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991.
A pilot study is reported of costs and benefits from behavioural psychotherapy by nurse-therapists for selected neurotic problems. Figures are based on the treatment of 42 neurotics (mainly phobics and obsessive-compulsives) who completed treatment with nurse-therapists in a mean of 9 sessions (16 hours). The year before and after treatment was studied. Apart from significant and lasting reduction in patients' distress, economic benefits to them, their families and the community yielded a worthwhile internal rate of return when benefits from the cohort continue for 3 years, a reasonable assumption on available other evidence. Though untreated phobics did not improve elsewhere over 5 years follow-up, a controlled study would seem desirable.  相似文献   
992.
The purpose of this study was to evaluate the individual criteria and combination of criteria examined by operative cholangiography which make exploration of the common bile duct desirable. The overall accuracy of exploration of the common bile duct (89 per cent) was similar to that of previous series. In the normal group the accuracy of the criteria established by Le Quesne (1960) is confirmed. The most reliable criteria in the abnormal cholangiograms were the presence of single or multiple filling defects in the common bile duct, the absence of free flow of contrast medium into the duodenum and an abnormality of the terminal narrow segment. Measurements to aid assessment of free flow into the duodenum are suggested. In 34 of 40 positive explorations the common bile duct diameter was 14 mm or less; 10 common bile ducts which contained stones were less than 10 mm in diameter. Excess filling of the intrahepatic ducts was often impossible to judge in the abnormal group and was the least valuable criterion. Attention is drawn to the advantage of an immediate radiological report.  相似文献   
993.
Rickets and osteopetrosis: the osteosclerotic (oc) mouse   总被引:1,自引:0,他引:1  
A new mouse osteopetrotic mutation, osteosclerosis, has been examined with respect to rickets. These osteopetrotic mice were hypocalcemic and hypophosphatemic, and had greatly thickened epiphyseal plates with abnormalities in matrix vesicles when compared with normal littermates. Such biochemic and morphologic manifestations of rickets in this osteopetrotic mutation may explain the failure of osteosclerotic mice to be cured by transplantation of bone marrow from normal littermates and indicate that vitamin D metabolism and matrix vesicle biochemistry warrant further study.  相似文献   
994.
995.
The tendency for bacteria to develop resistance to enoxacin (Cl-919, AT-2266), a new oxyquinolone derivative, was investigated in vitro and in vivo. The mutation frequencies of Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Salmonella sp., and Haemophilus influenzae to enoxacin, norfloxacin, nalidixic acid, tobramycin, cephalexin, cefotaxime, ampicillin, azlocillin, oxacillin, and ticarcillin were determined by plating large numbers of organisms onto antibiotic-containing agar. Enoxacin resistance developed infrequently. For example, the mutation frequency of Ps. aeruginosa in the presence of enoxacin was 1 in 2.8 X 10(9) cells as compared to 1 in 1.1 X 10(6) for nalidixic acid. The increase in MIC after serial transfer through increasing concentrations of enoxacin ranged from 8-fold for Ps. aeruginosa and Staph. aureus to 256-fold for H. influenzae. Rats with chronic Ps. aeruginosa pneumonia were given subtherapeutic doses of enoxacin daily for ten weeks. Two rats were sacrificed weekly and the homogenized lungs were cultured on agar containing 5 mg/l of enoxacin and on antibiotic-free agar. No organisms resistant to 5 mg/l of enoxacin were recovered. No increase in the minimum inhibitory concentration of enoxacin for the infecting organism was seen.  相似文献   
996.
R J Baglan  J E Marks 《Cancer》1981,47(1):41-45
In this analysis, the results of brain irradiation of 39 patients with symptomatic brain metastases from oat cell carcinoma of the lung were compared with the published results of patients whose brains were irradiated prophylactically. The goals were: (1) to substantiate a clinical impression that patients with symptomatic brain metastases respond well to radiation and often experience no further neurologic deterioration until death; and (2) to compare the outcomes of symptomatic and prophylactic radiation of the brain for oat cell carcinoma of the lung. Of 39 patients with proven brain metastases who received cranial irradiation, 25 (64%) achieved complete palliation and remained free of neurologic symptoms, 4/4 (100%) achieved complete palliation; for moderate symptoms, 12/15 (80%); and for severe symptoms, 9/20 (45%). A summary of 12 reports from the literature shows that for patients with oat cell carcinoma of the lung receiving prophylactic cranial irradiation, the incidence of brain metastases is 28/525 (5%), while for patients receiving no prophylactic therapy it is 51/223 (23%). When the results of symptomatic and prophylactic cranial irradiation were compared, it was found that symptomatic irradiation controls central nervous system disease, as well as prophylactic therapy, while eliminating the need for brain irradiation in three-fourths of the patients.  相似文献   
997.
Hyperplasiogenic and tumor-promoting phorbol esters such as12-O-tetradecanoylphorbol-13-acetate or l2-O-retinoylphorbol-13-acetateinduce the sequential transient expression of the proto-oncogenesc-fos and c-myc and the ornithine decarboxylase gene in mouseskin in vivo. This sequence of biochemical events probably dependson an activation of protein kinase C by these agents. The non-irritantskin mitogens 4-O-methyl-12-O-tetradecanoylphorbol-13-acetateand ethyl phenyl propiolate do not increase the expression ofthese genes to a comparable extent. Thus, 12-O-tetradecanoylphorbol-13-acetateand 12-O-retinoylphorbol-13-acetate induce epidermal hyperproliferationby different biochemical mechanisms as do 4-O-methyl-12-O-tetradecanoylphorbol-13-acetateand ethyiphenyipropiolate.  相似文献   
998.
Efforts to prevent Haemophilus influenzae type b (HIB) infections in infancy have been hampered by the low immunogenicity of capsular polysaccharide vaccines in children younger than 18 mos. In searching for alternate immunogens, we have studied the protective potential of polysaccharide-poor, lipid-rich endotoxin (LPS) core in experimental HIB infections. Because all gram-negative bacteria have similar LPS core structures, we were able to use as vaccine the J5 mutant of Escherichia coli 0111, the LPS of which consists only of core components, and thus to avoid problems in interpretation arising from vaccine contamination with non-LPS HIB immunogens. Mice were given graded inocula of HIB and developed lethal infection analogous to human HIB disease when virulence was enhanced with mucin and hemoglobin. After active immunization with heat-killed E. coli J5, 40/50 (80%) of infected mice survived, compared with 14/50 (28%) of saline-immunized controls (P less than 0.005). Passive immunization with rabbit antiserum against E. coli J5 prevented lethal HIB infection when administered 24 or 72 h before or 3 h after infection. This protection was abolished by adsorption of antiserum with purified J5 LPS, with survival reduced from 14/24 to 0/24 (P less than 0.005). Furthermore, rabbit antiserum to purified J5 LPS gave just as potent protection against death as antiserum to whole J5 cells. These studies demonstrate that immunity to core LPS confers protection against experimental murine HIB infection and provide the framework for a new approach to prevention of human disease from HIB.  相似文献   
999.
1000.
Oxygen uptake and steady-rate energy output of 7 obese male and 13 obese female adolescents (greater than 178% ideal body weight) walking at four different speeds (1.167, 1.5667, 1.7833, and 2.125 m/s) were studied. Body composition was measured by hydrostatic weighing, and steady-rate energy output by open circuit spirometry. Energy output was expressed as kJ/min (kcal/min) and indexed to body mass and fat-free mass. A 2-by-4 ANOVA (sex by speed) revealed significant differences in the energy output between the speed conditions. There was no significant difference between the sexes. A nonlinear increase in calorie output with increasing speed indicated a decreasing efficiency with increasing speed of walking. Possible reasons include biomechanical factors such as increased upper-body forward lean needed to maintain balance at faster speeds of movement, increased energy output due to increased inertia, extra energy output needed to accelerate the limbs and torso, and increased body fat.  相似文献   
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