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91.
L Schmued P Phermsangngam H Lee S Thio E Chen P Truong E Colton J Fallon 《Brain research》1989,487(1):131-142
The first phase of this study involves injecting a different fluorescent retrograde axonal tracer into the subthalamic nucleus, the substantia nigra, and the mesopontine tegmentum. Multiple labeled cells are found within the caudal third of the globus pallidus. The entopeduncular nucleus and adjacent basal forebrain structures such as the substantia innominata, lateral hypothalamus, bed nucleus of the stria terminalis, and central nucleus of the amygdala all exhibit some dye containing cell, although multiple labeled cells are rare. The second phase of this study involves injecting a different fluorescent retrograde tracer into either the substantia nigra, or the mesopontine tegmentum, and subsequent processing of the tissue for glutamic acid decarboxylase (GAD) immunocytochemistry. Many dye and antibody double-labeled cells could be found within the entopeduncular nucleus and the caudal third of the globus pallidus. This is in contrast to the surrounding basal forebrain regions with brainstem efferents which were rarely GAD-positive. This study indicates that the collateral pattern and immunocytochemistry of globus pallidus neurons with descending efferents are distinct from other basal forebrain neurons having similar efferents. These results also extend previous findings and suggest that the neuron of the pallidal complex are heterogeneous with respect to their patterns of projections. In particular, the present findings question previous assumptions concerning the homology of pallidal segments between primate and rodent species. 相似文献
92.
BACKGROUND: Adjuvant therapy for women with T1-T2 breast carcinoma and 1-3 positive lymph nodes is controversial due to discrepancies in reported baseline locoregional recurrence (LRR) risks. This inconsistency has been attributed to variations in lymph node staging techniques, which have yielded different numbers of dissected lymph nodes. The current study evaluated the prognostic impact of the percentage of positive/dissected lymph nodes on recurrence and survival in women with one to three positive lymph nodes. METHODS: The study cohort was comprised of 542 women with pathologic T1-T2 breast carcinoma who had 1-3 positive lymph nodes and who had undergone mastectomy and received adjuvant systemic therapy without radiotherapy. Ten-year Kaplan-Meier (KM) LRR, distant recurrence (DR), and overall survival (OS) rates stratified by the number of positive lymph nodes, the number of dissected lymph nodes, and the percentage of positive lymph nodes were examined using different cut-off levels. Multivariate analysis was performed to evaluate the prognostic significance of the percentage of positive lymph nodes in disease recurrence and survival. RESULTS: The median follow-up was 7.5 years. LRR, DR, and OS rates correlated significantly with the number of positive lymph nodes and the percentage of positive lymph nodes, but not with the number of dissected lymph nodes. The cut-off level at which the most significant difference in LRR was observed was 25% positive lymph nodes (the 10-year KM LRR rates were 13.9% and 36.7% in women with < or = 25% and > 25% positive lymph nodes, respectively; P < 0.0001). Higher DR rates and lower OS rates were observed among patients who had > 25% positive lymph nodes compared with patients who had < or = 25% positive lymph nodes (DR: 53.0% vs. 30.3%, respectively; P < 0.0001; OS: 43.4% vs. 62.6%, respectively; P < 0.0001). In the multivariate analysis, the percentage of positive lymph nodes and the histologic grade were significant, independent factors associated with LRR, DR, and OS. CONCLUSIONS: The presence of > 25% positive lymph nodes was an adverse prognostic factor in patients with 1-3 positive nodes and may be used to identify patients at high risks of postmastectomy locoregional and distant recurrence who may benefit with adjuvant radiotherapy and more aggressive systemic therapy regimens. 相似文献
93.
Long DA Newaz MA Prabhakar SS Price KL Truong LD Feng L Mu W Oyekan AO Johnson RJ 《Kidney international》2005,68(5):2154-2163
BACKGROUND: Aging has considerable structural and functional effects on the vascular system of the kidney. One such effect is an alteration in vascular tone which potentially will initiate renal damage. Vascular tone is determined by the balance between vasoconstrictors and vasodilators. Therefore, we hypothesized that aging attenuates vasodilatory responses in the kidney. These changes may be mediated by a loss of nitric oxide and endothelial-derived hyperpolarizing factor (EDHF). METHODS: The systemic and renal responses of nitric oxide and EDHF were investigated in aging (18 months old) and young (3 months old) Sprague-Dawley rats. RESULTS: We demonstrated a general loss of vasodilatory responses in the aging kidney. In addition, nitric oxide levels were reduced in the serum and kidney cortex of aging versus young animals, although this was not accompanied with a loss of endothelial nitric oxide synthase (eNOS) protein in the kidney cortex. Aging animals also exhibited a loss in EDHF-mediated vasodilation following stimulation with either acetylcholine or bradykinin in the isolated perfused kidney. CONCLUSION: These findings indicate that not only a defect in the nitric oxide pathway, but also a loss of EDHF-mediated responses may be responsible for impaired vasodilation in the aging kidney. This may result in enhanced vasoconstrictive responses in aging which potentially will cause renal damage and ultimately a loss in glomerular filtration rate (GFR). 相似文献
94.
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96.
Vu SN Nguyen TY Tran VP Truong UN Le QM Le VL Le TN Bektas A Briscombe A Aaskov JG Ryan PA Kay BH 《The American journal of tropical medicine and hygiene》2005,72(1):67-73
From September 2000 to June 2003, a community-based program for dengue control using local predacious copepods of the genus Mesocyclops was conducted in three rural communes in the central Vietnam provinces of Quang Nam, Quang Ngai, and Khanh Hoa. Post-project, three subsequent entomologic surveys were conducted until March 2004. The number of households and residents in the communes were 5,913 and 27,167, respectively, and dengue notification rates for these communes from 1996 were as high as 2,418.5 per 100,000 persons. Following knowledge, attitude, and practice evaluations, surveys of water storage containers indicated that Mesocyclops spp. already occurred in 3-17% and that large tanks up to 2,000 liters, 130-300-liter jars, wells, and some 220-liter metal drums were the most productive habitats for Aedes aegypti. With technical support, the programs were driven by communal management committees, health collaborators, schoolteachers, and pupils. From quantitative estimates of the standing crop of third and fourth instars from 100 households, Ae. aegypti were reduced by approximately 90% by year 1, 92.3-98.6% by year 2, and Ae. aegypti immature forms had been eliminated from two of three communes by June 2003. Similarly, from resting adult collections from 100 households, densities were reduced to 0-1 per commune. By March 2004, two communes with no larvae had small numbers but the third was negative; one adult was collected in each of two communes while one became negative. Absolute estimates of third and fourth instars at the three intervention communes and one left untreated had significant correlations (P = 0.009-< 0.001) with numbers of adults aspirated from inside houses on each of 15 survey periods. By year 1, the incidence of dengue disease in the treated communes was reduced by 76.7% compared with non-intervention communes within the same districts, and no dengue was evident in 2002 and 2003, compared with 112.8 and 14.4 cases per 100,000 at district level. Since we had similar success in northern Vietnam from 1998 to 2000, this study demonstrates that this control model is broadly acceptable and achievable at community level but vigilance is required post-project to prevent reinfestation. 相似文献
97.
Vinh H Duong NM Phuong le T Truong NT Bay PV Wain J Diep TS Ho VA White NJ Day NP Parry CM 《Annals of tropical paediatrics》2005,25(1):17-22
An open, randomised comparison of 2 or 3 days of oral ofloxacin (10 mg/kg/day) for uncomplicated typhoid fever was conducted in 235 Vietnamese children. Multi-drug-resistant Salmonella typhi was isolated from 182/202 (90%) children and 5/166 (3%) tested isolates were nalidixic acid-resistant (Na(R)). Eighty-nine of 116 children randomised to 2 days and 107/119 randomised to 3 days were blood culture-positive and eligible for analysis. There were 12 (13.5%) failures in the 2-day group (six clinical failures, four blood culture-positive post treatment, two relapses) compared with eight (7.5%) failures in the 3-day group (four clinical failures, one blood culture-positive post treatment, three relapses) (OR 1.9, 95% CI 0.7-5.5,p = 0.17). There were no significant differences in the mean (95% confidence interval) fever clearance times (h) [92 (82-102) vs 101 (93-110), p = 0.18] or duration of hospitalisation (d) [7.6 (7.2-8.1) vs 8.0 (7.6-8.4), p = 0.19] between the two groups. There was one failure in the four eligible children infected with an Na(R) isolate of S. typhi. No adverse events were attributable to the ofloxacin. These results extend previous observations on the efficacy of short courses of ofloxacin for children with uncomplicated multi-drug-resistant typhoid fever. 相似文献
98.
Post-hypoxic myoclonus induces Fos expression in the reticular thalamic nucleus and neurons in the brainstem 总被引:4,自引:0,他引:4
Post-hypoxic myoclonus is a movement disorder characterized by brief, sudden involuntary muscle jerks. Although the mechanism underlying this disorder remains unclear, earlier pharmacological studies indicated that aberrant activity of specific neuronal circuitry in the central nervous system causes this disorder. In the present study, Fos protein, an immediate-early gene product, was used as a marker of neuronal activity to identify the brain nuclei possibly involved in post-hypoxic myoclonus. We found that Fos protein was immunologically detected in the reticular thalamic nucleus (RT), the medial longitudinal fasciculus (MLF) as well as in the locus coeruleus (LC) and the periventricular gray substance (PVG) in post-hypoxic rats that developed myoclonus in response to auditory stimuli. Fos was not detected in these nuclei from rats that underwent 4 min of cardiac arrest without myoclonus. Electrolytic lesions of the RT or MLF but not the LC/PVG significantly reduced auditory stimulated myoclonus in the post-hypoxic rats. The results suggest that neuronal activity in the RT and the MLF plays a contributing role in post-hypoxic myoclonus. 相似文献
99.
100.
On antenatal ultrasound assessment, an apparently solitary hydronephrotic kidney was identified, confirmed on postnatal ultrasound examination. More detailed postnatal investigations revealed the diagnosis of crossed renal ectopia. 相似文献