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61.
No increased human herpesvirus 8 seroprevalence in patients with HIV-associated non-Hodgkin's lymphoma 总被引:1,自引:0,他引:1
Gérard L Agbalika F Sheldon J Maillard A Schulz TF Oksenhendler E 《Journal of acquired immune deficiency syndromes (1999)》2001,26(2):182-184
Human herpesvirus 8 (HHV-8) is closely associated with Kaposi's sarcoma (KS), HIV-associated Castleman's disease, and primary effusion lymphoma. As a high frequency of non-Hodgkin's lymphoma (NHL) has been reported in patients with HIV-associated KS, we hypothesized that HHV-8 infection could be indirectly implicated in the pathogenesis of NHL. We assessed the prevalence of HHV-8 antibodies in 63 patients with NHL compared with 126 HIV-infected matched control patients without NHL. Serum samples from cases and controls were assayed for antibodies to HHV-8 lytic and latent antigens using an indirect immunofluorescence assay. In patients with concordant serologic results, HHV-8 antibodies were detected in 41.5% of the NHL cases and 37% of the controls. This absence of a significant difference in HHV-8 seroprevalence between cases and controls (p =.73) does not support a possible role for HHV-8 infection in the development of NHL in HIV-infected patients. 相似文献
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64.
Immunohistochemical study of osteonectin in various types of osteosarcoma. 总被引:2,自引:0,他引:2 下载免费PDF全文
A. Schulz G. Jundt K. H. Berghuser P. Gehron-Robey J. D. Termine 《The American journal of pathology》1988,132(2):233-238
Polyclonal antibodies against osteonectin, a 32 kd non-collagenous bone protein, were applied for the histogenetic identification of variously differentiated osteosarcoma tissues. A strong positive reaction was found in matrix-producing osteosarcoma cells of the osteoblastic type, but pleomorphic or fibrosarcomatous osteosarcoma tissues reacted focally positive as well. Because the production of osteonectin depends on the osteoblastlike function of the individual tumor cell, a homogeneous immunocytochemical staining of all tumor cells cannot be expected. Nevertheless, the immunocytochemical demonstration of osteonectin in osteolytic tumors that produce no or scarcely any matrix seems to be a valuable tool for establishment of their osteogenic origin. 相似文献
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Summary Seventy-five livers with metastases were cut sagitally into 1 cm thick slices. A total number of 11,581 metastases sections was exactly mapped. There was an average of 154 metastases sections per liver. The average diameter of the metastases was 1 cm. 40% of the metastases reached to the hepatic surface, and 60% were invisible due to their deposition in the internal parenchyma. In 8% of the livers there were only superficial metastases (average 3.2 metastases), and in 12% were only deep metastases detected (average 2.6). The total number of superficial metastases increased with increasing diameter of the secondary tumors.An approximately homogeneous distribution of hepatic metastases within the liver parenchyma has been demonstrated. 相似文献
67.
The influence of serum leptin concentration on bone mass assessed by quantitative ultrasonometry in pre and postmenopausal women 总被引:1,自引:0,他引:1
OBJECTIVE: the aim of this study was to evaluate the influence of serum leptin concentration on bone mass assessed by quantitative ultrasound (QUS) in a large sample of healthy pre and postmenopausal women. DESIGN: 555 healthy pre and postmenopausal (n=261 and n=294) women (mean age, 49.5+/-17.2 years) not on hormone replacement therapy were recruited on the occasion of a routine gynecological visit. Before entry to the study, all women had answered a detailed questionnaire on important risk factors and gave written informed consent. Speed of sound (SOS), broadband ultrasound attenuation (BUA) and stiffness index (SI) of the os Calcis were measured using the Achilles ultrasonometer (GE/lunar). We systematically investigated the relation of menopause, BMI and leptin on bone mass by allocating women into the following groups: (a) premenopausal women BMI<25 kg/m(2) (N=178); (b) premenopausal women BMI>25 kg/m(2) (N=83); (c) postmenopausal women BMI<25 kg/m(2) (N=125); and (d) postmenopausal women BMI>25 kg/m(2) (N=169). Additionally we investigated the relation of serum leptin concentrations, age and BMI on ultrasonometry variables by performing a multiple linear regression analyses. RESULTS: in the initial analyses premenopausal women showed a significantly (P<0.001) lower mean age, weight, BMI, follicle stimulating hormone (FSH) and leptin concentration, a higher mean height, serum estradiol and ultrasonometry variables in comparison to postmenopausal women. Irrespective of the menopausal status, women with a BMI>25 kg/m(2) had significantly higher leptin concentrations (P<0.001) and BUA (P<0.05) whereas SOS and SI was not significant different, compared to women with a BMI<25 kg/m(2). The multiple linear regression analyses showed that only BMI but not Leptin was related to higher ultrasonometry variables, whereas increasing age was associated with a decrease in ultrasonometry variables. Furthermore, the multiple linear regression analyses confirmed that age and BMI were the only statistically significant independent predictor for ultrasonometry variables. There was no significant influence of leptin on ultrasonometry variables even after controlling for BMI or age, or BMI and age. CONCLUSIONS: serum leptin concentrations are significantly higher in pre and postmenopausal obese women, compared with normal weight controls. Ultrasonometry variables are influenced by age and BMI but not by serum leptin concentrations. 相似文献
68.
Seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 in several regions of Italy 总被引:2,自引:0,他引:2
Calabrò ML Sheldon J Favero A Simpson GR Fiore JR Gomes E Angarano G Chieco-Bianchi L Schulz TF 《Journal of human virology》1998,1(3):207-213
OBJECTIVE: To study the seroprevalence of Kaposi's sarcoma-associated herpesvirus/human herpesvirus type 8 (KSHV/HHV-8) in 779 Italian blood donors. STUDY DESIGN/METHODS: Sera were tested for antibodies to a latency-associated nuclear antigen (LANA) and a capsid related protein encoded by ORF65. RESULTS: Among all Italian donors, 17.7% and 18.7% had antibodies to LANA and ORF65 protein, respectively, and 24.1% had antibodies to at least one antigen. KSHV/HHV-8 seroprevalence was higher in the Po valley and in Sardinia than close to the sub-Alpine Veneto region, Tuscany, or Apulia. KSHV/HHV-8 seroprevalence was almost equally distributed between men and women but increased in the older age groups. CONCLUSIONS: The regional differences and age distribution in seroprevalence agree partially with the incidence of classic KS in Italy. The rarity of classic KS in KSHV/HHV-8-infected subjects and the equal gender distribution of seroprevalence suggest that other cofactors may contribute to KS development in human immunodeficiency virus type 1 (HIV-1)-uninfected individuals. 相似文献
69.
Daytime variation in performance and tiredness/sleepiness ratings in patients with insomnia, narcolepsy, sleep apnea and normal controls 总被引:3,自引:0,他引:3
Daytime tiredness or sleepiness and deficits in cognitive performance are common complaints in sleep disordered patients. Till now there are few studies comparing patients from different diagnostic groups of sleep disorders in the same experimental protocol. We studied the time course of cognitive functions and subjective alertness in a parallel group design with four groups of patients [narcolepsy, untreated or treated obstructive sleep apnea (OSA), or psychophysiological insomnia] and a control group of subjects without sleep complaints. Each group consisted of 10 subjects, matched for age and gender. After a night with polysomnography, subjects were studied for 10 h from 08:00 hours to 18:00 hours at 20 min intervals under standardized environmental conditions. Four psychological tests were applied, (1) a critical flicker fusion (CFF) test to measure optical fusion threshold (alertness); (2) a paper-and-pencil visual line tracking test (selective attention); (3) a visual analog scale (VAS) for tiredness/sleepiness; and (4) the Tiredness Symptoms Scale (TSS), a 14 items check list. Each test session lasted for 8 min, followed by a 12 min pause. The level and time course of cognitive performance and self-rating data were analysed with hierarchical linear mixed effects models. Cognitive tests showed decrements in alertness and selective attention in untreated patients with insomnia, narcolepsy, and sleep apnea. Narcoleptic patients and untreated OSA had a lower CFF threshold than controls, and for narcoleptic patients the time course differed from that of all other groups. In the visual tracking test the performance of all groups of patients was worse compared with normal controls. Self-rated tiredness/sleepiness was significantly more pronounced in the three groups of untreated patients than in control subjects. 相似文献
70.
Bone tissue engineering based on growing bone marrow stromal cells on poly(L-lactic-co-glycolic acid) fiber meshes suffers from limited matrix production and mineralization when the cells are cultured with the standard differentiation supplements (dexamethasone, beta-glycerophosphate, and ascorbic acid). To overcome this problem we included transforming growth factor beta1 (TGF-beta1), which is described as playing a key role in collagen type I formation, although its effect on mineralization is controversially discussed. The investigations focused on establishing culture conditions for the application of TGF-beta1 in three-dimensional cell culture and on the effects of different doses of TGF-beta1 (1-20 ng/mL) on bonelike extracellular matrix formation. Immunohistochemical staining showed that TGF-beta1 enhanced the formation of procollagen type I, collagen type I, and collagen type V, especially under dynamic culture conditions (orbital shaker). A long-term study confirmed positive effects on the formation of extracellular matrix, which penetrated the scaffold to a depth of 250 to 300 microm. Mineralization, qualified by scanning electron microscopy in combination with energy-dispersive X-ray analysis and evaluated by determination of the Ca2+ content per scaffold, was up to 1.7-fold increased by TGF-beta1 compared with the control. In conclusion, the growth factor TGF-beta1 seems to be effective in improving extracellular bonelike matrix formation in vitro. 相似文献