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81.
鸡后根神经节多巴胺细胞在体及体外培养中的免疫细胞化学观察 总被引:2,自引:0,他引:2
应用免疫细胞化学PAP法,研究了鸡胚和雏鸡后根神经节细胞内多巴胺递质的表现与胚胎发育过程中的变化,并在细胞培养条件下研究了周围靶组织——皮肤对后根节细胞胚胎发育的影响。鸡后根节细胞内多巴胺的免疫反应最先出现于E_(10),只占后根节细胞的0.8%,E_(18)时达5.6%,出壳后雏鸡为8.6%。在鸡后根节内,多巴胺免疫反应阳性细胞主要为较大的A类细胞,和极少较小的B类细胞。免疫反应阳性的周围神经末梢位于皮肤和交感干内。当取自E_9的鸡胚后根节细胞经7天培养后,部分神经细胞出现多巴胺免疫反应阳性;而取自E_6的鸡胚后根节细胞虽经10天培养后仍为免疫反应阴性;然而,将取自E_6后根节细胞与皮肤组织联合培养10天后,少量神经细胞及轴突出现多巴胺免疫阳性反应。作者认为:鸡后根节多巴胺细胞在胚胎时期的发育有赖于周围靶组织的作用。 相似文献
82.
A randomized controlled trial of goserelin and medroxyprogesterone acetate in the treatment of pelvic congestion 总被引:3,自引:0,他引:3
Following identification of the proportion of pelvic congestion among symptomatic patients complaining of chronic pelvic pain, and in a totally asymptomatic group of patients requesting tubal ligation, the efficiency of goserelin acetate versus medroxyprogesterone acetate was compared objectively using pelvic venogram scores, and subjectively by symptom resolution, improvement of psychological status and sexual functioning in a prospective randomized trial in 47 patients with pure pelvic congestion syndrome. Patients received either goserelin acetate (3.6 mg/month for 6 months) or medroxyprogesterone acetate (MPA; 30 mg/day for 6 months). Among patients with chronic pelvic pain, those with pure pelvic congestion were mostly parous, had the most severe pelvic signs and symptom scores, lowest rates of sexual functioning, and higher states of anxiety and depression as compared with others. At 1 year after treatment, goserelin remained superior to MPA in terms of pelvic venographic improvement as an objective measure. In alleviation of signs and symptomatology, improvement of sexual functioning and reduction of anxiety and depressive states as subjective measures, goserelin acetate achieved a statistically significant advantage (P = 0.0001) compared with MPA. 相似文献
83.
M. E. Verberne A. C. Gittenberger-de Groot R. E. Poelmann 《Anatomy and embryology》1998,198(3):171-184
We were interested in the contribution of the cardiac neural crest to the complete anterior and posterior nerve plexus of
the chick heart. This includes the pathways by which these cardiac neural crest-derived neuronal precursors enter the heart.
As lineage techniques we used the traditional quail-chick chimera in combination with the newly introduced technique of retroviral
reporter gene transfer to premigratory cardiac neural crest cells. Retrovirally infected embryos (n=23) and quail-chick chimeras (n=19) between stages HH27 and 40, were immunohistochemically evaluated, using the lineage markers LacZ (retroviral reporter)
and QCPN (anti-quail nuclear marker), respectively and the neuronal differentiation markers HNK-1, RMO-270 and DO-170. Between
stages HH27 and 33, quail-derived and LacZ positive cells were situated around the arterial cardiac vagal branches at the
arterial pole, and vagal branches along the anterior cardinal veins and the sinal vagal branch at the venous pole. From stage
HH35 onward, QCPN/LacZ-positive cardiac ganglia were observed throughout the anterior and posterior plexus and were mainly
concentrated in the subepicardium near the distal ends of the arterial cardiac vagal branches and the sinal cardiac vagal
branch respectively. From stage HH36 both the anterior and posterior plexus contained a population of large cardiac ganglion
cells and a population of smaller cells along nerve branches as well as in the cardiac ganglia, which means that differentiation
starts in both plexus at the same time. Furthermore only nerve fiber connections between the anterior and posterior plexus
were observed. These results show that the cardiac neural crest contributes to the cardiac ganglion cells from both the entire
anterior and posterior plexus. Furthermore these results suggest that these precursor cells enter the arterial pole via the
arterial cardiac vagal branches and the venous pole via the sinal cardiac vagal branch without intermixing. Finally we show
that in addition to the cardiac ganglia, the cardiac neural crest contributes to small myocardial glia or undifferentiated
cells along nerve fibers, and some myocardial nerve fibers as well as nerve tissue in the adventitia of the large veins at
the venous pole and in the adventitia of the coronary arteries.
Accepted: 30 March 1998 相似文献
84.
BACKGROUND: Some patients with endometriosis are candidates for sympathectomy of the superior hypogastric plexus. The objective of this paper is to describe our technique of laparoscopic presacral neurolysis for sympathectomy and to report 1 year results of the first 15 cases. METHODS: To achieve this objective in a prospective observational study of 1 year follow-up; we performed laparoscopic presacral chemical neurolysis with phenol in 15 patients with pelvic pain and minimal-moderate endometriosis. The main outcome measures were: the impact of treatment on pelvic symptom resolution, non-opioid analgesic consumption during menses, sexual performance and observed complications and side effects during 1 year follow-up. RESULTS: We noted a significant reduction in total pelvic symptom score as compared with baseline mean (SD) of 9.04 (1.2). The mean difference [95% confidence interval (CI)] of reduction was 5.7 (4.9-6.5), 5.8 (5.0-6.6) and 5.8 (4.9-6.6) from the baseline at the 3rd, 6th and 12th postoperative month (P < 0.001). We observed a significant improvement in Sabbatberg Sexual Rating Scale as compared with baseline mean (SD) of 30.9 (4.3). The mean difference (95% CI) of increase was 33.4 (30.3-36.4), 33.2 (30.1-36.2) and 33.2 (30.1-36.3) from the baseline at the 3rd, 6th and 12th postoperative month. We observed a significant reduction in analgesic consumption during menses in terms of total naproxen sodium tablets as compared with baseline mean (SD) of 8.9 (1.1). The mean difference (95% CI) of reduction in the total number of naproxen sodium 250 mg tablets was 6.5 (5.5-7.5), 6.7 (5.7-7.7) and 6.6 (5.6-7.6) from the baseline at the 3rd, 6th and 12th postoperative month. The most common side effect was constipation. CONCLUSION: Laparoscopic presacral neurolysis is feasible and simple. More data is needed to support its efficacy and safety. 相似文献
85.
I. Rodriguez-Moldes J. P. Timmermans D. Adriaensen M. H. A. Groodt-Lasseel D. W. Scheuermann R. Anadon 《Anatomy and embryology》1990,181(4):389-391
Summary Using an antibody raised against a purified chick duodenal vitamin D-dependent calcium-binding protein, the presence and distribution of calbindin has been studied immunohistochemically in the habenular ganglia of the dogfish. In the more developed left ganglion, a positive reaction was clearly observed in the neurons of the medial nucleus, whereas in the lateral nucleus, only some scarce, hardly immunostained cells appeared. In the neurons of the right habenula however, no immuno-reactivity was observed. The distribution of vitamin D-dependent calcium-binding protein in the dogfish habenulae is therefore asymmetrical. This may be due to differences in the neuronal activity between the two ganglia. 相似文献
86.
Arnaldo Ferroni A. Galli M. Mazzanti 《Pflügers Archiv : European journal of physiology》1996,431(6):954-963
Neuronal cell firing is crucial to nerve-nerve communication. The ability to produce consecutive action potentials is related
to the activation of inward currents after each upstroke. If fast Na current is indeed responsible for the overshoot, it is
still unclear which current drives membrane voltage to the Na threshold. In this study we present evidence that in adult rat
sensory neurones a dihydropyridine-sensitive Ca channel exists in addition to the well characterized L-type, or high-threshold
Ca channel. During stimulated action potential trains, L-type Ca channels open during the excitation wave, whereas activity
of the other dihydropyridine-sensitive Ca channel was observed primarily between action potentials. This second Ca pathway
shows remarkably long openings at negative potentials after a series of positive prepulses. The nerve action potential and
the repetitive firing work as a physiological Ca channel facilitation mechanism. Therefore, we suggest that this novel Ca
conductance provides inward current, between two consecutive action potentials, able to modulate the frequency of neuronal
bursts.
Received: 3 August 1995/Received after revision: 9 October 1995/Accepted: 10 October 1995 相似文献
87.
Masuda Y Kim SK Kato T Iida S Yoshida A Tachibana Y Morimoto T 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,161(3):397-404
The cortical masticatory area (CMA) elicits rhythmic jaw movements in response to repetitive stimulation and is involved in the control of mastication. Based on jaw movement patterns, the CMA is divided into two parts. One is the part of the CMA in which a T-pattern similar to jaw movements during food transport in natural mastication is evoked by electrical stimulation. The other is more dorsomedially located, and during chewing a C-pattern similar to jaw movements can be induced. However, it is still not known which region of the putamen receives projections from the CMA and whether projections originate from both parts of the CMA. In this study, electrophysiological and histological experiments were undertaken in rabbits to investigate projections from the CMA to the putamen. Both experiments showed that the ventral region of the putamen received projections from the CMA. The density of the projections from the CMA area inducing the T-pattern seemed to be higher than that from the area inducing the C-pattern. Furthermore, the peak latency of the evoked potentials from stimulation of the CMA area inducing the T-pattern was shorter than that from stimulation of the area inducing the C-pattern. The data obtained from the present study indicate the functional role of the ventral region of the putamen in the regulation of mastication, and further suggest that the corticostriatal pathway is involved in the transition between behavioral jaw movement patterns. 相似文献
88.
M. Kimura T. Aosaki Y. Hu A. Ishida K. Watanabe 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1992,89(3):473-477
Summary The aim of this report was to investigate the neural processes of movement initiation and control in which the basal ganglia play an essential role. Single-neuron activity was recorded in the putamen of monkeys performing learned arm movements initiated in three different modes: sensorially guided, internally-timed self-initiated and memory guided. There were no significant differences in the magnitude and timing of both prime mover and supporting muscle activity between the three modes of movement. Over half of the task-related neurons showed strong activity in one of the three modes of movement initiation, but were only slightly activated in the other two modes. No clear preference for a particular movement mode was evident in the population of putamen neurons as a whole. These results are consistent with the hypothesis that there are heterogeneous groups of neurons in the putamen, and that each group of neurons participates in retrieving a different kind of information required for movement based on either external sensory events or on internally stored information. 相似文献
89.
Yu. I. Arshavsky G. N. Orlovsky Yu. V. Panchin 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1985,59(1):203-205
Summary Efferent neurons in isolated pedal ganglia of the pteropodial mollusc Clione limacina were filled with Lucifer Yellow through the wing nerves. Then the ganglia were illuminated with intense blue light which resulted in the complete inactivation of these neurons. After inactivation of efferent neurons, interneurons of the pedal ganglia continued to generate the locomotor rhythm. 相似文献
90.
Immunohistochemical studies were performed to address the expression of the high-molecular-weight component of the neurofilament triplet NF200 (a marker of neurons forming A fibers) and the binding of isolectin B4 (IB4) by neurons of the L4-5 spinal ganglia after ligation or section of the sciatic nerve in rats. A total of 15% of neurons in the ganglia of intact rats expressed NF200. By 90 days after nerve ligation, the proportion of NF200+ neurons decreased two-fold; administration to these rats of the nerve regeneration stimulator xymedone increased the number of NF200+ neurons by 50.7% compared with controls (ligation, no treatment). In intact rats, 23.6% of neurons bound IB4. The proportion decreased by 2.6% 30 days after nerve ligation and to undetectable levels by 90 days; xymedone increased the proportion of surviving IB(4)+ neurons more than eight-fold. IB(4)+ neurons were more likely to enter post-traumatic apoptosis. Ligation of the nerve was followed by survival of fewer NF200+ and IB(4)+ neurons than section of the nerve, which suggests that axon lengthening is a factor maintaining neuron survival. The pyrimidine derivative xymedone increased the survival of neurons of both subpopulations, especially IB(4)+ neurons. 相似文献