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71.
Ozasa K Higashi A Yamasaki M Hayashi K Watanabe Y 《Environmental health and preventive medicine》1997,2(2):85-88
Differences observed by comparing the responses to two surveys taken 5 years apart were compared with self-reported changes
in dietary habits in the second survey to examine the construct validity of dietary change. That is, when an observed difference
about a certain food was consistent with a self-reported change, these two methods seemed to show a high validity regarding
dietary change. Both surveys used the same self-administered food intake frequency questionnaire, and subjective changes in
food intake were evaluated at the second survey (self-reported change). Eight hundred fifty-five males and one thousand females
aged 30-69 years were analyzed. Since results by both methods showed a higher frequency of increased intake of green-yellow
vegetables in general, pale- colored vegetables in general, carrots, and squash, these results were thought to be of high
validity. However, cabbage, lettuce, and seaweeds showed inconsistent results regarding higher frequencies of intake. Changes
among quintiles of lower frequency seemed to show lower validity because the results obtained by the two methods were often
inconsistent for dairy foods and some other foods. Thus, self-reported changes may reflect respondents’ attitudes toward foods,
not their actual behavior. 相似文献
72.
Omoto M Imai T Seki K Nomura R Otahara Y 《Environmental health and preventive medicine》1997,2(3):105-116
Based on the fact that chemical products such as binding agents are produced by mixing three kinds of phosphates with different
ratios, we mixed metaphosphate, polyphosphate and pyrophosphate. Each was made to Na-phosphate, K-phosphate, and Ca-phosphate
and each was mixed with commercial feeds so that the content of P would be approximately 0.1, 0.15, 0.3, 0.4, 0.6 and 1.0%.
The prepared pellets were given to ICR, CF # 1 and AKR strains of mice at 29 days of age for 680 days and observations were
made through this experimental period at different stages. The observations were also carried out on the mice administered
with the experimental feeds for 1.5 months from 9 to 10.5 months of age. The observations were compared with those of the
control group at all times. As a result, plasma 1 α, 25 (OH)2 D3 and P levels were always significantly higher in the phosphate administered groups relative to the control. Urine P and Fe
increased while urine Ca decreased in the phosphate-treated groups.
The effect of phosphates on the bones was studied taking soft X-ray pictures of hind legs and applying microdensitometry to
them. Through these observations we recognized thinning of the cortex of bones, reduction of marrow trabecules and development
of osteophyte. Histological observations disclosed that changes in knee joint tissues were apparent; that is, a decrease in
or an irregular loss of the number of cells in superficial, intermediate, and radial strata of the joint cartilage, proliferation
of subchondral bone, and the development of osteophytes were noted. As for muscles, diameters of musclar fibers became smaller;
in particular, type II fibers showed greater shrinkage. Regarding kidneys, swelling and atrophy of glomerular capillaries,
proliferation of mesangial cells, nephroselerosis, swelling, thinning, and loss of tubular epithelium, interstitial tissue
inflammation, development of cylindruria, and deposition of calcium were observed. All these changes seem to be a particularly
advanced aspect of the changes which are more pronounced with increasing dose and age.
These changes were found even in the group administered with the feed containing 0.1% phosphorus, and, these changes were
dependent on the concentration level of P. It was observed that administration to older subjects for a short term (1.5 months)
produced effects stronger than those to younger subjects administered for a long term (10.5 months).
The effects of condensed Ca-phosphate on bones were similar to those of condensed Na- and K-phosphates, and, hence, it was
supposed that these effects were caused by phosphate radicals.
An erratum to this article is available at . 相似文献
73.
Fowle Iii JR 《Environmental toxicology and pharmacology》1997,4(3-4):247-250
Many Environmental Laws create the unrealistic expectation that science can be used to determine ‘safety'. The many uncertainties surrounding environmental risks, as well as individual, group and societal differences about what is considered ‘safe', make it inevitable that policy decisions must be made. It is appropriate that such decisions be shaped by politics and social issues, as well as be informed by science and economics, but care should be taken to distinguish between policy and fact. Not much is known about the nature and magnitude of environmental susceptibilities. Credible environmental decisions require that scientists, risk assessors and decision-makers acknowledge this, and that they take care to distinguish policy calls from scientific fact. 相似文献
74.
Induction of food intake by a noradrenergic system using clonidine and fusaric acid in the neonatal chick 总被引:1,自引:0,他引:1
To clarify noradrenergic systems on food intake of the neonatal chicks, we examined the effects of i.c.v injection of clonidine (CLON), an alpha2-receptor agonist, and fusaric (5-butylpicolinic) acid (FA), a dopamine (DA)-beta-hydroxylase (DBH) inhibitor. Although a high dose (250 ng) of CLON induced a narcoleptic response and reduced food intake, food intake at 30 min post-injection was enhanced by lower doses (25 and 50 ng) of CLON. Central administration of FA (25, 50 and 100 microg) increased food intake in a dose-dependent fashion. It is suggested that feeding behavior is stimulated by low levels of CLON and decreased by further production of norepinephrine (NE), and FA may play the disturbance of sleeping and then enhance food intake. 相似文献
75.
76.
The effects of the biogenic amine reuptake inhibitors fluoxetine, clomipramine and imipramine on the behaviour of rats after chronic treatment with
9 tetrahydrocannabinol (
9-THC) for 5 and 10 days were examined. Rats with permanently in-dwelling IV cannulae were injected twice daily with doses of
9-THC (2–6 mg/kg).
9-THC treatment reduced the rate of body weight gain and induced the typical biphasic modifications of behaviour. Tolerance developed to both of these effects. On days 6 and 11 of the experiment, rats were injected IP with 15 mg/kg imipramine HCl, clomipramine HCl or fluoxetine HCl, and behaviour, consisting of writhes, backward kicks, jumps and wet shakes, was observed for the next 30 min. Each of the amine reuptake inhibitors induced changes in behaviour, the severity of which appeared to correlate with their ability to inhibit the reuptake of 5-hydroxytryptamine (5-HT). It is suggested that tryptaminergic mechanisms are involved in the production of a withdrawal-like behaviour after chronic
9-THC treatment. 相似文献
77.
Fernando Santos James C. M. Chan James D. Hanna Kazuhiko Niimi Richard J. Krieg Jr Martha D. Wellons 《Pediatric nephrology (Berlin, Germany)》1992,6(3):262-266
To investigate the effects of growth hormone (GH) on the reversal of growth failure in uremia, recombinant human GH (rhGH) was administered to rats with chronic renal failure (CRF). The dosage of rhGH was 3 IU/day (i.p.) for 13 days after the induction of CRF by 5/6 nephrectomy. Animals were classified into four groups: untreated nephrectomized rats (NX,n=40), GH-treated nephrectomized rats (NX+GH,n=18), sham-operated rats fed ad libitum (SHAMAL,n=27), and sham-operated rats pair-fed with 10 NX rats (SHAMPF,n=10). NX and NX+GH rats developed a similar and moderate degree of CRF, serum urea nitrogen being (mean±SEM) 49±3 and 54±4 mg/dl, respectively, compared with 16±4 and 19±0 mg/dl in SHAMAL and SHAMPF groups. Weight (56.0±3.3 g) and length (3.5±0.1 cm) gains of NX rats were lower than those of SHAMAL rats (94.2±4.0 g,P<-0.0001 and 4.1±0.2 cm,P<-0.01). Growth of the SHAMPF group and the matched NX rats was not significantly different. Weight (56.2±5.0 g) and length (3.4±0.2 cm) gains of NX+GH and NX rats were similar, the beneficial effect of GH therapy on growth being observed in only those animals with more severe degrees of uremia. This growth-promoting action resulted from greater food efficiency and not from stimulated food intake. The hypercholesterolemia seen in NX rats, 81±2 mg/dl versus 55±3 mg/dl in SHAMAL (P0.0001), was not increased in the NX+GH group, 87±3 mg/dl. There was a positive and significant correlation between serum cholesterol and serum urea nitrogen values in NX and NX+GH animals. This study suggests that growth impairment of mild CRF is mainly due to malnutrition and is refractory to GH administration. GH therapy improves the growth rate of animals with advanced CRF without aggravating their lipid abnormalities. 相似文献
78.
A J Parker T Mehta N S Zarghami P K Cusick B E Haskell 《Toxicology and applied pharmacology》1979,47(1):135-143
This paper provides the first evidence that the Lathyrus sativus neurotoxin, l-3-oxalylamino-2-aminopropionic Acid (OAP), is toxic when administered intraperitoneally to a primate with a mature bloodbrain barrier. Drowsiness, vomiting, muscle tremors, twitching, convulsions, and death occurred in young male squirrel monkeys (Saimiri sciureus) following injection of 4.26 and 11.4 μmol (0.750 and 2.00 mg) OAP/g body wt. Electroencephalographic changes characteristic of each stage of intoxication were observed. Unchanged OAP was recovered from brain of intoxicated animals. These observations support a possible role for OAP in the etiology of human neurolathyrism, a paralytic disease prevalent among adults in Central India who have consumed large quantities of L. sativus seeds for several months. 相似文献
79.
Neonatal mice 1 and 5 days of age and older mice 25 days of age were injected with an increasing dose of monosodium glutamate (MSG) for a ten-day period and observed for at least 150 days. Both male and female animals in the 1- and 5-day age group treated with MSG showed large increases in weight over controls along with a shortened body length. The MSG group also showed decreases in locomotor and explatory behavior. The 25-day animals took much longer to show effects or failed to show any effects, indicating that the MSG-induced changes studied are age dependent. Possible methodological considerations accounting for conflicting reports in the MSG literature are discussed in light of the present findings. 相似文献
80.
Subjective and functional results after total gastrectomy: prospective study for longterm comparison of reconstruction procedures 总被引:7,自引:0,他引:7
Shinya Adachi Satoshi Inagawa Tsuyoshi Enomoto Eiji Shinozaki Tatsuya Oda Toru Kawamoto 《Gastric cancer》2003,6(1):0024-0029
Background:
Many reconstruction procedures have been developed in efforts to resolve patients' complaints after total gastrectomy. However,
there have been few reports of longterm comparisons between reconstruction procedures, especially with regard to the prevention
of duodenal food passage. This study was undertaken to compare the longterm subjective and functional results among Roux-en-Y
esophagojejunostomy (R-Y), R-Y with pouch (P-Y), and jejunal interposition with pouch (P-I) after total gastrectomy.
Methods:
Consecutive patients requiring curative total gastrectomy were enrolled in this prospective study by the envelope method.
Results:
Hospital stay was longer following a P-I than an R-Y or a P-Y. Over 50% of R-Y patients complained of heartburn, and 20%
of R-Y patients showed dumping syndrome throughout the postoperative period, with this rate being significantly different
from rates in the other two groups. P-Y patients complained of early satiety in the late postoperative period, while P-I patients
complained of early satiety in the early postoperative period. The nutritional index in P-I patients was higher than those
in patients with the other two procedures. Gastrointestinal and hepatobiliary dual scintigraphy (GHDS) showed that the rate
of bile reflux with an R-Y was relatively high after surgery. Food reflux with a P-Y was increased (9.4% to 11.1%), but with
a P-I food reflux was decreased at 3 years after surgery (13.3% to 9.9%). Patients with a P-Y had a faster recovery of body,
weight in the early postoperative period; however, at 5 years after operation, body weight recovery with a P-I was greatest.
Conclusion:
Reconstruction should be performed with pouch formation after total gastrectomy with curative intent.
Received: March 7, 2002 / Accepted: September 26, 2002
Acknowledgments This study was partly supported by the University of Tsukuba Research Project.
Offprint requests to: S. Adachi 相似文献