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991.
Lipid peroxidation in biological systems has been considered as one of the major mechanisms of cell injury in aerobic organisms subjected to oxidation stress. Plants, among other functions, are considered to act as free radical scavengers and as antioxidants. Iron II (Fe2+), sodium nitroprusside (SNP) and nitropropionic acid stimulate the production of free radicals and lipid peroxidation. In this study, four commonly used tropical medicinal plants (Kigelia africana, Calotropis procera, Hibiscus sabdariffa and Alchornea cordifolia) were studied (in vitro) for their effects on the formation of thiobarbituric acid reactive substances (TBARS) induced by different pro-oxidants (10 μM FeSO4, 5 μM -sodium SNP and 2 mM 3-nitropropionic acid) in rat liver homogenate. All the pro-oxidants significantly increased (P<0.05) the formation of TBARS, which indicates increased lipid peroxidation in the rat liver (in vitro). However, all the plant extracts statistically (P<0.05) reduced the production of TBARS in a concentration-dependent manner in all the tested pro-oxidant-induced oxidative stresses. Alchornea cordifolia appeared to offer the highest protection. The results of the present study suggest that the use of these plants in the treatment of various diseases, especially liver disease, is probably due to their ability to act as antioxidants.  相似文献   
992.
CD8+ cells from human immunodeficiency virus type 1 (HIV-1) infected individuals have been shown to suppress HIV-1 replication both through a major histocompatibility complex (MHC)-restricted cytolytic pathway as well as through a noncytolytic pathway mediated through soluble factors. To characterize this soluble activity and its potential role in disease progression further, we studied the HIV-1 inhibition by supernatants derived from herpesvirus saimiri-transformed CD8+ cells isolated from infected children. Three of the six CD8+ cell lines derived had a phenotype consistent with an unusual natural killer (NK) cells phenotype with low CD3, high CD56, and low CD16. Supernatants from some of the cell lines derived from children with rapid progression as well as long-term nonprogressors exhibited broad HIV-1-inhibitory activity in primary CD4+ cells as well as in primary macrophages. In contrast to a cocktail of beta-chemokines, the supernatants inhibited T-tropic as well as M-tropic viruses, efficiently inhibited infection in primary macrophages, and inhibited HIV-1 activation in the chronically infected U1 cell line. The HIV-1-inhibitory activity was heat stable and active over a broad pH range. Fractionation of the supernatant by size and ion exchange chromatography demonstrated activity in the complete absence of RANTES as well as interferons-alpha, beta, and gamma and in a size range of less than 10 kD and greater than 3 kD. CD8+ cell supernatants contain additional unidentified factors that have anti-HIV activity to account for this broad phenomenon.  相似文献   
993.
The blood supply of the Papillary Muscle (PM) of the left ventricle, cranial (PM) and caudal (PM), in Hereford cattle was studied. The results obtained from the dissection of 50 hearts injected with neoprene latex, indicated that the cranial PM is supplied by collateral of the Ramus descendens paraconalis in all cases, alone or together with vessels from the Ramus circumflexus of the Arteria coronaria sinistra. The caudal PM is supplied from arteries coming mainly from the Ramus circumflexus of the A. coronaria sinistra, and also from the Ramus descendens subsinuosus and Ramus descendens paraconalis. When present, the A. diagonalis supplies the cranial PM and in some cases the caudal PM too. Thus this vessel can be termed "artery of the papillary muscle".  相似文献   
994.
Musculoskeletal injuries are very frequent and are responsible for causing pain and impairment of muscle function, as well as significant functional limitations. In the acute phase, the most prescribed treatment is with non-steroidal anti-inflammatory drugs (NSAIDs), despite their questionable effectiveness. However, the use of photobiomodulation therapy (PBMT) in musculoskeletal disorders has been increasing in the last few years, and this therapy appears to be an interesting alternative to the traditional drugs. The objective of the present study was to evaluate and compare the effects of PBMT, with different application doses, and topical NSAIDs, under morphological and functional parameters, during an acute inflammatory process triggered by a controlled model of musculoskeletal injury induced via contusion in rats. Muscle injury was induced by means of a single trauma to the animals’ anterior tibialis muscle. After 1 h, the rats were treated with PBMT (830 nm; continuous mode, with a power output of 100 mW; 3.57 W/cm2; 1 J–35.7 J/cm2, 3 J–107.1 J/cm2, and 9 J–321.4 J/cm2; 10, 30, and 90 s) or diclofenac sodium for topical use (1 g). Morphological analysis (histology) and functional analysis (muscle work) were performed, 6, 12, and 24 h after induction of the injury. PBMT, with all doses tested, improved morphological changes caused by trauma; however, the 9 J (321.4 J/cm2) dose was the most effective in organizing muscle fibers and cell nuclei. On the other hand, the use of diclofenac sodium produced only a slight improvement in morphological changes. Moreover, we observed a statistically significant increase of muscle work in the PBMT 3 J (107.1 J/cm2) group in relation to the injury group and the diclofenac group (p < 0.05). The results of the present study indicate that PBMT, with a dose of 3 J (107.1 J/cm2), is more effective than the other doses of PBMT tested and NSAIDs for topical use as a means to improve morphological and functional alterations due to muscle injury from contusion.  相似文献   
995.
Muscle injuries trigger an inflammatory process, releasing important biochemical markers for tissue regeneration. The use of non-steroidal anti-inflammatory drugs (NSAIDs) is the treatment of choice to promote pain relief due to muscle injury. NSAIDs exhibit several adverse effects and their efficacy is questionable. Photobiomodulation therapy (PBMT) has been demonstrated to effectively modulate inflammation induced from musculoskeletal disorders and may be used as an alternative to NSAIDs. Here, we assessed and compared the effects of different doses of PBMT and topical NSAIDs on biochemical parameters during an acute inflammatory process triggered by a controlled model of contusion-induced musculoskeletal injury in rats. Muscle injury was induced by trauma to the anterior tibial muscle of rats. After 1 h, rats were treated with PBMT (830 nm, continuous mode, 100 mW of power, 35.71 W/cm2; 1, 3, and 9 J; 10, 30, and 90 s) or diclofenac sodium (1 g). Our results demonstrated that PBMT, 1 J (35.7 J/cm2), 3 J (107.1 J/cm2), and 9 J (321.4 J/cm2) reduced the expression of tumor necrosis factor alpha (TNF-α) and cyclooxygenase-2 (COX-2) genes at all assessed times as compared to the injury and diclofenac groups (p < 0.05). The diclofenac group showed reduced levels of COX-2 only in relation to the injury group (p < 0.05). COX-2 protein expression remained unchanged with all therapies except with PBMT at a 3-J dose at 12 h (p < 0.05 compared to the injury group). In addition, PBMT (1, 3, and 9 J) effectively reduced levels of cytokines TNF-α, interleukin (IL)-1β, and IL-6 at all assessed times as compared to the injury and diclofenac groups (p < 0.05). Thus, PBMT at a 3-J dose was more effective than other doses of PBMT and topical NSAIDs in the modulation of the inflammatory process caused by muscle contusion injuries.  相似文献   
996.
997.
998.
Proteinuria is an important biomarker commonly used to detect and manage kidney disease in children. There are now a variety of methods available to measure urinary protein loss, and physicians are faced with several contrasting strategies: 24‐h or timed collection versus spot samples (first‐morning or random), measurement of total urinary protein versus selective measurement of urinary albumin, unadjusted urine protein concentration versus protein‐to‐creatinine ratio and the use of dipstick versus laboratory‐based methods. In this review, we will discuss the advantages and disadvantages of these different approaches. We will then summarise the evidence base for proteinuria as a clinical biomarker in different settings, including discussion of the current and potential role of measuring low‐level albuminuria. Finally, we will highlight gaps in the literature and opportunities for further research into proteinuria among children.  相似文献   
999.

Introduction and hypothesis

The aim of this study was to evaluate the correlations between the POP-Q Bp point and the perineal body (Pb) and genital hiatus (Gh) measurements and constipation, anal incontinence, severity of symptoms and quality of life.

Methods

The patients were distributed into two groups according to the posterior vaginal wall Bp point: one group with Bp ≤?1 (without posterior vaginal wall prolapse, control group) and the other group with Bp ≥0 (with posterior vaginal wall prolapse, case group). Demographic data, defecatory dysfunction and SF-36 scores were compared between the groups. Correlations between severity of posterior prolapse (Bp, Gh, Pb and Gh?+?Pb) and severity of bowel symptoms were also calculated.

Results

A total of 613 women were evaluated, of whom 174 were included, 69 (39.7%) in the control group and 105 (60.3%) in the case group. The groups were similar in terms of anal incontinence, fecal urgency and/or constipation. There was no correlation between the severity of constipation and anal incontinence according to the Wexner score, and the severity of posterior vaginal wall prolapse measured in terms of point Bp. There were, however, statistically significant differences in Pb, Gh and Gh?+?Pb between the groups. The Pb and Gh?+?Pb measurements were positively correlated with symptoms of constipation, as well as with the scores of some SF-36 domains, but were not correlated with anal incontinence.

Conclusions

These results suggest that the severity of posterior vaginal wall prolapse is not correlated with constipation or anal incontinence, but Pb and Gh?+?Pb measurements are correlated with constipation and SF-36 scores.
  相似文献   
1000.
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