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排序方式: 共有1166条查询结果,搜索用时 15 毫秒
81.
Mats Eriksson Gunnar Strandberg Miklós Lipcsey 《Scandinavian journal of clinical and laboratory investigation》2016,76(8):597-600
Background: Intraosseous (IO) access can be established faster than a venous or arterial access when there is an urgent need for rapid initiation of treatment. The access can also be used to draw marrow samples. The aim of the present study was to evaluate the potential use of IO samples for enzyme determinations using a porcine model.Materials and methods: Bilateral tibial intraosseous cannulae and an arterial catheter were used for blood sampling from five healthy anesthetized pigs. Samples were collected at baseline and thereafter hourly for 6?h and analyzed for alanine aminotransferase, alkaline phosphatase, aspartate aminotransferase, creatinine kinase, gamma-glutamyl transferase and lactate dehydrogenase.Results: Creatinine kinase, lactate dehydrogenase and alkaline phosphatase levels decreased over time. The differences between IO and arterial sampling were limited for all studied markers.Conclusion: The correlation between marrow and blood analysis for liver function tests and CK is sufficiently accurate in an emergency situation. 相似文献
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84.
Merkel OM Urbanics R Bedocs P Rozsnyay Z Rosivall L Toth M Kissel T Szebeni J 《Biomaterials》2011,32(21):4936-4942
Complement activation by polymeric gene and drug delivery systems has been overlooked in the past. As more reports appear in the literature concerning immunogenicity of polymers and their impact on gene expression patterns, it is important to address possible immune side effects of polymers, namely complement activation. Therefore, in this study the activity of low and high molecular weight poly(ethylene imine) and two PEGylated derivatives to induce complement activation were investigated in human serum. These in vitro results revealed that PEI 25 kDa caused significant and concentration dependent complement activation, whereas none of the other polymers induced such effects at their IC(50) concentrations determined by MTT-assays. To verify these in vitro results, additionally, studies were carried out in a swine model after intravenous administration, showing complement activation-related pseudoallergy (CARPA), reflected in symptoms of transient cardiopulmonary distress. Injections of PEI 25 kDa or PEI(25k)-PEG(2k)(10) at a dose of 0.05 and 0.1 mg/kg caused strong reactivity, while PEI 5 kDa and with PEI(25k)-PEG(20k)(1) were also reactogenic at 0.1 mg/kg. It was found that PEI 25 kDa caused both self- and cross-tolerance, whereas the PEG-PEIs were neither self- nor cross-reactively tachyphylactic. As a result of this study, it was shown that PEGylation of polycations with PEG of 20 kDa or higher molecular weight may be favorable. However, potential safety concerns in the development of PEI-based polymeric carriers for drugs and nucleic acids and their translation from bench to bedside need to be taken into consideration for human application. 相似文献
85.
Tot T Gere M Pekár G Tarján M Hofmeyer S Hellberg D Lindquist D Chen TH Yen AM Chiu SY Tabár L 《Human pathology》2011,42(11):1761-1769
The prognostic information implied in subgross morphologic parameters such as lesion distribution (unifocal, multifocal, or diffuse) and disease extent in breast cancer has remained largely unexplored in the literature. We aimed to test whether these parameters influence survival in breast carcinoma. The parameters were assessed in a series of 574 cases, all documented in large-format histology sections. We used Cox proportional hazards regression accompanied by Kaplan-Meyer survival curves, with P < .05 regarded as significant. The invasive component was unifocal in 62% (311/499), multifocal in 24% (122/499), and diffuse in 5% (26/499) of the cases. Combining the in situ and invasive tumor components resulted in 48% (274/574) unifocal, 25% (141/574) multifocal, and 20% (117/574) diffuse tumors. Sixty percent (347/574) of the tumors were categorized as having limited extent (occupying an area <40 mm in largest dimension) and 29% (164/574) as extensive. Highly significant (P < .0001) differences were observed in 10-year disease-specific cumulative survival among the cases with unifocal, multifocal, and diffuse invasive (89.6%, 76.0%, and 63.6%, respectively) and combined (92.3%, 82.3%, and 75.7%, respectively) lesion distribution. Patients with extensive tumors exhibited a significantly lower cumulative survival (P < .0001) compared with those with limited extent (91.6% and 75.5%) and a statistically significantly 1.89-fold (95% confidence interval, 1.07-3.37; P = .03) risk for breast cancer death after controlling for tumor attributes, type of surgery, and adjuvant therapy. The hazard ratio for breast cancer death for mutifocal and/or diffuse tumors versus unifocal ones was 1.96 (95%; 1.11-3.48; P = .02) after controlling for the same factors. Lesion distribution and disease extent represent important independent survival-related prognostic parameters in breast carcinoma. 相似文献
86.
Kovács ZI Palkovits M 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2011,208(1):51-60
This study is meant to combine traditional aspects of tracer microinjections using bone landmarks like bregma and lambda with
novel procedures in which specific parts of the brain can serve as reference points. For telencephalic and diencephalic injections,
the brain surface, the interhemispheric groove and the straight sinus can be used as absolute zero points for dorso-ventral,
medio-lateral and rostro-caudal coordinates, respectively. In case of brainstem targets, the surface of the rhomboid fossa,
the posterior spinal artery and the obex could serve as reference points along the above-mentioned coordinates. The application
of high-precision stereotaxic measurements based on intracranial landmarks and sophisticated surgical procedures can yield
well-targeted, small and well circumscribed injection sites that make possible the mapping of discrete nuclear subdivisions
or delicate nuclei in the brain. 相似文献
87.
Tomas Kasparek Radovan Prikryl Daniel Schwarz Hana Kucerova Radek Marecek Michal Mikl Jiri Vanicek Eva Ceskova 《Progress in neuro-psychopharmacology & biological psychiatry》2009
Schizophrenia is a condition with a highly variable course that is hard to predict. The aim of the present study was to investigate if local gray matter volume (GMV) can differentiate poor (PF) and good (GF) functioning patients using voxel-wise analysis in a group of first-episode schizophrenia subjects (FES). 相似文献
88.
Kaspárek T Prikryl R Mikl M Schwarz D Cesková E Krupa P 《Progress in neuro-psychopharmacology & biological psychiatry》2007,31(1):151-157
INTRODUCTION: Changes of brain morphology are now considered as a part of the pathology of schizophrenia. Voxel-based morphometry may be used to study regional changes of the grey matter in the whole brain. It is advantageous to study first-episode patients to prevent the influence of many possible biasing factors when trying to identify primary pathological processes underlying the manifestation of the illness. OBJECTIVE: To investigate regional grey matter changes in the first-episode schizophrenia patients. METHODS: Optimized voxel-based morphometry was used to detect changes in grey matter volume in 22 patients with first-episode schizophrenia compared with 18 healthy volunteers of comparable age, gender and handedness. RESULTS: The first-episode schizophrenia group had significantly reduced grey matter volume in the prefrontal cortex (inferior and middle prefrontal gyrus, cingulate gyrus). We identified no differences in the temporal cortex. CONCLUSION: Our data support the theoretical assumption that prefrontal dysfunction underlines the primary pathology and clinical manifestation of schizophrenia. We are inclined to explain the differences in the pattern of morphological changes reported in other first-episode studies--especially the lack of changes in the temporal cortex--by heterogeneity of schizophrenia, potential progression and antipsychotic medication effect. 相似文献
89.
Nagy B Csongrádi E Bhattoa HP Balogh I Blaskó G Paragh G Kappelmayer J Káplár M 《Thrombosis and haemostasis》2007,98(1):186-191
Increased levels of soluble P-selectin (sP-selectin) have been shown in a number of different disorders, e.g. diabetes mellitus (DM) and cardiovascular disease (CVD). Several studies have attempted to demonstrate the association of the most intensively examined variant of P-selectin gene polymorphism (Thr715Pro) with sP-selectin levels in healthy subjects and in CVD, but contradictory data have been reported. To clarify the effect of Pro715 allele on the sP-selectin levels in type 2 DM, we analysed this polymorphism in diabetic patients and compared these data with sP-selectin levels. Type 2 DM patients (n = 119), 48 BMImatched non diabetic individuals - consisting mostly of overweight subjects - and 57 healthy volunteers were included in the study. TheThr715Pro polymorphism was analysed by PCR-RFLP, while sP-selectin levels were measured by ELISA. Significantly elevated sP-selectin levels were found in both DM and in overweight subjects compared to healthy controls. We confirmed previous reports that in healthy Pro715 allele carriers lower sPselectin levels could be measured; however, this difference was only significant in case of lean subjects. No significant difference was detected in sP-selectin level among DM and overweight individuals according to this genotype. However, significant difference was observed in sP-selectin levels in older DM patients compared to younger ones, but these levels were not accounted for by the Thr715Pro polymorphism. We suggest that in type 2 DM individuals, the significantly elevated sP-selectin levels are not due to the Thr715Pro P-selectin gene polymorphism. 相似文献
90.
Tõke J Czirják G Patócs A Enyedi B Gergics P Csákváry V Enyedi P Tóth M 《Clinical endocrinology》2007,67(3):385-392
INTRODUCTION: Neonatal severe hyperparathyroidism (NSHPT) is induced by inactivating mutations of human calcium-sensing receptor (CaSR). Only three heterozygous de novo inactivating mutations of CaSR causing NSHPT have been described. We report the case of a now 11-year-old boy with NSHPT and we characterize a novel inactivating mutation along with the results of some functional analyses. PATIENT AND METHODS: As a neonate the patient presented the clinical syndrome of NSHPT. At 6 years of age persisting hypercalcaemia without clinical symptoms was documented, and the patient remained completely symptom free without parathyroid surgery until his present age of 11 years. The entire coding region of the CaSR gene of the patient and his family members was sequenced. Functional investigation was performed in HEK-293 cells, transiently transfected with wild type and mutant CaSR plasmid constructs. RESULTS: Sequence analysis revealed a novel de novo heterozygous mutation at codon 551 (AGG-->AAG), predicting a change of arginine to lysine (R551K) and a known heterozygous polymorphism (A986S) on the same allele, which was inherited from the father. We demonstrated that the novel R551K mutation significantly reduced the calcium sensitivity of CaSR (EC50: from 3.38 +/- 0.62-6.10 +/- 0.83 mmol/l), which was not alleviated by the simultaneous presence of A986S polymorphism. CONCLUSIONS: We present the fourth NSHPT case induced by a novel de novo heterozygous inactivating mutation (R551K) of the CaSR gene. The disease gradually reverted to a symptomless, benign condition resembling familial hypocalciuric hypercalcaemia without any surgical intervention. 相似文献