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101.
Martini L Fini M Giavaresi G Torricelli P de Pretto M Rimondini L Giardino R 《Artificial cells, blood substitutes, and immobilization biotechnology》2003,31(4):449-466
Over the past decade extracorporeal shock-wave therapy (ESWT) has been increasingly applied to orthopaedic and musculoskeletal pathologies, the aim of this study was to assess how the energy density of the shock waves and the number of impulses affect viability, differentiation and synthetic activity of osteoblasts. Primary sheep osteoblasts cultures were treated with ESWT with an electro-hydraulic shock wave generator by selecting three different energy levels (14-21-28 kV corresponding at 0.15-0.31-0.40 mJ/mm2) and two different total numbers of impulses (500, 1000) for each level. At the end of treatment, cell counts and viability were recorded. Cells were then cultivated for 48 hours starting from a concentration of 1 x 10(4) cells/ml. The biological activity and viability were evaluated at 24 and 48 hours after treatment. No cytodestructive effects were observed in Group A, while a cytodestructive effect of ESWT was seen in cultures receiving the highest energy treatments. The different shock wave treatment induced differences in MTT assays after 24 and 48 hours, in particular the highest level showed a detrimental effect on cell respiration at both experimental times as compared to the Control Group and the protein metabolism was generally depressed by ESWT with impulses at the highest energy level. After 24 hours such effect further increased with the growing number of impulses. The lowest energy level appeared to significantly improve the metabolic parameter in primary cell cultures as compared to controls when 500 impulses were selected. The current study has demonstrated that one of the most important aspects to be considered is not the total number of impulses used but the energy level of the shock waves, thus confirming that ESWT has a dose-dependent effect on cells. 相似文献
102.
Pardono E van Bever Y van den Ende J Havrenne PC Iughetti P Maestrelli SR Costa F O Richieri-Costa A Frota-Pessoa O Otto PA 《American journal of medical genetics. Part A》2003,(3):223-235
Here we present the results of a study performed on 59 patients affected by Waardenburg syndrome (WS), 30 with the I variant, 21 having the type II, and 8 of them being isolated cases without telecanthus. These patients belong to 37 families; the main contributions and conclusions are based on the detailed study of 25 of these families, examined using standard procedures. All patients were examined as to the presence of eight cardinal signs important for the diagnosis of the condition; from each patient, from many of his/her normal relatives, and from a control sample of 300 normal individuals stratified by age and sex, 23 different craniofacial measurements were obtained. We also estimated, using our own data as well those collected from the literature, the frequencies of the cardinal signs, based on a total sample of 461 affected individuals with WSI and 121 with WSII. In order to originate discriminant functions to separate individuals affected by one of the two variants, both metric (from craniofacial measurements) as well as categoric data (based on the frequencies of the cardinal signs or symptoms) were used. Discriminant analysis based on the frequency of the eight cardinal signs can improve the separation of WSI patients without telecanthus from those presenting the variant II. We present also a Table with the conditional probabilities favoring the diagnosis of WSI for suspect subjects without telecanthus and any combination of the other seven signs/symptoms. The discriminant function based on the four ocular measurements (inner and outer intercanthal, interpupillary, and inferior lacrymal distances), on the other side, perfectly classifies patients affected by one of the variants of WS, the same taking place when the average values of the W index of all affected individuals per family are used. The discriminant function based solely in the individual W index values of patients correctly classifies 93% of WSII subjects, but only 60% of the patients with the I variant of WS. 相似文献
103.
Gontijo AM Marcondes JP Elias FN de Oliveira ML de Lima RO Salvadori DM de Camargo JL 《Environmental and molecular mutagenesis》2002,40(3):190-199
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells. 相似文献
104.
Duranti R Sanna A Romagnoli I Nerini M Gigliotti F Ambrosino N Scano G 《Pflügers Archiv : European journal of physiology》2004,448(2):222-230
We hypothesized that walking at increased speed or increasing gradient might have different effects on chest wall kinematics and respiratory muscle power components, and contribute differently to respiratory effort sensation. We measured the volumes of chest wall compartments by optoelectronic plethysmography, esophageal, gastric and transdiaphragmatic (P
di) pressures, and the sensation of the respiratory effort by a Borg scale in five normal subjects walking both at ascending gradient with constant speed (AG) and at ascending speed with constant gradient (AS). Chest wall kinematics, evaluated by displacement of chest wall compartments, did not show any significant difference between AS and AG. Muscle power, calculated as the product of mean flow and mean pressure, increased similarly, but its partitioning into pressure and velocity of shortening differed in the two modes. A greater increase in the pressure developed by the abdominal muscles (P
abm) (4.06-fold), and in the velocity of shortening of both rib cage inspiratory muscles (v
rcm,i) (2.01-fold) and the diaphragm (v
di) (1.90-fold) was associated with a lower increase in the pressure developed by the rib cage inspiratory muscles (P
rcm,i) (1.24-fold) and P
di (0.99-fold) with AG. Instead, with AS, a lower increase in P
abm (2.12-fold), v
rcm,i (1.66-fold) and v
di (1.54-fold) was associated with a greater increase in P
rcm,i (1.56-fold) and P
di (1.97-fold). A combination of P
abm and v
di during AG (Wald 2=23.19, P<0.0000), with the addition of P
rcm,i during AS (Wald 2=29.46, P<0.0000), was the best predictor of Borg score. In conclusion, the general strategy adopted by respiratory centers during different walking modes does not differ in terms of ventilation, chest wall kinematics, and respiratory muscle power production, whereas it does in terms of partitioning of power into pressure and velocity of shortening, and respiratory muscle contribution to respiratory effort sensation. Combinations of different patterns of flow and pressure generation made the respiratory effort sensation similar during AS and AG modes. 相似文献
105.
Scali C Prosperi C Bracco L Piccini C Baronti R Ginestroni A Sorbi S Pepeu G Casamenti F 《Neurobiology of aging》2002,23(4):523-530
To evaluate whether inflammation-like mechanisms present in the brain of Alzheimer's disease (AD) patients are reflected in the periphery, the expression of CD11b in peripheral blood neutrophils and the expression and activity of inflammatory markers in cultured skin fibroblasts were examined. We found significantly higher levels of CD11b in neutrophils from sporadic AD patients than in controls and this elevation was positively correlated with disease severity and progression rate of mental decline. Cultured skin fibroblasts from familial (FAD) and sporadic AD patients and from controls were immunopositive for both isoforms of cyclooxygenase with no differences between groups. In unstimulated culture, the production of prostaglandin-E2 in the medium was significantly higher in fibroblasts from sporadic AD and FAD patients than in controls, and this elevation was reverted by the addition of 25 microM of ibuprofen. Our findings provide further evidence of the presence of inflammatory and immuno-related markers in the periphery of AD patients and support those studies indicating the beneficial effects of anti-inflammatory therapy in AD. 相似文献
106.
Dina Ruano António Macedo Maria Jo?o Soares José Valente Maria Helena Azevedo Carlos Pato Mara Helena Hutz Clarissa S Gama Maria Inês Lobato Paulo Belmonte-de-Abreu Peter Heutink Joana Almeida Palha 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(5):642-646
Several observations point to the involvement of disturbed lipid biology in schizophrenia. Reduced response to niacin flushing test, which involves vasodilatation induced by prostaglandin D2 (PGD2), is among the evidences, together with decreased CSF levels of lipocalin-type prostaglandin D2 synthase (PTGDS), the enzyme responsible for the synthesis of PGD2 in the brain. Since PTGDS is also a carrier for lipophilic molecules such as retinoids and thyroid hormones, altered PTGDS levels might influence both PGD2-mediated signaling, and vitamin A and thyroid hormone availability. To test whether genetic variants of PTGDS are involved in the etiology of schizophrenia, we searched for variants in the coding and regulatory regions of the gene. We identified four previously described polymorphisms. Using two case-control samples from Portugal and Brazil, none of the polymorphisms tested was associated with the disease. In addition, no transmission distortion was observed in an independent parents-offspring sample from the Azorean Islands. Our data do not support the involvement of the PTGDS gene in the etiology of schizophrenia. 相似文献
107.
Facilitation at the frog neuromuscular junction during and after repetitive stimulation 总被引:8,自引:0,他引:8
M. Braun R. F. Schmidt M. Zimmermann 《Pflügers Archiv : European journal of physiology》1966,287(1):41-55
Summary 1. E.p.p.s and min.e.p.p.s were recorded intracellularly from Mg-blocked nerve muscle preparations (M. sartorius and M. cutaneous pectoris) of summer and winter frogs in vitro.2. Prolonged repetitive stimulation at frequencies above 5/sec induced synaptic facilitation (measured as e.p.p. increase) which continued to increase throughout the longest periods of stimulation tested (40 sec at 20/sec). For a given number of stimuli the facilitation was the greater the higher the frequency of stimulation.3. Increasing the release of ACh per impulse by reducing the Mg-concentration of the bathing solution caused a levelling off and even a depression of the e.p.p.s in the course of tetanic stimulation, i.e. the pattern of the e.p.p. response shifted towards that found in curarized preparations.4. After stimulation the e.p.p.s remained enlarged for periods from 100 to several hundreds of msec, depending on the number and frequency of the conditioning volleys. At frequencies below 100/sec the frequency of stimulation significantly influenced the amount and duration of the e.p.p. facilitation whereas at frequencies above 100/sec the duration of the e.p.p. facilitation was mainly determined by the number of conditioning volleys.5. After stimulation the frequency of the spontaneous min.e.p.p.s was increased. This increase decayed to the control level with a time course similar to that of the e.p.p. facilitation. The possibility is discussed that these parallel changes of e.p.p. amplitude and min.e.p.p. frequency are probably due to a mobilization of transmitter from its presynaptic stores to the release sites.
With 6 Figures in the Text
This work was supported by the Deutsche Forschungsgemeinschaft. 相似文献
Zusammenfassung 1. An Mg-blockierten Nerv-Muskel-Präparaten in vitro (M. sartorius und M. cutaneous pectoris) von Sommer- und Winterfröschen wurden intracellulär e.p.p. und min.e.p.p. gemessen.2. Lange tetanische Reizung mit Frequenzen von mehr als 5 Hz verursacht synaptische Bahnung (gemessen als e.p.p.-Vergrößerung). Diese Bahnung nimmt auch am Ende des längsten untersuchten Tetanus (40 sec bei 20 Hz) noch zu. Für eine gegebene Zahl von Reizen steigt die Bahnung mit der Reizfrequenz.3. Bei Vergrößerung der pro Impuls freigesetzten Menge ACh durch eine Reduktion der Mg-Konzentration der Badelösung erreicht die e.p.p. Amplitude im Verlauf des Tetanus ein Plateau oder beginnt sogar abzunehmen, d.h. die e.p.p. verhalten sich mehr wie in curarisierten Präparaten.4. Nach Reizung bleibt das e.p.p. gebahnt. Je nach Anzahl und Frequenz der Reize dauert die Bahnung hundert bis einige hundert Millisekunden an. Bei Reizfrequenzen von weniger als 100 Hz beeinflußt die Frequenz sowohl die Dauer als auch das Ausmaß der Potenzierung beträchtlich, während bei Frequenzen von mehr als 100 Hz die Dauer hauptsächlich durch die Zahl der Reize bestimmt wird.5. Nach Reizung ist die Frequenz der spontanen min.e.p.p. erhöht. Mit einem Zeitverlauf ähnlich dem der e.p.p.-Potenzierung kehrt die Frequenz der min.e.p.p. wieder zum Ausgangswert zurück. Diese parallelen Veränderungen der e.p.p. Amplitude und der min.e.p.p. Häufigkeit sind wahrscheinlich durch eine vermehrte Bereitstellung (Mobilisation) von Überträgersubstanz am synaptischen Spalt aus den präsynaptischen Speichern verursacht.
With 6 Figures in the Text
This work was supported by the Deutsche Forschungsgemeinschaft. 相似文献
108.
Ferrand PE Fujimoto T Chennathukuzhi V Parry S Macones GA Sammel M Kuivaniemi H Romero R Strauss JF 《Molecular human reproduction》2002,8(11):1031-1034
Infection is believed to be a leading cause of preterm premature rupture of membranes (PPROM). The bacterial cell wall component, lipopolysaccharide (LPS), is thought to initiate tissue responses leading to PPROM in the setting of Gram negative infection. LPS is recognized by the innate immune system, including the proteins encoded by the CARD15 and TLR4 genes. A recently described mutation (2936insC) in CARD15 and a polymorphism in TLR4 896 A>G impair responses to LPS. The objective of this study was to determine if African Americans, who have a higher incidence of PPROM than Caucasians, have different frequencies of the mutant CARD15 allele and the TLR4 hyporesponsive variant, and if risk of PPROM is influenced by fetal carriage of these alleles. The allele frequencies for the CARD15 mutation and the TLR4 896G variant in African Americans were similar to those reported for Caucasians. There was no association between the TLR4 alleles examined and PPROM. However, the CARD15 mutation was only detected in controls and not in PPROM cases. We conclude that the CARD15 mutation and hyporesponsive TLR4 allele do not contribute to ethnic variation in the incidence of PPROM. 相似文献
109.
Antonella Cianferoni Elio Novembre Neri Pucci Enrico Lombardi Roberto Bernardini Alberto Vierucci 《Annals of allergy, asthma & immunology》2004,92(4):464-468
BACKGROUND: Little is known about the frequency of and the features associated with recurrent anaphylaxis in pediatric populations. During 1994 to 1996, we enrolled 76 children affected by anaphylaxis in a prospective study to analyze their clinical and allergic features. OBJECTIVE: To undertake a follow-up study of these children to ascertain how many experienced a recurrence of anaphylaxis. METHODS: After a mean interval of 7 years, a pediatric allergist conducted a telephone interview of patients who had been enrolled in our 1994-1996 study. RESULTS: A telephone interview was successfully completed in 46 (61%) of the 76 patients who had been enrolled in our 1994-1996 study. Of these 46 patients, 14 (30%) had experienced a recurrence of anaphylaxis. Children with atopic dermatitis either during 1994 to 1996 (64% vs 34%; P = .04) or at the time of the current study (43% vs 16%; P = .03) and those with urticaria-angioedema at the time of the current study (93% vs 31%; P = .0002) were found to be at a significantly higher risk for recurrent anaphylaxis. Furthermore, those children who were sensitive to at least 1 food allergen during 1994 to 1996 were more likely to have experienced a recurrence of anaphylaxis (93% vs 56%; P < .04). CONCLUSIONS: This study suggests that patients may have a greater risk of recurrence of anaphylaxis if they have atopic dermatitis, urticaria-angioedema, or at least 1 positive result of skin prick tests to food allergens. 相似文献
110.