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171.
172.
The aim of the study is to investigate the relationship between DNA histogram and radiosensitivity on tumor specimens taken directly from patients. Flow cytometric DNA content analysis with PI (Propidium iodide) was performed on specimens of cervical carcinoma. Radiosensitivities of respective tumors were determined on biopsy specimens that were taken 3 weeks after the start of radiotherapy. Five parameters (over 4C, %G2M, %S, PI, DI) were calculated from DNA Histogram. Among these parameters over 4C, %G2M and PI correlated well to radiosensitivity.  相似文献   
173.
The physiologic effects of pulsatile and non-pulsatile flow in cardiopulmonary bypass were compared in terms of the relationship between different flow rates and what effects these had on pulsatile and non-pulsatile flow. Forty adult mongrel dogs were used in this study and divided into 5 groups, each comprised of 8 animals, according to the flow rate during cardiopulmonary bypass, namely; 40, 60, 80, 100, or 120 ml/kg/min. The animals were perfused with either pulsatile or non-pulsatile flow for 1 hour, given randomly at the same mean flow rate. At flow rates of 80 and 100 ml/kg/min, the mean arterial blood pressure and total peripheral vascular resistance were significantly lower in pulsatile flow than in non-pulsatile flow, and the renal blood flow was significantly greater in pulsatile flow than in non-pulsatile flow. The renal arterial-venous lactate difference was significantly less in pulsatile flow than in non-pulsatile flow at a flow rate of 80 ml/kg/min, and the renal lactate extraction was significantly higher in pulsatile flow than in non-pulsatile flow at the same flow rate. The renal excess lactate was significantly lower in pulsatile flow than in non-pulsatile flow at a flow rate of 100 ml/kg/min. There were no significant differences in these parameters between the two types of perfusion at flow rates of 40, 60 or 120 ml/kg/min. Pulsatile flow was therefore apparently advantageous, when compared to non-pulsatile flow, in terms of hemodynamics, renal circulation, and metabolism of the kidney at flow rates of 80 and 100 ml/kg/min. However, when the flow rate was 120 ml/kg/min, pulsatile flow and non-pulsatile flow had the same effects.  相似文献   
174.
Abstract— The dynamics of insulin absorption from the ocular conjunctiva of anaesthetized normal and pancreatectomized dogs have been examined. A porcine insulin preparation of 1000 units mL?1 (pH 8.0) was administered as either 1 or 10 units kg?1 to the upper conjunctival sacs of recumbent dogs following an overnight fast. Plasma insulin concentrations increased significantly at 5 min after the insulin administration. Plasma glucose concentrations decreased significantly, in both normal (given 10 units kg?1) and diabetic dogs (given 1 unit kg?1 or 10 units kg?1). There was a dose-dependent increase in plasma insulin concentration following conjunctival administration. Estimated absorption was significantly higher in diabetic than in normal dogs.  相似文献   
175.
Microvascular decompression procedures were carried out to relieve right hemifacial spasm in a 54-year-old man. His facial spasm was satisfactorily cured but he complained of severe vertigo, and slight facial palsy was also shown after the operation. Electronystagmograph disclosed spontaneous horizontal and rotatory nystagmus toward the non-operated (left) side. The postoperative caloric test showed profound dysfunction on the operated side. His hearing was well maintained postoperatively. These findings indicated, in addition to facial nerve injury, that the peripheral portion of the vestibular nerve was selectively damaged by the operative manipulations. It was shown that both the facial and vestibular nerves tended to be injured when the nerve trunk was shifted caudal-to-rostrally due to manipulations in the CP angle. It was stressed that caution should be paid to preserve not only the cochlear but also the vestibular nerve function in cerebellopontine angle manipulations.  相似文献   
176.
177.
The distribution of melanin-concentrating hormone-like immunoreactivity was investigated by radioimmunoassay in the CNS of rat, guinea-pig, pig and man. Highest concentrations of melanin-concentrating hormone-like immunoreactivity were found in the hypothalamus of all the species: rat 204.4 +/- 14.9; guinea-pig 159.5 +/- 23.3; pig 10.9 +/- 4.5 and man 80.1 +/- 19.1 pmol/g. Gel chromatographic analysis of hypothalamic extracts showed five immunoreactive peaks of melanin-concentrating hormone-like immunoreactivity in the rat and pig and six in the guinea-pig and man. High-performance liquid chromatography analysis of hypothalamic extracts showed five immunoreactive peaks in rat, guinea-pig, pig and four in man. However, these peaks appeared at different retention times from that of the single peak of salmon melanin-concentrating hormone. Examination of subcellular fractions of whole rat brain showed that most of the melanin-concentrating hormone-like immunoreactivity is found in the synaptosome fraction. Stimulation of melanin-concentrating hormone-like immunoreactivity release from rat hypothalamic slices revealed that potassium in the presence of calcium stimulated melanin-concentrating hormone-like immunoreactivity release. These findings suggest that mammalian melanin-concentrating hormone-like immunoreactivity has a different amino acid sequence from salmon melanin-concentrating hormone and may exist in multiple molecular forms. It is possible that melanin-concentrating hormone may play a role as a neurotransmitter or modulator in the mammalian CNS.  相似文献   
178.
Twenty patients with left ventricular aneurysms were studied by left ventricular angiography and computed tomography. Measurements of left ventricular short axis, percentage of non-aneurysmal myocardium, and size of aneurysm were determined by both techniques. Qualitative assessments of left ventricular size together with the anatomical relation of the aneurysm to the ventricle were also made. The aneurysm was assessed for resectability by both techniques using these criteria. In all cases there was a distinct and diagnostic change in the contour of the ventricle on computed tomography. Computed tomography indicated eight aneurysms to be unresectable, and this agreed with the angiographic assessment. Of the remaining 12 aneurysms, seven were considered to be resectable on angiography. Computed tomography appears to be a reliable non-invasive technique for identifying left ventricular aneurysms and a useful screening method for identifying unresectable aneurysms.  相似文献   
179.
180.
Effects of practolol, alprenolol and pindolol on blood pressure in the rat were studied. Also effects of these three beta-blocking agents on blood pressure and heart rate in spinal rats during adrenaline infusion were studied and compared with those of propranolol. The beta-blocking agents produced a sustained pressor action in the rat, and in the spinal rat infused with adrenaline. The magnitude of the pressor action induced by the beta-blockers was in the following order: pindolol larger than or equal to propranolol larger than or equal to alprenolol greater than practolol. Minimum doses of these beta-blockers required to cause a pressor action in the spinal rat infused with adrenaline were in the following order; practolol greater than alprenolol larger than or equal to propranolol larger than or equal to pindolol. The magnitude of the pressor action produced by the same dose of these beta-blockers and minimum doses of these beta-blockers required to cause a pressor action in the spinal rat infused with adrenaline seemed to be roughly proportional to their beta-receptor blocking activities. It was concluded that the minimum doses of these beta-blockers required to cause a pressor action and the magnitude of the pressor action induced by the beta-blockers in the spinal rat infused with adrenaline could be used to compare their beta-blocking activities and that practolol, a cardioselective beta-blocker, seems to block not only cardiac beta-receptor but to some extent also peripheral vascular beta-receptors.  相似文献   
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