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91.
Mice killed shortly after receiving c. 2000 spores of a type E strain of Clostridium botulinum per os were incubated at one of five chosen temperatures together with bottles of cooked meat medium seeded with a similar inoculum. After incubation the rotting carcasses were homogenized. Sterile membrane filtrates of the homogenates (10%, w/v) and pure cultures were then titrated for toxicity. Some of the main findings were confirmed with two further type E strains. Toxicity produced at 37 degrees C was poor in both carcasses and cultures (200-20,000 mouse intraperitoneal LD/g or ml). It was good in both systems at 30 and 23 degrees C, usually reaching 20,000-200,000 LD/g or ml, and in carcasses occasionally more; at 30 degrees C maximal toxicity was reached more quickly in carcasses than in cultures. Prolonged incubation (36-118 days) at 30 or 23 degrees C resulted in complete loss of toxicity in virtually all carcasses but not in cultures. At 16 degrees C the development of toxicity in carcasses was strikingly greater than in cultures. At 9 degrees C neither system produced more than slight toxicity after prolonged incubation. Trypsinization increased the toxicity of cultures but not usually of carcasses. Unfiltered carcass homogenate (10%, w/v) with maximal intraperitoneal toxicity was harmless for mice by mouth in doses of 0.25 ml. These findings differed in important respects from those made earlier with a type C strain. 相似文献
92.
K A Burkman R W Gaines S R Kashani R D Smith 《Archives of physical medicine and rehabilitation》1988,69(2):132-134
Herpes zoster probably occurs more often than generally thought. Since it produces a radicular distribution of pain, it should be included in the differential diagnosis of radiculopathy. A case is presented in which evaluating the radicular low back pain before the characteristic rash appears was misleading. Careful history-taking concerning the exact nature of the pain and sensory changes is needed to differentiate between zoster and radiculopathy, if no rash is evident. 相似文献
93.
J. Kralovanszky N. Prajda S. Kerpel-Fronius T. Bagrij E. Kiss G. J. Peters 《Cancer chemotherapy and pharmacology》1993,32(3):243-248
Selective protection of the normal host tissues from the toxic effects of anticancer agents would allow the use of higher, probably more effective, doses of the drugs. It has been demonstrated that delayed high-dose uridine administration after 5-fluorouracil decreases the extent of myelosuppression and causes faster regeneration of the bone marrow. We studied the biochemical consequences of the gastrointestinal toxicity caused by 5-fluorouracil and the potential of high-dose uridine treatment to influence these adverse effects. 5-Fluorouracil caused dose-related decreases in the biochemical parameters (thymidine kinase, sucrase, maltase, alkaline phosphatase) selected as early markers of the impaired metabolic activity of the intestinal mucosa. The nadir of the biochemical changes was reached between 24 h and 72 h after 5-fluorouracil treatment, and complete regeneration of the mucosa took 6–7 days. Delayed high-dose uridine administration failed to mitigate the severity of the gastrointestinal damage that ensued after 5-fluorouracil treatment, but caused significantly earlier regeneration of the mucosa. 相似文献
94.
In 82 CHD male patients aged 35-54 years with well-preserved working capacity (threshold load, 600-750 kgm/min) who had underwent bicycle ergometer test, the time course of changes in the major hemodynamic parameters was found to be significantly similar to that of healthy individuals. The cases who stopped performing bicycle ergometer tests because of anginal attacks, and ST segment depression or either showed a more significant elevation in systolic and diastolic blood pressure at the maximum load rate and lower increase in heart rate than in healthy subjects, which may be regarded as a compensatory mechanism that prevents a further decrease in coronary flow. Diminished increase in stroke index and cardiac index suggests reduced myocardial contractility. 相似文献
95.
M D Silverstein D A Albert N M Hadler M W Ropes 《Journal of clinical epidemiology》1988,41(7):623-633
96.
SRIVASTAVA Z. I.; MATHUR N.; RASTOGI S. K.; GUPTA B. N. 《Occupational medicine (Oxford, England)》1988,38(4):134-136
Eighty-nine cases of chronic bronchitis were matched against167 asymptomatic controls from the glass bangle industry ofFirozabad. Factors of age, social status, smoking habit andduration of exposure were studied. Duration of exposure wasfound to be a factor contributing significantly to the causationof disease.
Requests for reprints should be addressed to: Dr B. N. Gupta, Division of Epidemilogy, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow P.O. Box 80, 226001, India 相似文献
97.
98.
David A. Hughes Graham C. Smith Joyce E. Davidson Anna V. Murphy T. James Beattie 《Pediatric nephrology (Berlin, Germany)》1996,10(4):445-447
. Neutrophil-mediated tissue damage has been implicated in the pathogenesis of diarrhoea-associated haemolytic uraemic syndrome
(D+ HUS). This study evaluates priming and activation of the neutrophil oxidative burst in D+ HUS using chemiluminescent techniques.
Peripheral blood neutrophils from 11 children with acute D+ HUS were examined. No difference was found in the oxidative burst
of neutrophils from patients and controls. Serum elastase levels were measured in 8 patients and found to be significantly
elevated. Although elastase results suggest neutrophil activation, chemiluminescence studies do not confirm this in the peripheral
blood neutrophil. This does not support a significant role for circulating agents in priming and activating the peripheral
blood neutrophil.
Received August 17, 1995; received in revised form and accepted November 27, 1995 相似文献
99.
I K Shkhvatsabaia A N Kravchenko P V Avdonin M Iu Men'shikov A A Nekrasova 《Kardiologiia》1988,28(5):72-77
Platelet activation factor (PAF)-, ADP and vasopressin-induced increments of platelet Ca2+ concentration were measured by quin-2 in 64 patients with essential hypertension and 16 normal donors. Basal concentration of free Ca2+ was 87 +/- 4 nM in donors, 106 +/- 5 nM in patients with labile hypertension (LH) and 122 +/- 6 nM in those with stable hypertension (SH) (p less than 0.01). PAF, ADP and vasopressin, added to platelets, increased [Ca]in by 448 +/- 58, 397 +/- 66, and 277 +/- 50 nM, respectively, in the donors, by 473 +/- 57, 479 +/- 54 and 195 +/- 32 nM, in LH patients, and by 607 +/- 85, 584 +/- 73 and 245 +/- 41 nM in SH patients. There were no significant variations between the three samples, using the ANOVA test. In 20 patients, whose both parents had essential hypertension, [Ca]in increment was 738 +/- 8 nM for PAF, 682 +/- 90 nM for ADP, and 320 +/- 61 nM for vasopressin. In 19 patients, who admitted to no essential hypertension in the family, these parameters were significantly lower: 310 +/- 40 nM for PAF, 389 +/- 61 nM for ADP, and 147 +/- 26 nM for vasopressin. The demonstrated changes may be making an important contribution to the maintenance of elevated vascular tone and provide an evidence in favor of a genetically-predetermined EH variety. 相似文献
100.
Confounders contributing to the reported associations of coffee or caffeine with disease 总被引:2,自引:0,他引:2
G B Schreiber M Robins C E Maffeo M N Masters A P Bond D Morganstein 《Preventive medicine》1988,17(3):295-309
The role of caffeine or coffee in causing or promoting the incidence of serious disease is equivocal. Two design factors may account for the discrepancies in reported findings on the effects of coffee drinking: (a) imprecision of measurement and (b) confounding variables. A study of 2,714 white U.S. adults disclosed that, of 32 risk factors analyzed by linear and logistic regression, only sex and cigarette smoking were found to be important potential confounders of caffeine and coffee intake. Partial R2 values of the other 30 risk factors were relatively small and were inconsistent for each sex. It is unlikely that any of these factors could explain any of the reported associations between caffeine or coffee consumption and certain diseases. However, certain weak associations with caffeine or coffee intake should be included in the study design when they are known to be risk factors of a disease under investigation. These factors for men are dietary fat intake, vitamin C intake, and body mass index; and for women are vitamin use, alcohol intake, stress, and perceived health status. 相似文献