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101.
麻醉犬心房内注射复方川芎汤后血清中川芎嗪药时曲线双峰与血流动力学效应的关系 总被引:9,自引:0,他引:9
目的 探讨中药大复方体内作用规律 ,为“证治药动学”6要素中“定性定量论”提供进一步的实验依据 .方法 分别从冠状动脉定量狭窄犬和对照犬的右心房内给予复方川芎水提液 (0 .6 g· kg- 1 ) .结果 在动脉血药时 (c- t)曲线上出现了川芎嗪 (TMP)的双峰现象 ;冠状动脉狭窄犬的 TMP第 2峰显著地高于对照犬 ;而这种增高的第 2峰又与 TMP的血流动力学效应相关 .结论 可能存在机体生理和病理状态对中药复方体内命运的特殊处置规律 相似文献
102.
:目的 :研究甲硝唑磷酸酯钾 (PMP)及甲硝唑 ((MTZ)在家兔血中的药物动力学参数。方法 :家兔iv和im等量的PMP、MTZ(10 0 μmol/kg)后 ,用HPLC苦味酸内标法测定家兔血浆中PMP和MTZ的浓度。 结果 :家兔iv等量PMP和MTZ后 ,其家兔血中PMP和MTZ药 -时曲线均符合二室开放模型 ,但其PMP释出的MTZ药 -时曲线较MTZ的药 -时曲线稍低 ,前者的AUC为后者的 47 4%。家兔im等量PMP和MTZ后 ,PMP释出的MTZ药 -时曲线为一室模型 ,MTZ的药 -时曲线为二室模型。前者的Cmax较后者低 ,其AUC为后者的38 9%。结论 :家兔ivPMP和MTZ后 ,二者末端的消除速率接近 ;家兔imPMP和MTZ后 ,二者的Tp 相近。 相似文献
103.
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
104.
An oxidimetric titrant, 2,3-dichloro-5,6-dicyano-1,4-benzoquinone in anhydrous acetic acid is used for the semimicro-determination
of hydrazine hydrate, phenylhydrazine hydrochloride, isoniazid and iproniazid phosphate in pure forms as well as in some pharmaceutical
preparations containing isoniazid and iproniazid phosphate. The end point was detected potentiometrically using a platinum-calomel
combination electrode. The results obtained are compared statistically with those obtained by the official methods and they
are in good agreement. 相似文献
105.
Evaluation of a high sodium-low potassium cold-storage solution by the isolated perfused rat kidney technique 总被引:1,自引:1,他引:0
Ramella S. G.; Hadj-Aissa A.; Barbieux A.; Steghens J. P.; Colpart J. J.; Zech P.; Pozet N. 《Nephrology, dialysis, transplantation》1995,10(6):842-846
The isolated perfused rat kidney (IPK) model was used to assessinitial renal function after 24 h preservation in 3 differentcold storage solutions: EuroCollins (EC), a solution preparedaccording to the formulation of Belzer's solution (High-K+ UW)and a high Na+-low K+ Belzer UW solution (High Na+ UW). GFR and FRNa were measured after 24 h cold storage in each ofthe solutions during 60 min, and were compared to values obtainedin a control group in which renal function was measured immediatelyafter the kidneys had been harvested. ATP and CP were measuredin fresh renal tissue, in kidneys preserved for 24 h in eachsolution, in control IPK, and in reperfused IPK after they hadbeen preserved for 24 h. Main results showed that preservationin either solution caused a dramatic decrease in GFR and inFRNa within the first 60 min following reperfusion of cold-storedkidneys. However FRNa was significantly higher in the High-Na+UW group. ATP and CP content were decreased to 10% of basalvalues in all experimental groups after cold-storage. Normothermicreperfusion of IPK after cold-storage induced a restorationof ATP levels, but CP content decreased further. There was nosignificant difference in ATP and CP content between cold-storagesolutions, nor any correlation between metabolic and functionalparameters. 相似文献
106.
本文报告了氯化磷酸三销对医院污水、游泳池水、浅井水、河水的消毒试验方法和结果。结果表明:医院污水消毒加入有效氯9mg/L的氯化磷酸三钠,作用1h后可达到GBJ48—83医院污水排放标准;游泳池水消毒加入有效氯0.8mg/L作用1h后可达到游泳池水卫生标准;浅井水消毒加入有效氯0.8mg/L作用30min可达到饮用水有关卫生标准;河水消毒加放有效氯1.25mg/L作用1h,水质有很大改善,生物指标接近饮用水卫生标准。 相似文献
107.
Zeng Hui M. D. Ph. D Du Jingyuan Zheng Qixin Liu Yong Guo Xiaodong 《华中科技大学学报(医学英德文版)》1999,19(2):131-134
Summary To study the effects of tricalcium phosphate (TCP) ceramics on osteoblasts, the rat osteoblasts were cultured with the TCP
ceramicsin vitro. Scanning electron microscopy and the colorimetric methyl-thiazol-tetrazolium assay showed that the osteoblasts could adhere
well to the surface of the ceramics and the culture dish, and the proliferation of the cells was not inhibited. The results
demonstrated that TCP ceramics possessed an excellent cytocompatibility with the osteoblasts, and had some promoting effects
on proliferation of osteoblasts.
This project was supported by grant from the National Natural Science Foundation of China (No. 59493202). 相似文献
108.
Cortical metabolites and regional cerebral intracellular pH (pHi) were measured in normoglycemic (NM), acute hyperglycemic (AH), and chronic hyperglycemic (CH, 2 week duration, streptozotocin-induced) Wistar rat brains during cardiac arrest and resuscitation. During total ischemia in AH and CH rats (plasma glucose approximately 30 mM), cortical ATP, PCr, glucose, and glycogen all fell significantly as expected. Lactate levels increased dramatically in association with a concomitant intracellular acidosis. Although lactate reached higher concentrations in AH and CH than NM, pHi was significantly lower only in the AH group. With 5 min of reperfusion, all groups recovered to near baseline in all variables, though lactate remained elevated. In a separate aspect of the study, animals from each experimental group were allowed to recover for 4 days following resuscitation, with outcome being gauged by mortality rate and hippocampal CA1 neuron counts. NM survival rate was significantly better than AH and CH. In particular, no CH rats survived for 4 days despite rapid initial recovery. After 4 days, the AH group had suffered significantly greater CA1 neuron loss than the NM rats. In summary, our research identified differences in intra-ischemic acid-base status in the two hyperglycemic groups, suggesting that chronic hyperglycemia may alter the brain's buffering capacity. These observations may account for differences between acutely and chronically hyperglycemic subjects regarding outcome, and they suggest that factors other than hydrogen ion production during ischemia are responsible for modulating outcome. 相似文献
109.
Recent experimental studies on the crystallization of calcium salts at different nephron levels support the theory that the
initial formation of calcium concrements starts with an intratubular crystallization of calcium phosphate (CaP) and calcium
oxalate (CaOx). CaP seems to be the initial crystallization product in pure CaP and mixed calcium phosphate–calcium oxalate
(CaPCaOx) concrements, with the formation of CaP crystals at a nephron level above the collecting duct. Urinary macromolecules
and cellular degradation products most probably promote this process. During the passage through the collecting duct, CaP
might partly or completely dissolve at the lower pH encountered there. This might result in an increased concentration of
calcium and hence an increased supersaturation with CaOx, which in turn can bring about a heterogeneous nucleation of CaOx
on or around preformed CaP crystals or crystal aggregates. The final result will be mixed CaOxCaP or pure CaOx concrements.
Pure CaOx concrements might also be the result of an initial CaOx crystallization at nephron levels above or in the collecting
duct under conditions with a high urinary excretion of oxalate. Whether intratubular crystallization of calcium salts results
in the formation of small harmless crystals excreted with urine or calcium stones appears to be determined by a complex process,
involving kinetic factors that influence crystal growth and crystal aggregation and crystal retention.
Received: 24 December 1998 / Accepted: 11 March 1999 相似文献
110.
To examine the effect of hydroxyapatite (HAP) seed crystals and urinary macromolecules on the crystallization under conditions
similar to those in the collecting duct, we evaporated 100 ml samples of salt solutions with an ion composition assumed to
correspond to that in the collecting duct without and with HAP seed crystals. The crystallization in seeded solutions was
assessed both with and without dialysed urine (dU). After evaporation the number and volume of crystals were recorded in a
Coulter Multisizer and the crystal morphology examined with scanning electron microscopy (SEM) and X-ray crystallography.
Addition of HAP crystals was apparently followed by an approximately 15–20% increase in heterogeneous nucleation of calcium
oxalate (CaOx). In these experiments SEM and X-ray crystallography showed a high percentage of CaOx in the precipitate. In
samples reduced to 40–69 ml, addition of dU to the collecting duct solution containing HAP seed resulted in a greater mean
(SD) number of crystals; 3895 (1841) in samples with dU and 1785 (583) in samples without. This was mainly explained by an
increased mean (SD) number of small crystals. The mean crystal volume was 17.8 (1.1) and 34.3 (9.1) in samples reduced to
40–69 ml with and without dU, respectively. This might reflect the inhibitory effect of dU on the growth and/or aggregation
of the CaOx-CaP precipitate or a promoted nucleation resulting in a large number of small crystals. It is concluded that calcium
phosphate formed above the collecting duct might induce heterogeneous nucleation of CaOx at lower levels of the renal collecting
system, and that urinary macromolecules are powerful modifiers of these processes.
Received: 8 July 1998 / Accepted: 12 March 1999 相似文献