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\newcolumntype{M}[1]{>{\centering\arraybackslash}m{#1}}
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\graphicspath{ {Figures/} }
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\usepackage{enumitem}
\setitemize{noitemsep,topsep=0pt,parsep=0pt,partopsep=0pt} % less gaps in itemize sections
\setenumerate{noitemsep,topsep=0pt,parsep=0pt,partopsep=0pt}
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{\parindent \z@ \raggedright \normalfont
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% \@chapapp\space % removed
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\nobreakspace{}% \par\nobreak\vskip 20\p@ % replaced
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\titlespacing{\subsubsection}{0pt}{20pt}{3pt}
\usepackage{etoolbox}
\AtBeginEnvironment{tabular}{\small}
\AtBeginEnvironment{longtable}{\small}
\usepackage{tabularx}
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\setstretch{1.5}
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\usepackage{titlesec}
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\begin{landscape}
\renewcommand{\arraystretch}{1.0}{
\begin{longtable}{M{2.5cm}M{7.20cm}M{7.25cm}M{7.5cm}}
\caption{Type of debridement techniques. \textit{Adapted from Gray et al. (2011), Vowden (2011).}}
\label{techn}
\hline \hline \textbf{Type} & \textbf{Mode of Action} & \textbf{Advantages} & \textbf{Disadvantages} \\ \hline
\textbf{Surgical} & Removal of necrotic and healthy tissue to achieve a healthy bleeding wound & \tabitem Selective \par \tabitem Appropriate for large wound areas & \tabitem Need to occur in a surgical room \par \tabitem Anaesthetic needed as a painful procedure \par \tabitem Expensive \\ \hline
\textbf{Sharp} & Removal of necrotic tissue just above the limit of healthy tissue using surgical tools like scalpel, scissors and/or forceps & \tabitem Selective and quick \par \tabitem No anaesthetic needed \par \tabitem Can be undertaken in conjunction with other therapies \par \tabitem Can be done as a bedside procedure & \tabitem Does not achieve total debridement \par \tabitem It is based on the ability of the clinicians to recognise different tissues \\ \hline
\textbf{Enzymatic} & Use of exogenous proteolytic enzymes (e.g. collagenase, papain) to break down necrotic tissue & \tabitem Selective technique & \tabitem Slow process, but in conjunction with moisture-retentive dressings, it can increase debriding activity \\ \hline
\textbf{Mechanical} & Can be achieved with different tools and/or equipment. Most common: wet-to-dry gauze dressings. It consists in applying wet gauze to the wound that dries, adhering to the top layer of the wound, pulling it off upon removal & \tabitem Wet-to-dry is not selective \par \tabitem Newer techniques are more selective, faster and relatively pain-free (e.g. monofilament pad) & \tabitem Can be very painful for the patient \par \tabitem High numbers of dressings needed can result in a rather expensive technique \par \tabitem Gauze can leave remnants in the wound that could lead to further inflammation \\ \hline
\textbf{Autolytic} & Use of endogenous proteolytic enzymes to break down necrotic tissue. Requires moist wound environment (via moisture-controlling dressings) & \tabitem Can be used as a pre-debridement technique or for maintenance debridement & \tabitem Slow process, and it could lead to potential infection and maceration \\ \hline
\textbf{Biological} & Use of lab-grown larvae of green bottle fly. They release an enzyme that breaks down both necrotic tissue and bioburden & \tabitem Highly selective and rapid \par \tabitem Larvae release ammonia, increasing wound pH and acting as a preventative measure for further biofilm growth & \tabitem Not suitable for all patients or wounds \par \tabitem Costs are higher than autolytic, but treatment time is shorter \\ \hline
\textbf{Ultrasonic} & Devices deliver ultrasound directly onto the wound bed or via atomised solution & \tabitem Fast and selective \par \tabitem Devices present irrigation systems and different probes to be used on different wound types & \tabitem High cost \par \tabitem Long set up and clean up times \par \tabitem Not commonly available \\ \hline
\end{longtable}
}
\end{landscape}
我收到的错误是：
{\ifnum 0=`}\fi \penalty \@M \futurelet \@let@token \LT@@h...
l.198 \hline
\hline \textbf{Type} & \textbf{Mode of Action} & \textbf{Ad...
I expect to see \noalign only after the \cr of
an alignment. Proceed, and I'll ignore this case.
! Misplaced \omit.
\multispan ->\omit
\@multispan
l.198 \hline \hline
\textbf{Type} & \textbf{Mode of Action} & \textbf{Ad...
I expect to see \omit only after tab marks or the \cr of
an alignment. Proceed, and I'll ignore this case.
和
l.198 \hline \hline
\textbf{Type} & \textbf{Mode of Action} & \textbf{Ad...
You have given more \span or & marks than there were
in the preamble to the \halign or \valign now in progress.
So I'll assume that you meant to type \cr instead.
出现在突出显示的行中。
编译后的 PDF 看起来如下，对我来说没问题：
答案1
如果我猜一个例子：
\documentclass{article}
\usepackage{pdflscape}
\usepackage{longtable}
\usepackage{array}
\newcolumntype{M}[1]{m{#1}}
\begin{document}
\begin{landscape}
%\begingroup
\renewcommand{\arraystretch}{1.0}
\begin{longtable}[ht]{M{2.5cm}M{7.20cm}M{7.25cm}M{7.5cm}}
\caption{Type of debridement techniques. \textit{Adapted from Gray et al. (2011), Vowden (2011).}}
\label{techn}
\centering
\\ \hline
\textbf{Type} & \textbf{Mode of Action} & \textbf{Advantages} & \textbf{Disadvantages} \\ \hline
\textbf{Surgical} & Removal of necrotic and healthy tissue to achieve a healthy bleeding wound & \begin{itemize}
\item Selective
\item Appropriate for large wound areas
\end{itemize} & \begin{itemize}
\item Need to occur in a surgical room
\item Anaesthetic needed as a painful procedure
\item Expensive
\end{itemize} \\ \hline
\textbf{Sharp} & Removal of necrotic tissue just above the limit of healthy tissue using surgical tools like scalpel, scissors and/or forceps & \begin{itemize}
\item Selective and quick
\item No anaesthetic needed
\item Can be undertaken in conjunction with other therapies
\item Can be done as a bedside procedure
\end{itemize} & \begin{itemize}
\item Does not achieve total debridement
\item It is based on the ability of the clinicians to recognise different tissues
\end{itemize}\\ \hline
\textbf{Enzymatic} & Use of exogenous proteolytic enzymes (e.g. collagenase, papain) to break down necrotic tissue & \begin{itemize}
\item Selective technique
\end{itemize} & \begin{itemize}
\item Slow process, but in conjunction with moisture-retentive dressings, it can increase debriding activity
\end{itemize} \\ \hline
\textbf{Mechanical} & Can be achieved with different tools and/or equipment. Most common: wet-to-dry gauze dressings. It consists in applying wet gauze to the wound that dries, adhering to the top layer of the wound, pulling it off upon removal & \begin{itemize}
\item Wet-to-dry is not selective
\item Newer techniques are more selective, faster and relatively pain-free (e.g. monofilament pad)
\end{itemize} & \begin{itemize}
\item Can be very painful for the patient
\item High numbers of dressings needed can result in a rather expensive technique
\item Gauze can leave remnants in the wound that could lead to further inflammation
\end{itemize} \\ \hline
\textbf{Autolytic} & Use of endogenous proteolytic enzymes to break down necrotic tissue. Requires moist wound environment (via moisture-controlling dressings) & \begin{itemize}
\item Can be used as a pre-debridement technique or for maintenance debridement
\end{itemize} & \begin{itemize}
\item Slow process, and it could lead to potential infection and maceration
\end{itemize} \\ \hline
\textbf{Biological} & Use of lab-grown larvae of green bottle fly. They release an enzyme that breaks down both necrotic tissue and bioburden & \begin{itemize}
\item Highly selective and rapid
\item Larvae release ammonia, increasing wound pH and acting as a preventative measure for further biofilm growth
\end{itemize} & \begin{itemize}
\item Not suitable for all patients or wounds
\item Costs are higher than autolytic, but treatment time is shorter
\end{itemize} \\ \hline
\textbf{Ultrasonic} & Devices deliver ultrasound directly onto the wound bed or via atomised solution & \begin{itemize}
\item Fast and selective
\item Devices present irrigation systems and different probes to be used on different wound types
\end{itemize} & \begin{itemize}
\item High cost
\item Long set up and clean up times
\item Not commonly available
\end{itemize} \\ \hline
\end{longtable}
\end{landscape}
%\endgroup
\end{document}
它会产生错误
! LaTeX Error: Something's wrong--perhaps a missing \item.
See the LaTeX manual or LaTeX Companion for explanation.
Type H <return> for immediate help.
...
l.15 \\ \hline
?
\hline只有当你滚动浏览此错误时，你才会看到来自（\multispan）内部定义的虚假错误
! Misplaced \noalign.
\hline ->\noalign
{\ifnum 0=`}\fi \penalty \@M \futurelet \@let@token \LT@@h...
l.15 \\ \hline
?
! Misplaced \omit.
\multispan ->\omit
\@multispan
l.16 \textbf
{Type} & \textbf{Mode of Action} & \textbf{Advantages}...
?
原始错误是由于\centering该位置仅定义\\ 结束居中文本行而不是表格行，因此您可以删除，然后所有错误都会出现：
\documentclass{article}
\usepackage{pdflscape}
\usepackage{longtable}
\usepackage{array}
\newcolumntype{M}[1]{m{#1}}
\begin{document}
\begin{landscape}
%\begingroup
\renewcommand{\arraystretch}{1.0}
\begin{longtable}[ht]{M{2.5cm}M{7.20cm}M{7.25cm}M{7.5cm}}
\caption{Type of debridement techniques. \textit{Adapted from Gray et al. (2011), Vowden (2011).}}
\label{techn}
%%%%%%%%%%%%%% \centering
\\ \hline
\textbf{Type} & \textbf{Mode of Action} & \textbf{Advantages} & \textbf{Disadvantages} \\ \hline
\textbf{Surgical} & Removal of necrotic and healthy tissue to achieve a healthy bleeding wound & \begin{itemize}
\item Selective
\item Appropriate for large wound areas
\end{itemize} & \begin{itemize}
\item Need to occur in a surgical room
\item Anaesthetic needed as a painful procedure
\item Expensive
\end{itemize} \\ \hline
\textbf{Sharp} & Removal of necrotic tissue just above the limit of healthy tissue using surgical tools like scalpel, scissors and/or forceps & \begin{itemize}
\item Selective and quick
\item No anaesthetic needed
\item Can be undertaken in conjunction with other therapies
\item Can be done as a bedside procedure
\end{itemize} & \begin{itemize}
\item Does not achieve total debridement
\item It is based on the ability of the clinicians to recognise different tissues
\end{itemize}\\ \hline
\textbf{Enzymatic} & Use of exogenous proteolytic enzymes (e.g. collagenase, papain) to break down necrotic tissue & \begin{itemize}
\item Selective technique
\end{itemize} & \begin{itemize}
\item Slow process, but in conjunction with moisture-retentive dressings, it can increase debriding activity
\end{itemize} \\ \hline
\textbf{Mechanical} & Can be achieved with different tools and/or equipment. Most common: wet-to-dry gauze dressings. It consists in applying wet gauze to the wound that dries, adhering to the top layer of the wound, pulling it off upon removal & \begin{itemize}
\item Wet-to-dry is not selective
\item Newer techniques are more selective, faster and relatively pain-free (e.g. monofilament pad)
\end{itemize} & \begin{itemize}
\item Can be very painful for the patient
\item High numbers of dressings needed can result in a rather expensive technique
\item Gauze can leave remnants in the wound that could lead to further inflammation
\end{itemize} \\ \hline
\textbf{Autolytic} & Use of endogenous proteolytic enzymes to break down necrotic tissue. Requires moist wound environment (via moisture-controlling dressings) & \begin{itemize}
\item Can be used as a pre-debridement technique or for maintenance debridement
\end{itemize} & \begin{itemize}
\item Slow process, and it could lead to potential infection and maceration
\end{itemize} \\ \hline
\textbf{Biological} & Use of lab-grown larvae of green bottle fly. They release an enzyme that breaks down both necrotic tissue and bioburden & \begin{itemize}
\item Highly selective and rapid
\item Larvae release ammonia, increasing wound pH and acting as a preventative measure for further biofilm growth
\end{itemize} & \begin{itemize}
\item Not suitable for all patients or wounds
\item Costs are higher than autolytic, but treatment time is shorter
\end{itemize} \\ \hline
\textbf{Ultrasonic} & Devices deliver ultrasound directly onto the wound bed or via atomised solution & \begin{itemize}
\item Fast and selective
\item Devices present irrigation systems and different probes to be used on different wound types
\end{itemize} & \begin{itemize}
\item High cost
\item Long set up and clean up times
\item Not commonly available
\end{itemize} \\ \hline
\end{longtable}
\end{landscape}
%\endgroup
\end{document}