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1.
Chronic venous insufficiency is a debilitating condition. It affects about 0.2% of the population and is very demanding on health resources. In the UK, there are about 100,000 patients with active leg ulcers and treating these patients costs the national health service between £100 and £400,000,000 per anum. This paper reviews the classification, epidemiology, pathophysiology, investigations and treatment of this condition. The etiology of venous ulceration is discussed and the various theories explaining the cause of ulceration examined. The latest research into the condition is reviewed and the relative roles of superficial venous incompetence and deep venous incompetence in the pathophysiology of ulceration is presented. Surgical and non-surgical treatment of the condition including surgical treatment of superficial and deep venous incompetence, compression therapy, and drug therapy is explored.Presented at the 37th Annual World Congress, International College of Angiology, Helsinki, Finland, July 1995.  相似文献   
2.
The purpose of this study was to determine if proliferation of pulmonary alveolar macrophages (PAM) played a significant role in establishing the PAM population of the lung during postnatal development. New Zealand albino rabbits were killed at 0.5, 1 through 5, 7, and 14 days and 4 months after birth and their lungs were lavaged. Cell yield in the lavage was determined by hemocytometer counts, and the percentage of PAM in mitosis (mitotic index) was determined from cytocentrifuge preparations. The total number of PAM increased from 1.5 X 10(6) at 1 day to 8.38 X 10(6) at 14 days after birth. The mitotic index (MI) was 0.6% at 0.5 days after birth, increased to 1.6% at 1 day, and remained elevated through 5 days. By 14 days, the MI declined to 0.2%. The cell cycle time (Ct) of the PAM population was calculated from the MI and ranged from 1.8 to 2.4 days during Days 1 through 5 of life. Direct measurements of the doubling time (Dt) of PAM in the lavage revealed that the PAM population doubled twice over this same time period. Because Ct was equal to Dt during Days 1 through 5, we conclude that proliferation of PAM was the primary mechanism by which the PAM population increased during the immediate postnatal development of the rabbit lung. No evidence was obtained indicating that migratory monocytes or interstitial macrophages were involved with this process of population expansion. This study adds to the growing literature demonstrating that the intraalveolar proliferation of "free" PAM is the major local source of PAM in the lung.  相似文献   
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BACKGROUND & AIMS: Esophagogastroduodenoscopy (EGD) is the current standard for evaluating esophageal varices, yet there is no universally accepted system of grading varices endoscopically and several studies have shown interobserver variability of endoscopic grading. High-resolution endoluminal ultrasound 20 MHz (HRES) has been shown to detect varices accurately and can be performed without sedation. Our aim was to compare the detection of esophageal varices by transnasal HRES and EGD. METHODS: We prospectively studied 37 cirrhotic patients being evaluated for esophageal varices. HRES was used to measure the largest esophageal variceal diameter and then EGD was performed. Photographs were taken for both procedures. Three blinded investigators graded the EGD photographs at 2 periods. End points were as follows: (1) the correlation of HRES variceal diameter and EGD grading of varices, and (2) the assessment of interobserver and intraobserver variation in varix grading by EGD. RESULTS: The correlation between the transnasal HRES and EGD was .63, with a 95% confidence interval of .37-.80. The HRES detected early varices that were not seen by EGD. The interobserver correlation for EGD scoring was .87 or greater in all comparisons and the intraobserver correlation was .91 or greater. CONCLUSIONS: In conclusion, there is a significant correlation between transnasal HRES size measurement of esophageal varices and EGD. HRES is much more sensitive in detecting early esophageal varices and may not require sedation, suggesting that it may be more tolerable to patients and is worth further study.  相似文献   
5.
Shami  PJ; Weinberg  JB 《Blood》1996,87(3):977-982
Nitric oxide (NO) is a reactive molecule with numerous physiologic and pathophysiologic roles affecting the nervous, cardiovascular, and immune systems. In previous work, we have demonstrated that NO inhibits the growth and induces the monocytic differentiation of cells of the HL- 60 cell line. We have also demonstrated that NO inhibits the growth of acute nonlymphocytic leukemia cells freshly isolated from untreated patients and increases monocytic differentiation antigens in some. In the present work, we studied the effect of NO on the growth and differentiation of normal human bone marrow cells in vitro. Mononuclear cells isolated from human bone marrow were cultured in semisolid media and treated with the NO-donating agents sodium nitroprusside (SNP) or S- nitroso-acetyl penicillamine (SNAP) (0.25 to 1 mmol/L). Both agents decreased colony-forming unit-erythroid (CFU-E) and colony-forming unit- granulocyte macrophage (CFU-GM) formation by 34% to 100%. When CD34+ cells were examined, we noted that these cells responded to SNP and SNAP differently than did the mononuclear cells. At a concentration range of 0.25 to 1 mmol/L, SNP inhibited the growth of CFU-E by 30% to 75%. However, at the same concentration range, SNP increased the number of CFU-GM by up to 94%. At concentrations of 0.25 to 1 mmol/L, SNAP inhibited the growth of CFU-E by 33% to 100%. At a concentration of 0.25 mmol/L, SNAP did not affect CFU-GM. At higher concentrations, SNAP inhibited the growth of CFU-GM. Although SNP increased intracellular levels of cGMP in bone marrow cells, increasing cGMP in cells by addition of 8-Br-cGMP (a membrane permeable cGMP analogue) did not reproduce the observed NO effects on bone marrow colonies. These results demonstrate that NO can influence the growth and differentiation of normal human bone marrow cells. NO (generated in the bone marrow microenvironment) may play an important role modulating the growth and differentiation of bone marrow cells in vivo.  相似文献   
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Purpose

Extralevator abdominoperineal excision of the rectum (elAPER) is arguably the modern surgical approach to low rectal cancer and yet results in large defects that may necessitate plastic surgical reconstruction. This study aims to evaluate the quality of prone elAPER surgery with Permacol? repair of the perineum. The primary end point studied was the rate of primary perineal wound healing.

Methods

Data were prospectively collected for consecutive patients having prone elAPER at a single institution to assess surgical morbidity together with pathological and cancer-specific outcomes.

Results

Between 2006 and 2012, 48 patients had prone elAPER with median age of 63 (40–86). Thirty-four patients (72.3 %) received neoadjuvant treatment. Median length of stay was 9 days (6–66). With a prone approach, three patients had specimen perforation (6.4 %) and seven patients had circumferential margin involvement (14.9 %). Complete perineal wound healing was achieved in 34 patients (73.9 %) at 4 weeks. Four patients (8.3 %) were unhealed at 6 months; one patient required a perineal sinus to be laid open, and another patient required plastic surgical reconstruction. No perineal wound herniae have been identified during follow-up.

Conclusions

Acceptable oncological outcomes are achieved with the prone extralevator approach. The technique achieves high rates of primary healing, making it an attractive option in centres without access to plastic reconstructive expertise.  相似文献   
8.
The recent development of direct-acting antiviral (DAA) drugs has revolutionized the area of hepatitis C virus (HCV) therapeutics but the efficacy and clinical outcome of interferon (IFN)-free therapy have not been extensively studied yet. We observed a dramatic increase in hypothyroidism among patients treated with sofosbuvir, IFN, and ribavirin. This is the first prospective study of the thyroid dysfunction in DAA drugs treated patients. This study compared the risk of hypothyroidism in two different groups of HCV patients treated with different DAA drugs regimens that were sofosbuvir + pegylated-IFN-α + ribavirin and sofosbuvir + daclatasvir + ribavirin. Our findings highlight the periodic screening of serum thyroid-stimulating hormone and T4 levels in HCV infected patients during the treatment and posttreatment.  相似文献   
9.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Since its emergence, cholera caused by the bacterium Vibrio cholerae remains as a significant threat to human...  相似文献   
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