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11.
Decreased expression of phospholipase C-beta 2 isozyme in human platelets with impaired function 总被引:4,自引:4,他引:4
Platelets from a patient with a mild inherited bleeding disorder and abnormal platelet aggregation and secretion show reduced generation of inositol 1,4,5-trisphosphate, mobilization of intracellular Ca2+, and phosphorylation of pleckstrin in response to several G protein mediated agonists, suggesting a possible defect at the level of phospholipase C (PLC) activation (see accompanying report). A procedure was developed that allows quantitation of platelet PLC isozymes. After fractionation of platelet extracts by high-performance liquid chromatography, 7 out of 10 known PLC isoforms were detected by immunoblot analysis. The amount of these isoforms in normal platelets decreased in the order PLC- gamma 2 > PLC-beta 2 > PLC-beta 3 > PLC-beta 1 > PLC-gamma 1 > PLC- delta 1 > PLC-beta 4. Compared with normal platelets, platelets from the patient contained approximately one-third the amount of PLC-beta 2, whereas PLC-beta 4 was increased threefold. These results suggest that the impaired platelet function in the patient in response to multiple G protein mediated agonists is attributable to a deficiency of PLC-beta 2. They document for the first time a specific PLC isozyme deficiency in human platelets and provide an unique opportunity to understand the role of different PLC isozymes in normal platelet function. 相似文献
12.
SG Lindquist M Duno M Batbayli A Puschmann H Braendgaard S Mardosiene K Svenstrup LH Pinborg K Vestergaard LE Hjermind J Stokholm BB Andersen P Johannsen JE Nielsen 《Clinical genetics》2013,83(3):279-283
Recently, a hexanucleotide (GGGGCC) repeat expansion in the first intron of C9ORF72 was reported as the cause of chromosome 9p21‐linked frontotemporal dementia‐amyotrophic lateral sclerosis (FTD‐ALS). We here report the prevalence of the expansion in a hospital‐based cohort and associated clinical features indicating a wider clinical spectrum of C9ORF72 disease than previously described. We studied 280 patients previously screened for mutations in genes involved in early onset autosomal dominant inherited dementia disorders. A repeat‐primed polymerase chain reaction amplification assay was used to identify pathogenic GGGGCC expansions. As a potential modifier, confirmed cases were further investigated for abnormal CAG expansions in ATXN2. A pathogenic GGGGCC expansion was identified in a total of 14 probands. Three of these presented with atypical clinical features and were previously diagnosed with clinical olivopontocerebellar degeneration (OPCD), atypical Parkinsonian syndrome (APS) and a corticobasal syndrome (CBS). Further, the pathogenic expansion was identified in six FTD patients, four patients with FTD‐ALS and one ALS patient. All confirmed cases had normal ATXN2 repeat sizes. Our study widens the clinical spectrum of C9ORF72related disease and confirms the hexanucleotide expansion as a prevalent cause of FTD‐ALS disorders. There was no indication of a modifying effect of the ATXN2 gene. 相似文献
13.
Ahmed Z Elmaadawi Peter S Jensen L Eugene Arnold Brooke SG Molina Lily Hechtman Howard B Abikoff Stephen P Hinshaw Jeffrey H Newcorn Laurence Lee Greenhill James M Swanson Cathryn A Galanter 《World Journal of Psychiatry》2015,5(4):412-424
AIM: To determine the prevalence of bipolar disorder (BD) and sub-threshold symptoms in
children with attention deficit hyperactivity disorder (ADHD) through 14 years’
follow-up, when participants were between 21-24 years old.METHODS: First, we examined rates of BD type I and II diagnoses in youth
participating in the NIMH-funded Multimodal Treatment Study of ADHD (MTA). We used the
diagnostic interview schedule for children (DISC), administered to both parents (DISC-P) and
youth (DISCY). We compared the MTA study subjects with ADHD (n = 579) to a
local normative comparison group (LNCG, n = 289) at 4 different assessment
points: 6, 8, 12, and 14 years of follow-ups. To evaluate the bipolar variants, we compared
total symptom counts (TSC) of DSM manic and hypomanic symptoms that were generated by DISC in
ADHD and LNCG subjects. Then we sub-divided the TSC into pathognomonic manic (PM) and
non-specific manic (NSM) symptoms. We compared the PM and NSM in ADHD and LNCG at each
assessment point and over time. We also evaluated the irritability as category A2 manic symptom
in both groups and over time. Finally, we studied the irritability symptom in correlation with
PM and NSM in ADHD and LNCG subjects.RESULTS: DISC-generated BD diagnosis did not differ significantly in rates between ADHD
(1.89%) and LNCG 1.38%). Interestingly, no participant met BD diagnosis more than once in the 4
assessment points in 14 years. However, on the symptom level, ADHD subjects reported
significantly higher mean TSC scores: ADHD 3.0; LNCG 1.7; P < 0.001. ADHD
status was associated with higher mean NSM: ADHD 2.0 vs LNCG 1.1;
P < 0.0001. Also, ADHD subjects had higher PM symptoms than LNCG, with PM
means over all time points of 1.3 ADHD; 0.9 LNCG; P = 0.0001. Examining both
NSM and PM, ADHD status associated with greater NSM than PM. However, Over 14 years, the NSM
symptoms declined and changed to PM over time (df 3, 2523; F = 20.1; P <
0.0001). Finally, Irritability (BD DSM criterion-A2) rates were significantly higher in ADHD
than LNCG (χ2 = 122.2, P < 0.0001), but irritability was
associated more strongly with NSM than PM (df 3, 2538; F = 43.2; P <
0.0001).CONCLUSION: Individuals with ADHD do not appear to be at significantly greater risk for
developing BD, but do show higher rates of BD symptoms, especially NSM. The greater linkage of
irritability to NSM than to PM suggests caution when making BD diagnoses based on irritability
alone as one of 2 (A-level) symptoms for BD diagnosis, particularly in view of its frequent
presentation with other psychopathologies. 相似文献
14.
PurposeTo evaluate the effect of Haishengsu (HSS), a protein extract from Tegillarca granosa, on multidrug-resistance genes mdr1, BCR/ABL and sorcin in transplanted tumors.Material/MethodsMice were inoculated subcutaneously with a drug resistant leukemia cell line K562/ADM. Tumor-bearing animals were divided into control, adriamycin, HSS and combination therapy (adriamycin plus HSS) groups. Flow cytometry was used to detect apoptosis of tumor cells, and RT-PCR was used to evaluate the expression of mdr1, BCR/ABL and sorcin.ResultsThe apoptosis rate in the high (71.8%), medium (72.3%) and low doses HSS group (72.4%) was higher than in control (1.2%, p<0.01), adriamycin (34.4%, p<0.05) or combination therapy group (46.4%, p<0.05). The mean optical density of mdr1, BCR/ABL and sorcin in HSS groups was lower than in control, adriamycin and combination therapy group (p<0.01). The optical density of the three genes in high HSS group was lower than in medium and low HSS group (p<0.01).ConclusionsHaishengsu promotes apoptosis of drug-resistant K562/ADM tumors in mice in a dose-dependent manner. The pro-apoptotic effect of Haishengsu may be related to a reduced expression of multidrug-resistance genes mdr1, BCR/ABL and sorcin. 相似文献
15.
Valerii E. Orel Marina Tselepi Thanos Mitrelias Alexander Rykhalskyi Andriy Romanov Valerii B. Orel Anatoliy Shevchenko Anatoliy Burlaka Sergey Lukin Crispin H.W. Barnes 《Nanomedicine : nanotechnology, biology, and medicine》2018,14(4):1249-1256
Modulation of reactive oxygen and nitrogen species in a tumor could be exploited for nanotherapeutic benefits. We investigate the antitumor effect in Walker-256 carcinosarcoma of magnetic nanodots composed of doxorubicin-loaded Fe3O4 nanoparticles combined with electromagnetic fields. Treatment using the magnetic nanodot with the largest hysteresis loop area (3402 erg/g) had the greatest antitumor effect with the minimum growth factor 0.49 ± 0.02 day–1 (compared to 0.58 ± 0.02 day–1 for conventional doxorubicin). Electron spin resonance spectra of Walker-256 carcinosarcoma treated with the nanodots, indicate an increase of 2.7 times of free iron (that promotes the formation of highly reactive oxygen species), using the nanodot with the largest hysteresis loop area, compared to conventional doxorubicin treatment as well as increases in ubisemiquinone, lactoferrin, NO-FeS-proteins. Hence, we provide evidence that the designed magnetic nanodots can modulate the tumor redox state. We discuss the implications of these results for cancer nanotherapy. 相似文献
16.
MR imaging of the breast 总被引:2,自引:0,他引:2
Orel SG 《Magnetic Resonance Imaging Clinics of North America》2001,9(2):273-88, v
The results of clinical investigation suggest that MR imaging can provide clinically important information that cannot be obtained with conventional imaging methods, and that this modality will, in the future, be an invaluable adjunctive breast imaging tool, just as breast imaging is today. MR imaging as a method to detect, diagnose, and stage breast cancer remains in the investigational stage, but is emerging as perhaps the most promising imaging modality for breast cancer detection. 相似文献
17.
18.
目的研究曲安奈德(TA)辅助玻璃体切割手术在临床的应用价值。方法28例(29只眼)于2004年1月~2004年12月行玻璃体切割术,术中注入已过滤的TA悬浮液0.1ml(40mg/m1),以帮助辨认玻璃体后皮质、视网膜前增殖膜、黄斑前膜、内界膜,9例硅油填充,7例C3FR(15%)填充。手术后17例随访6个月以上,11例随访3至4个月。结果所有的病例,经TA注入后,可明显的改善玻璃体后皮质、视网膜前膜、内界膜的辨认情况。糖尿病视网膜病变术后视力提高占61.5%,伴PVR的视网膜脱离术后视力提高占61.3%,黄斑裂孔4例中3例术后视力提高,4例黄斑前膜术后视力均有提高。所有28例均没有出现高眼压。8例伴PVR的视网膜脱离中6例(占75%)视网膜复位,4例黄斑裂孔均关闭,2例糖尿病黄斑水肿手术后明显减轻。结论经过滤的TA可作为玻璃体切割手术中较好的辅助工具,TA悬浮液是呈白色胶样,可粘附于玻璃体皮质、视网膜前膜或内界膜,帮助分辨玻璃体后皮质、视网膜前膜、内界膜,提高手术效率。没有发现与TA有关的副作用。 相似文献
19.
20.
Mueller PR; Silverman SG; Tung G; Brink JA; Cardenosa G; Saini S; Forman BH; Hahn PF 《Radiology》1989,173(1):278-279
A new tray has been designed for use during procedures involving needles and other sharp objects. The tray includes a foam adhesive pad, marked into 10 sections, into which the sharp objects can be placed point first. After the procedure, the objects can be safely withdrawn by their handles and then discarded. The tray has been used in more than 250 procedures. 相似文献