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231.
This double-masked, placebo-controlled study was undertaken to determine the efficacy and safety of oral clodronate in the prevention of bone loss in early postmenopausal women with vertebral osteopenia. Altogether 610 women with a mean age of 53 years were recruited for the study. They were 1–5 years postmenopausal and their lumbar spine bone mineral density (BMD) was at least 1 standard deviation below the mean of premenopausal women (T-score ≤−1). The subjects were randomized into five study groups to receive either placebo, clodronate 65 mg, 400 mg or 800 mg daily, or intermittent clodronate in 3 month cycles with 400 mg daily for 15 days followed with no treatment for 75 days for 3 years. One hundred and eighty-seven of 509 women who completed the primary study continued in the extension study of 2 years in which previous placebo users were switched to clodronate 800 mg daily, while previous users of 400 mg or 800 mg of clodronate used either placebo or 800 mg of clodronate daily. In the primary study clodronate was administered in the evening, and in the extension 1 h before breakfast on an empty stomach. In the primary study mean changes in lumbar spine BMD were −3.4% in the placebo group and +0.4% in 800 mg clodronate group [difference between groups at 3 years 3.8% (95% CI 2.7% to 4.9%, p<0.0001)], and in the trochanter area BMD −1.1% in the placebo group, and + 0.4% in the 800 mg clodronate group [difference between groups at 3 years 1.5% (95% CI 0.05% to 2.9%)]. During the extension study mean changes in lumbar spine BMD were +1.5% in the clodronate group and −0.2 % in the placebo group [difference between groups 1.7% (CI 0.4% to 3.0%, p = 0.010)] and in trochanter BMD were +2.5% in the clodronate group and no change in the placebo group [difference between groups 2.1% (CI 0.3% to 3.9%, p = 0.007)]. No statistically significant differences between the placebo and 800 mg clodronate groups were found in the femoral neck BMD. In the primary study the urinary excretion of type I collagen aminoterminal telopeptide (NTX) decreased by 44% (p<0.0001 compared with placebo) and that of deoxypyridinoline by 18% (p<0.0001) in the clodronate 800 mg group. In the extension study urinary NTX decreased by 51% (p<0.0001) in those who were switched to 800 mg of clodronate and increased by 67% (p<0.0001) in those who stopped using that dose. There was no difference in the frequency of gastrointestinal complaints between clodronate- and placebo-treated patients in the primary study, but they were more common among women who received clodronate in the extension phase. Clodronate in daily doses of 400–800 mg caused a slight elevation of aminotransferase levels, usually within the reference range. In bone biopsies no defect in mineralization was found. In conclusion, clodronate in a daily dose of 800 mg prevents early postmenopausal bone loss at the sites of the skeleton in which cancellous bone predominates. It effectively reduces bone resorption and bone turnover rate. Antifracture efficacy of clodronate remains to be established by prospective, placebo-controlled trials. Received: 4 March 2002 / Accepted: 9 July 2002  相似文献   
232.
Deep venous thrombosis and pulmonary embolism   总被引:2,自引:0,他引:2  
All surgical patients are at risk for the development of deep venous thrombosis and subsequent pulmonary embolism or postphlebitic syndrome. The evolution of ultrasonographic imaging has increased the awareness of prevention, diagnosis, and treatment of deep venous thrombosis. Duplex imaging and Doppler color flow imaging have made the diagnosis of deep venous thrombosis relatively simple, painless, inexpensive, and definitive. These procedures have gained acceptance by both patients and physicians. Several risk factors have been identified that increase the chance of the development of deep venous thrombosis. These factors include a history of deep venous thrombosis, presence of a malignant process, increasing age, cigarette smoking, obesity, prolonged bed rest, and general anesthesia. The greater the number of risk factors, the more aggressive prophylaxis should be. Means of prophylaxis have improved, and surgeons now generally agree that some form of prophylaxis is required. Heparin and intermittent compression devices appear to be equally effective in preventing deep venous thrombosis. The addition of venous monitoring in high-risk patients permits immediate identification of the presence of deep venous thrombosis. During the last decade, the treatment of patients with deep venous thrombosis has changed little. Heparin followed by warfarin remains the treatment of choice. A small group of patients receive fibrinolytic therapy for deep venous thrombosis. Although the incidence of postoperative deep venous thrombosis has decreased during the last decade, it remains a significant complication.  相似文献   
233.
This study investigated the potential role of adenosine in cerebral blood flow (CBF) regulation in the neonate during moderate and severe hypotension. Experiments were done in anesthetized, 1- to 3-day-old piglets. Regional CBF (determined by radiolabeled microsphere technique) and cerebral metabolic rate for O2 (CMRO2) were measured (a) during normotension and (b) during a 3-min period of moderate (58 +/- 9 mm Hg) or severe (36 +/- 7 mm Hg) hypotension produced by the inflation of a balloon catheter placed in the aortic root. Measurements of CBF and CMRO2 were performed successively after intracerebroventricular (i.c.v.) injections of vehicle (n = 17), the adenosine receptor blocker 8-phenyltheophylline (8-PT, 10 micrograms, n = 14), and the A2-receptor agonist 5'-N-(ethylcarboxamide)adenosine (NECA, 2 ng, n = 8). After i.c.v. administration of vehicle, none of the parameters studied was significantly altered by moderate hypotension, but severe hypotension decreased the total CBF (mean +/- SD) from 86 +/- 24 to 40 +/- 15 ml min-1 100 g-1 and CMRO2 from 3.2 +/- 0.8 to 1.8 +/- 1.0 ml min-1 100 g-1 (p less than 0.05). Administration of 8-PT did not alter these parameters during normotension, but significantly decreased CBF during moderate hypotension compared to postvehicle values (53 +/- 11 versus 81 +/- 12 ml min-1 100 g-1, p less than 0.05). This loss of autoregulation was completely reversed by NECA. During severe hypotension, 8-PT altered the CBF redistribution towards the brainstem.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
234.
A total of 102 patients were examined, 32 of these with true eczema, 38 with exudative mycosis of the soles, and 32 with eczema etiologically related to a fungal infection. Analysis of the immune and biochemical reactions in the examinees has shown a marked reduction of adenyl nucleotides in the leukocytic suspension and neutrophils of patients with a mycotic infection as against those with true eczema. The lowest creatine phosphate levels were detected in the leukocytic suspension and neutrophils of the patients suffering from eczema etiologically related to mycosis and exudative mycosis of the soles. These results give grounds to search for effective corrective therapy.  相似文献   
235.
This paper discusses the application of intravenous Kalipsol anesthesia in combination with Seduxen (Relanium) in 22 patients who underwent antro-mastoidectomy (expanded) and fronto-ethmoidectomy. No complications related to the method of anesthesia were identified. It is concluded that the use of Kalipsol anesthesia in urgent ENT operations provides better surgical intervention. This method ensures adequate analgesia during operation.  相似文献   
236.
This paper reports the changes in prolactin levels after 12 spontaneous and 52 induced pregnancies in 54 women with unambiguous hyperprolactinaemia (median plasma prolactin levels 67.5 ng/ml, range 40-400). Twenty-three of the patients showed radiological evidence of prolactinoma. The pregnancies were induced in 37 patients by bromocriptine, in nine by metergoline, in two by lisuride and in four by other treatments. Of the 64 pregnancies, 16 ended in spontaneous abortion, while 48 went to term. Follow-up was continued for at least 6 months after delivery or until the end of lactation. In a control group of 32 hyperprolactinaemic women (median prolactin 70 ng/ml, range 40-400) not wishing to become pregnant, prolactin changes were similarly registered over a mean period of 15 months without any treatment (range 6-38 months). After pregnancy, a significant downward trend of plasma prolactin was observed in the puerperal women with a 'normalization' rate of 17%. No changes were observed in the 32 controls who did not become pregnant.  相似文献   
237.
Department of Biology, Izhevsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR D. S. Sarkisov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 107, No. 3, pp. 353–356, March, 1989.  相似文献   
238.
239.
Endogenous opioids are present in neurons of the vagus and the intrinsic nervous system and they are colocalized with gastrin in antral G-cells. This raises the possibility that endogenous opioids modulate gastrin release. Stimulation of both cervical vagi (10V, 5Hz, 5ms) elicited an increase of arterial plasma gastrin levels at intragastric pH7 or pH2. The response at pH2 was 30% of that at luminal pH7. Atropine reduced vagally stimulated gastrin levels substantially. At luminal pH2 the small residual noncholinergic response was mediated neither by adrenergic mechanisms nor by endogenous opioids. At luminal pH 7 adrenergic blockade with phentolamine and propranolol reduced vagally stimulated gastrin by 60%. In the presence of atropine adrenergic blockade elicited only a small inhibitory effect suggesting that vagal activation of adrenergic mechanisms depends on atropine-sensitive cholinergic pathways. Blockade of opiate receptors by naloxone had no effect on vagal gastrin release, however, the noncholinergic gastrin response was reduced significantly by naloxone, suggesting that cholinergic mechanisms normally restrain activation of endogenous opioids during vagal stimulation. Naloxone had no effect on the noncholinergic, nonadrenergic stimulation of gastrin levels. These data suggest that endogenous opioids can contribute to vagal gastrin release provided the cholinergic restraint is blocked and adrenergic mechanisms stimulate endogenous opioids. In conclusion a major role of endogenous opioids in the regulation of vagal gastrin release can not be detected.  相似文献   
240.
The oncocytic Schneiderian papilloma (OSP) is a rare neoplasm of the nose and paranasal sinuses. The majority of the approximately twenty patients reported in the literature with this papilloma have been over the age of fifty at the time of diagnosis. The 33-year-old woman reported here is the youngest patient with this lesion to date. The OSP should be considered in the work-up of all unilateral nasal polypoid lesions. This lesion's propensity for recurrence and its documented association with synchronous malignant disease warrant surgical excision by en bloc resection of the lateral nasal wall, with corresponding careful microscopic evaluation of all excised tissue.  相似文献   
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