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991.
Neonatal treatment with angiotensin-converting enzyme (ACE) inhibitors or the angiotensin II type-1 receptor antagonist losartan in rats induces irreversible renal histological abnormalities, mainly papillary atrophy, in association with an impairment in urinary concentrating ability. The aim of the present study was to assess proximal tubular function in adult rats treated neonatally with enalapril. Male Wistar rats received daily, intraperitoneal injections of either enalapril (10 mg kg?1) or isotonic saline vehicle from 3 to 24 days of age. In 15-week-old, hydropenic rats we analysed: (i) proximal tubular iso-osmotic fluid reabsorption using the method of lithium clearance; and (ii) maximal tubular D -glucose reabsorption (TmG), under pentobarbital anaesthesia. The main findings were that neonatally enalapril-treated rats showed: (i) reductions in absolute (APRH2O) and fractional (FPRH2O) iso-osmotic fluid reabsorption in the proximal tubules (APRH2O: 0.50 ± 0.02 vs. 0.64 ± 0.03 mL min?1 g KW?1, P < 0.05; FPRH2O: 58 ± 3 vs. 68 ± 2%, P < 0.05); and (ii) a normal TmG. In addition, during baseline clearance measurements neonatally enalapril-treated rats showed increases in urine volume and fractional excretion rates of sodium and potassium, a reduction in urine osmolality, whereas glomerular filtration rate and effective renal plasma flow were unaltered. These results suggest that neonatal ACE inhibition produces an irreversible, but differentiated, abnormality in proximal tubular function. Thus, the development of a normal proximal tubular function in the rat seems to be dependent on an intact renin-angiotensin system, (RAS) neonatally. 相似文献
992.
993.
Physiological and Psychological Effects of Delivering Medical News Using a Simulated Physician–Patient Scenario 总被引:1,自引:0,他引:1
Cohen L Baile WF Henninger E Agarwal SK Kudelka AP Lenzi R Sterner J Marshall GD 《Journal of behavioral medicine》2003,26(5):459-471
We examined the acute stress response associated with having to deliver either bad or good medical news using a simulated physician–patient scenario. Twenty-five healthy medical students were randomly assigned to a bad medical news (BN), a good medical news (GN), or a control group that read magazines during the session. Self-report measures were obtained before and after the task. Blood pressure and heart rate were measured throughout the task period. Four blood samples were obtained across the task period. The BN and GN tasks produced significant increases in self-reported distress and cardiovascular responses compared with the control group. There was also a significant increase in natural killer cell function 10 min into the task in the BN group compared with the control group. The BN task was also somewhat more stressful than the GN task, as shown by the self-report and cardiovascular data. These findings suggest that a simulated physician–patient scenario produces an acute stress response in the physician, with the delivery of bad medical news more stressful than the delivery of good medical news. 相似文献
994.
A decline of the Callimico goeldii population in American zoos is presently occurring due to glomerulonephritis of unknown etiology. We hypothesized that this emerging idiopathic fatal renal disease (IFRD) was caused by a virus. We therefore attempted to isolate virus from the kidneys three C. goeldi in Illinois that had IFRD. Along with other viruses, Simian virus 40 (SV-40) strain CAL was isolated. SV-40-CAL is currently the slowest-growing natural isolate of SV-40 in CV-1 cells. Inefficient SV-40-CAL growth in CV-1 cells stems from two features: a suboptimal protoarchetypal regulatory region, and a Large tumor antigen gene sequence like that of SV-40 strain T302, previously considered the slow-growing natural isolate of SV-40. To our knowledge, this is the first documented isolation of SV-40 from a New World monkey outside of a laboratory setting. Though SV-40 is renaltropic, the role of SV-40-CAL in IFRD is uncertain. Transmission of SV-40 to C. goeldii through anthropogenic activity is suspected. 相似文献
995.
At older ages, the circadian rhythm of body temperature shows a decreased amplitude, an advanced phase, and decreased stability. The present review evaluates to what extent these changes may result from age-related deficiencies at several levels of the thermoregulatory system, including thermoreception, thermogenesis and conservation, heat loss, and central regulation. Whereas some changes are related to the aging process per se, others appear to be secondary to other factors, for which the risk increases with aging, notably a decreased level of fitness and physical activity. Moreover, functional implications of the body temperature rhythm are discussed. For example, the relation between circadian rhythm and thermoregulation has hardly been investigated, while evidence showed that sleep quality is dependent on both aspects. It is proposed that the circadian rhythm in temperature in homeotherms should not be regarded as a leftover of ectothermy in early evolution, but appears to be of functional significance for physiology from the level of molecules to cognition. A new view on the functional significance of the circadian rhythm in peripheral vasodilation and the consequent out-of-phase rhythms in skin and core temperature is presented. It is unlikely that the strong, daily occurring, peripheral vasodilation primarily represents heat loss in response to a lowering of set point, since behavioral measures are simultaneously taken in order to prevent heat loss. Several indications rather point towards a supportive role in immunological host defense mechanisms. Given the functional significance of the temperature rhythm, research should focus on the feasibility and effectiveness of methods that can in principle be applied in order to enhance the weakened circadian temperature rhythm in the elderly. 相似文献
996.
Effekte einer Captopriltherapie auf die Natrium- und Wasserausscheidung bei Patienten mit Leberzirrhose und Aszites 总被引:1,自引:0,他引:1
R. Brunkhorst E. Wrenger K. Kühn F. W. Schmidt K. Koch 《Journal of molecular medicine (Berlin, Germany)》1989,67(15):774-783
Summary Ascites in patients with cirrhosis of the liver frequently is refractory to diuretic treatment. It was postulated that vasoconstriction of the renal cortex, mediated by activation of the renin-angiotensin-aldosterone-system (RAAS), may be one course of the disturbed sodium- and water-excretion in these patients. We therefore investigated in 14 cirrhotic patients with ascites under constant diuretic treatment the effects of low-dose captopril therapy on urinary sodium- and potassium-excretion, body weight, abdominal girth, serum-sodium,-potassium, creatinine-clearance, plasma-renin-activity (PRA), plasma-aldosterone (PA) and mean arterial pressure (MAP). After a control period of 4 days the patients received 2 × 6.25 mg/d captopril for 5 days and 4 × 6.25 mg/d for further 5 days. Treatment was followed by a second control period without captopril.PRA increased significantly after 2 days of captopril treatment. 2 × 6.25 mg/d captopril induced a significant increase in sodium excretion and a significant decrease of body weight. MAP decreased slightly but significantly without clinical signs of hypotension. 4 × 6.25 mg/d captopril resulted in a further reduction of body weight and a further enhancement of sodium excretion. Three days after withdrawal of captopril sodium output was significantly reduced again. Conclusion: In cirrhotic patients low-dose captopril seems to be efficient in the treatment of ascites resistant to diuretics without causing major side effects.
Abkürzungen ACE Angiotensin-Converting-Enzym - A-II Angiotensin II - CH 2 O Frei-Wasser-Clearance - CKrea Kreatinin-Clearance - COsmo Osmolale Clearance - g Gramm - h Stunde - kg Kilogramm - l/d Liter pro Tag - MAP Mittlerer arterieller Blutdruck - mg Milligramm - mg/d Milligramm pro Tag - ml/min Milliliter pro Minute - mmHg Millimeter Quecksilbersäule (Torr) - mmol/d Millimol pro Tag - NaCl Natriumchlorid - ng/ml/h Nanogramm pro Milliliter und Stunde - PA Plasma-Aldosteron - pg/ml Picogramm pro Milliliter - PRA Plasma-Renin-Aktivität - RAAS Renin-Angiotensin-Aldosteron-System - SEM Standardfehler des Mittelwertes - SKrea Kreatininkonzentration im Serum - SOsm Serum-Osmolalität - UKrea Kreatininkonzentration im Urin - UOsm Urin-Osmolalität - V Urinminutenvolumen - vgl. vergleiche - µmol/l Micromol pro Liter 相似文献
Abkürzungen ACE Angiotensin-Converting-Enzym - A-II Angiotensin II - CH 2 O Frei-Wasser-Clearance - CKrea Kreatinin-Clearance - COsmo Osmolale Clearance - g Gramm - h Stunde - kg Kilogramm - l/d Liter pro Tag - MAP Mittlerer arterieller Blutdruck - mg Milligramm - mg/d Milligramm pro Tag - ml/min Milliliter pro Minute - mmHg Millimeter Quecksilbersäule (Torr) - mmol/d Millimol pro Tag - NaCl Natriumchlorid - ng/ml/h Nanogramm pro Milliliter und Stunde - PA Plasma-Aldosteron - pg/ml Picogramm pro Milliliter - PRA Plasma-Renin-Aktivität - RAAS Renin-Angiotensin-Aldosteron-System - SEM Standardfehler des Mittelwertes - SKrea Kreatininkonzentration im Serum - SOsm Serum-Osmolalität - UKrea Kreatininkonzentration im Urin - UOsm Urin-Osmolalität - V Urinminutenvolumen - vgl. vergleiche - µmol/l Micromol pro Liter 相似文献
997.
评价新型的双极和三极导管自动心室除颤系统电除颤对左心室收缩和舒张功能的影响。动物麻醉后,在X光机指导下,分别在10只犬心脏内装置双极导管自动除颤系统(组Ⅰ);在10只猪心脏内装置三极导管自动除颤系统(组Ⅱ);并行电除颤试验。使用食管超声心动图在电除颤前后记录二维、M型和多谱勒超声图像。组I动物接受4次电除颤,电量为64J;组Ⅱ接受平均8次电除颤,电量为210J。结果显示:左室收缩面积分数、左室等容舒张时间和二尖瓣血流E波与A波速度比值以及时间-流速积分比值等反映左室舒缩功能的指标在两组动物除颤后均无显著改变。研究表明:两种经静脉导管自动心室除颤系统中反复低能量心内膜电除颤对左室舒缩功能无明显损伤作用;研究结果为经静脉多极导管自动心室除颤系统在临床的应用和电生理研究提供了可靠的实验数据。 相似文献
998.
Bilateral salpingectomy does not compromise ovarian stimulation in an in-vitro fertilization/embryo transfer programme 总被引:9,自引:5,他引:9
Verhulst Guy; Vandersteen Nadia; Van Steirteghem Andre C.; Devroey Paul 《Human reproduction (Oxford, England)》1994,9(4):624-628
The question whether salpingectomy has a negative influenceon ovarian function and the outcome of pregnancy in an in-vitrofertilization (IVF) and embryo transfer treatment programmeis not yet answered. We performed a retrospective case-controlstudy to investigate the possible negative effect of salpingectomyon ovarian response to human menopausal gonadotrophins (HMG)during IVF and embryo transfer. The study group was composedof 26 patients with bilateral salpingectomy. In 67 cycles weanalysed different parameters of ovulation such as the numberof days of ovarian stimulation, numbers of ampoules of HMG,pre-ovulatory oestradiol concentrations and the numbers of oocytesretrieved. These parameters were compared to a control groupof 134 cycles in 134 women with healthy Fallopian tubes. Nodifferences were found. Implantation ratio, pregnancy rate andoutcome were the same in both groups. We conclude that bilateralsalpingectomy had no detrimental effect on ovarian performanceduring IVF and embryo transfer treatment nor on the outcome. 相似文献
999.
1000.
目的 探讨盐酸多奈哌齐对轻、中型脑外伤患者认知障碍及临床预后的影响。方法 78例轻、中型脑外伤并认知障碍患者被随机分成治疗组和对照组,治疗组应用盐酸多奈哌齐10mg/d,对照组应用吡拉西坦8mg,一日3次服用,两组的治疗周期为12周。治疗前及治疗后12周,分别应用简明精神状态检测量表(MMSE)、国人修订成人韦氏智利量表(WAIS-RC)和格拉斯哥预后评分(GOS)评价疗效。结果 两组在治疗后12周,MMSE和WAIS-RC评分均较治疗前提高(P〈0.05)。治疗后12周,治疗组MMSE和WAIS-RC评分较对照组高(P〈0.05),治疗组GOS预后优良率明显优于对照组(P〈0.05)。结论 盐酸多奈哌齐对轻、中型脑外伤后认知障碍有积极治疗作用,并能改善临床预后。 相似文献