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William V. Giannobile Rafaél A Hernandez Richard D. Finkelman Susan Ryarr Christopher P. Kiritsy Mark D'Andrea Samuel E. Lynch 《Journal of periodontal research》1996,31(5):301-312
Platelet-derived growth factor (PDGF) and insulin-like growth factor I (IGF-I) in combination have previously been shown to enhance periodontal regeneration. The objective of this study was to further characterize the biological effects of this combination of growth factors in non-human primates and compare the effects to those of each growth factor individually. Ligature-induced periodontitis was initiated in 10 cynomolgus monkeys. After periodontal lesions were established, surgery was performed, and either a methylcellulose gel vehicle or vehicle containing 10 μg each of either PDGF-BB, IGF-I or both PDGF-BB and IGF-I was applied to exposed root surfaces. Biopsies were taken 4 and 12 wk after treatment and the extent of periodontal regeneration was assessed by histomorphometry. At both 4 and 12 wk vehicle-treated lesions generally revealed minimal osseous defect fill (ODF) (8.5±2.1% and 14.5±5.7%, respectively) and new attachment (NA) (34.1±5.2% and 26.6±10.5%, respectively). IGF-I treatment did not significantly alter healing compared to vehicle in any parameter at both 4 and 12 wk. PDGFBB-treated sites exhibited significant (p<0.05) regeneration of NA (69.6±12.0%) at 12 wk; trends for PDGF-BB treatment effect were also observed in other parameters at 4 and 12 wk. although these increases were not statistically significant. Treatment with PDGF-BB/IGF-I resulted in 21.6±5.1 % and 42.5±8.3% ODF at 4 and 12 wk, respectively, and 64.1±7.7% and 74.6±7.4% NA at 4 and 12 wk, respectively (all significantly greater than vehicle, p<0.05). The results from this study demonstrated that: 1) IGF-1 alone at the dose tested did not significantly alter periodontal wound healing; 2) PDGF-BB alone significantly stimulated NA, with trends of effect on other parameters; and 3) the PDGF-BB/IGF-I combination resulted in significant increases in NA and ODF above vehicle at both 4 and 12 wk. 相似文献
4.
S Biasioli G D'Andrea G Micieli M Feriani D Borin S Chiaramonte A Cananzi G La Greca 《The International journal of artificial organs》1987,10(4):245-257
Serum prolactin (PRL) levels are elevated in patients with chronic renal failure (CRF) but the mechanisms responsible for these abnormalities are not fully understood. PRL secretion is undoubtedly influenced by many substances, which can be variously altered in uremia: monoamines, endogenous opiates and PTH. Our data suggest that in early renal failure PRL levels are already significantly high and the 24-h pattern of PRL secretion is significantly different from that in controls. PRL derangements could be due in mild renal failure, to unknown factors (GABA?); in severe CRF, to a major change in dopaminergic activity; in hemodialysis (HD), to a low turnover of monoamines, and in peritoneal dialysis (PD) to increased activity of serotoninergic and dopaminergic systems. 相似文献
5.
Verapamil inhibits interleukin-6 and vascular endothelial growth factor production in primary cultures of keloid fibroblasts. 总被引:10,自引:0,他引:10
G Giugliano D Pasquali A Notaro S Brongo G Nicoletti F D'Andrea A Bellastella A A Sinisi 《British journal of plastic surgery》2003,56(8):804-809
An increased secretion of cytokines and growth factors has been hypothesised to play a role in the abnormal growth of keloid fibroblasts. The aim of this study was to evaluate the effect of the calcium antagonist verapamil on the interleukin-6 (IL-6) and vascular endothelial growth factor (VEGF) secretion, as well as on cellular growth, in primary cultures of fibroblasts derived from the central part of keloid lesions. These cells grew faster than peripheral keloid and nonkeloid fibroblasts, and, in long-term cultures, became stratified assuming a three-dimensional structure. Compared with peripheral and nonkeloid fibroblasts, central keloid fibroblasts presented an increased production of both IL-6 and VEGF (P<0.03 and P<0.005, respectively). Verapamil (100 microM) decreased IL-6 and VEGF production (P<0.03 and P<0.005, respectively) in central keloid fibroblasts cultures at 72 h. Moreover, verapamil decreased cellular proliferation by 29% and increased apoptosis to an absolute value of 8%. The results of this study demonstrate that in primary cultures of central keloid fibroblasts verapamil reduces the sustained basal IL-6 and VEGF production and inhibits cell growth; these data may offer the link with the beneficial effect of calcium antagonists on keloid scars in vivo. 相似文献
6.
G D'Andrea R Joseph A R Cananzi F Ferro-Milone S Grunfeld M Toldo M A Welch 《Functional neurology》1988,3(2):179-185
The effect of short and long-term therapy with aspirin (50 mg/day) on platelet alpha granule secretion was studied in 11 healthy controls and 57 patients suffering from transient cerebral ischemic attacks (TIA) with and without accompanying diabetes and hypertension. Plasma levels of beta-thromboglobulin (beta-TG) and platelet factor 4 (PF 4) were measured as indicators of platelet alpha granule secretion. beta-TG and PF 4 levels were increased following cerebral ischemia. Aspirin treatment failed to suppress plasma levels of both proteins when measured a month and then a year after initiation of treatment. Therefore, these proteins may be poor indicators of platelet inhibition by aspirin. 相似文献
7.
S. van Ruth† EBL van Dorst‡ MR Canninga-van Dijk§ MS de Bruin-Weller† 《Journal of the European Academy of Dermatology and Venereology》2007,21(5):678-680
Cutaneous metastasis of vaginal carcinoma is extremely rare. So far, the total number of reported skin metastasis of vaginal carcinoma is only one. We present another case with an unusual manifestation of vagina carcinoma metastasis: skin metastasis presenting as a leg ulcer on the lower leg. 相似文献
8.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
9.
Peritoneal fluid concentrations of interleukin-8 in women with endometriosis: relationship to stage of disease 总被引:7,自引:10,他引:7
Gazvani MR; Christmas S; Quenby S; Kirwan J; Johnson PM; Kingsland CR 《Human reproduction (Oxford, England)》1998,13(7):1957-1961
There is increasing evidence that immunological mechanisms play a role in
the pathogenesis and pathophysiology of endometriosis. It was therefore of
interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal
fluid and peripheral blood of women undergoing laparoscopic procedures. The
presence and concentrations of IL-8 in relation to endometriosis,
infertility and abdominal pain were evaluated. Samples of peritoneal fluid
(n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive
patients undergoing laparoscopic surgery for various gynaecological
indications (abdominal pain, infertility, sterilization). IL-8 was present
in the peritoneal fluid of most women (87%). The concentration of IL-8 in
the peritoneal fluid was higher in women with endometriosis compared to
women without (P = 0.02). This difference was more pronounced in early
(stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal
fluid were also higher in women with early endometriosis compared to women
with later stages of the disease (P = 0.003). Peripheral blood
concentrations did not correlate with peritoneal fluid concentrations of
IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an
important factor that may contribute to the pathogenesis of endometriosis
possibly by promoting neovascularization. This information can be a guide
in the development of new therapeutic approaches for the treatment of
endometriosis.
相似文献
10.
The Fanconi anemia pathway is required for the DNA replication stress response and for the regulation of common fragile site stability 总被引:15,自引:0,他引:15
Fanconi anemia (FA) is a rare multi-genic, autosomal and X-linked recessive disorder characterized by hematological abnormalities, developmental defects and increased cancer susceptibility. Patient-derived FA cells display heightened sensitivity to DNA cross-linking agents such as mitomycin C (MMC). In response to DNA damaging agents, and during S-phase of the cell cycle, the FA pathway is activated via the mono-ubiquitination of FANCD2 (FANCD2-Ub), signaling its translocation to discrete nuclear foci, where it co-localizes with the central DNA repair proteins BRCA1 and RAD51. However, the exact function of activated FANCD2-Ub remains unclear. Here, we have characterized the role of the FA pathway in response to DNA replicative stress by aphidicolin (APH) and hydroxyurea (HU). The FA pathway is strongly activated in response to both agents. In addition, using patient-derived FA cell lines and siRNA targeting FANCD2, we demonstrate a functional requirement for the FA pathway in response to low doses of APH: a replicative stress treatment known to result in chromosome breakage at common fragile sites. Both the total number of chromosome gaps and breaks and breaks at the specific common fragile sites FRA3B and FRA16D were significantly elevated in the absence of an intact FA pathway. Furthermore, we demonstrate that APH activates the mono-ubiquitination of both FANCD2 and PCNA and the phosphorylation of RPA2, signaling processive DNA replication arrest. Following APH treatment, FANCD2-Ub co-localizes with PCNA (early) and RPA2 (late) in discrete nuclear foci. Our results demonstrate an integral role for the FA pathway in the DNA replication stress response. 相似文献