全文获取类型
收费全文 | 4470篇 |
免费 | 271篇 |
国内免费 | 238篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 51篇 |
妇产科学 | 8篇 |
基础医学 | 182篇 |
口腔科学 | 22篇 |
临床医学 | 652篇 |
内科学 | 637篇 |
皮肤病学 | 19篇 |
神经病学 | 5篇 |
特种医学 | 226篇 |
外科学 | 1588篇 |
综合类 | 759篇 |
预防医学 | 151篇 |
药学 | 315篇 |
3篇 | |
中国医学 | 133篇 |
肿瘤学 | 212篇 |
出版年
2024年 | 7篇 |
2023年 | 62篇 |
2022年 | 162篇 |
2021年 | 153篇 |
2020年 | 133篇 |
2019年 | 109篇 |
2018年 | 123篇 |
2017年 | 116篇 |
2016年 | 145篇 |
2015年 | 167篇 |
2014年 | 350篇 |
2013年 | 336篇 |
2012年 | 325篇 |
2011年 | 271篇 |
2010年 | 252篇 |
2009年 | 229篇 |
2008年 | 219篇 |
2007年 | 224篇 |
2006年 | 202篇 |
2005年 | 177篇 |
2004年 | 148篇 |
2003年 | 108篇 |
2002年 | 115篇 |
2001年 | 116篇 |
2000年 | 91篇 |
1999年 | 77篇 |
1998年 | 57篇 |
1997年 | 67篇 |
1996年 | 46篇 |
1995年 | 57篇 |
1994年 | 54篇 |
1993年 | 26篇 |
1992年 | 36篇 |
1991年 | 30篇 |
1990年 | 24篇 |
1989年 | 22篇 |
1988年 | 23篇 |
1987年 | 16篇 |
1986年 | 13篇 |
1985年 | 8篇 |
1984年 | 12篇 |
1983年 | 6篇 |
1982年 | 14篇 |
1981年 | 15篇 |
1980年 | 9篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1976年 | 9篇 |
1972年 | 2篇 |
1970年 | 1篇 |
排序方式: 共有4979条查询结果,搜索用时 15 毫秒
1.
目的:探讨腹腔镜胆囊切除术(LC)中意外胆囊癌(unexpected gallb ladder carc inom a,UGC)的处理措施。方法:回顾分析本院955例LC术中遇到的12例(1.26%)UGC的临床资料。结果:随诊3~36个月,平均18个月。迄今全部存活。5例PT1、5例PT2、1例PT3(中转开腹)随访至今未发现癌复发及转移。1例PT2因拒绝根治术,现出现肝多发转移。1例PT4因腹腔种植转移,无法根治,故仅部分切除胆囊(胆囊粘连重),以解决急性胆囊炎问题,现有腹水、恶液质表现。所有病例均未见脐部戳孔处肿瘤种植转移。结论:LC术中应常规切开胆囊标本,必要时送术中冰冻。PT1单纯切除胆囊已足够;PT2要额外楔形切除肝组织及区域淋巴结;PT3中转开腹,行根治手术或姑息手术。 相似文献
2.
MR T2加权成像显示胆囊壁增厚点状高信号的意义 总被引:1,自引:1,他引:0
目的研究病理组织学证实的胆囊腺肌瘤病、慢性胆囊炎和管壁增厚型胆囊腺癌在MRL加权成像(T2WI)显示病变胆囊壁点状高信号的特征。方法38例患者(胆囊腺肌瘤病16例,慢性胆囊炎13例,管壁增厚型胆囊腺癌9例),每例均进行了MR常规T1WI、常规T2WI和3mm薄层T2WI及MR胰胆管成像(MRCP)。所有患者均接受了胆囊切除手术。2名高年资放射科医生共同分析不同序列MRI,观察胆囊壁增厚及T2WI显示病变胆囊壁点状高信号的不同表现,将观察结果与病理组织学检查所见对照。结果所有患者的胆囊壁均明显增厚,厚度范围5~15mm,平均9mm。T2WI显示病变胆囊壁存在各种各样的点状高信号,在胆囊腺肌瘤病,点状高信号分布于整个增厚的胆囊壁,且数量较多(5~15个/cm^2),较大(直径2~7mm),边界清楚,呈现中等至明显高信号;在慢性胆囊炎,点状高信号主要位于增厚胆囊壁的黏膜侧,数量较少(3~5个/cm^2),较小(直径2~4mm),边界清楚,呈中等至明显高信号;在管壁增厚型胆囊腺癌,点状高信号边界欠清,呈现稍高信号,其数量和大小差异较大,分布范围取决于癌组织浸润胆囊壁的深度。结论胆囊腺肌瘤病、慢性胆囊炎和管壁增厚型胆囊腺癌在T2WI呈现的点状高信号有一定差别,正确识别这些点状高信号的特征有助于鉴别诊断良恶性胆囊壁增厚。 相似文献
3.
K. Singh 《International urogynecology journal》2002,13(1):50-51
The author reports a complicated recurrence of genital tract fistula. The initial vesicovaginal fistula resulted from obstructed
labor, which was subsequently surgically managed without success. The patient had a recurrent vesicovaginal fistula that was
formed by the erosion of vesical stones through the anterior endopelvic fascia into the vagina. The stones eventually eroded
into the rectum, resulting in the formation of a complex vesicovaginal and rectovaginal fistula. 相似文献
4.
Sonographic evaluation of gallbladder kinetics: in vitro and in vivo comparison of different methods to assess gallbladder emptying. 总被引:3,自引:0,他引:3
Bernd Wedmann Gabriele Schmidt Martin Wegener Christoph Coenen Dieter Ricken Cornelia Drge 《Journal of clinical ultrasound : JCU》1991,19(6):341-349
In an in vitro study, 10 gallbladders of adult pigs and 6 gallbladders of lambs, all removed immediately after slaughtering, were stimulated in a water bath by electric means to induce active contraction. Gallbladder emptying was followed by ultrasonography employing five measurement procedures: (1) gallbladder width, (2) longitudinal planimetry, (3) transverse planimetry, (4) ellipsoid method, and (5) sum of cylinders method. In an in vivo investigation, gallbladder emptying of 30 volunteers (12 healthy subjects, 18 diabetics) was evaluated in the same way after ingestion of a fatty meal. Gallbladder width was found to be unsuitable to estimate the decrease in gallbladder volume due to a nonlinear relation of the parameters. Longitudinal planimetry tended to be less valid than transverse planimetry in assessing gallbladder volume reduction. The most valid estimation of gallbladder volume decreases was obtained by the two three-dimensional procedures. However, in neither in vitro nor in vivo could a significant difference between the sum of cylinders method and the ellipsoid method in determining relative volume reduction be established. We conclude that a three-dimensional measurement procedure should be used for valid assessments of gallbladder motility. However, according to our data there is no advantage in using the time-consuming sum of cylinders method compared to the simple ellipsoid method. 相似文献
5.
雌激素及其受体与胆囊癌关系的研究现状及进展 总被引:2,自引:0,他引:2
目的:探讨并讨论雌激素及其抗体与胆囊癌的关系.方法:阅读关于雌激素和胆囊癌方面的文献并进行总结.结果:雌激素在胆囊癌转变过程中起极为重要的作用.结论:研究胆囊癌患者血清中的雌激素水平对胆囊癌的发生、发展、预后及指导相应临床内分泌治疗具有重要的理论意义. 相似文献
6.
Summary It has been suggested that urinary sialidase may play a role in the formation of renal stones. The present study was therefore undertaken to compare spectrophotometrically the different types of sialic acid concentrations and sialidase activities in fresh first morning urine specimens of men (21–65 years) with (13) and without (9) calcium oxalate renal stones. Although the free urinary sialic acid concentrations of the two groups of men were statistically about the same (P=0.0614), the total (P=0.003) and bound (P=0.0012) urinary sialic acid concentrations differed significantly. Both the total and bound sialic acid concentrations were lower in the urine specimens of the stone patients than in their healthy counterparts. This decrease in urinary sialic acid concentrations was firstly thought to be the result of elevated breakdown enzymes of sialic acid, which would favour the production of pyruvate. However, spectrophotometric determinations of the endogenous pyruvate concentrations of the two types of urine specimens did not differ significantly (P=0.0708). Secondly, the decrease in total urinary total sialic acid concentration of stone patients, could be attributed to less sialic acid synthesis or less renal excretion. Therefore, the same experiments were repeated using serum of 13 patients and 9 healthy men. Conversely, the total (P=0.4425) and bound (P=0.2850) serum sialic acid concentrations were found to be similar in the two types of subjects. However, the free serum sialic acid concentration of stone patients was significantly lower than in the healthy subjects (P=0.0062). This phenomenon is also reflected in the average ratio for serum free: bound sialic acid in healthy and stone patients, 1:7.9 and 1:18.7 respectively (P=0.0009). The lower free serum sialic acid concentration may lead to lower renal excretions of sialic acid. This may explain the decrease in total urinary sialic acid concentration in stone patients. The lower bound urinary sialic acid concentrations in patients was also reflected in the urinary free: bound sialic acid ratio for healthy (1:2.3) and stone patients (1:1.3). The difference between these two groups of men was highly significant (P=0.0001). This phenomenon might be explained by the urinary sialidase activities, which was spectrophotometrically determined at 334 nm at 37°C of 11 patients with stones and 17 healthy men. The ages of both groups of men were the same (P=0.326). An increase in urinary sialidase activity was observed with the stone patients (P=0.00001) when compared to specimens of healthy men. This might explain the decrease in urinary bound sialic acid concentration of the stone group. It seems from these results that the urinary concentration of sialic acid and the activity of urinary sialidase, may play a role in the pathogenesis of the multifactorial disease, urolithiasis. 相似文献
7.
Hidekazu Mukai Hiroshi Yoshinaga Akihiko Watanabe Hitoshi Fujiwara Tsuyoshi Fujita 《Digestive endoscopy》2004,16(Z1):S58-S61
After removal of intraductal stones, a 10‐Fr or 7‐Fr pancreatic stent was placed in 16 patients with upstream ductal dilation proximal to a stricture of the main pancreatic duct. Stents were removed after a mean duration of 52.5 days. Nine patients underwent repeated stenting. About one year after removal of the initial stent, when the remaining upstream ductal dilation was found on follow‐up pancreatograms, the next stent was replaced. Repeated stenting improved outflow of pancreatic juice more effectively than one‐time stenting. Correlation between long‐term pain relief without recurrence of intraductal stones and reduction of duct diameter was also shown. Stent occlusion was observed in 14 of 30 stents. Stent occlusion was frequently associated with recurrence of pancreatitis and intraductal stones, and was also associated with morphologic changes in the pancreatic ductal system. Although there were no significant differences between stent patency of the initial stents and that of the next stents, stent patency of 10‐Fr stents was superior to that of 7‐Fr stents. 10‐Fr stents should be removed within 8 weeks and 7‐Fr stents should be removed within 4 weeks for the prevention of stent occlusion. Repeated stenting with short‐term stenting is therefore considered a safe and effective protocol of endoscopic pancreatic stenting. 相似文献
8.
E. Croce M. Golia M. Azzola R. Russo L. Crozzoli S. Olmi C. Pompa M. Borzio 《Surgical endoscopy》1996,10(11):1064-1068
Background: Thirty-three patients were candidates for laparoscopic choledochotomy. The indications for this operation are described.
Methods: The procedure was completed 32 times (97%). We had 29 successful common bile duct (CBD) clearances, three negative explorations,
and one failed clearance which needed to be converted to laparotomy. All the completed procedures ended with primary closure
of the main duct. Median duration of surgery was 180 min (range 100–300), including three associated laparoscopic procedures.
Results: There were three postoperative complications (9.4%), none major. Average postoperative hospital stay was 7.1 days (range
4–14). In May–June 1995 we controlled 31 out of the 32 consecutive patients (one patient was lost to follow-up) who had a
successful laparoscopic choledochotomy from October 1991 to December 1994. Median follow-up was 22 months (range 5–44). Besides
clinical control, 23 patients also had ultrasound (US) controls and 24 had blood tests. Eleven had intravenous cholangiotomography.
Two patients died 11 and 22 months after the operation for unrelated causes and without biliary symptoms. Two patients had
umbilical hernias. One had a small residual asymptomatic stone, which was removed endoscopically. None had signs of postoperative
CBD stricture. At US, CBD was ≤7 mm in 15 patients, 8–10 mm in four patients, and 10–12 mm in three patients. The last group
had preoperative CBD dilation, too. We could compare preoperative and postoperative CBD diameters in 22 patients: 11 had no
change; in nine it decreased; and two had a slight increase (8–10 mm).
Conclusions: We conclude that laparoscopic choledochotomy with primary closure is a very good operation: It has a high success rate and
low morbidity. Mortality is nil so far. Medium-term results are very positive: We had no CBD stricture and only one case of
asymptomatic residual stone, which could have been avoided. Our results suggest that intraductal biliary drainage is useless,
and its specific complications are well known.
Received: 20 October 1995/Accepted: 28 February 1996 相似文献
9.
A stratified intraoperative surgical strategy is mandatory during laparoscopic common bile duct exploration for common bile duct stones 总被引:3,自引:0,他引:3
J. F. Gigot B. Navez J. Etienne E. Cambier P. Jadoul P. Guiot P. J. Kestens 《Surgical endoscopy》1997,11(7):722-728
Background: Open exploration and endoscopic sphincterotomy (ES) remain the preferred treatment of common bile duct stones (CBDS). The
recent spread of laparoscopy has worsened the dilemna of choosing between surgical and endoscopic treatment of CBDS. The aim
of this study was to critically evaluate the results of our preliminary experience with laparoscopic common bile duct exploration
(CBDE) for CBDS.
Methods: Ninety-two consecutive patients were prospectively submitted to laparoscopic CBDE. Surgical strategy included an initial
transcystic approach or laparoscopic choledochotomy. Failure of stone clearance was managed by conversion to open CBDE or
by postoperative ES. Electrohydraulic lithotripsy and papillary balloon dilatation were selectively used. Stone clearance
was assessed by choledochoscopy and control cholangiography.
Results: The overall laparoscopic stone clearance in this series was 84% (transcystic route 63% and choledochotomy 93%). Conversion
to laparotomy was mandatory in 12% of the patients because of incomplete stone clearance and in 5% because of intraoperative
complications. Postoperative ES was required in 4% of the patients, giving an overall surgical success rate of 96%. When indicated
(small and limited number of stones located below the cysticocholedochal junction, with a dilated and patent cystic duct)
the transcystic route had the lower success rate, the higher complication rate, and the shorter operative time and postoperative
hospital stay. When indicated (accessible and dilated common bile duct over 7 mm), laparoscopic choledochotomy had the higher
success rate, the lower complication rate, the longer operative time, and the longer postoperative hospital stay, which is
related to associated external biliary drainage. The hospital mortality included two high-risk patients (2%) and the complications
rate was 15%.
Conclusions: Laparoscopic CBDE is safe in selected patients. A stratified intraoperative surgical strategy is mandatory in deciding between
a transcystic route and choledochotomy with specific indications for each approach. When feasible, laparoscopic choledochotomy
is more efficient and safe than the transcystic route, but it is associated with a longer postoperative hospital stay, which
is due to external biliary drainage.
Received: 7 May 1996/Accepted: 19 November 1996 相似文献
10.
Laparoscopic trans-cystic-duct common-bile-duct exploration 总被引:1,自引:0,他引:1
One thousand seventy-one consecutive laparoscopic cholecystectomies were performed. Routine cholangiography was employed with a 99% success rate. One hundred thirty patients were found to have common duct stones (CBDS). In 48 (37%) patients they were unsuspected. One hundred eleven patients underwent attempted trans-cystic-duct extraction techniques (TCD-CBDE). One hundred three (93%) were successful. The following techniques were employed: 101—biliary endoscopy, 23—ampullary balloon dilation, 2—fluoroscopic basket retrieval.The average operative time was 136 min. The average postsurgical stay was 3.7 days. There were 19 (17%) complications—6 (5%) major. There were 4 retained stones (2 intentional) and 1 death. Patients over 65 years of age had more complications and patients with unsuspected CBDS under 65 years of age had the fewest.TCD-CBDE is a safe, effective way to extract common duct calculi. Endoscopy and basket stone retrieval was the primary technique employed.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Nashville, Tennessee, USA, 18–19 April 1994 相似文献