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This study is a small collection of the natural history of smoking of 865 persons - all smokers and majority (97.11%) of them were males, more than 80% were between 21-50 years, most (90%) were Hindus and 75% were service holders. It revealed that most of the subjects started smoking between 10 and 25 years of age, frequently being requested by their friends but felt nothing mentionable at their first experience. Most of them (64%) were smoking for more than 10 years, 48.56% were smoking more than 10 cigarettes in a day, filter-tipped more often (by 64% subjects) and without any history of break by 56% subjects. Majority (80%) used to inhale the smoke and 40% had no specific time of choice. Most of the subjects (80%) like to smoke in deep thoughts, 66% during excitement, 60% when depressed, 82% when relaxed and 62.5% when alone. But most of them (64%) did not smoke when busy. Majority (70.87%) felt relaxed when smoking. Most of the people (45%) stood reasonable having no cigarette in their stock. Majority (84%) used to smoke even when not offered. Tobacco was consumed largely as smoke by 75% subjects; 78% subjects smoked only cigarettes and about half of the smokers smoked even when they did not enjoy it. 相似文献
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In order to examine the effect of chronic neuroleptics on spinal dopaminergic system, rats were treated with haloperidol (0.5 mg/kg IP) for 21 days and the monosynaptic mass reflex (MMR) as well as dopamine (DA) metabolism were investigated. MMR, recorded from ventral root L6 following supramaximal stimulation to ipsilateral dorsal root L6 in spinalized rats, were found to be unaffected following chronic haloperidol treatment when compared to control. Apomorphine (0.1 mg/kg IV) caused 10-20% depression of MMR in control animals which was augmented to 40-50% in chronically haloperidol-treated animals suggesting an upregulation of DA receptors in the spinal cord. DA content of lumbar region of the spinal cord was unaffected whereas its major metabolite, homovanillic acid, was significantly reduced in chronic haloperidol-treated animals. This decreased utilization of DA may compensate the upregulation of DA receptors to maintain the physiological homeostasis of the spinal dopaminergic system. 相似文献
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The ability of the cholestatic steroid glucuronide, estradiol-17 beta-(beta-D-glucuronide) (E(2)17G), to inhibit the hepatic clearance (ClH) and biliary secretory rate maximum (SRm) of taurocholate was investigated in the recirculating and single pass isolated perfused male rat liver. In the recirculating perfused liver, E(2)17G (0, 2, 4, or 6 mumol) was added as a bolus dose to the reservoir at zero time while taurocholate was infused into the portal vein in increasing amounts (15, 30, 45, or 60 mumol/mL; 1 mL/hr for 15 min each). E(2)17G (4 mumol) caused a significant (P less than 0.05) inhibition of bile flow and bile acid secretion at 10-15 min during infusion of 15 mumol/hr taurocholate but did not inhibit the SRm which occurred at 42 min, indicating that E(2)17G had not caused an irreversible inhibition of taurocholate transport. E(2)17G (6 mumol) caused a profound and irreversible inhibition of bile flow attributable to retention of E(2)17G in the liver. The noncholestatic estradiol-3-(beta-D-glucuronide) (E(2)3G; 6 mumol) had no significant effect on bile flow or the SRm. In the single pass perfused liver (10 mL/min flow rate), E(2)17G (0, 1, 2, 5, or 10 nmol/mL) or E(2)3G (2 nmol/mL) was added to the perfusate resulting in a stable infusion to the liver. [3H]Taurocholate was infused into the portal vein in increasing amounts to give inflow concentrations (Cin) of 25, 50, 75 or 100 nmol/mL. In the absence of E(2)17G, taurocholate ClH decreased from 0.92 to 0.70 mL/min/g liver with increasing taurocholate concentrations. Neither E(2)17G nor E(2)3G altered the ClH of 25 nmol/mL taurocholate. E(2)17G (10 nmol/mL) inhibited bile flow and bile acid secretion first at 20-25 min, followed by inhibition of ClH of 75 and 100 nmol/mL taurocholate (35-60 min). In contrast, E(2)3G stimulated bile acid secretion and increased the SRm by 80%. Thus, at doses that did not block its own elimination, E(2)17G did not cause an irreversible inhibition of taurocholate transport into bile. E(2)17G did not directly inhibit the uptake of taurocholate into the liver but first inhibited the biliary excretion of taurocholate, resulting in its intrahepatic accumulation and decreased clearance from the perfusate. 相似文献
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BACKGROUND: Several plants are traditionally used as birth control agents by the rural people in India. Mimosa pudica is one of the folk medicinal plants commonly used as antifertility agent in some places in India. The present work was carried out to evaluate the claimed antifertility effect of the plant by carrying out pharmacological studies with the root extract of the plant. STUDY DESIGN: Air-dried roots of M. pudica were extracted using methanol. Dried methanol extract of the root was administered orally to Swiss albino mice for 21 consecutive days. Estrous cycle, reproductive hormones (LH, FSH, prolactin, estradiol and progesterone) and number of litters produced were studied in both control and extract-administered groups by using standard methods. Phytochemical studies of the methanolic root extract were carried out using qualitative and thin-layer chromatography methods. RESULTS: M. pudica root extract, when administered orally at a dose of 300 mg/kg body weight/day, prolonged the length of the estrous cycle with significant increase in the duration of the diestrous phase and reduced the number of litters in albino mice. The number of litters was increased in the posttreatment period. The analysis of the principal hormones (LH, FSH, prolactin, estradiol and progesterone) involved in the regulation of the estrous cycle showed that the root extract altered gonadotropin release and estradiol secretion. CONCLUSIONS: The root extract of M. pudica has antifertility effect as it prolongs the estrous cycle and disturbs the secretion of gonadotropin hormones in albino mice. The decrease in FSH level in the proestrus and estrus stages in the extract-administered group compared with those of control animals indicates the disturbance of estrous cycle and ovulation through suppression of FSH. 相似文献
138.
Effect of Escherichia coli on Fluid Transport across Canine Small Bowel MECHANISM AND TIME-COURSE WITH ENTEROTOXIN AND WHOLE BACTERIAL CELLS 总被引:22,自引:2,他引:22 下载免费PDF全文
R. L. Guerrant U. Ganguly A. G. T. Casper E. J. Moore N. F. Pierce C. C. J. Carpenter 《The Journal of clinical investigation》1973,52(7):1707-1714
An Escherichia coli strain isolated from a patient with severe cholera-like diarrhea elaborates a partly heat-labile enterotoxin shown to cause prompt adenyl cyclase stimulation and isotonic fluid secretion by canine jejunum. Both responses disappear upon removal of the enterotoxin. The duration of action of a submaximal dose of this E. coli enterotoxin was brief, despite sustained exposure to the jejunum, suggesting inactivation of the enterotoxin by its interaction with the mucosa. 相似文献
139.
Structuring a safer donor-replacement program 总被引:1,自引:0,他引:1
BACKGROUND: Replacement donors are more likely than volunteer donors to have positive or abnormal tests for transfusion-transmissible disease. In an effort to increase the donor pool, workers sought to identify a safer replacement-donor subgroup that may be acceptable for routine donations. STUDY DESIGN AND METHODS: In a retrospective review and cohort study, the replacement-donor effect was separated from the new- donor effect. The relative effect the replacement donor has on the risk of transfusion-transmissible diseases, donor retention, and frequency of returning donations was then quantified by comparison against the effect of repeat volunteer donors. RESULTS: The replacement donor had 3.1 times the risk and 0.72 times the donor retention rate and made 0.81 times as many returning donations as the repeat volunteer donor. The figures for the new-donor effect were similar. The two risks were additive, making a new replacement donor particularly hazardous. If replacement donations only from repeat replacement donors were considered, the donor risk and the number of donations per returning donor were made comparable to those for the general (combined) volunteer donor. CONCLUSION: The negative effect of the replacement donor is similar in magnitude to that of the new volunteer donor. A replacement-donation program targeting repeat replacement donors has an acceptable risk profile and may be a valuable adjunct to the collection of blood from general volunteer donors. 相似文献
140.