首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   8552篇
  免费   420篇
  国内免费   45篇
耳鼻咽喉   55篇
儿科学   142篇
妇产科学   259篇
基础医学   1042篇
口腔科学   154篇
临床医学   566篇
内科学   2209篇
皮肤病学   448篇
神经病学   495篇
特种医学   258篇
外科学   1361篇
综合类   25篇
预防医学   191篇
眼科学   187篇
药学   556篇
中国医学   17篇
肿瘤学   1052篇
  2023年   47篇
  2022年   93篇
  2021年   142篇
  2020年   101篇
  2019年   124篇
  2018年   184篇
  2017年   123篇
  2016年   158篇
  2015年   151篇
  2014年   209篇
  2013年   222篇
  2012年   353篇
  2011年   389篇
  2010年   246篇
  2009年   202篇
  2008年   377篇
  2007年   433篇
  2006年   415篇
  2005年   424篇
  2004年   408篇
  2003年   359篇
  2002年   393篇
  2001年   298篇
  2000年   257篇
  1999年   294篇
  1998年   135篇
  1997年   92篇
  1996年   95篇
  1995年   87篇
  1994年   52篇
  1993年   53篇
  1992年   171篇
  1991年   190篇
  1990年   177篇
  1989年   206篇
  1988年   179篇
  1987年   166篇
  1986年   131篇
  1985年   129篇
  1984年   84篇
  1983年   83篇
  1982年   33篇
  1980年   36篇
  1979年   56篇
  1978年   37篇
  1977年   40篇
  1974年   41篇
  1972年   36篇
  1971年   36篇
  1969年   41篇
排序方式: 共有9017条查询结果,搜索用时 27 毫秒
101.
We previously demonstrated that intraperitoneal hyperthermic perfusion (IPHP), which is performed clinically as a treatment for patients with advanced gastrointestinal cancer, can lead to increased serum tumor necrosis factor-alpha (TNF-alpha), systemic inflammatory response syndrome (SIRS), and acute lung injury. Glucocorticoids inhibit the production and actions of TNF-alpha. We investigated whether pretreatment with methylprednisolone (MPS) may modulate serum TNF-alpha and lung injury in patients subjected to IPHP. Serum TNF-alpha was not detected in the patients pretreated with MPS, whereas serum TNF-alpha increased in the control patients (45.7 +/- 8.3 pg/mL, mean +/- SEM) after IPHP. Postoperative lung injury scores were significantly lower in patients pretreated with MPS than in the control patients (P < 0.001). Implications: Pretreatment with methylprednisolone attenuates the increase in circulating tumor necrosis factor-alpha and prevents lung injury in this systemic inflammatory syndrome due to intraperitoneal hyperthermic perfusion.  相似文献   
102.
The electrocardiogram (ECG) is used as a standard monitoring method during anesthesia and operation. But during the operation of severely burnt patients, the electrodes for ECG cannot be placed on the ideal points for the standard limb leads. We tried the indirect monitoring of the ECG. We placed the electrodes on the sheet over the operating table, and connected the patient and the electrodes with water. By this way the ECG similar to the standard limb leads could be recorded. This method is useful for the patients, with such diseases as severe burn, severe atopic dermatitis and epidermolysis bullosa hereditaria.  相似文献   
103.
104.
We report herein an unusual case of primary malignant fibrous histiocytoma (MFH) of the ascending colon. A 47-year-old man was admitted to our hospital for further investigations following the discovery of a mass in the right lower quadrant of the abdomen during a medical checkup. Abdominal ultrasonography (US) and computed tomography (CT) demonstrated a mass extending to the right lateral side from the ascending colon. At laparotomy, a tumor was found originating in the ascending colon and infiltrating the right lateral peritoneum. A right hemicolectomy and partial peritoneal dissection were performed followed by an ileotransverse colostomy reconstruction. The resected specimen contained a tumor measuring 7×5×4 cm, the cut surface of which was yellowish white, and the mucosa of the colon was intact. Based on histological and immunohistochemical inspection, the tumor was diagnosed as MFH of the ascending colon. We reviewed the total 18 known cases of colorectal MFH documented in the literature including our case. After surgery, 4 of 17 patients died of local recurrence, all within 42 months, indicating that early and complete excision of tumor is essential to achieve cure.  相似文献   
105.
Axonal and glial reactions to traumatic injury were compared between the caudal and rostral border of the lesion after freeze-injury to the C3 dorsal funiculus by attaching a liquid nitrogen-cooled copper probe to the dorsum of the rat spinal cord. The axonal and glial changes were examined up to 60 days postoperative by light and electron microscopy and immunohistochemistry for neurofilaments. Regenerative axonal changes and the appearance of numerous undifferentiated cells were found at the caudal border 7 days after cryoinjury. In contrast, such axonal and cellular reactions were scarce at the rostral border. Undifferentiated cells clearly manifested their phenotypes by differentiating into oligodendrocytes or astrocytes 11 days postinjury. The results indicated that glial cell reactions occurred in association with regenerative axonal changes at the proximal stump of the injured nerve fibers, suggesting that regenerating and demyelinated naked axons could be responsible for the appearance of the immature glial cells.  相似文献   
106.
The levels of interleukin-12 (IL-12) (p70 heterodimer), total IL-12 (p70 heterodimer plus p40 chains), interferon-gamma (IFN-gamma) as Th1 cytokine, and those of interleukin-4 (IL-4) and interleukin-10 (IL-10) as Th2 cytokines in sera and cerebrospinal fluid (CSF) from 22 patients with human T lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) were compared with those of 22 patients with other neurological diseases (OND), including nine anti-HTLV-I-seropositive carriers. Both serum IL-12 (total and p70 heterodimer) and CSF IFN-gamma, measured by the enzyme-linked immunosorbent assay (ELISA), were significantly elevated in patients with HAM as compared to the patients with OND, including the anti-HTLV-I-seropositive carriers. Serum IFN-gamma also was significantly elevated in the HAM patients as compared to the controls. There was no significant difference in the CSF levels of IL-12 (total and p70 heterodimer) between the HAM patients and controls, whereas, for the Th2 cytokines IL-4 was detected in the CSF of four anti-HTLV-I-seropositive carriers of the 13 control patients but not in any of the patients with HAM. No significant difference was found in the serum levels of IL-4 and IL-10, nor in the CSF levels of IL-10 in the patients with HAM and in the controls. These findings indicate that in patients with HAM, the immunological balance of helper T lymphocytes between Th1 and Th2 is toward Th1 in the periphery and that Th1-mediated immunological status in the central nervous system is involved in the pathogenesis of HAM.  相似文献   
107.
Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma.  相似文献   
108.
This study sought to assess the prevalence and symptomatology of comorbid obsessive-compulsive disorder (OCD) among Japanese subjects who met the DSM-III-R criteria for bulimia nervosa (BN). The Structured Clinical Interview for DSM-III-R Patient Version was used to distinguish 26 BN patients with concurrent OCD from 52 BN patients without OCD. Obsessive-compulsive symptoms in BN subjects with concurrent OCD were evaluated using the Japanese version of the Yale-Brown Obsessive-Compulsive Scale. There were no differences in the prevalence of concurrent OCD between BN subjects with and without a lifetime history of anorexia nervosa. Among BN subjects with concurrent OCD, symptoms related to symmetry and order were most frequently identified, followed by contamination and aggressive obsessions, and checking and cleaning/washing compulsions. Bulimia nervosa subjects with concurrent OCD were more likely than subjects without OCD to have more severe mood and core eating disorder psychopathology. Comorbid OCD is a common phenomenon in Japanese bulimics (33%) similar to that suggested in BN subjects in the Western countries. Obsessive-compulsive symptoms related to symmetry and order were most frequently observed in BN subjects with concurrent OCD, which was a similar finding to that reported among restricting anorexic subjects.  相似文献   
109.
Horie S  Tobisu KI  Fujimoto H  Doi N  Kakizoe T 《Urology》1999,53(3):561-567
OBJECTIVES: The impact of non-nerve-sparing retropubic radical prostatectomy (RRP) for prostate cancer combined with neoadjuvant androgen deprivation on urinary control is not well documented. We examined the incidence and severity of urinary incontinence after such therapy and determined the etiologic factors causing this complication. METHODS: We examined the postoperative continence status of 104 consecutive patients admitted to the National Cancer Center Hospital who underwent RRP with wide resection of the pelvic nerves after neoadjuvant androgen deprivation. Incontinence was scored according to the number of pads used daily by the patient for urinary leakage. The severity of incontinence was analyzed according to patient age, weight of resected specimen, status of cancer stage, duration of neoadjuvant androgen blockade therapy, preoperative length of membranous urethra, and duration of urethral catheterization after surgery. We also measured the configuration and diameter of the reconstructed bladder neck by retrograde cystourethrography. RESULTS: In 104 patients examined, the percentage of patients who became dry postoperatively was 22% at 1 month, 47% at 3 months, 69% at 6 months, and 78% at 1 year. Of 81 patients who became dry postoperatively at any interval, 22 (27%) became continent within 1 month of RRP, 49 (61 %) were continent within 3 months, 71 (88%) became continent by 6 months, and another 10 (12%) became continent between 6 and 12 months postoperatively. Of 48 patients who were followed up for more than 1 year and for whom continence status at 1 month after surgery was available, all patients who used 1 to 2 pads per day (13 of 13) at 1 month after surgery regained continence by 1 year after surgery. However, only 62% of patients (16 of 26) who required more than 3 pads per day at 1 month after surgery became dry by 1 year after surgery. Only age (older than 70 years) and large prostate size (weight of surgical specimen more than 40 g) temporarily influenced the recovery of urinary continence after surgery. Dilation of the bladder neck evaluated by retrograde cystourethrography was prominent in severely incontinent patients in the immediate postoperative period. CONCLUSIONS: Our experience in patients who undergo non-nerve-sparing RRP after neoadjuvant androgen deprivation closely matches published surveys of patient-reported complications. Postoperative incontinence is not a major contraindication for non-nerve-sparing RRP after neoadjuvant endocrine therapy. Dilation of the bladder neck affected the recovery from incontinence, highlighting the importance of adequate reconstruction of the bladder neck.  相似文献   
110.
Neurofibromatosis Type 1 produces a broad spectrum of clinical manifestations as a result of widespread dysplasia of mesodermal and neuroectodermal tissues. One of the most serious aspects of the disease relates to the arterial involvement that may occur. We report a case of severe stenosis of the internal carotid artery and intracerebral hemorrhage associated with neurofibromatosis Type 1. A 49-year-old female was admitted to our hospital after she had suddenly become comatose. On admission, she demonstrated a decerebrate posture in response to painful stimuli, and was assessed as grade 200 according to the Japan Coma Scale. Physical examination disclosed widespread cutaneous neurofibromas and cafe-au-lait spots. Computed tomography of the head revealed a right putaminal extensive hematoma, with a maximum diameter of 7 cm. The hematoma was removed. After this surgical treatment, cerebral angiography was performed. It showed severe stenosis of the terminal portion of the right internal carotid artery associated with a fine telangiectatic network, indicating the presence of moyamoya vessels in the basal ganglia. Although intracranial hemorrhage associated with neurofibromatosis type 1 is a rare condition, fine telangiectatic collateral vessels caused by occlusive cerebrovascular disease, intracranial aneurysms, brain tumors, or hypertension caused by pheochromocytoma or stenosis of the renal artery should be considered as the cause of hemorrhage.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号