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1.
肛直肠抑制反射时门静脉血中P物质变化   总被引:1,自引:0,他引:1  
目的探讨肛直肠抑制反射(RAIR)时门静脉血中P物质(SP)的变化规律及外源性内脏神经对其变化的影响。方法将实验大白鼠分为7组,其中6组先按去与不去直肠肛管外源性内脏神经支配而分为不去神经和去神经两大组,每组中又按Foley导管上气囊置入直肠腔中的位置分为2、4、6cm组;同时再设1个对照组,将Foley导管置入直肠腔中,但不注水扩张球囊。检测并比较在直肠腔内刺激后,各组门静脉血中的SP值及变化情况。结果去神经组中2、4cm组与不去神经组之间及对照组之间,门静脉血中SP值变化比较,P〉0.05,差异无统计学意义。不去神经组中的6cm组与对照组及去神经组中2cm和4cm组之间SP值比较,P〈0.01,差异有统计学意义;去神经组和不去神经组中的6cm组之间SP值比较,P〈0.01,差异有统计学意义。结论直肠腔内上部的刺激不引出RAIR可能与该部位的刺激使内括约肌兴奋性递质(SP)的释放有关;外源性内脏神经对RAIR中门静脉血的SP变化有调控作用。  相似文献   
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Immunocytochemical methods have been used to examine the localisation of 3 neurofilament proteins and the calcium binding protein, calbindin D28k, in whole mount preparations of the submucous plexus in the Wistar rat. Neurofilament-M (160 kDA protein) was present in 40% of the submucosal neurons, staining fine filaments in the soma and the axonal processes. Calbindin D28k was present in 40% of the submucosal neurons staining both the soma and nerves within the plexus. The neurofilament proteins and calbindin D28k were never observed within the same neurons. Neurofilament-M was co-localised with substance P and calcitonin gene-related peptide but not somatostatin or the other neuropeptides investigated. Calbindib D28k was co-localised with vasoactive intestinal polypeptide and neuropeptide Y. Galanin- and somatostatin-immunoreactive neurons did not contain either the neurofilament proteins or calbindin D28k. The results demonstrate the presence of subsets of submucosal neurons that can be distinguished by the presence of neurofilament-M or calbinsin D28k.  相似文献   
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The purpose of this project was to prepare nurses to provide brief interventions for clients with alcohol or other drug (AOD) dependency in order to reduce hospitalization, morbidity, and mortality. The project was a collaborative process between a major medical center and a school of nursing. Nurses were surveyed for understanding of alcohol and other drug assessment, and a day long training was provided to teach techniques of brief interventions. The short-term results included increased knowledge of nurses about AOD assessment. Long-term results indicated that 95% of patients referred to the AOD team were confirmed to have AOD problems (Dunn & Ries, 1997). This project documents the need for nurses to have more knowledge about AOD problems and brief intervention techniques.  相似文献   
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Preliminary results on the localization of substance P-like immunoreactivity in the human cerebellum are presented. Cerebella from newborn and adult subjects were examined. While only sporadic positive fibres were detected in the adult tissue, the immunoreactive material appeared more abundant in the cerebella from newborn subjects. Varicose and non-varicose fibres and dot-like nerve terminals were present with different density in various regions. The paucity of immunoreactive perikarya suggests that most of the cerebellar substance P-like immunoreactive material has an extrinsic origin.  相似文献   
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Schistosoma mansoni infection, both in humans and in animal models, is known to induce granulomas in the liver and intestine. It has also been reported that in humans the eggs of this parasite can reach the brain, causing psychiatric and neuropathological disorders. Whether this also occurs in rodents is unknown. To answer this question, mice were infected with this parasite and the central nervous system (CNS) examined at various time intervals. The results show that schistosomiasis induced granulomas in several regions of the CNS and increased nerve growth factor (NGF) levels in the cortex, hypothalamus and brain stem, but not in the hippocampus. The infection also caused paw hyperalgesia, as determined by the hot-plate test, and a local increase in NGF, but not in substance P. These findings indicate that the murine model of infection can be used for studying mechanisms leading to human neuroschistosomiasis and suggest that the neuropathological disorders and the sensory deficits observed in human schistosomiasis are associated with impaired levels of NGF in the peripheral and central nervous system. Received: 18 January 1996 / Revised, accepted: 16 April 1996  相似文献   
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We have developed an isolated spinal cord-skin preparation of the newborn rat. The spinal cord together with a piece of skin connected to the cord by the saphenous nerve was isolated from 1- to 4-day-old rats and separately superfused with artificial cerebrospinal fluid in two neighbouring chambers. Potentials were recorded extracellularly from the third lumbar ventral root. Application of capsaicin (0.5-2 μM) or KCl (60–350 mM) with brief pressure pulses to the perfusion bath of the skin evoked a depolarizing response of 20- to 40-s duration in the ventral root. The response was depressed by [Met5]enkcphalin (0.03–3 μM). morphine (0.1–2 μM) and a tachykinin antagonist, [D-Arg1,D-Trp7,9,Leu11] substance P (spantide), 1–10 μM), applied to the spinal cord by superfusion, whereas the response was augmented by centrally administered calcitonin gene-related peptide (0.1–0.2 μM) or bicuculline (0.5–1 μM).  相似文献   
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目的 探讨感觉神经肽P物质(SP)对离体培养的肉芽组织成纤维细胞表皮生长因子(EGF)表达的调控作用及特点。方法 采用甲醛注射的方法造成Wistar大鼠局部无菌性炎性反应,提取肉芽组织进行成纤维细胞原代培养;采用逆转录—聚合酶链反应(RT—PCR)方法检测SP对肉芽组织成纤维细胞EGF基因表达的调控作用,观察时间及剂量—效应关系;采用Western-blotting方法检测EGF蛋白表达情况,观察时间及剂量—效应关系。结果 10^-7mol/L SP可诱导成纤维细胞EGF mRNA的表达,在作用后6h与对照组比,差异有显著性(P<0.01);SP在10^-8-10^-6mol/L范围内可以显著促进成纤维细胞EGF mRNA表达,在10^-7mol/L达到峰值,10^-5mol/L时与对照组差异无显著性(P>0.05)。10^-7mol/L SP作用12h后可检测到EGF蛋白明显表达增强(P<0.01),24h达高峰,48h后逐渐有所回落。SP在在10^-8--10^-5mol/L范围可诱导EGF蛋白的表达,均在10^-7mol/L剂量点达到峰值(P<0.01)。结论 SP可诱导肉芽组织成纤维细胞EGF基因和蛋白的表达,且呈现出一定的时间和剂量特点,在SP调控创伤愈合的作用中具有重要意义。  相似文献   
10.
This study examined the axonal transport of substance P-like immunoreactivity (SPLI) and its content in dorsal root ganglion, trigeminal ganglion, stomach and ileum of non-diabetic rats and two groups of rats with streptozotocin-induced diabetes of 9 months duration. One diabetic group received the aldose reductase inhibitor ‘Statil’ throughout the period of study. To reduce morbidity all diabetic animals were given twice-weekly injections of a long-acting insulin which restricted weight loss but did not prevent regular and severe hyperglycaemia. Axonal transport of SPLI was studied by measurement of accumulation at 12 h ligatures on the left sciatic nerve. There were no differences between the 3 groups either in the calculated anterograde and retrograde mean rates of accumulation (ranges 6.0 to 7.6 and 0.38 to 0.72 mm/h respectively) or mobile fractions of SPLI (means from 0.54 to 0.58). There were, however, marked reductions in anterograde and retrograde accumulations of SPLI in the constricted nerves of the ‘untreated’ diabetics (respectively 57 and 33% of controls;P < 0.01 for both). In the ‘Statil’-treated rats these deficits were attenuated (80 and 75% of controls). Diabetes also reduced the SPLI content of unligated sciatic nerve and trigeminal ganglion (65 and 75% of controls). ‘Statil’ prevented the deficit in the ganglion, but not in the nerve. ‘Statil’ treatment prevented themyo-inositol depletion and attenuated the sorbitol and fructose accumulation seen in the sciatic nerves of the untreated diabetic animals suggesting effective inhibition of aldose reductase in this tissue. The total SPLI content of the stomach and 1-cm segments of ileum were unaltered in the diabetic animals but due to the increased weights of these tissues the SPLI content per unit weight was reduced. These changes were unaffected by ‘Statil’.  相似文献   
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