG behavior.  相似文献   
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