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71.
Function of neuropeptide Y and agouti-related protein at weaning: relation to corticosterone, dietary carbohydrate and body weight 总被引:1,自引:0,他引:1
Leibowitz SF Sepiashvili K Akabayashi A Karatayev O Davydova Z Alexander JT Wang J Chang GQ 《Brain research》2005,1036(1-2):180-191
Neuropeptide Y (NPY) and agouti-related protein (AgRP), potent stimulants of feeding, have been linked in adult rats to both corticosterone (CORT) and dietary carbohydrate. To understand the significance of this relationship early in life, measurements were taken of these parameters at different ages around weaning, in rats given a choice of macronutrient diets or maintained on a carbohydrate-rich diet. The results demonstrate that, in both male and female rat pups, the expression and production of NPY and AgRP in the arcuate nucleus (ARC) peak on postnatal day 21 (P21), compared to P15 before weaning and P27 after weaning. These elevated levels of peptide were associated with peak levels of CORT and glucose and also a strong, natural preference for carbohydrate at weaning, which accounted for 55-65% of the pups' total diet. In subgroups defined by their body weight at these stages, rats with as little as 4% lower body weight (compared to higher weight pups) had 30-60% greater expression of NPY and AgRP in the ARC and elevated levels of CORT, with no difference in leptin or insulin. This response was significantly more pronounced at P21 than at P15 or P27. The importance of carbohydrate during this stage was suggested by additional results showing elevated NPY expression, CORT levels, body weight and inguinal fat pad weights in P27 pups raised on a 65% carbohydrate diet vs. 45% carbohydrate. These results suggest that hypothalamic NPY and AgRP, together with CORT, have glucoregulatory as well as feeding stimulatory functions that help mediate the transition from suckling of a fat-rich diet to independent feeding of a carbohydrate-rich diet. During this critical period, the carbohydrate together with the peptides and CORT provide the important signals, including elevated glucose, that promote de novo lipogenesis and enable weanling animals to survive periods of food deprivation. 相似文献
72.
Ermak IM Davydova VN Gorbach VI Berdyshev EL Kuznetsova TA Ivanushko IA Gazha AK Smolina TP Zaporozhets TS Solov'eva TF 《Bulletin of experimental biology and medicine》2004,137(4):379-381
In the complex with chitosan, lipopolysaccharide partially lost its ability to induce lymphokines tumor necrosis factor and interleukin-8, but retained immunostimulating properties and increased phagocytic function of macrophages by improving digestion of bacteria. 相似文献
73.
Chesnokova NB Gundorova RA Kvasha OI Bakov VP Davydova NG Beznos OV Stoliarova EP Kasakian SM Gorbacheva OA Shekhter AB Pekshev AV 《Vestnik Rossi?sko? akademii meditsinskikh nauk / Rossi?skaia akademiia meditsinskikh nauk》2003,(5):40-44
The hypothesis on the biostimulating effect of exogenous nitric oxide (NO) was made use of to develop a new method to stimulate the healing of wounds through treating them by a NO saturated gas flow. The above gas flow is generated by air-plasma unit "Plazon". The experimental and clinical studies confirmed that the NO-therapy is a highly effective treatment method for different lesions of the skin and soft tissues. We tried to use the above method in ophthalmology. A comprehensive experimental study was carried out to assess the impact of the NO-containing gas flow on the eyeball structures. An optimal mode was designed, which does not exert any influence on the intraocular pressure, Ph of the lachrymal fluid, antioxidative activity and on the proteinase-inhibitor balance in tears; no morphological changes occurred in the ocular tissue structures. The mentioned morphological and biochemical studies confirmed that the application of the NO-containing gas flow speeds up the healing, process of both an experimental cornea erosion and penetrating corneal wounds. Optimal modes of NO-therapy were defined for both types of lesions. 相似文献
74.
Infectivity enhanced, cyclooxygenase-2 promoter-based conditionally replicative adenovirus for pancreatic cancer 总被引:7,自引:0,他引:7
Yamamoto M Davydova J Wang M Siegal GP Krasnykh V Vickers SM Curiel DT 《Gastroenterology》2003,125(4):1203-1218
BACKGROUND AND AIMS: Pancreatic cancer is one of the most aggressive human malignancies. Conditionally replicative adenoviruses (CRAds) have shown some promise in the treatment of cancers. However, to date, their application for pancreatic cancer has met several obstacles: one is lack of a good control element to regulate replication, and the other is relatively low adenoviral infectivity. Thus, we constructed infectivity enhanced cyclooxygenase (COX)-2 promoter-based CRAds to develop a safe and effective therapeutic modality. METHODS: The CRAds were designed to achieve COX-2 promoter-controlled E1 expression for regulated replication (COX-2 CRAds). The infectivity-enhanced CRAds also have an RGD-4C motif in the adenoviral fiber-knob region. The selectivity and efficacy of these constructs were analyzed with cell lines in vitro. The in vivo therapeutic effect and viral replication were analyzed with a xenograft model. Pathology of the major organs and E1 RNA levels in the liver were also studied after systemic administration. RESULTS: The COX-2 CRAds showed a selective cytocidal effect in vitro in COX-2-positive cells and killed most of the pancreatic cancer cells. In vivo, intratumoral administration of the infectivity-enhanced COX-2 CRAds (10(9) particles) showed a strong antitumor effect comparable to wild-type virus, whereas the COX-2 CRAds without infectivity enhancement showed a limited effect. Viral replication was confirmed in the xenograft tumors. Systemic administration did not cause any detectable toxicity; the E1 RNA level in the liver after COX-2 CRAd administration was minimal. CONCLUSIONS: Infectivity-enhanced COX-2 CRAd is a promising agent for the treatment of pancreatic cancer. 相似文献
75.
Iushmanova TN Skripova NV Kotlova OV Ipatov ON Davydova NG 《Problemy sot?sial?no? gigieny, zdravookhranenii?a i istorii medit?siny / NII sot?sial?no? gigieny, ?konomiki i upravlenii?a zdravookhraneniem im. N.A. Semashko RAMN ; AO "Assot?siat?sii?a 'Medit?sinskai?a literatura'."》2001,(4):10-14
Dental examinations (according to WHO methods) were carried out in 447 youths aged 18-19 years, residents of Northern Russia, in Archangelsk before army service, and 500 students of Northern Medical University. Dental health of young people was characterized by high incidence and prevalence of caries (9.4.31%, CDL = 5.94), periodontal diseases, maxillodental abnormalities (72.18%), high percentage of lost teeth (8.75) in the CDL structure, poor oral hygiene (OHI-S index 3.68), and high level of need in all types of dental care, this demonstrating poor organization of health improving measures for young people before military service. Poor dental health in young people aged 18-19 years is one of the causes making them unfit for army service or fit with limitations (47 subjects for categories C, D in 1996-1998, 100-198 subjects annually for category B). 相似文献
76.
Lobko PI Kovaleva DV Kovalchuk IE Pivchenko PG Rudenok VV Davydova LA 《Morfologii?a (Saint Petersburg, Russia)》2000,118(4):36-40
Information parameters (entropia and redundancy) of cervical and thoracic spinal ganglia of albino rat foetuses, mature animals (cat and dog) and human subjects were analysed. Information characteristics of spinal ganglia were shown to be level-specified and to depend on their functional peculiarities. Information parameters of thoracic spinal ganglia of man and different animals are specie specified and may be used in assessment of morphological structures as information systems. 相似文献
77.
Cefalu WT; Wagner JD; Bell-Farrow AD; Edwards IJ; Terry JG; Weindruch R; Kemnitz JW 《Toxicological sciences》1999,52(2):49-55
Caloric restriction (CR) has been observed to retard aging processes and
extend the maximum life span in rodents. In an effort to evaluate the
effect of this nutritional intervention on physiologic variables in higher
species, several nonhuman primate trials are ongoing. In particular, a
study evaluating the independent effect of CR on the extent of
atherosclerosis was initiated in 1993 in 32 adult cynomolgus monkeys.
Therefore, the trial was designed to achieve identical cholesterol intake
after animals were randomized to a control group or a calorie-restricted
group (30% reduction from baseline caloric intake). The animals were
routinely evaluated for glycated proteins, plasma insulin and glucose
levels, insulin sensitivity, and specific measures for abdominal fat
distribution by CT scans over a 4-year interval. The results from 4 years
of intervention demonstrate that CR improves cardiovascular risk factors
(such as visceral fat accumulation) and improves insulin sensitivity. In
contrast to other primate studies with normolipidemic animals, CR had no
independent effects on plasma lipid levels and composition in the presence
of equivalent amounts of dietary cholesterol intake. Preliminary analysis
of atherosclerotic lesion extent in the abdominal aorta has failed to
demonstrate differences between control animals and CR animals. Follow- up
studies are being conducted to determine the effect of CR on
atherosclerosis extent in coronary and carotid arteries.
相似文献
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