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991.
Wood JD; MacMillan JC; Harper PS; Lowenstein PR; Jones AL 《Human molecular genetics》1996,5(4):481-487
Huntington's disease (HD) is an inherited neurodegenerative disorder caused
by the expansion of a CAG repeat in a gene coding for a protein of unknown
function. We have raised a polyclonal antibody against a 12 amino acid
peptide (residues 2110-2121 of human huntingtin) which specifically
recognises huntingtin on Western blots of human, rat and mouse brain. We
have characterised huntingtin expression in the mouse. The protein was
detected on Western blots of all mouse tissues examined, with the highest
expression seen in brain. Human, mouse and rat brain were fractionated by
differential centrifugation and discontinuous Percoll gradients. The
fractions were analysed by Western blotting for huntingtin and
synaptophysin (a synaptic vesicle localised protein). In mouse brain,
huntingtin was localised in the soluble S3 fraction; in rat brain it was
localised in the soluble S3 fraction and also in the membrane P2 and P3
fractions; in both normal and HD- affected human brain, huntingtin was
membrane bound with a distribution essentially the same as that of
synaptophysin. These observed differences in the subcellular localisation
of huntingtin between mouse and human brain are important in the context of
mouse models for HD.
相似文献
992.
Brunna E Alves Silmara AL Montalvao Francisco JP Aranha Irene Lorand-Metze Carmino A De Souza Joyce M Annichino-Bizzacchi Erich V De Paula 《Journal of translational medicine》2011,9(1):23
Background
Septic shock is the most feared complication of chemotherapy-induced febrile neutropenia. So far, there are no robust biomarkers that can stratify patients to the risk of sepsis complications. The VEGF-A axis is involved in the control of microvascular permeability and has been involved in the pathogenesis of conditions associated with endothelial barrier disruption such as sepsis. sFlt-1 is a soluble variant of the VEGF-A receptor VEGFR-1 that acts as a decoy receptor down-regulating the effects of VEGF-A. In animal models of sepsis, sFlt-1 was capable to block the barrier-breaking negative effects of VEGF-A and to significantly decrease mortality. In non-neutropenic patients, sFlt-1 has been shown to be a promising biomarker for sepsis severity. 相似文献993.
Effects of cafeteria diet and high fat diet intake on anxiety,learning and memory in adult male rats
Renata Tavares Beschizza Pini Lucas Duarte Manhas Ferreira do Vales Telma Maria Braga Costa 《Nutritional neuroscience》2017,20(7):396-408
Objective: The effects of cafeteria and high fat diets were investigated on animal models of behavior.Methods: Male Wistar rats were treated with Control (C), Cafeteria (CD) and High Fat (FD) diets and tested in the Elevated Plus-Maze (EPM) and Morris Water Maze (MWM) procedures. Body weight, length, abdominal circumference, retroperitoneal and epididymal adipose tissues were recorded. Physical parameters, weight of tissues, EPM, and MWM data were subjected to ANOVA followed by Newman–Keuls test (P?0.05).Results: There were no differences on weight and length parameters between CD and C rats up to 98 days of age. However, abdominal circumferences were higher in CD as compared to C at 35 and 70 days of age, respectively, the 5th and the 7th weeks. FD presented lower measures of weight and abdominal circumference; nevertheless there was an increase on those parameters at the end of the nutritional treatment. Even without an apparent weight gain of CD and FD these animals presented a greater accumulation of retroperitoneal and epididymal adipose tissues. In addition, CD and FD demonstrated behaviors that can suggest lower anxiety. CD showed a better learning performance and FD showed better recall of previous learned information in the memory retention test.Discussion: According to those data it was concluded that hypercaloric diet ingestion was capable of triggering metabolic alterations and possibly lowering anxiety associated to learning or memory improvement on a spatial task. 相似文献
994.
995.
Brito-Junior M Braga NM Rodrigues DC Camilo CC Faria-e-Silva AL 《Journal of applied oral science : revista FOB》2010,18(5):528-532
Objective
The aim of this study was to evaluate the effect of simulated periodontal ligament (SPDL) on custom cast dowel and core removal by ultrasonic vibration.Material and Methods
Thirty-two human maxillary canines were included in resin cylinders with or without SPDL made from polyether impression material. In order to allow tensile testing, the roots included in resin cylinders with SPDL were fixed to cylinders with two stainless steel wires. Post-holes were prepared by standardizing the length at 8 mm and root canal impressions were made with self-cured resin acrylic. Cast dowel and core sets were fabricated and luted with Panavia F resin cement. Half of the samples were submitted to ultrasonic vibration before the tensile test. Data were analyzed statistically by two-way ANOVA and Tukey''s post-hoc tests (p<0.05).Results
The ultrasonic vibration reduced the tensile strength of the samples directly included in resin cylinders. There was no difference between the values, whether or not ultrasonic vibration was used, when the PDL was simulated. However, the presence of SPDL affected the tensile strength values even when no ultrasonic vibration was applied.Conclusion
Simulation of PDL has an effect on both ultrasonic vibration and tensile testing. 相似文献996.
Miranda LA Braga F Fischer RG Sztajnbok FR Figueredo CM Gustafsson A 《Journal of periodontology》2006,77(10):1695-1700
BACKGROUND: The aim of this study was to monitor changes in periodontal inflammation in patients with juvenile idiopathic arthritis (JIA) for 2 years. We investigated the influence of rheumatic disease activity and antirheumatic medication on clinical and immunological parameters of periodontal inflammation in these individuals. METHODS: Two years after a baseline examination, the periodontal and rheumatological conditions of 18 adolescents with JIA and 14 control subjects were described. The clinical periodontal inflammation was monitored by registration of visual plaque, marginal bleeding, probing depth, and clinical attachment loss (AL). Periodontal inflammation was also assessed by analysis of the cytokines interleukin (IL)-1beta and IL-18 and the collagenase matrix metalloproteinase (MMP)-8 by enzyme-linked immunosorbent assay. RESULTS: The erythrocyte sedimentation rate and clinical rheumatological parameters were significantly improved at the 2-year follow-up. The number of sites with plaque decreased, and the number of pockets >/=4 mm increased, whereas bleeding levels and the extension of AL remained unchanged. IL-1beta in gingival crevicular fluid decreased significantly in the JIA group after 2 years. No differences were observed for IL-1beta, MMP-8, or IL-18 levels between groups after 2 years. CONCLUSION: Two years after the baseline examination, no clinical or laboratory differences in periodontal inflammation could be found between JIA patients and control subjects. 相似文献
997.
A modification of a high pressure liquid chromatographic (HPLC) procedure is described that enables the complete separation and quantitation of the A gamma T, A gamma I, and G gamma chains in human fetal hemoglobin. The method, which is fast and accurate, requires 5 to 2000 micrograms Hb F. The purity of the Hb F is not essential and admixture of up to 70% adult Hb does not interfere with the determination. The method has been applied to the Hb F of 64 Black SS patients and 7 persons with the Hb S-HPFH (G gamma A gamma type) conditions. (A) Both "adult" G gamma to A gamma (2:3) and "newborn" G gamma to A gamma (3:2) ratios were observed in adult SS patients, 8 yr and older. Only 12% of the SS patients had the "newborn" ratio. This high G gamma to A gamma ratio may be due to a modification of the genetic switch mechanism that regulates the change of this ratio after birth. (B) Intermediate G gamma to A gamma ratios were only found in young SS patients, 5 yr of age or less. The results suggest a delayed switch of the newborn leads to adult ratio in sickle cell anemia. (C) The A gamma T chain was present in only 6% of all SS patients. One patient is homozygous for this variant chain. (D) Three of the 7 subjects with Hb S-HPFH were positive for the A gamma T chain. Its percentage was low, which suggests that the A gamma T chain gene is in trans of the HPFH determinant. (E) Quantitation of the three gamma chain types is also possible in the Hb F from Hb S heterozygotes with (nearly) normal Hb F levels. Such an analysis is useful for an evaluation of genetic conditions involving variations in the production of (different types of) Hb F. 相似文献
998.
Human babesiosis, a parasitic disease transmitted by the tick, Ixodes dammini, was confined previously to limited areas of the northeastern United States. It is a rare but potentially life-threatening complication of transfusion. Red cells and platelets prepared from asymptomatic donors have been implicated in transfusion-transmitted cases. More cases of babesiosis are being reported as the range of the vector expands in the United States. Blood donors from an endemic area were tested for antibody to Babesia microti during the summer. Only 3.7 percent of the 779 donors were seropositive, compared with 4.7 percent (p greater than 0.05) of donors from a nonendemic area. An epidemiologic survey of seropositive and matched seronegative controls demonstrated no significant differences that would assist in screening donors. 相似文献
999.
S. M. Abutarbush A. La Rocca K. Wernike M. Beer K. AL Zuraikat O. M. Al Sheyab A. Q. Talafha F. Steinbach 《Transboundary and Emerging Diseases》2017,64(4):1095-1099
Schmallenberg virus (SBV)‐like clinical cases of abortions in northern Jordan in early 2013, together with the emergence of SBV in Europe in 2011, its rapid spread within the following years and the detection of this virus in Turkey, raised questions about the distribution of SBV or related orthobunyaviruses. To evaluate the occurrence of SBV or related members of the Simbu serogroup of orthobunyaviruses in Jordan, bulk milk (cattle) and serum samples (cattle, sheep and goat) collected in northern Jordan in 2013 were first tested by commercially available SBV antibody ELISAs. Indeed, 3 of 47 bulk milk samples and 57 of 115 serum samples provided positive results, but SBV specificity of the ELISA results could not be confirmed by virus neutralization assays. Instead, subsequent cross‐neutralization tests were able to further investigate the specificity of these antibodies. Here, a significant inhibition of Aino virus was observed. Thus, the causative agent was most likely a Simbu serogroup virus closely related to Aino virus. Consequently, these results confirm that members of this group of virus are not only present in Europe, Africa or Australia, but also in the Middle East. 相似文献
1000.
Radial Bending Breaking Resistance Derived by Densitometric Evaluation Predicts Femoral Neck Fracture 总被引:1,自引:0,他引:1
D. Gatti E. Sartori V. Braga F. Corallo M. Rossini S. Adami 《Osteoporosis international》2001,12(10):864-869
Bone mineral density (BMD) measurement by hip dual-energy X-ray absorptiometry (DXA) is considered the best predictor of
osteoporotic fracture risk. BMD takes into account only in part the bone cross-sectional area that is an important determinant
of both bone compression strength and of bending breaking resistance. From DXA measurements of proximal radius (Osteoplan,
NIM, Verona, Italy) we obtained the projected outer diameter (D) and the mean diameter of the medulla (d), by an algorithm based on the assumption of a constant cortical volumetric density of 1050 g/cm3. The algorithm was validated by the good correlation found (r= 0.8) between calculated d and that actually measured by peripheral quantitative tomography (pQCT; XCT 960, Stratec, Unitrem, Italy) at the same radial
site. The D and d values were used to calculate a bending breaking resistance index (BBRI) that is a component of the cross-sectional moment
of inertia. The BBRI measured in 5460 women aged 35–89 years, was stable up to the age of 65–70 years and rapidly declined
thereafter by 0.7% per year. This profile appears to be due to the fact that the increase in medullary area is compensated
in terms of mechanical resistance by enlargement of cross-sectional area. In 68 women with either previous femoral neck (n= 41) or pertrochanteric fracture (n= 27) DXA measurements at proximal and ultradistal radius, lumbar spine and femoral neck were obtained together with the evaluation
of proximal radius BBRI. The diagnostic accuracy of BBRI was somewhat comparable to that of spine and femoral neck BMD and
significantly superior to that of ultradistal and proximal radius BMD, from which it was derived. Despite the obvious limitation
of the cross-sectional nature of this study, our results indicate that a simple re-elaboration of the data obtained by peripheral
radial densitometry may achieve diagnostic accuracy for hip fracture risk assessment only marginally lower than that of the
direct measure of the BMD of the femoral neck. They also give additional support to the view that bone geometry, particularly
for compact skeletal segments, is a determinant of its strength at least as important as bone density.
Received: 25 July 2000 / Accepted: 9 April 2001 相似文献