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961.
This review covers four topics.1) Placental pathology in Himalayan mountain people. To determine morphological changes of the placenta at high altitude, pathological examination was made of 1000 Himalayan placentas obtained in Nepal and Tibet and the results compared with Japanese placentas delivered at sea level. Characteristic findings in the placental villi of the Himalayan group included high incidences of villous chorangiosis and chorangioma. These processes were clarified by ultrastructural observation.2) Placentation in Sirenians. The giant Takikawa sea cow, which lived 5 million years ago, was discovered on Hokkaido, Japan. It was an ancestor of the dugong as well as the manatees. Sirenia, the sea cow group, shares a common ancestor with Proboscidea, the elephants, even though they now inhabit quite different environments. A comparison was made of their zonary endothelial type of placentation.3) Placentation in sharks and rays. The remarkable placentation of hammerhead sharks and manta rays is described.4) Placentation in the Antarctic minke whale. Placental tissue samples of this whale were obtained from the Japan Institute of Cetacean Research. In an ultrastructural study of the utero–placental junction, microfilamental processes of the allantochorionic zone and crypt formation were visualized.  相似文献   
962.
Objective: To investigate whether moxibustion affects the secretion of catecholamine as a-drenalin, noradrenaline and dopamine. Methods: Twenty Wistar rats were allocated to two groups. One was moxibustion-group (10 rats), and the other was non-moxibustion-group (10 rats). Four ignited moxa-cones were applied to bilateral "Shenshu" (肾俞 BL 23). When a moxa-cone burned out, another one was replaced. At the end of each experiment, blood sample (2 mL/rat) was collected from the heart for assaying plasma adrenalin, noradrenaline and dopamine contents with high pressure liquid chromatography. Results: The presented results showed that plasma adrenalin and noradrenaline contents of moxibustion-group are significantly higher than those of non-moxibustion-group (P<0.01). However, there is no significant difference of dopamine between moxibustion- and non-moxibustion- groups (P >0.05). Conclusion: These results demonstrated that moxibustion stimulates the secretion of adrenaline and noradrenaline in normal rats.  相似文献   
963.
964.
BACKGROUND AND OBJECTIVES: It is our hypothesis that stellate ganglion block increases regional blood flow on the blocked side, but does not change cardiac output, suggesting that the corresponding regional blood flow on the contralateral side may decrease, which would be disadvantageous for patients with bilateral sympathetically-maintained pain. The aim of this study is to examine the effect of stellate ganglion block on facial skin blood flow. METHODS: Skin blood flow on the right and left forehead was measured by a laser blood flowmeter before stellate ganglion block and 15 minutes after the block. The block was performed for 8 outpatients with acute or chronic pain in the head or neck using a 24-gauge needle, 5 mL of 1% mepivacaine, and a paratracheal approach at the C6 transverse process. Time control without the block was obtained with 9 healthy volunteers. RESULTS: All the patients developed the Horner's syndrome on the blocked side, but not on the contralateral side. The facial skin blood flow increased from 7.5 +/- 1.1 mL/min/100 g to 14.5 +/- 1.4 mL/min/100 g on the blocked side (P < .01) and from 8.8 +/- 1.2 mL/min/100 g to 12.8 +/- 1.7 mL/min/100 g on the contralateral side (P < .05). The healthy volunteers without the block showed no significant change (from 10.1 +/- 0.8 mL/min/100 g to 10.3 +/- 0.7 mL/min/100 g). CONCLUSIONS: Our study suggests that stellate ganglion block may increase the contralateral regional skin blood flow.  相似文献   
965.
Objectives  To investigate the effect of snack eating on salivary cortisol and chromogranin A (CgA). Methods  From 14∶00 to 18∶00, starting two hours after consumption of a midday meal, saliva samples were collected every 30 minutes from 15 healthy males, 7 of whom (snack group) ate a snack immediately after the sampling at 15∶00. Salivary cortisol and CgA levels were determined by ELISA. Samples were controlled according to salivary flow rates. Results  For the snack group, after snack consumption, salivary cortisol increased to exceed significance (p<0.05) at 15∶30 and rose even higher at 16∶00. In the control group, there was no such change. There was no significant change in salivary CgA in either the snack group or the control groups during the sampling period. Conclusions  These findings suggest that no food should be consumed for at least 90 mins before saliva sampling for cortisol determination and that salivary CgA is probably not affected by snack eating.  相似文献   
966.
This study was performed to determine whether the addition of norepinephrine to local anaesthetics prolongs epidural analgesia in man. In addition, cerebrospinal fluid norepinephrine (NE) concentrations were measured. In the first part of the study, epidural catheters were inserted in 14 patients before herniotomy. Mepivacaine, 1.5 per cent (0.35 ml.kg-1), was administered and norepinephrine (5 micrograms.ml-1) was added in seven patients. The duration of anaesthesia was prolonged from 54 +/- 11 min to 83 +/- 12 min (P less than 0.05) and CSF NE concentrations increased from 68 +/- 12 pg.ml-1 to 336 +/- 85 pg.ml-1 in the NE group (P less than 0.01). In the second part, eight patients with herpetic neuralgia received epidural analgesia at the fourth to eighth thoracic interspace, using bupivacaine 0.25 per cent, with and without NE. The CSF NE concentrations in this group were greater than in the surgical patients before operation and increased from 254 +/- 58 to 406 +/- 58 pg.ml-1 30 min after administration of bupivacaine with NE. The duration of pain relief was prolonged with NE. These results suggest that adding NE to local anaesthetics prolongs epidural analgesia. Moreover, NE concentrations in surgical patients increased to levels similar to those found in patients suffering from herpetic analgesia. This suggests that the increase of CSF NE in chronic pain states has an antinociceptive effect.  相似文献   
967.
Distribution of nitric oxide synthase in intracardiac ganglion cells located in human, monkey and canine right atria was histologically investigated using the reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase method and acetylcholinesterase histochemistry. In the intracardiac ganglion, many large neurons exhibited both positive reactions, whereas some of the NADPH diaphorase-positive small neuronal cells were shown with negative acetylcholinesterase reaction.  相似文献   
968.
Our objective was to assess the effects of subtle increasesin serum progesterone concentration (1.0–2.0 ng/ml) onthe outcome of in-vitro fertilization (IVF), particularly onthe quality of embryos, during the follicular phase of cyclesstimulated with gonadotrophin-releasing hormone agonist (GnRHa)and human menopausal gonadotrophin (HMG). A total of 97 patientsunderwent 116 cycles of IVF and were stimulated with a combinationof HMG and GnRHa. They were divided into two groups: those witha subtle progesterone rise and those with no progesterone rise.The two groups were compared with respect to serum oestradiol,progesterone, immunoreactive luteinizing hormone (I-LH), bioactiveLH (B-LH), and results of IVF. The groups did not differ significantlyin mean age or in total dose of HMG received. On the day thathuman chorionic gonadotrophin was administered, concentrationsof oestradiol and progesterone were significantly higher inthe subtle progesterone rise cycles than in the no progesteronerise cycles. In the no progesterone rise cycles, the percentagesfor embryos beyond the 4-cell stage, grade 1 embryos, and implantationrates were significantly higher than those in subtle progesteronerise cycles. The combination of GnRHa and HMG eliminated anysignificant rise in serum I-LH or B-LH concentration duringthe follicular phase, but did not suppress the subtle rise inprogesterone. These results confirm our previous finding thata subtle progesterone rise adversely affects the outcome ofIVF. It is also suggested that a reduction in embryo qualitymay influence the lower rate of implantation in subtle progesteronerise cycles.  相似文献   
969.
In order to evaluate the effectiveness and safety of ultrasonic oocyte collection for IVF-ET, a comparative study was performed on the results of IVF-ET by the transabdominal and transvaginal methods in 145 cycles of 51 patients. The oocyte collection rate for the transvaginal method was significantly higher than that for the transabdominal method (77.1% vs. 68.7% per follicle, p less than 0.01). The majority of the oocytes were collected in three follicular flushings. The fertilization rate for oocytes collected by the transabdominal method was significantly higher than that for those collected by the transvaginal method in cases of tubal damage and endometriosis (81.1% vs. 65.6% per oocyte, p less than 0.01). There was no significant difference between the signs of complications seen with the two methods. Six successful pregnancies were obtained by IVF-ET in our hospital (4 cases by the transabdominal method, and 2 cases by the transvaginal method). Two of these cases have already delivered full term healthy male infants. In conclusion, these results indicate that ultrasonic oocyte collection has been established as the most effective method for IVF-ET by means of either the transabdominal or the transvaginal methods.  相似文献   
970.
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