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排序方式: 共有822条查询结果,搜索用时 15 毫秒
31.
32.
Takashi Tanimoto MD Toshio Imanishi MD PhD Atsushi Tanaka MD PhD Takashi Yamano MD Hironori Kitabata MD Shigeho Takarada MD PhD Takashi Kubo MD PhD Kazushi Takemoto MT Nobuo Nakamura MD Kumiko Hirata MD PhD Masato Mizukoshi MD PhD Takashi Akasaka MD PhD 《Journal of the American Society of Echocardiography》2009,22(9):1015-1021
33.
Renato G. S. Chirvi Angela Garofalo Michael J. Crimmin Lindsay J. Bawden Antonella Stoppacciaro Peter D. Brown Raffaella Giavazzi 《International journal of cancer. Journal international du cancer》1994,58(3):460-464
The synthetic matrix metalloproteinase inhibitor batimastat was tested for its ability to inhibit growth and metastatic spread of the B16-BL6 murine melanoma in syngeneic C57BL/6N mice. Intraperitoneal administration of batimastat resulted in a significant inhibition in the number of lung colonies produced by B16-BL6 cells injected i.v. The effect of batimastat on spontaneous metastases was examined in mice inoculated in the hind footpad with B16-BL6 melanoma. The primary tumor was removed surgically after 26-28 days. Batimastat was administered twice a day from day 14 to day 28 (pre-surgery) or from day 26 to day 44 (post-surgery). With both protocols, the median number of lung metastases was not significantly affected, but there was a significant reduction in the weight of the metastases. Finally, the effect of batimastat was examined on s.c. growth of B16-BL6 melanoma. Batimastat administered daily, starting at day of tumor transplantation, resulted in a significant growth delay, whereas treatment starting at advanced stage tumor only reduced tumor growth marginally. Our results indicate that a matrix metalloproteinase inhibitor can not only prevent the colonization of secondary organs by B16-BL6 cells but also limit the growth of solid tumors. 相似文献
34.
Giulia Taraboletti Gianluca Micheletti Monica Rieppi Maura Poli Michele Turatto Cosmo Rossi Patrizia Borsotti Paola Roccabianca Eugenio Scanziani Maria Ines Nicoletti Ezio Bombardelli Paolo Morazzoni Antonella Riva Raffaella Giavazzi 《Clinical cancer research》2002,8(4):1182-1188
PURPOSE: We previously reported that paclitaxel, a microtubule-stabilizing drug, inhibited angiogenesis, mainly by inhibiting endothelial cell motility (D. Belotti et al., Clin. Cancer Res., 2: 1843-1849, 1996). The aim of this study was to select a taxane with little cytotoxicity but with antimotility and hence antiangiogenic activity. EXPERIMENTAL DESIGN: Different taxanes, seco derivatives, and 14-beta-hydroxy-10-deacetyl baccatin III derivatives were tested for their effects on the proliferation and motility of human umbilical vein endothelial cells. The antiangiogenic and antineoplastic activities of the compound selected from this screening were further investigated in experimental models in vitro and in vivo. RESULTS: From the screening of different taxanes, we selected IDN 5390, a seco derivative that showed potent antimotility activity and less cytotoxicity than paclitaxel. In comparable experimental conditions, IDN 5390 inhibited endothelial cell migration without affecting proliferation. This compound dose-dependently inhibited the capacity of human umbilical vein endothelial cells plated on Matrigel to organize into a network of cords. In vivo, IDN 5390 significantly inhibited fibroblast growth factor-2-induced angiogenesis in Matrigel implants. Daily treatment with IDN 5390 in mice bearing established lung micrometastases from the B16BL6 murine melanoma caused a reduction in the size of metastases. Finally, IDN 5390 slowed the s.c. growth of the paclitaxel-resistant human ovarian carcinoma, 1A9/PTX22, xenografted in nude mice. CONCLUSIONS: The seco derivative IDN 5390 might represent the prototype of a new class of taxane derivatives with antiangiogenic properties. 相似文献
35.
Induction of chromosome-specific aneuploidy and micronuclei in human lymphocytes by metabolites of 1,3-butadiene 总被引:5,自引:1,他引:5
1,3-Butadiene is a carcinogen in rodents, but its potential carcinogenicity
to humans remains controversial. Numerous studies have shown that butadiene
and its metabolites cause sister chromatid exchanges in vitro and in vivo.
To test for other types of genotoxicity, the micronucleus assay and
fluorescence in situ hybridization (FISH) have been used to detect
chromosome damage in human lymphocytes caused by two reactive metabolites
of butadiene, diepoxybutane (DEB) and monoepoxybutene (MEB). DEB (0.5-5.0
microM) significantly increased micronucleus formation 4- to 6-fold (P
<0.01) and MEB (1-500 microM) by 2- to 4-fold (P <0.01) over control
levels. The ability of DEB and MEB to induce aneuploidy of chromosomes 7,
8, 12, and X was examined using dual-color FISH in both interphase and
metaphase cells. These chromosomes were chosen because of their involvement
in leukemogenesis. Both DEB and MEB caused dose-dependent increases in
hyperdiploidy of chromosomes 12 and X, but had no discernible effect on
chromosomes 7 and 8. These results suggest that DEB and MEB cause
chromosome-specific aneuploidy in human cells. If formed in sufficient
amounts, DEB and MEB may produce chromosome damage of the type found in
leukemia following exposure to butadiene.
相似文献
36.
37.
MT Tauber C Pienkowski P Pigeon M Cataldi P Rochiccioli 《Acta paediatrica (Oslo, Norway : 1992)》1993,82(S389):28-30
Six children presenting with partial growth hormone (GH) deficiency (mean GH peak in two different tests, 8.0 k1.3 μ g/l ) aged 8–10.3 years (mean, 2.7 ± 0.9 years) were treated for 6 months by continuous subcutaneous infusion of GH-releasing hormone(1–29)-NH, (GHRH(1–29)-NH2 ); 24-hour GH profiles and height velocity were measured. A biphasic effect of GHRH(1–29)-NH2 infusion was observed. After an early substantial increase in the 24-hour integrated concentration of GH, from 1.6 ± 0.1 to 3.5 ± 0.7 μg/l/minute, a subsequent consistent decrease occurred by 3 months, which was more pronounced after 6 months (mean 24-hour integrated concentration of GH, 1.9± 0.9 μg/l/minute). This effect reflects modification of both pulse amplitude and frequency of GH secretion. At the end of the study, one child had complete suppression of GH secretion and two others showed only one peak above 5 μg/1 during a 24-hour period. No correlation was found between these changes and height velocity. Three children did not grow significantly; the other three children who had a growth response to GHRH(1–29)-NH2 were those with the lowest 24-hour integrated GH concentration at the end of the study. The possible mechanisms involved in this biphasic effect, including GHRH antibodies, changes in somatostatin levels and/or desensitization of pituitary GHRH receptors, have been investigated. 相似文献
38.
Moderate and severe malnutrition are endemic in much of the developing world and in association with pockets of deprivation in the developed world. The cost in terms of individual and social development is high. The principles of effective management are clearly documented. A low cost, community based treatment programme for moderately and severely malnourished children under 3 years of age was established at a health centre in rural Jamaica. Children were followed up monthly and defaulters were rigorously recalled. Management consisted of carefully delivered dietary advice, antibiotics, anthelminthics, and vitamin supplements. All children improved and the response of 36 children, who were treated in the first year, showed an accelerated weight gain, with catch-up growth and the maintenance of length gain. There was a significant increase in the weight for age, at 1.9% per month over six months, which exceeds the rate reported with food supplementation programmes and nutrition rehabilitation centres. 相似文献
39.
MT Bardella N Molteni L Prampolini AM Giunta AR Baldassarri D Morganti PA Bianchi 《Archives of disease in childhood》1994,70(3):211-213
The use of follow up studies was evaluated in 128 patients with coeliac disease during their first visit to a department for adults. The original diagnosis had been made in childhood in all patients. Fifty eight (45%) of the subjects were following a gluten free diet, 23 (18%) were following a gluten free diet but with occasional gluten consumption, and 47 (37%) had adopted an unrestricted, gluten containing diet for a mean of 11.2 years. There was no correlation in individual subjects between the presence of symptoms, biochemical and immunological abnormalities, severity of histological findings, and the amount of dietary gluten, despite the greater frequency of symptoms in the group following an unrestricted diet than in the other two groups. Short stature and epilepsy with cerebral calcifications only occurred in patients following an unrestricted diet. As only diagnosis based on two or three biopsy samples and regular follow up correlated positively with dietary compliance, it is suggested that a histologically confirmed diagnosis of coeliac disease and regular lifelong follow up are essential in the management of these patients. 相似文献
40.
G Taraboletti M Morigi M Figliuzzi R Giavazzi C Zoja G Remuzzi 《Laboratory investigation; a journal of technical methods and pathology》1992,67(5):566-571
BACKGROUND: Extracellular matrix components are known to modulate mesangial cell functions as adhesion, motility and proliferation. Among other extracellular matrix components, mesangial cells have been recently described to secrete thrombospondin (TSP), a high molecular weight glycoprotein, produced by several cell types, and known to play a role in embryogenesis, wound healing, angiogenesis, and tumorigenesis. The aim of this work was the functional and molecular characterization of TSP interactions with mesangial cells. EXPERIMENTAL DESIGN: Adhesion of mesangial cells to TSP-coated plastic, and chemotaxis in the Boyden chamber assay were tested. In order to identify TSP active domains, heparin, known to bind to the amino-terminal region of TSP, four monoclonal antibodies directed against specific domains of the molecule, and TSP fragments obtained by enzymatic digestion were used. RESULTS: We found that TSP induces mesangial cell adhesion and chemotaxis, in a dose dependent manner. Adhesion was inhibited by antiserum against TSP, and by an anti-CD36 monoclonal antibody tested in the presence of heparin, but not by the peptide Gly-Arg-Gly-Asp-Ser. We have also found that only the carboxy-terminal end of TSP retains the adhesive properties of the molecule, while all the fragments tested showed some degree of chemotactic activity. CONCLUSIONS: We conclude that TSP modulates mesangial cell adhesion and motility, thus acting as a potential autocrine and paracrine regulator of mesangial cell functions in normal and pathologic conditions. 相似文献