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991.
Gallbladder hypomotility in diabetic polyneuropathy   总被引:2,自引:0,他引:2  
This study was performed to evaluate the gallbladder motility in long-standing diabetes mellitus. The gallbladder function of diabetic patients was measured by means of quantitative hepatobiliary scintigraphy, and the severity of the associated autonomic and sensory polyneuropathy was determined. The presence of a marked gallbladder hypomotility was established, and a positive correlation was observed between the severity of the autonomic disturbance and the contractile disorder. This study underlines the important role of the neuropathy in the development of gallbladder hypomotility accompanying long-term diabetes mellitus.  相似文献   
992.
The neuropeptide somatostatin has been suggested to play an important role during neuronal development in addition to its established modulatory impact on neuroendocrine, motor and cognitive functions in adults. Although six somatostatin G protein-coupled receptors have been discovered, little is known about their distribution and function in the developing mammalian brain. In this study, we have first characterized the developmental expression of the somatostatin receptor sst2A, the subtype found most prominently in the adult rat and human nervous system. In the rat, the sst2A receptor expression appears as early as E12 and is restricted to post-mitotic neuronal populations leaving the ventricular zone. From E12 on, migrating neuronal populations immunopositive for the receptor were observed in numerous developing regions including the cerebral cortex, hippocampus and ganglionic eminences. Intense but transient immunoreactive signals were detected in the deep part of the external granular layer of the cerebellum, the rostral migratory stream and in tyrosine hydroxylase- and serotonin- positive neurons and axons. Activation of the sst2A receptor in vitro in rat cerebellar microexplants and primary hippocampal neurons revealed stimulatory effects on neuronal migration and axonal growth, respectively. In the human cortex, receptor immunoreactivity was located in the preplate at early development stages (8 gestational weeks) and was enriched to the outer part of the germinal zone at later stages. In the cerebellum, the deep part of the external granular layer was strongly immunoreactive at 19 gestational weeks, similar to the finding in rodents. In addition, migrating granule cells in the internal granular layer were also receptor-positive. Together, theses results strongly suggest that the somatostatin sst2A receptor participates in the development and maturation of specific neuronal populations during rat and human brain ontogenesis.  相似文献   
993.
This is the first of a series on pediatric pulmonary disease that will appear as Perspectives in Pediatric Pathology over the coming months. The series will include practical issues, such as this protocol for handling lung biopsies and another on bronchoalveolar lavage in childhood, as well as reviews of advances in various areas in pediatric pulmonary pathology. It has been 11 years since the last Perspectives on pulmonary disease. Much has happened since then in this area, and this collection will highlight some emerging and rapidly advancing areas in pediatric lung disease. These will include a review of molecular mechanisms of lung development, and another of mechanisms of pulmonary vascular development. The surfactant system and its disorders, as well as recent advances in the biology of the pulmonary neuroendocrine system and mechanisms of respiratory viral disease, will be addressed. Articles on pulmonary hypertension, pulmonary neoplasia, and pediatric lung transplantation, with their implications for the pediatric pathologist, are also planned. The contributors to this series are a diverse group with special interests and expertise in these areas. As Dr. William Thurlbeck noted in his foreword to the previous volume, Pulmonary Disease, volume 18 of Perspectives in Pediatric Pathology, pediatric pathology had been largely concerned with phenomenology, rather than with mechanisms, model systems, and experimental investigation. I think he would have been pleased to see the changes that have occurred over the past 10 years in pediatric lung biology and pathology in particular, because these were particularly favored interests of his later years.  相似文献   
994.
Cardioprotective effects of poly(ADP-ribose) polymerase inhibition.   总被引:2,自引:0,他引:2  
Free radical and oxidant production in cardiac myocytes during ischemia/reperfusion, cardiomyopathy, cardiotoxic drug exposure and ageing leads to DNA strand-breakage which activates the nuclear enzyme poly(ADP-ribose) polymerase (PARP) and initiates an energy consuming, inefficient cellular metabolic cycle with transfer of the ADP-ribosyl moiety of NAD+ to protein acceptors. These processes lead to the functional impairment of the myocytes and promote myocyte death. During the last decade a growing number of experimental studies demonstrated the beneficial effects of PARP inhibition in cell cultures through rodent models and more recently in pre-clinical large animal models of regional and global ischemia/reperfusion injury and various forms of heart failure. The current article provides an overview of the experimental evidence implicating PARP as a pathophysiological modulator of cardiac myocyte injury in vitro and in vivo.  相似文献   
995.
OBJECTIVE: To study the relationship of mammographic appearance of nonpalpable breast cancer to the pathologic characteristics. SUMMARY BACKGROUND DATA: The mammographic appearance of nonpalpable breast cancer may be associated with pathologic variables having prognostic significance, which could influence clinical management. METHODS: The authors correlated the mammographic appearance and pathologic characteristics of 543 nonpalpable malignancies diagnosed in a single institution between July 1993 and July 1999. Cancers were divided into four groups based on mammographic presentation: mass, calcification, mass with calcification, and architectural distortion. RESULTS: The majority of masses (95%), masses with calcifications (68%), and architectural distortions (79%) were due to invasive cancers, whereas the majority of calcifications (68%) were due to ductal carcinoma in situ (DCIS). Among invasive cancers, calcifications were associated with more extensive intraductal carcinoma, more Her2/neu immunoreactivity, and more necrosis of DCIS. Lymphatic invasion was more common in cancers presenting as a mass with calcifications. Sixty-nine percent of DCIS associated with invasive cancers presenting as calcifications were of high grade according to the European Organization for Research and Treatment of Cancer. Calcifications in noninvasive tumors were associated with necrosis in DCIS. Two thirds of cancers presenting as architectural distortion had positive margins (65%) compared with 35% to 37% of other mammographic presentations. Mammographic presentation was not significantly related to tumor differentiation or estrogen or progesterone receptor status. The ratio of invasive to noninvasive malignancies increased progressively with increasing age from 1:1 in patients younger than 50 years of age to 3:1 in patients older than 70 years, whereas the proportion presenting as calcifications declined from 63% in patients younger than 50 years to 26% in patients older than 70 years. CONCLUSIONS: Malignancies presenting as calcifications on mammography are most commonly DCIS. When invasive malignancies presented as calcifications, the calcifications were associated with accompanying high-grade DCIS, and the invasive cancers were often Her2/Neu positive. Mammographic masses with calcifications were associated with lymphatic invasion. Excisional biopsy margins were most commonly positive with architectural distortions. The mammographic appearance of nonpalpable malignancies is related to pathologic characteristics with prognostic value, which varies with patient age and influences clinical management.  相似文献   
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BACKGROUND: Patient non-compliance is a significant contributor to poor blood pressure control. Although measures to improve compliance are known, they are not in routine use. OBJECTIVE: To apply measures based on current recommendations in an integrated approach in the 'Manage it well!' (MIW) programme, and to determine the improvement in blood pressure control. DESIGN AND SETTING: During the prospective open cohort study, 348 primary and 156 secondary care centres enrolled 6941 hypertensive patients and followed them for 6 months. INTERVENTIONS: An integrated intervention package also applicable to everyday practice was introduced to improve treatment adherence, including education programmes for patients and physicians, tight follow-up with frequent office visits and regular home blood pressure measurements. Treatment was based on either trandolapril or verapamil SR with dose titration, with added-on therapy if necessary. MAIN OUTCOME MEASURE: Rates of control of blood pressure to < 140/90 mmHg. RESULTS: Data were evaluated from 5468 patients, 72% known to have hypertension and 26% newly diagnosed [2% not available (n.a.)]. At baseline only 2.9% of treated patients had their hypertension well controlled (< 140/90 mmHg), but during the programme this increased to 40.9% (P < 0.001). The absolute reduction in office blood pressure was also significant (from 168 +/- 19/97 +/- 11 mmHg to 139 +/- 13/83 +/- 7 mmHg; P < 0.001). No differences in blood pressure control were found between trandolapril and verapamil SR regimens. Office blood pressure was greater than home blood pressure at baseline (168 +/- 19/97 +/- 11 mmHg compared with 151 +/- 17/89 +/- 10 mmHg; P < 0.001), but this difference disappeared at 6 months (139 +/- 13/83 +/- 7 mmHg compared with 140 +/- 13/84 +/- 7 mmHg, respectively). CONCLUSIONS: The integrated, patient-focused approach used in the MIW programme significantly increases the success of treatment in a 'real-world' setting.  相似文献   
1000.
To explore the effect of refeeding on recovery of TRH gene expression in the hypothalamic paraventricular nucleus (PVN) and its correlation with the feeding-related neuropeptides in the arcuate nucleus (ARC), c-fos immunoreactivity (IR) in the PVN and ARC 2 h after refeeding and hypothalamic TRH, neuropeptide Y (NPY) and agouti-related protein (AGRP) mRNA levels 4, 12, and 24 h after refeeding were studied in Sprague-Dawley rats subjected to prolonged fasting. Despite rapid reactivation of proopiomelanocortin neurons by refeeding as demonstrated by c-fos IR in ARC alpha-MSH-IR neurons and ventral parvocellular subdivision PVN neurons, c-fos IR was present in only 9.7 +/- 1.1% hypophysiotropic TRH neurons. Serum TSH levels remained suppressed 4 and 12 h after the start of refeeding, returning to fed levels after 24 h. Fasting reduced TRH mRNA compared with fed animals, and similar to TSH, remained suppressed at 4 and 12 h after refeeding, returning toward normal at 24 h. AGRP and NPY gene expression in the ARC were markedly elevated in fasting rats, AGRP mRNA returning to baseline levels 12 h after refeeding and NPY mRNA remaining persistently elevated even at 24 h. These data raise the possibility that refeeding-induced activation of melanocortin signaling exerts differential actions on its target neurons in the PVN, an early action directed at neurons that may be involved in satiety, and a later action on hypophysiotropic TRH neurons involved in energy expenditure, potentially mediated by sustained elevations in AGRP and NPY. This response may be an important homeostatic mechanism to allow replenishment of depleted energy stores associated with fasting.  相似文献   
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