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91.
Vasculitis represents an uncommon but important group of disease entities that may affect older patients. The most common systemic vasculitic disease in humans is giant cell arteritis, a disease process seen almost exclusively in patients over the age of 50. Vasculitic disease in geriatric patients presents unique challenges with regard to diagnosis and treatment. A thorough understanding of the vasculitic disease entities that may affect older patients as well as their diagnosis and management is essential in minimizing disease and treatment related morbidity and mortality.  相似文献   
92.
Commensal neisseriae share with Neisseria meningitidis (meningococcus) a tendency towards overproduction of the bacterial outer envelope, leading to the formation and release during growth of outer membrane vesicles (OMVs). OMVs from both meningococci and commensal neisseriae have shown promise as vaccines to protect against meningococcal disease. We report here the successful expression at high levels of heterologous proteins in commensal neisseriae and the display, in its native conformation, of one meningococcal outer membrane protein vaccine candidate, NspA, in OMVs prepared from such a recombinant Neisseria flavescens strain. These NspA-containing OMVs conferred protection against otherwise lethal intraperitoneal challenge of mice with N. meningitidis serogroup B, and sera raised against them mediated opsonophagocytosis of meningococcal strains expressing this antigen. This development promises to facilitate the design of novel vaccines containing membrane protein antigens that are otherwise difficult to present in native conformation that provide cross-protective efficacy in the prevention of meningococcal disease.  相似文献   
93.
94.
The purpose of this study was to determine the reliability of the 1- and 3RM tests for the modified unilateral squat. Thirty untrained (22 women, 8 men) and 22 trained (12 women, 10 men) subjects participated in the study. The trained group had a minimum of 1 year lower-body training experience but had not participated in unilateral training prior to the study. After practicing proper technique with light loads, the subjects used the barbell squat to complete a 1- and 3RM pretest and posttest. In each group half of the subjects completed the 1RM tests prior to the 3RM tests while half of the subjects completed the 3RM tests first. A rest period of 48 hours was allowed between each test. Twenty subjects, randomly selected from the two groups, completed a third session of the 1RM test 3 days after the 1RM posttest. Intraclass correlation coefficients were recorded. Differences between pre- and posttest measures were determined by the paired-sample t-test. The 1- and 3RM tests were found to be significantly reliable for trained men, r = 0.98 and r = 0.97, untrained men, r = 0.99 and r = 0.97, trained women r = 0.99 and r = 0.94, and untrained women, r = 0.97 and r = 0.87, respectively. Posttest scores for the 1- and 3RM tests significantly improved above baseline levels in each group (p < 0.05). Strength scores did not significantly increase during the third 1RM test (p = 0.22). The data indicate that the modified unilateral squat can be measured with high reliability using the 1- and 3RM tests. The improved posttest scores indicate that a pretest session should take place before recording baseline measurements.

Key Points

  • The modified unilateral squat is a reliable test for trained and untrained men and women.
  • The 1RM and 3RM tests are reliable and safe for trained and untrained subjects.
  • A practice session and pretest should be conducted prior to baseline testing.
Key words: Single-leg strength, unilateral squat, resistance exercise  相似文献   
95.
96.
Increasing research interest has focused on arterial calcification in the setting of atherosclerosis. Many features of atherosclerosis-related calcification provide useful clinical information. For example, calcium mineral deposits frequently form in atherosclerotic plaque, and intimal arterial calcification can be used as a surrogate marker for atherosclerosis; also, calcium deposits are readily and noninvasively quantified, which is useful because greater amounts of coronary calcification predict a higher risk of myocardial infarction and death. Several mechanisms leading to calcification associated with atherosclerosis have been proposed; however, no direct testing of proposed mechanisms has yet been reported. Studies in genetically altered animals and in humans have shed light on potential genetic determinants, which in turn could form the basis for a more comprehensive understanding of the factors affecting calcification within plaque and the associated pathobiologic implications. We review proposed molecular and cellular mechanisms of atherosclerosis-associated arterial calcification, summarize genetic influences, and suggest areas in which further investigation is needed. Understanding the molecular and genetic determinants of specific structural plaque components such as calcification can provide a solid foundation for the development of novel therapeutic approaches to favorably alter plaque structure and minimize vulnerability to arterial rupture.  相似文献   
97.
Glutamate excitotoxicity is strongly implicated as a major contributing factor in motor neuron degeneration in amyotrophic lateral sclerosis (ALS). Excitotoxicity results from elevated intracellular calcium ion (Ca(2+)) levels, which in turn recruit cell death signaling pathways. Recent evidence suggests that alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor subunit (GluR) stoichiometry is a dominant factor leading to excess Ca(2+) loading in neurodegeneration. In particular, the Ca(2+) permeable glutamate receptor subunit 3 (GluR3) has been implicated in several neurologic conditions such as bipolar disorder and epilepsy. Recent proteomic analysis within our group on the copper zinc superoxide dismutase (SOD1)(G93A) transgenic mouse model of familial ALS (FALS) reveals a potentially deleterious upregulation of GluR3 in spinal cord compared to that in wild-type littermates. Based on this finding we designed a 12mer antisense peptide nucleic acid (PNA) directed against GluR3. This sequence significantly reduced levels of GluR3 protein and protected neuroblastoma x spinal cord (NSC-34) cells against death induced by the AMPA receptor-specific agonist (S)-5-fluorowillardiine. We subsequently treated SOD1(G93A) mice thrice weekly with intraperitoneal injections of the antisense PNA (2.5 mg/kg) commencing at postnatal day 50. Mice treated with the antisense sequence had significantly extended survival compared to mice injected with a nonsense sequence. Western blot analysis, however, did not reveal a significant reduction in GluR3 protein levels in whole extracts of the lumbar spinal cord. These results suggest that interference with the GluR3 component of the AMPA receptor assembly may be a novel strategy for controlling excitotoxic destruction of motor neurons and may lead to new therapeutic opportunities for the treatment of human ALS.  相似文献   
98.
OBJECTIVE: The purpose of this study was to determine the experiences, satisfaction, and comfort of women with medical student participation in outpatient care during obstetric and gynecology clerkships. STUDY DESIGN: A consecutive sample of 303 women who attended the clinic were interviewed before consultation; a structured questionnaire was used. RESULTS: Two hundred sixty-four women (87.1%) accepted student involvement; 158 women (59.8%) and 173 women (66.5%), respectively, preferred female students or preceptors. Comfort levels were significantly lower with male students or preceptors in all skills that were tested (P <.0001), particularly pelvic examination and the discussion of sexual problems. Acceptance was associated significantly with older age (P <.0001), higher parity (P <.0001), higher education (P =.002), husband's occupation (P =.006), obstetric consultation (P <.0001), previous teaching encounters (P =.0006), recognition of the students' roles (P =.004), and satisfaction with clinical service (P = 0.01). Reasons for nonacceptance (n = 39 women, 12.9%) were concern about privacy during examination (53.8%) or counseling (25.6%) and the extent of the students' involvement (20.5%). CONCLUSION: Most women agreed to participate in the teaching of obstetric and gynecologic skills to medical students.  相似文献   
99.
100.
Behaviour change is an important concept in relation to health promotion and disease prevention. Self-efficacy has been identified as an important determinant of health behaviour, future health behaviour and health behaviour change. In order to effectively facilitate behaviour change, it is essential that interventions are research based, and emphasize the utility of theory in practice. The effective practice of health promotion and disease prevention requires a full understanding of the processes of patient behaviour. This article presents the role of the nurse in influencing health-related behaviour change. Self-efficacy and related but distinct theories that underpin behaviour change are discussed. The empirical evidence that supports the link between self-efficacy and predictions of health behaviours is also examined.  相似文献   
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