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11.
Microdissected pancreatic islets of noninbredob/ob-mice were used to study ionic effects on the lanthanum-nondisplaceable45Ca2+ uptake by islet cells. Omission of Mg2+ from the incubation medium had no effect, but the45Ca2+ uptake was increased by omission of Na+ and decreased by omission of K+. Excess Mg2+ (1.2–15 mM) inhibited and excess K+ (4.7–25 mM) stimulated the45Ca2+ uptake in a concentration-dependent manner. Stimulation of45Ca2+ uptake in Na+-deficient islets was associated with an enhancement of the basal insulin release. Total abolishment of glucose-stimulated45Ca2+ uptake in K+-deficient islets did not preclude a significant secretory response to glucose. It is concluded that the lanthanum-nondisplaceable45Ca2+ uptake shows a partial correlation to insulin release.  相似文献   
12.
We often see perilobular necrosis of the pancreas in patients with liver disease at autopsy. This study was undertaken to determine the frequency and the mechanism of development of pancreatic perilobular necrosis in patients with liver disease. Pancreatic perilobular necrosis was seen in 21 per cent of 261 autopsied patients: in 41 per cent of 73 autopsied patients with liver disease and in 13 per cent of 188 autopsied patients without liver disease. Moreover, splanchnic congestion was present in 90 per cent of 30 pancreatic perilobular necrosis patients with liver disease. These data indicate that patients with liver disease develop perilobular necrosis of the pancreas more often than patients without liver disease, and that the high frequency may be a sequela of splanchnic congestion; that is, congestion of the pancreas and endotoxaemia due to congestion of the gut.  相似文献   
13.
Fine-needle aspiration biopsy of the pancreas: a study of 61 cases   总被引:1,自引:0,他引:1  
Eighty-six fine-needle aspirates (FNAs) of pancreas from 74 patients were reviewed. Histological confirmation or clinical follow-up of the final diagnosis was available in 61 aspirates from 49 patients. Of 42 proven malignant cases, FNAs were diagnosed as positive in 21 (50%), suspicious in 4 (9.5%), negative in 12 (28.6%), and unsatisfactory in 5 (11.9%). Of 19 proven benign cases, FNAs were diagnosed as negative in 15 (78.9%) and unsatisfactory in 4 (21%). This resulted in a 50% sensitivity, a 100% specificity, a diagnostic efficiency of 59%, a predictive value of a positive test of 100%, and a predictive value of a negative test of 55.6%. Thirty-six primary pancreatic adenocarcinomas and six metastatic tumors to the pancreas were encountered. Benign cases were attributed to anatomical pancreatic variants, acute pancreatitis, abscess, chronic pancreatitis, and pseudocysts. Pancreatic FNA was safe, accurate, and relatively inexpensive, but it was relatively insensitive in the diagnosis of malignancy.  相似文献   
14.
The effect of noradrenaline (NE) on rat islet -cells was examined. NE reduced insulin secretion from rat islets exposed to extracellular solutions containing glucose at 5.5 or 16.6 mM. In islets treated with pertussis toxin (PTX), however, NE increased insulin secretion. The NE-induced augmentation of insulin secretion was inhibited by prazosin. In intact islets, NE increased phospholipase C (PLC) activity, an effect that was prevented by treatment of islets with U-73122. NE elevated intracellular [Ca2+] ([Ca2+]i) in isolated -cells independently of PTX. Although this NE effect was inhibited by prazosin, phenylephrine did not mimic it. The [Ca2+]i response to NE was also prevented by the treatment of cells with U-73122. NE produced depolarization of -cells followed by nifedipine-sensitive action potentials. NE reduced the whole-cell membrane currents through ATP-sensitive K+ channels (KATP), responsible for the depolarization. This NE effect was prevented by treatment of -cells with U-73122 or BAPTA/AM. Although at least some of our results imply the presence of 1-adrenoceptors, -cells were not stained by a polyclonal IgG antibody recognizing all adrenergic 1-receptor subtypes so far identified. These results suggest that an interaction of NE with an unknown type of receptor activates rat islet -cells via a PLC-dependent signal pathway. This effect is, however, masked by the inhibitory action via a PTX-sensitive pathway also activated by NE.  相似文献   
15.
Radiation therapy for pancreatic cancer: eleven year experience at the JCRT   总被引:1,自引:0,他引:1  
Radiation therapy (XRT) for 41 patients with unresectable pancreatic cancer resulted in a median survival of 7.0 months. There was no difference in median survival for patients receiving external beam alone (3500 to 5600 cGy) (n = 28), intraoperative (IORT) boost plus external beam (5040 to 6750 cGy) (n = 9), or a gold-198 implant +/- external beam radiation (n = 4). A pilot study using orthovoltage IORT boost indicates no acute toxicity with doses of 1250 to 1750 cGy. Serious late damage has not been observed in any patients followed to 2 years. Local recurrence in patients treated post-operatively after "radical" surgery occurred in one of 10 (10%). This adjuvant treatment is safe and appears to improve local control rates compared to historical data, but survival is still poor. The median survival for the post-operative group is 10 months; three patients are alive without disease 8 months to 8.3 years after treatment.  相似文献   
16.
目的 研究胰岛的血液引流与胰腺外分泌的机能联系与临床意义。方法 运用微血管树脂 /墨汁灌注扫描电镜 /光镜观察法、保留动态及组织信息在静态样本的微循环观察法、FITC标记红细胞 (FITC- RBC)荧光活体显微镜观察法以及计算机图像处理微血管三维重建法 ,对 11例男性尸体、40只猴、2 4只狗、62只鼠、2 4只兔的胰岛血液引流通道与胰腺外分泌腺泡的关系进行了系统研究。结果 不同动物的内分泌胰岛血液主要经胰岛的三种类型输出血管引流至不同的外分泌腺泡区域 ,灵长类的部分胰岛血液还引流至邻近的小胰岛 ,研究者根据胰岛引流系统的特征对其进行了分类及命名 :1连续型引流系统 ,所有胰岛具有这类引流 (输出 )管道 ,其管径细 ,行程短、引流至胰岛周围的腺泡毛细血管区域。 2聚合型引流系统 ,为部分胰岛所有 ,其管径粗、行程长 ,引流至远离胰岛的腺泡毛细血管区域。 3跨越型引流系统 ,为部分胰岛所有 ,其输出管道越过小叶间隔引流至另一胰腺小叶的腺泡毛细血管区域 ,而这一小叶往往没有胰岛存在。 4胰岛 -胰岛型引流系统 ,灵长类部分胰岛的血液通过胰岛 -胰岛型引流通道回流至邻近的小胰岛。结论 胰岛具有完善联系外分泌腺泡的引流系统 ,提示含有高浓度胰岛内分泌激素的胰岛血液可能对外分泌腺泡的机能  相似文献   
17.
18.
Introduction and importanceThe incidence of patients with liver cirrhosis (LC) is increasing. Patients with LC are known to have a greater risk of postoperative morbidity and mortality than patients without LC. A treatment option such as pancreaticoduodenectomy (PD) has not been validated to be safe for these patients, especially those with pancytopenia due to portal hypertension (PH). Providing an effective treatment option for these patients is essential.Case presentationHerein, we describe a patient with pancreatic cancer with pancytopenia due to LC that was successfully treated with PD combined with splenectomy. The patient was a 70-year-old woman who was referred to our hospital for evaluation of a mass in the pancreatic head after she developed obstructive jaundice. She was diagnosed with T2N0M0, Stage IB pancreatic cancer and pancytopenia due to PH associated with LC. She received 2 cycles of adjuvant gemcitabine/S-1 chemotherapy and underwent radical subtotal stomach-preserving pancreaticoduodenectomy with splenectomy to improve her pancytopenia. Histopathological examination of the resected specimen revealed an R0 resection showing an Evans grade IIa histological response. Her pancytopenia improved rapidly after surgery.Clinical discussionStrict indications for PD, haemostatic control of intraoperative bleeding, and optimal perioperative management were important for preventing hepatic decompensation in this patient. Splenectomy is effective for thrombocytopenia due to LC; however, attention to postoperative complications such as overwhelming post-splenectomy infection and portal vein thrombosis is required.ConclusionFor patients with pancreatic cancer with pancytopenia due to LC, PD combined with splenectomy plus optimal perioperative management is effective.  相似文献   
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20.
颅-面联合径路前颅底区肿瘤切除术   总被引:1,自引:0,他引:1  
目的完整切除侵及前颅底区肿瘤,提高治愈率.方法采用颅-面联合径路,其中单用带血管蒂帽状腱膜-颅骨膜瓣4例,帽状腱膜-颅骨膜瓣加肋骨片或钛网板各2例修补颅底.8例未做颅底重建.结果肿瘤全切16例,无1例手术死亡、长期脑脊液漏或/和颅内感染,5例恶性肿瘤患者术后存活3~5年;3例存活1~2年;均未见肿瘤复发.另4例在2年内分别死于局部复发和远处转移,4例良性肿瘤患者术后随诊1~7年未见复发.结论颅-面联合径路前颅底区肿瘤切除术,具有术野大、显露清楚、安全可靠,有利于肿瘤整块切除.硬脑膜修补和颅底重建,可有效地防止脑脊液漏和颅内感染等并发症.  相似文献   
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