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Eileen J. Martin Kiran S. Panickar Michael A. King Malgorzata Deyrup Bruce E. Hunter Geehuan Wang Edwin M. Meyer 《Drug development research》1994,31(2):135-141
The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc. 相似文献
3.
Anna Plachcinska Jacek Kusmierek Maciej Kosmider Malgorzata Bienkiewicz Julian Liniecki 《European journal of nuclear medicine and molecular imaging》1995,22(3):193-200
A quantified evaluation of planar cardiac perfusion scintigrams (the objective of the study), obtained using technetium-99m methoxyisobutylisonitrile (MIBI) was performed on the basis of an analysis of circumferential profile curves, representing the perfusion as seen in three typical projections. The analysis involved the curves obtained both at rest and after stress, and was based on a comparison of their shape (trend) with the normal trend (normative evaluation). The latter was obtained by means of an original method of iterative fitting of individual curves into the database. The base consisted of curves recorded in 53 patients (separately in males and females) with normal perfusion of the left ventricle (group I, the reference group). A group of 90 patients suspected of having coronary artery disease (group II) was subdivided into two subgroups on the basis of coronary arteriography: (a) those with and (b) those without critical stenosis of at least one artery. Profile curves characterising the LV perfusion were obtained at rest and after stress. Defects of perfusion were quantified by comparison of individual curves with the normal trends. By means of multivariate analysis it was demonstrated that vectors of mean values characterising the scintigraphically assessed defects of LV perfusion in the two subgroups of group II differed very significantly (P<10–5). Applying methods of discriminant analysis, a classification of patients from group II was performed into those with probable defects of perfusion and those free of such defects. The sensitivity, specificity and accuracy of diagnosis of coronary ischaemia, based on quantified planar99mTc-MIBI scintigraphy, reached 86%, 87% and 87%, respectively. 相似文献
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13C-NMR and the electron impact mass spectra of the β-carboline derivatives 1 – 18 were examined. The structure of the possible diastereomers is discussed. A quantitative relationship between the relative intensity of ions a in the mass spectra of 1 – 18 and the structure of substituents R was found. 相似文献
6.
Summary: The present study was undertaken in the hope that conflicting opinions concerning interrelationships among minimal change disease (MCD), mesangial proliferative glomerulonephritis (MPG) and focal segmental glomeruloscierosis (FSGS) might be elucidated by morphometric methods performed by image analysis, as well as to study whether serum creatinine and changes in quantitatively analysed glomeruli could correlate with the interstitial fibrosis in these glomerulopathies. Fifteen renal biopsy specimens from children with MCD, 10 with primary MPG and 12 with FSGS for whom both light and electron microscopy as well as immunofluorescence microscopy and full clinical data were available, were examined quantitatively. As a control five biopsy and 10 autopsy specimens of the normal kidneys were used. Our quantitative study showed that in MCD, MPG and FSGS glomerular and interstitial values differed from normal. Morphometric differences between MPG and both MCD and FSGS groups were also shown. Although the mean values of total glomerular area and relative interstitial volume were increased in FSGS patients, in total glomerular cells per unit of glomerular area and mesangium (% of total glomerular area) were similar in both MCD and FSGS groups. In MPG strong positive correlations existed between interstitial volume and serum creatinine, interstitial volume and total glomerular cells per unit of glomerular area as well as between interstitial volume and glomerular mesangium (% of total glomerular area). In FSGS there was significant positive correlation between interstitial volume and serum creatinine. In the MCD group all correlations were weak and not significant. In conclusion, our morphometric studies suggest a close relationship between MCD and FSGS, and indicate that MPG is a separate morphologic entity in children. 相似文献
7.
Malgorzata Krajewska Walasek Anna Gutkowska Beata Bieliska Bozenna Goryluk-Kozakiewicz Ewa Popowska 《Clinical genetics》1998,54(1):60-64
We report on a case of Prader-Willi syndrome (PWS) with a true reciprocal unbalanced translocation, 45,XX,-15,der(11)t(11;15)pat. The proposita was diagnosed clinically as having severe PWS. Molecular studies revealed loss of the paternal methylation pattern at locus D15S63 and a deletion encompassing the loci from at least D15S10 to D15S97 of paternal chromosome 15. FISH studies confirmed the deletion of 15q11-q13 region and the presence of two telomeres on all chromosomes. The proposita's father, the father's sister and their mother are all carriers of the same balanced translocation t(11;15)(q25;q13). By genomic imprinting we would expect that if the father's sister were to give birth to a child with the same unbalanced translocation as the proband, it would be affected by Angelman syndrome.
To date, a similar familial unbalanced translocation due to loss of the small chromosome 15 derivative has not been described. 相似文献
To date, a similar familial unbalanced translocation due to loss of the small chromosome 15 derivative has not been described. 相似文献
8.
Malgorzata Mrugacz Maciej Kaczmarski Alina Bakunowicz-Lazarczyk Beata Zelazowska Jolanta Wysocka Alina Minarowska 《Journal of interferon & cytokine research》2006,26(2):71-75
Cystic fibrosis (CF) is inherited as an autosomal recessive disorder. It is caused by mutations in the protein-coding gene of chromosome 7, resulting in chronic pulmonary disease and pancreatic insufficiency. The disease affects all secretory epithelia, including the eye. The pathogenesis of ocular changes in CF is still unknown, but the involvement of immunologic processes in patients with CF has been studied in recent years. We measured interleukin-8 (IL-8) and interferon-gamma (IFN-gamma) levels in tears in a group of patients and a group of normal controls to determine if the levels of these cytokines are elevated in CF. The levels of these cytokines in tears and the clinical severity of CF and eye disease were compared. Tear samples were collected from 24 patients with CF at the department of pediatric diseases, Medical University of Bialystok, Poland. Cytokine levels were determined by ELISA. Ophthalmic examinations, including tests for keratoconjunctivitis sicca (dry eye), were used to study the ocular surface. The tear levels of IL-8 and IFN-gamma in the CF patients were significantly higher than those in controls. The clinical severity of CF correlated significantly with the IL-8 and IFN-gamma levels. We found positive correlation between the tear levels of IFN-gamma and dry eye findings in CF patients. Our results suggest that the inflammatory cytokines IL-8 and IFN-gamma may play key roles in the regulation of ocular surface inflammation and the immunologic reaction in patients with CF. The tear levels of IL-8 and IFN-gamma may be candidate markers for evaluation of the clinical status of CF and eye disease. These findings help to provide a new insight into the pathogenesis of dry eye in patients with CF and provide potential targets for therapy. 相似文献
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Cideciyan AV Aleman TS Swider M Schwartz SB Steinberg JD Brucker AJ Maguire AM Bennett J Stone EM Jacobson SG 《Human molecular genetics》2004,13(5):525-534
Mutations in ABCA4, which encodes a photoreceptor specific ATP-binding cassette transporter (ABCR), cause autosomal recessive forms of human blindness due to retinal degeneration (RD) including Stargardt disease. The exact disease sequence leading to photoreceptor and vision loss in ABCA4-RD is not known. Extrapolation from murine and in vitro studies predicts that two of the earliest pathophysiological features resulting from disturbed ABCR function in man would be slowed kinetics of the retinoid cycle and accelerated deposition of lipofuscin in the retinal pigment epithelium (RPE). To determine the human pathogenetic sequence, we studied surrogate measures of retinoid cycle kinetics, lipofuscin accumulation, and rod and cone photoreceptor and RPE loss in ABCA4-RD patients with a wide spectrum of disease severities. There were different extents of photoreceptor/RPE loss and lipofuscin accumulation in different regions of the retina. Slowing of retinoid cycle kinetics was not present in all patients; when present, it was not homogeneous across the retina; and the extent of slowing correlated well with the degree of degeneration. The orderly relationship between these phenotypic features permitted the development of a model of disease sequence in ABCA4-RD. The model predicted lipofuscin accumulation as a key and early component of the disease expression in man, as in mice. In man, however, abnormal slowing of the rod and cone retinoid cycle occurs at later stages of the disease sequence. Knowledge of the human ABCA4 disease sequence will be critical for defining rates of progression, selecting appropriate patients and retinal locations for future therapy, and choosing appropriate treatment outcomes. 相似文献