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101.
102.
Mild social stress abolishes the effects of isolation on anxiety and chlordiazepoxide reactivity 总被引:1,自引:0,他引:1
Rationale: Social isolation is anxiogenic and may change the effects of anxiolytic drugs. These effects are generally attributed to
”isolation stress”. However, isolation does not affect basal corticosterone levels; thus, it cannot be considered stressful.
On the contrary, isolation deprives animals of mild daily stressors that are inherent to social life. Since mild stressors
were shown to be anxiolytic in rats, it was postulated that short-term, repeated stressors may abolish the effects of isolation. Objectives: The aim of the present study was to investigate whether short-term, repeated, mild social stress can abolish the consequences
of isolation on anxiety and on the effects of chlordiazepoxide. Methods: Rats were housed in groups or in individual cages for 5 days (isolates). Half of isolates were daily submitted to the attacks
of a resident rat for 30 min per day, on 4 consecutive days (stressed isolates). On day 5, rats were treated either with vehicle
or with chlordiazepoxide and submitted to the elevated plus-maze test. Endocrinological consequences of experimental manipulations
were assessed in a different set of rats. Results: Plasma ACTH and corticosterone levels were similar in the three groups. Weight gain was higher, while plasma growth hormone
was lower in stressed isolates, both effects being consistent with a mild stress. Isolation had a clear anxiogenic effect.
This effect was completely abolished by the daily experience of social stress. Chlordiazepoxide had a significant anxiolytic
effect in all three groups. Its effects on classical plus-maze variables did not differentiate the three groups. However,
chlordiazepoxide decreased risk assessment activity only in isolates. Conclusions: The lack of appropriate endocrinological changes challenges the concept of ”isolation stress”. However, isolation was anxiogenic
in our study and it also induced subtle changes in the effects of chlordiazepoxide. It appears that mild daily stressors have
a protective effect against the effects of isolation.
Received: 23 May 1998 / Final version: 3 December 1998 相似文献
103.
Rats were treated chronically with -methyl-p-tyrosine methyl-ester HCl (-MT) twice daily for 0–14 days. At 1 h after the (last) -MT injection, d-amphetamine sulphate was given and motor activity was measured in an ANIMEX activity meter for 4 h. Amphetamine-induced excitatory and stereotyped behaviour was scored according to a rating scale in a separate experiment. A single dose of -MT markedly reduced the activity response after amphetamine. After 1–3 days of -MT treatment, tolerance to its amphetamine-antagonistic affect started to develop, reaching a maximal degree after 7–14 days. The pattern of the amphetamine response, monophasic in control rats, became biphasic in the -MT tolerant rats with an early (at 0–1 h) and a late (2–4 h) peak of motor activity. The late peak appeared within 3 days, while the early peak appeared after 7 days of -MT treatment. The results on amphetamine-induced excitatory and stereotyped behaviour in essence agreed with the motor-activity data. It is concluded that tolerance to the amphetamine-antagonistic action of -MT is not complete. Its rate of development varies in a complex pattern, indicating the presence of more than one mechanism of tolerance. 相似文献
104.
Résumé Notre étude porte sur les toxicomanes en difficulté du fait de leur consommation de drogue dans le canton de Vaud; elle s'étend de 1974 à 1978 et bénéficie du concours de la police cantonale, d'hôpitaux, d'instituts médico-sociaux et de centres sociaux. L'observation porte sur 1519 cas de consommateurs de drogues dures, 1993 consommateurs de drogues douces et 186 cas d'abus chronique sévère de médicaments seuls.Pour les drogues dures, l'effectif annuel des cas nouveaux âgés de moins de 20 ans culmine en 1976. Quant aux «anciens» toxicomanes, leur effectif ne cesse d'augmenter. L'héroïne est la drogue la plus utilisée; elle est associée dans un quart des cas aux amphétamines, elles-mêmes remplacées par la cocaïne dès 1978. Les premières cohortes importantes d'héroïnomanes dans le canton de Vaud auront 28 à 30 ans en 1980.Pour les drogues douces, les effectifs enregistrés diminuent légèrement au cours des cinq ans d'observation. La participation des jeunes est particulièrement élevée, les anciens consommateurs sont beaucoup moins nombreux. L'usage de drogues dures ou douces concerne deux hommes pour une femme.L'abus sévère de médicaments touche un petit groupe plus âgé à prédominance féminine, qui varie peu au cours des cinq ans d'observation.
Drug-addiction in the canton of Vaud, 1974–8
Summary Our study is concerned with drug-addicts in the Swiss canton of Vaud who are in difficulties as a result of their drug consumption. The survey covers the period from 1974 until 1978, and was carried out with the assistance of the cantonal police, hospitals, sociomedical institutes, and social assistance centres. We investigated:1519 cases of consumers of hard drugs (opiates, amphetamines, and cocaine)1993 consumers of soft drugs (haschisch and hallucinogens)186 cases of serious chronic abuse of medicaments only, which were accidentally discovered by our information systemWith hard drugs, the annual number of new cases in the age group below 20 shows a peak in 1976, and remains so far at a level one third below. As far as older subjects are concerned, mostly old drug-addicts, the total number in the age group 20–29 continues to increase year after year. In exchange, in the age group 30 and older, the level of addiction to hard drugs remains constant and low. Heroin is drug number one, and is in 25 % of the cases associated with amphetamines, which are replaced by cocaine since 1977–8. It should be noted that the first bigger group of heroin-addicts in the canton of Vaud will be 28–30 years old in 1980. By the end of 1978, the total number of subjects addicted to hard drugs might amount to at least 830.The total number of subjects recorded as addicted to soft drugs decreased slightly in the course of the five years under observation. The percentage of young addicts is particularly high, while there are much fewer old consumers. Every third addict to hard or soft drugs is a woman.Abuse of medicaments is limited to a small group, which is older, consists predominantly of women, and varies little in the course of the five years under observation.The collected material is discussed in the light of data published in the foreign literature.
Drogenabhängigkeit im Kanton Waadt, 1974–1978
Zusammenfassung Unsere Untersuchung bezieht sich auf die Drogenabhängigen, welche zwischen 1974 und 1978 im Kanton Waadt durch ihren Drogenkonsum in Schwierigkeiten gekommen sind. Sie wurde ermöglicht durch die Mitwirkung der Kantonspolizei, von Spitälern, sozialmedizinischen Instituten und sozialen Einrichtungen. Folgende Gruppen von Drogenabhängigen wurden erfasst:1519 Konsumenten von harten Drogen (Opiate, Amphetamine, Kokain)1993 Konsumenten von weichen Drogen (Haschisch, Halluzinogene)186 Fälle von schwerem chronischem Medikamentenmissbrauch, welche zufällig durch unser Informationsnetz erfasst wurdenBei den harten Drogen erreicht die Anzahl der jährlichen neuen Fälle unter 20 Jahren 1976 den Höhepunkt und hält sich seither um einen Drittel unter diesem Niveau. Die Älteren sind meist schon Langzeitkonsumenten. Die Anzahl der 20- bis 29jährigen nimmt mit den Jahren ständig zu, die der 30jährigen und älteren bleibt gering und konstant. Heroin ist die meistgebrauchte harte Droge; in einem Viertel der Fälle wird es kombiniert mit Amphetaminen; diese werden seit 1977/78 durch Kokain ersetzt. Die ersten bedeutenden Kohorten von Heroinabhängigen im Kanton Waadt werden 1980 28 bis 30 Jahre alt sein. Die Gesamtzahl der Konsumenten von harten Drogen im Kanton Waadt dürfte Ende 1978 bei mindestens 830 liegen.Bei den weichen Drogen nimmt die Anzahl der registrierten Fälle im Laufe der fünf Jahre etwas ab. Der Anteil der Jungen ist hier besonders hoch. Langzeitkonsumenten sind hier weniger zahlreich. Der Konsum von harten und weichen Drogen betrifft doppelt so viele Männer wie Frauen.Schwerer Medikamentenmissbrauch wurde vor allem bei über 30jährigen angetroffen, vorwiegend bei Frauen. Im Laufe der fünf Jahre hat sich hier kaum etwas geändert.Die Angaben werden im Lichte der ausländischen Literatur diskutiert.相似文献
105.
Jan-Olof Fernberg Rolf Lewensohn Sven Skog 《Medical oncology (Northwood, London, England)》1991,8(2):63-67
The effect of melphalan on cell loss, cell growth and cell-cycle traverse was studied on the human myeloma cell line RPMI 8226. Melphalan treatment resulted in arrest of cells in late S- and G2-phases in a population of unsynchronized cells. At high concentrations of melphalan (e.g. 40 μm), cell loss was noticed duringthe first cell cycle after melphalan treatment in addition to the aforementioned arrest of cells in late S and G2. The cell loss after melphalan treatment was further analysed in cells enriched for G1-phase. Cell death in this population of cells occurred between 24 and 48 hr after treatment as the cells were in S and moving over to G2. 相似文献
106.
Prolongation of the ejaculation latency in the male rat by thioridazine and chlorimipramine 总被引:1,自引:0,他引:1
Thioridazine (3 mg/kg) and chlorimipramine (1.5–6.0 mg/kg) prolonged the ejaculation latency and increased the number of mounts but did not change the number of intromissions preceding ejaculation. Blockade of peripheral and central noradrenaline receptors by phentolamine and phenoxybenzamine respectively resulted in a suppression of all aspects of the sexual behavior with increasing doses. dl-5-HTP (25–100 mg/kg) in combination with an inhibitor of peripheral 5-HTP decarboxylase (benserazide, 25 mg/kg) produced, like chlorimipramine and thioridazine, a prolongation of ejaculation latency and an increase in the number of mounts preceding ejaculation. Selective inhibition of 5-HT reuptake however, by zimelidine (0–20 mg/kg) or alaproclate (0–20 mg/kg) did not affect the mating behavior. At higher doses of these drugs some animals failed to initiate sexual activities. There was an increase in the postejaculatory interval but no change in the ejaculatory latency.It is concluded that the prolonged ejaculation latencies observed following treatment with thioridazine or chlorimipramine is not due to a blockade of central or peripheral adrenergic -receptors. 相似文献
107.
Steady-state kinetics of imipramine in patients 总被引:1,自引:0,他引:1
Lars F. Gram Ib Søndergaard Johannes Christiansen Gorm Odden Petersen Per Bech Niels Reisby Ilse Ibsen Jørgen Ortmann Adam Nagy Sven J. Dencker Ove Jacobsen Ole Krautwald 《Psychopharmacology》1977,54(3):255-261
Steady-state plasma level kinetics were studied in 76 patients given imipramine (IP) 150 to 225 mg/day for 2–5 weeks. IP was given in three divided doses at 8.00 a.m., 1.00 p.m. and 5.00 p.m. Plasma concentrations of IP and its active metabolite desipramine (DMI) were determined by quantitative in situ thin-layer chromatography. The plasma levels of IP and DMI showed pronounced flucutations throughout the day with a ratio of about 2 between highest and lowest level. Patients with steady-state levels of IP and/or DMI below 50 g/l reached this within 1 week of treatment. Patients with higher steady-state levels reached steady-state concentrations within 2–3 weeks. There were some intraindividual fluctuations in plasma levels from week to week after steady state had been reached (coefficient of variation: 10–20%). Interindividually, the steady-state levels corrected to a dose of 3.5 mg/kg per day varied considerably: IP: 6–356 g/l, DMI: 24–659 g/l and IP+DMI: 58–809 g/l. The steady-state plasma levels showed a skew distribution that became normal by logarithmic transformation. The IP/DMI ratio ranged from 0.07 to 5.5 with a median value of 0.47. Compared to data from amitriptyline treated patients the IP/DMI ratios had significantly lower median value and larger variation than the corresponding plasma level ratios of amitriptyline/nortriptyline. Several statistically significant differences in steady-state levels between age groups were found. For IP: Women aged 30–39 had lower levels than women aged 20–29, 40–49, and 50–59, and men aged 50–59 and 60–65; men aged 30–39 had lower levels than men aged 60–65. For DMI: Women aged 30–39 had lower levels than women aged 50–59. 相似文献
108.
Haller J Millar S van de Schraaf J de Kloet RE Kruk MR 《Journal of neuroendocrinology》2000,12(5):431-436
Recently we demonstrated that corticosterone exerts an acute facilitatory effect on aggression in male rats. Corticosterone production reaches a maximum at the onset of the dark period, while male rats are more aggressive in the dark. Here we present evidence demonstrating that the corticosterone increase at the beginning of the dark period is causally linked to the increase in aggressiveness. We measured plasma corticosterone and quantified aggressive behaviour of male territorial rats at various time points of the day-night transition. Low aggression levels were observed in the full light period when plasma concentrations of corticosterone were low. An increase in plasma corticosterone occurred just prior to the dark phase, when aggressive responding was the highest. Aggressive behaviour remained high in the early dark period when corticosterone was still high. We found that blocking the high affinity mineralocorticoid receptor (MR) with spironolactone (5 or 10 mg/kg) during the early dark period dramatically and specifically reduced territorial aggression. 相似文献
109.
Richard J Bessell‐Browne Sven Thonell 《Journal of Medical Imaging and Radiation Oncology》2004,48(2):248-250
A case of an infant with an asymmetrical head is presented. On clinical assessment the patient displayed features of deformational plagiocephaly. With the aid of three‐dimensional CT imaging of the skull, a bipartite parietal bone was diagnosed. The prevalence and possible aetiology of a bipartite parietal bone is discussed as well as a brief overview of the common causes of plagiocephaly. 相似文献
110.
Neil E Martin Thomas B Brunner Krystina D Kiel Thomas F DeLaney William F Regine Mohammed Mohiuddin Ernest F Rosato Daniel G Haller James P Stevenson Debbie Smith Barnali Pramanik Joel Tepper Wesley K Tanaka Briggs Morrison Paul Deutsch Anjali K Gupta Ruth J Muschel W Gillies McKenna Eric J Bernhard Stephen M Hahn 《Clinical cancer research》2004,10(16):5447-5454
PURPOSE: Preclinical and clinical studies have demonstrated that inhibition of prenylation can radiosensitize cell lines with activation of Ras and produce clinical response in patients with cancer. The aim of this study was to determine the maximally tolerated dose of the dual farnesyltransferase and geranylgeranyltransferase I inhibitor L-778,123 in combination with radiotherapy for patients with locally advanced pancreatic cancer. EXPERIMENTAL DESIGN: L-778,123 was given by continuous intravenous infusion with concomitant radiotherapy to 59.4 Gy in standard fractions. Two L-778,123 dose levels were tested: 280 mg/m2/day over weeks 1, 2, 4, and 5 for dose level 1; and 560 mg/m2/day over weeks 1, 2, 4, 5, and 7 for dose level 2. RESULTS: There were no dose-limiting toxicities observed in the eight patients treated on dose level 1. Two of the four patients on dose level 2 experienced dose-limiting toxicities consisting of grade 3 diarrhea in one case and grade 3 gastrointestinal hemorrhage associated with grade 3 thrombocytopenia and neutropenia in the other case. Other common toxicities were mild neutropenia, dehydration, hyperglycemia, and nausea/vomiting. One patient on dose level 1 showed a partial response of 6 months in duration. Both reversible inhibition of HDJ2 farnesylation and radiosensitization of a study patient-derived cell line were demonstrated in the presence of L-778,123. K-RAS mutations were found in three of the four patients evaluated. CONCLUSIONS: The combination of L-778,123 and radiotherapy at dose level 1 showed acceptable toxicity in patients with locally advanced pancreatic cancer. Radiosensitization of a patient-derived pancreatic cancer cell line was observed. 相似文献