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991.
992.
PURPOSE: Women with epilepsy have increased frequency of reproductive health problems compared to women without epilepsy. In puberty, reproductive hormonal changes during sexual maturation may affect epilepsy and induce the debut of seizures as indicated in some studies. On the other hand, epileptic activity affects sex hormone function, which may induce alterations in pubertal endocrine maturation and thereby menarche age. We wanted to investigate the relation between epilepsy and menarche age in a larger population of female epilepsy patients. METHODS: A retrospective, questionnaire study of a cohort of 265 female outpatients from three Norwegian hospitals and 142 controls, aged 18-45 years was conducted. Parameters regarding epilepsy and reproductive health issues were registered. Perimenarche was defined as 2 years before and 2 years after the year of menarche. RESULTS: There was a significantly higher frequency of patients with epilepsy debut between 10 and 18 year compared to 0-9 years (p<0.01). There was, however, no significant difference in occurrence of epilepsy debut in the perimenarche period compared to the 5 year periods before and after perimenarche, and no significant difference in epilepsy debut in the year of menarche compared to the 5 years before or after. Menarche age was not significantly different in those with epilepsy debut before or after menarche. Epilepsy type (idiopathic generalised or partial) did not influence the menarche age. CONCLUSIONS: The study did not confirm the former observations of clustering of epilepsy debut at menarche or in the perimenarche period or alterations in menarche age in girls with epilepsy. However, onset of epilepsy is more frequent in the adolescent years (10-18), than in childhood (0-9).  相似文献   
993.
This paper describes an approach and technical process for developing and implementing a Control Strategy, which is a planned set of controls, derived from current product and process understanding that assures process performance and product quality. Development of a Control Strategy requires a structured process, involving a multi-disciplinary team of experts, linking pharmaceutical development to the manufacturing process, and engineering controls of process equipment. The PQLI Control Strategy Team has proposed a Control Strategy Model that facilitates understanding and that may be used a cross-functional communication tool. This paper concentrates on the techniques and principles involved in developing the early Control Strategy rather than the operational implementation of the strategy. Tom Garcia - Pfizer, Stephen Tyler - Abbott, Eric Ahuja - Merck, Metter Bryder - Lundbeck, Michael Hahn - Lundbeck, Ray Bolton - AstraZeneca, Gordon Muirhead - GSK, Sue Busse - Lilly, Hedinn Valthorsson - Novartis  相似文献   
994.
To improve outcomes in small cell lung cancer (SCLC), the rationale for treatment intensification is to overcome the occurrence of drug resistance. To achieve a more than twofold increase in dose intensity, some kind of stem cell support is mandatory. However, the benefit of an escalation of chemotherapy doses with stem cell support in SCLC is still unproven, and many oncologists believe this approach should probably be abandoned. In this article, we review and comment on the data that have been reported so far. The high number of novel targeted agents available for evaluation in SCLC provides new optimism that progress will be made over the next decades. We review the reported phase II and phase III trials of targeted agents conducted in patients with SCLC. Numerous compounds have failed to demonstrate efficacy, but results from trials with bevacizumab and multikinase inhibitors such as sorafenib and sunitinib are awaited with interest.  相似文献   
995.
The opening of intracellular potassium channels has been suggested as a mechanism regulating hair growth. Enhancing the flux of potassium ions is a mechanism shared by several structurally diverse antihypertensive agents including minoxidil sulfate (the active metabolite of minoxidil), pinacidil, P-1075 (a potent pinacidil analog), RP-49,356, diazoxide, cromakalim, and nicorandil. Of these drugs, minoxidil, pinacidil, and diazoxide have been reported to elicit hypertrichosis in humans. This potassium channel hypothesis was examined by testing these drugs for effects on hair growth both in vitro and in vivo. For the in vitro studies, mouse vibrissae follicles were cultured for 3 d with drug and the effects on hair growth were measured by metabolic labeling. All drugs, except diazoxide, enhanced cysteine incorporation into the hair shafts of the cultured vibrissae. Diazoxide was poorly soluble and thus was tested only at low doses. Minoxidil, P-1075, cromakalim, and RP-49,356 were also evaluated in vivo by measuring hair growth effects in balding stumptail macaque monkeys. The drugs were administered topically to defined sites on balding scalps once per day for 4-5 months and the amount of hair grown was determined by monthly measurements of shaved hair weight. Three of the drugs produced significant increases in hair weight whereas, the RP-49,356 had no effect. These studies provide correlative evidence that the opening of potassium channels is an important regulatory mechanism for hair growth. This provides the impetus for further studies on this potentially important mechanism affecting hair biology.  相似文献   
996.
OBJECTIVES: The objective of this study was to compare heart rate variability (HRV) in patients with essential hypertension, in patients with white-coat hypertension and in normotensive control individuals, and to investigate a possible relation between HRV and vasoactive hormones. METHODS: Patients with essential hypertension (n=19, 61 years, median and interquartile range: 40-66 years), patients with white-coat hypertension (n=8, 52 years, median and interquartile range: 41-64 years) and normotensive participants (n=13, 50 years, median and interquartile range: 39-57 years) participated in the study. HRV was measured at rest in the supine position, during standing and during controlled forced breathing (respiration frequency >20/min). Power spectral density was calculated using Fourier transformation. RESULTS: Controlled breathing caused a decrease in low frequency (LF) variation and LF/high frequency variation (LF/HF) in all blood pressure groups. The decrease in LF was smaller in the hypertensive group (-60 ms2) than in the normotensive group (-139 ms2) (P=0.03; hypertensive group vs. normotensive group). The decrease in LF/HF induced by controlled breathing was -0.9 ms in the hypertensive group, -2.0 ms2 in the white-coat hypertensive group and -2.8 ms2 in the normotensive group, (P=0.037; hypertensive group vs. normotensive group). We found a positive correlation between baseline plasma renin concentration and LF (r=0.330, P=0.037) and LF/HF (r=0.378, P=0.016) at rest. CONCLUSION: The observed differences in HRV might reflect the impaired responsiveness to autonomic challenge in hypertensive patients. We did not find the HRV spectrum in white-coat hypertension different from the HRV spectrum in hypertension or normotension.  相似文献   
997.
998.

Background

Glioblastomas are primary malignant brain tumors with a dismal prognosis. Knowledge of growth rates and underlying growth dynamics is useful for understanding basic tumor biology, developing realistic tumor models, and planning treatment logistics.

Methods

By using repeated pretreatment contrast-enhanced T1-weighted MRI scans from 106 patients (aged 26–83 years), we studied the growth dynamics of untreated glioblastomas in vivo. Growth rates were calculated as specific growth rates and equivalent volume doubling times. The fit of different possible growth models was assessed using maximum likelihood estimations.

Results

There were large variations in growth rates between patients. The median specific growth rate of the tumors was 1.4% per day, and the equivalent volume doubling time was 49.6 days. Exploring 3 different tumor growth models showed similar statistical fit for a Gompertzian growth model and a linear radial growth model and worse fit for an exponential growth model. However, large tumors had significantly lower growth rates than smaller tumors, supporting the assumption that glioblastomas reach a plateau phase and thus exhibit Gompertzian growth.

Conclusion

Based on the fast growth rate of glioblastoma shown in this study, it is evident that poor treatment logistics will influence tumor size before surgery and can cause significant regrowth before adjuvant treatment. Since there is a known association between tumor volume, extent of surgical resection, and response to adjuvant therapy, it is likely that waiting times play a role in patient outcomes.  相似文献   
999.
BACKGROUND: Soot particles are air pollutants capable of inducing airway and lung parenchymal injury. Mononuclear and bronchial epithelial cells are central to the maintenance of homeostasis and inflammation in the airways. OBJECTIVES: The aim of this study was to evaluate the contribution of mononuclear cells to the release of inflammatory mediators by bronchial epithelial cells. Methods: To model the in vivo situation, an in vitro system of cocultured blood monocytes and BEAS-2B cells was established in a transwell system. Blood monocytes were exposed to soot particles (FR 101) at concentrations of up to 100 microg/10(6) cells. Inflammatory cytokine mRNA and protein concentrations were quantified in BEAS-2B mono- and BEAS-2B-BM cocultures by RT-PCR and ELISA following exposure to soot for 1 and 8 h. RESULTS: No inflammatory cytokine mRNA expression was observed in unstimulated BEAS-2B cells. IL-6 and IL-8 mRNA and protein levels showed a dose-dependent elevation in FR 101-exposed blood monocytes. In addition, both IL-6 and IL-8 mRNA expression was upregulated in cocultured BEAS-2B cells while cytokine concentrations in the blood monocyte-BEAS-2B coculture medium were significantly increased. This upregulation was likely due to a synergism of two cell populations. CONCLUSIONS: Exposure to soot particles induces an autocrine stimulation of inflammatory cytokine release by blood monocytes and BEAS-2B cells. Since IL-6 and IL-8 play a major role in the pathogenesis and persistence of bronchial inflammation, these findings may serve as a partial explanation for the aggravation of asthmatic and bronchitic symptoms after exposure to soot.  相似文献   
1000.
Phagocytes are a critical component of the innate immune response in humans and eliminate invading microorganisms through a process known as phagocytosis. Two distinct receptor-linked phagocytic pathways, one with Ab receptors (FcRs; FcR, Fc receptor) and the other complement receptors (CRs), mediate binding and ingestion of pathogens by human polymorphonuclear leukocytes (PMNs). Although progress has been made toward defining complex signal transduction processes that underlie phagocytosis in each pathway, very little is known about gene regulation during or after phagocytosis. Therefore, we used human oligonucleotide microarrays to identify changes in expression of 12,561 genes accompanying FcR- and CR-mediated phagocytosis. Eighty-four percent of 279 differentially expressed genes were induced or repressed 90 min after ingestion of Ab- and/or complement-opsonized particles. Unexpectedly, more than 30 of these genes encoded proteins involved in at least three distinct apoptotic pathways. Ninety-four differentially expressed cell fate-related genes were identified between 180 and 360 min after phagocytosis and most were induced or repressed by PMNs activated through both receptors simultaneously. By using flow cytometry, we found that FcR- and CR-mediated phagocytosis each promoted programmed cell death in human PMNs; however, phagocytosis mediated by the combination of FcRs and CRs induced apoptosis earlier than that by either receptor alone. Our results reveal distinct patterns of receptor-mediated gene expression that define complex inducible apoptotic pathways in activated PMNs. Most significantly, we discovered that programmed cell death is regulated at the level of gene expression. Thus, we hypothesize that gene regulation in PMNs facilitates resolution of inflammatory responses.  相似文献   
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