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601.
Dan TA Eisenberg James MacKillop Meera Modi Joshua Beauchemin David Dang Stephen A Lisman J Koji Lum David S Wilson 《Behavioral and brain functions : BBF》2007,3(1):2-14
Background
Research on the genetic basis for impulsivity has revealed an array of ambiguous findings. This may be a result of limitations to self-report assessments of impulsivity. Behavioral measures that assess more narrowly defined aspects of impulsivity may clarify genetic influences. This study examined the relationship between possession of the DRD2 TaqI A and DRD4 48 bp VNTR genetic polymorphisms and performance on a behavioral measure of impulsivity, the delay discounting task (DDT), and three traditional self-report measures. 相似文献602.
Objective To evaluate the value of peak time(PT) and corrected peak time(PTc) in the assessment of left ventricular long axis systolic function in patients with dilated cardiomyopathy(DCM).Methods Thirty-one DCM cases and thirty-six healthy cases were investigated using echocardiography.To obtain image of apical four-chamber view and apical two-chamber view, PT was measured by the technique of tissue motion annular displacement.The value of PTc was corrected by R-R interval.The critical value of PT and PTc was obtained by ROC curves.Results Compared with the PT of control group, the PT of DCM group at the site of septal and lateral were significantly increased ( P <0.05), but the PT at the site of anterior and inferior were no significantly increased ( P >0.05).The PTc at the four sites were significantly increased compared with control group ( P <0.05).The areas of under the ROC curve of PTc was 0.849 (95 % CI 0.699~0.929, P = 0.000), sensitivity and specificity of diagnosis cardiac dysfunction were 80.6 % and 66.7% respectively.Conclusions The PTc was significantly increased in patients with DCM.PTc was useful to evaluate left ventricular dysfunction in DCM patients. 相似文献
603.
A Osmancevic LT Nilsen K Landin-Wilhelmsen E Søyland P Abusdal Torjesen TA Hagve MS Nenseter AL Krogstad 《Journal of the European Academy of Dermatology and Venereology》2009,23(10):1133-1140
Background Climate therapy (heliotherapy) of psoriasis is an effective and natural treatment. Ultraviolet radiation (UVB) from the sun improves psoriasis and induces vitamin D3 synthesis. Objective The aim of the study was to investigate the effect of climate therapy on vitamin D3 synthesis, blood glucose, lipids and vitamin B12 in psoriasis patients. Methods Twenty Caucasian patients (6 women and 14 men; mean age, 47.2 years; range, 24–65) with moderate to severe psoriasis [mean Psoriasis Area and Severity Index (PASI) score 9.8; range, 3.8–18.8] received climate therapy at the Gran Canarias for 3 weeks. Blood samples were drawn before and after 15 days of sun exposure. In addition, the patients’ individual skin UV doses based on UV measurements were estimated. Results Sun exposure for 15 days lead to a 72.8% (± 18.0 SD) reduction in the PASI score in psoriasis patients. Although no direct correlation was observed between PASI score improvement and UVB dose, the sun exposure improved the vitamin D, lipid and carbohydrate status of the patients. The serum concentrations of 25‐hydroxyvitamin D [25(OH)D] increased from 57.2 ± 14.9 nmol/L before therapy to 104.5 ± 15.8 nmol/L (P < 0.0001) after 15 days of sun exposure; the serum levels of 1,25‐dihydroxyvitamin D [1,25(OH)2D] increased from 146.5 ± 42.0 to 182.7 ± 59.1 pmol/L (P = 0.01); the ratio of low‐density lipoprotein cholesterol and high‐density lipoprotein cholesterol decreased from 2.4 to 1.9 (P < 0.001); and the haemoglobin A1c (HbA1c) levels decreased from 5.6 ± 1.7% to 5.1 ± 0.3% (P < 0.0001). Conclusion Climate therapy with sun exposure had a positive effect on psoriasis, vitamin D production, lipid and carbohydrate status. 相似文献
604.
Neutrophil rolling, arrest, and transmigration across activated, surface-adherent platelets via sequential action of P-selectin and the beta 2-integrin CD11b/CD18 总被引:16,自引:6,他引:10
Platelets bound to thrombogenic surfaces have been shown to support activation-dependent firm adhesion of neutrophils in flow following selectin-mediated tethering and rolling. The specific receptor(s) responsible for mediating adhesion-strengthening interactions between neutrophils and platelets has not previously been identified. Furthermore, the ability of adherent platelets to support the migration of bound neutrophils has not been tested. We studied neutrophil interactions with activated, surface-adherent platelets as a model for leukocyte binding in vascular shear flow and emigration at thrombogenic sites. Our results demonstrate that the beta 2-integrin Mac-1 (CD11b/CD18) is required for both firm attachment to and transmigration of neutrophils across surface-adherent platelets. In flow assays, neutrophils from patients with leukocyte adhesion deficiency-1 (LAD-I), which lack beta 2-integrin receptors, formed P-selectin-mediated rolling interactions, but were unable to develop firm adhesion to activated platelets, in contrast to healthy neutrophils, which developed firm adhesion within 5 to 30 seconds after initiation of rolling. Furthermore, the adhesion-strengthening interaction observed for healthy neutrophils could be specifically inhibited by monoclonal antibodies (mAbs) to Mac-1, but not to lymphocyte function-associated antigen-1 (LFA-1; CD11a/CD18) or intercellular adhesion molecule-2 (ICAM-2; CD102). Further evidence for a beta 2-integrin-dependent neutrophil/platelet interaction is demonstrated by the complete inhibition of interleukin (IL)-8-induced neutrophil transmigration across platelets bound to fibronectin-coated polycarbonate filters by mAbs to Mac-1. Thus, Mac-1 is required for firm adhesion of neutrophils to activated, adherent platelets and may play an important role in promoting neutrophil accumulation on and migration across platelets deposited at sites of vascular injury. 相似文献
605.
TA Farnsworth FRCP 《International journal of clinical practice》1998,52(6):445-446
SUMMARY Primary intracranial melanomas are rare and occur mainly in young adults. Originating from leptomeningeal melanoblasts and extending into the parenchyma, the tumours closely resemble meningiomas, from which they are radiologically difficult to distinguish despite progress in neuroimaging. Definitive diagnosis is usually made on histopathological examination, though confirmed only after post-mortem examination in some cases. Prolonged disease-free periods, and in rare cases long-term survival, are possible following successful total surgical excision. This case presented with typical clinical features but, at 79 years old, an unusual age. 相似文献
606.
Giant cell tumors of bone: treatment with radiation therapy 总被引:1,自引:0,他引:1
Records of 15 patients with giant cell tumor of bone treated with radiation therapy over a 35-year period were reviewed; ten patients for whom follow-up information was available constituted the study group. One patient was treated by means of orthovoltage equipment only, a second, by both orthovoltage and megavoltage equipment (cobalt 60). The remaining eight were all treated with megavoltage to doses of 40-52 Gy in 24-30 fractions. Seven patients are alive without disease, with an average survival of 192 months (range, 48-360 months). Three patients died of uncontrolled local and distant disease (average survival, 52 months; range, 23-99 months): one with metastasis in the lungs at time of treatment and two after treatment. Although incidence of lung metastasis appears high, it may be due to patient selection because chemotherapy had failed in all three. Complications from irradiation in one surviving patient required surgical closure of a dural fistula 19 years after treatment. No radiation-induced sarcomatous transformations of controlled tumors were noted. These data suggest that giant cell tumor of bone can be well controlled by radiation therapy. Megavoltage irradiation should be considered in treating local disease not easily controlled by surgery in the axial skeleton. Complications are minimal, and normal function can be preserved in the treated areas. 相似文献
607.
Glaab WE; Risinger JI; Umar A; Barrett JC; Kunkel TA; Tindall KR 《Carcinogenesis》1998,19(11):1931-1937
Although the resistance to the cytotoxic response of certain DNA damaging
agents has been well characterized in cells deficient in mismatch repair,
little is known about how such resistance affects mutagenesis. Using human
cancer cell lines defective in mismatch repair (MMR) and complementary cell
lines in which the MMR defects were corrected by chromosome transfer, we
present the cytotoxic effect and the mutagenic response at the
hypoxanthine-guanine phosphoribosyl transferase (HPRT) locus following
exposure to the chemotherapeutic agent, 6-thioguanine (6-TG). Upon exposure
to 6-TG, there was a differential cytotoxic response. The MMR-deficient
cells were resistant to 6-TG exposure up to 5 microM, whereas the
MMR-proficient cell lines were significantly more sensitive at the same
levels of exposure. Furthermore, the mutagenic response at HPRT induced by
6-TG was substantially increased in the MMR-deficient lines relative to the
MMR- proficient cell lines. These findings support the notion that
cytotoxicity to 6-TG is mediated through functional MMR and that resistance
to the cytotoxic effects of 6-TG is directly associated with an increase in
induced mutations in MMR-defective cells. These data suggest that the use
of 6-TG as a chemotherapeutic agent may result in the selection of
MMR-defective cells, thereby predisposing the patient to an increased risk
for developing secondary tumors.
相似文献
608.
Concern about the increasing incidence of vancomycin-resistant organisms has tempered the enthusiasm for indiscriminate vancomycin use. Cefazolin has an antibacterial activity profile similar to vancomycin against most pathogens encountered in the hemodialysis (HD) population. We evaluated the clinical efficacy and serum concentrations that were achieved during empiric cefazolin use. Fifteen consecutive HD patients (five, conventional HD; five, high-efficiency HD; and five, high-flux HD) with suspected or documented infections warranting antibiotic intervention, including access-related, respiratory tract, urinary tract, or wound infections, were enrolled. Each patient received intravenous cefazolin (20 mg/kg actual body weight rounded to the nearest 500-mg increment [range, 1 to 2 g]) after each dialysis treatment for at least three doses. Cefazolin concentrations were obtained before and immediately after the next three consecutive dialysis treatments. Thirteen patients were evaluated for efficacy and all 15 were evaluated for toxicity and cefazolin blood concentrations. All patients showed at least a short-term (3-week) clinical resolution of infection with cefazolin treatment. No central nervous system toxicities were noted and no other adverse events were expressed by the patients during the course of cefazolin treatment. Predialysis cefazolin concentrations, as determined by high-performance liquid chromatography, were 70.2 +/- 42.7 (conventional HD), 45.6 +/- 18.9 (high-efficiency HD), and 41.6 +/- 23.9 mg/L (high-flux HD) over the three dialysis sessions. Cefazolin at doses of approximately 20 mg/kg administered post-HD appears to be a safe and effective empiric therapy and yields predialysis cefazolin concentrations of 2.5 times or greater than those considered to be the minimum inhibitory concentration breakpoint (16 mg/L) for susceptible organisms. These data support the broader use of cefazolin for empiric treatment in the HD population, allowing vancomycin to be reserved for confirmed resistant organisms. 相似文献
609.
Wilms tumor in children: abdominal CT and US evaluation 总被引:1,自引:0,他引:1
Computed tomographic (CT) scans and sonograms of 13 children with Wilms tumor were reviewed to determine the ability of each imaging test to characterize the tumor and determine its extent. The findings of this review were correlated with diagnoses based on surgical and pathologic evidence. Tumor necrosis and a pseudocapsule were detected more often using CT scans than sonograms. CT scanning also was more sensitive in assessing perinephric extension, lymph node involvement, and bilateral tumors. Overall, CT scans allowed better determination of the extent of a suspected tumor, enabling correct diagnosis in 77% of patients, while US study was correct in only 23%. 相似文献
610.