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排序方式: 共有957条查询结果,搜索用时 31 毫秒
31.
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
32.
Five groups (n = 11) of 250-g female rats were oophorectomized and immediately thereafter received daily sc injections of estradiol benzoate (EB; 0.05, 0.5, 5.0, and 50.0 micrograms) or vehicle for 28 days. A sixth group underwent sham operation and received injections of vehicle. Somatomedin-C (SmC) concentrations were determined before EB administration. After 4 weeks of EB treatment, the GH response to human GH-releasing factor (1-44) (GRF; 5 micrograms/kg, iv) was determined under pentobarbital anesthesia in seven animals from each group. Serum PRL, LH, and estradiol and plasma SmC concentrations were also measured. The GH secretory response to GRF (delta GH) was greatest in castrated animals receiving vehicle (P less than 0.05) and was significantly blunted in animals receiving 5.0 and 50.0 micrograms EB (P less than 0.05) compared to that in sham-operated animals. A significant negative correlation was observed between delta GH and serum PRL concentrations (r = -0.53; P less than 0.0001). SmC concentrations after treatment were significantly lower in animals receiving 5.0 and 50.0 micrograms EB (P less than 0.01), than in sham-operated animals and were elevated compared to those in sham-operated controls in the group receiving the lowest dose of EB (0.05 microgram; P less than 0.01). Posttreatment SmC levels correlated positively with delta GH (r = 0.58; P less than 0.001) and negatively with serum estradiol concentrations (r = -0.47; P less than 0.01). Pituitary glands from the remaining animals in each group (n = 4) were weighed and assayed for GH, PRL, and LH content. Pituitary PRL content increased with increasing doses of EB replacement and correlated strongly (r = 0.82; P less than 0.0001) with pituitary weight. In the castrated adult female rat, high doses of estrogen inhibited the GH secretory response to GRF in vivo and decreased SmC concentrations. Low dose estrogen increased SmC concentrations, although the GH secretary response to GRF in this group was similar to that in sham-operated rats. The latter observation suggests that the rise in SmC levels associated with low dose estrogen may not be mediated through a change in GH secretion. 相似文献
33.
C. Tobon-Gomez N. Duchateau R. Sebastian S. Marchesseau O. Camara E. Donal M. De Craene A. Pashaei J. Relan M. Steghofer P. Lamata H. Delingette S. Duckett M. Garreau A. Hernandez K. S. Rhode M. Sermesant N. Ayache C. Leclercq R. Razavi N. P. Smith A. F. Frangi 《Medical & biological engineering & computing》2013,51(11):1235-1250
34.
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
35.
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
36.
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
37.
38.
M. Vella E. Nellist L. Cardozo H. Mastoroudes I. Giarenis J. Duckett 《International urogynecology journal》2013,24(11):1947-1951
Introduction and hypothesis
Pelvic floor muscle training (PFMT) is the recommended first-line treatment for women with urinary incontinence (UI). Success rates are variable and dependent on a number of factors. The development of an incontinence treatment motivation questionnaire (ITMQ) provides us with a tool to assess patient self-motivation with respect to PFMT and UI. The aim of this study was to determine the effect of women’s self-motivation to perform PFMT on outcome.Methods
Women with stress predominant UI completed an ITMQ and a 24-h pad test and then underwent a 12-week course of supervised PFMT. At the end of their treatment they completed a patient global impression of improvement questionnaire (PGI-I) and a second 24-h pad test. The PGI-I scores and the difference in pad test weight correlated with the ITMQ according to Spearman’s correlation coefficient.Results
Sixty-five women were recruited. Thirty-two (49 %) patients perceived themselves as having improved, 28 women (43 %) did not experience any change in symptoms and 5 women (8 %) felt that their symptoms deteriorated following treatment. When correlating the PGI-I with the ITMQ, 3 of the 5 domains: MQS1 (positive attitude for treatment; p?=?0.003), MQS3 (frustration of living with incontinence; p?=?0.002) and MQS4 (desire for treatment; p?=?0.002) correlated significantly with outcome. Desire for treatment was the only domain to correlate with change in pad weight (p?=?0.001).Conclusion
Self-motivation is essential in order to determine improved success rates with PFMT. 相似文献39.
Introduction and hypothesis
Pain after suburethral sling insertion is an uncommon, but troublesome complication of continence surgery; in some cases it can cause significant distress and disability. It is often not recognised, poorly diagnosed and treated by gynaecologists and urologists unfamiliar with the condition.Methods
A literature review was performed and the current evidence on pain after suburethral sling insertion reviewed.Results
The tension-free vaginal tape–obturator (TVT-O) procedure is associated with an increased incidence of early groin pain, but this often resolves with expectant management. Chronic pain may be difficult to treat. The injection of local anaesthetic and steroid solutions may provide relief in some patients. Cognitive behavioural therapy has a place in treatment. In resistant cases, surgical excision may be needed. Retropubic slings can be removed laparoscopically or by open exploration of the Cave of Retzius. Obturator tapes may require groin exploration.Conclusions
Sling removal may result in recurrent incontinence and further tissue and nerve damage. It does not always cure pain and may exacerbate the problem. 相似文献40.
Sharif Ismail Jonathan Duckett Diaa Rizk Olanrewaju Sorinola Dorothy Kammerer-Doak Oscar Contreras-Ortiz Hazem Al-Mandeel Kamil Svabik Mitesh Parekh Christian Phillips 《International urogynecology journal》2016,27(11):1619-1632